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Objectives: To determine the level of calcium and vitamin D oral supplementation in patients in periodontal disease maintenance programmes., Design: Convenience survey., Setting: St. Louis Metropolitan region., Subjects and Methods: Patients (n = 228) in two university-based, periodontal disease maintenance programmes., Main Outcome Measures: Reported amounts of oral calcium and vitamin D supplementation were tested for differences based on gender and race., Results: The last published recommended daily intakes from the United States (US) Food and Nutrition Board (FNB) for adults >50 years of age are 1,200 mg calcium and 400 IU vitamin D (or 600 IU if over 70). The mean age of the 228 patients (125 females and 103 males) was 63.6 +/- 11.0 years (standard deviation). Of the 228 patients surveyed: (1) 204 (89%) were >50 years of age and of these, only 15 (7%) met the US FNB's recommended intakes of calcium and vitamin D from supplementation; (2) 138 (66%) reported that they took no oral supplementation, with significantly more males (n = 82) than females (n = 56) not taking supplementation (p = 0.03); (3) 88 (39%) took calcium supplementation, with females (947 +/- 511 mg/day) taking significantly (p <0.001) more than males (632 +/- 907 mg/day); and (4) 66 (29%) took vitamin D supplementation, with females(420 +/- 227 IU/day) taking approximately the same amount as males (443 +/- 317 IU/day, p >0.05). The amounts of oral supplementation did not vary with race (p >0.05)., Conclusion: The use of calcium and vitamin D supplementation has been promoted for years, yet the numbers of adults taking supplements remains low and the level of supplementation varies greatly. Knowledge of the benefits of supplementation needs to be better disseminated and research needs to be conducted to determine optimal levels of calcium and vitamin D supplementation.

Objective: To determine the significance of small arterially-enhancing liver lesions seen with magnetic resonance imaging (MRI) in patients with chronic liver disease., Material and Method: Our institutional review board approved this retrospective study, without requiring informed consent. Over a two-year period, 258 consecutive patients with cirrhosis or chronic hepatitis underwent multiphase three-dimensional, gadolinium-enhanced, breath-hold gradient-echo MRI. From this group, 29 patients underwent at least one follow-up MR study. When a small (< or = 20 mm) arterially-enhancing lesion was detected, the maximum diameter shape, signal intensities (T1-weighted and T2-weighted), and pattern of enhancement were evaluated to assess the associations between the imaging appearance on initial MR exam and subsequent behavior on follow-up imaging. Statistical testing was performed with JMP Statistical Software (SAS, Inc., Cary, NC) and StatXact 7 Statistical Software for Exact Nonparmetric Inference (Cytel, Inc., Cambride, MA)., Results: Sixty-five small (< or = 20 mm) arterially-enhancing lesions were detected in 29 patients. Ten of 65 lesions (15%) in nine patients were subsequently proven to represent hepatocellular carcinoma (HCC), while the remaining lesions either disappeared (46) or remained stable in size (9). Of the 10 lesions subsequently proven to represent HCC, eight lesions converted from hypo- or isointense to hyperintense on subsequent T2-weighted MRI (p < 0.001), seven lesions converted from hyper- or isointense to hypointense on subsequent T1-weighted images (p < 0.001), seven lesions demonstrated growth on subsequent MRI exam (mean increase in mean diameter = 1.4 cm), and five lesions subsequently developed rim enhancement that was not initially present., Conclusion: Small, arterially-enhancing lesions detected with MRI have a low likelihood of representing HCC, and MRI follow-up of such lesions is a reasonable approach. Lesions that increase in size, convert to hypointense on subsequent T1W images, convert to hyperintense in T2W images, or develop rim enhancement on follow-up MRI images are concerning and should prompt consideration of intervention.

The objective of this research was to develop and validate a custom computed tomography dose-reduction simulation technique for producing images that have an appearance consistent with the same scan performed at a lower mAs (with fixed kVp, rotation time, and collimation). Synthetic noise is added to projection (sinogram) data, incorporating a stochastic noise model that includes energy-integrating detectors, tube-current modulation, bowtie beam filtering, and electronic system noise. Experimental methods were developed to determine the parameters required for each component of the noise model. As a validation, the outputs of the simulations were compared to measurements with cadavers in the image domain and with phantoms in both the sinogram and image domain, using an unbiased root-mean-square relative error metric to quantify agreement in noise processes. Four-alternative forced-choice (4AFC) observer studies were conducted to confirm the realistic appearance of simulated noise, and the effects of various system model components on visual noise were studied. The "just noticeable difference (JND)" in noise levels was analyzed to determine the sensitivity of observers to changes in noise level. Individual detector measurements were shown to be normally distributed (p > 0.54), justifying the use of a Gaussian random noise generator for simulations. Phantom tests showed the ability to match original and simulated noise variance in the sinogram domain to within 5.6% +/- 1.6% (standard deviation), which was then propagated into the image domain with errors less than 4.1% +/- 1.6%. Cadaver measurements indicated that image noise was matched to within 2.6% +/- 2.0%. More importantly, the 4AFC observer studies indicated that the simulated images were realistic, i.e., no detectable difference between simulated and original images (p = 0.86) was observed. JND studies indicated that observers' sensitivity to change in noise levels corresponded to a 25% difference in dose, which is far larger than the noise accuracy achieved by simulation. In summary, the dose-reduction simulation tool demonstrated excellent accuracy in providing realistic images. The methodology promises to be a useful tool for researchers and radiologists to explore dose reduction protocols in an effort to produce diagnostic images with radiation dose "as low as reasonably achievable".

Objective: The purpose of our study was to retrospectively evaluate the effect of body weight and iodine dose on aortic and hepatic contrast enhancement in pediatric patients who underwent 64-MDCT of the abdomen and pelvis., Materials and Methods: Eighty-seven consecutive pediatric patients (50 boys and 37 girls; median age, 12.1 years; age range, 3.8-17.6 years) underwent standard abdominopelvic CT with a 64-MDCT scanner. Contrast medium (350 mg I/mL) was injected using a power injector at 2 mL/s followed by 15-20 mL of saline flush. According to our CT protocol, the volume of administered contrast medium was approximately 1.8 mL/kg of body weight, up to the maximum volume of 80 mL. CT scanning was initiated 60 seconds after the start of the contrast medium injection. CT attenuations of the aorta and liver were measured. For each patient, the injected contrast medium iodine mass per body weight index (g I/kg) (hereafter, iodine mass body index) was calculated. Linear regression analysis was performed between iodine mass body index and aortic and hepatic attenuations., Results: A wide range of patient weights (19-82 kg; mean, 48.6 kg [95% CI, 45.3-51.9 kg]) and contrast volumes (30-80 mL; median, 80.0 mL) were observed. The median attenuations were 149.0 HU (141.0-160.0 HU) for the aorta and 113.5 HU (109.5-120.0 HU) for the liver. Moderately high correlations were observed between iodine mass body index and aortic (Spearman's rho [r(s)] = 0.60 [0.45-0.72]; p < 0.001) and hepatic (r(s) = 0.60 [0.42-0.70]; p < 0.001) attenuations. The regression formulae for aortic attenuation (58.4 + 176.3 x iodine mass body index [p < 0.001]) and hepatic attenuation (58.7 + 108.5 x iodine mass body index [p < 0.001]) indicate that 1.5 and 1.8 mL/kg (350 mg I/mL) of contrast media are required to achieve 116 and 127 HU, respectively, of contrast-enhanced attenuation in the liver., Conclusion: In our study, using abdominal 64-MDCT in pediatric patients, we found that approximately 1.5 mL/kg, or 0.525 g I/kg, yields 116 HU of hepatic attenuation or 50-55 HU of hepatic enhancement.

Purpose: To retrospectively evaluate the effect of a log-rolling procedure and postvoiding residual (PVR) bladder urine volume on opacification of urinary bladder and ureters at multi-detector row computed tomographic (CT) urography., Materials and Methods: Institutional review board approval was obtained, and informed consent was waived for this retrospective HIPAA-compliant study. Triple-phase 16- or 64-detector row CT urographic images in 166 patients (88 men, 78 women; mean age, 58.9 years; range, 22-89 years) were evaluated retrospectively. Immediately prior to excretory phase scanning, 67 patients did and 99 did not undergo a log-rolling procedure on the CT table. PVR bladder urine volume was quantified as the largest cross-sectional area of the bladder measured on unenhanced images (PVR values). The degree of bladder opacification was quantified as the percentage of the total cross-sectional area of the bladder that was opacified on excretory phase images. Ureteral opacification was quantified as the percentage of ureteral length that contained enhanced urine. On the basis of PVR values, patients were stratified into four subgroups (2000 to 3000 to 4000 mm(2)). The Wilcoxon rank sum and Student t tests were used to evaluate differences., Results: Median degree of bladder opacification of the log-rolling versus non-log-rolling group was 100% versus 78% for PVR values of 2000 mm(2) or less (P < .01), 99% versus 79% for PVR values of more than 2000 to 3000 mm(2) or less (P = .01), 89% versus 79% for PVR values of more than 3000 to 4000 mm(2) or less (P < .05), and 64% versus 69% for PVR values of more than 4000 mm(2) (P = .96). There was no significant difference between ureteral opacification and log rolling or between bladder and ureteral opacification (P > .05)., Conclusion: Use of a log-rolling procedure prior to excretory phase CT urography increases the percentage of bladder opacification in patients with PVR values of 4000 mm(2) or less. No difference in ureteral opacification was observed between the log-rolling and non-log-rolling groups., ((c) RSNA, 2008.)

Rationale and Objectives: To retrospectively determine the value of magnetic resonance imaging (MRI)-directed breast ultrasonography (US) in the evaluation of indeterminate or suspicious lesions identified on contrast-enhanced, breast MRI., Materials and Methods: A total of 395 patients presenting for breast MRI during a 4-year period was retrospectively reviewed. Seventy-one patients were recommended for MRI-directed US for further characterization of indeterminate or suspicious breast lesions detected on MRI. Fifty-five patients (all female; age 31-80 years) had US. Their MRI and US were reviewed and tested for correlations with histologic results or long term follow-up. Logistic regression analyses were used to test for associations between MRI lesion characteristics and US detection rate., Results: US identified 46 of 97 (47%) lesions depicted at MRI from 55 patients (47 [85%] of these patients had histories of breast malignancies). Twelve cancers were found from the 97 lesions (12%). Biopsy was avoidable in 10 lesions (10%). The detection rate with US was slightly higher with "mass" (55% [23/42]) lesions described in MRI than "non-mass" lesions or lymph nodes (42% [23/55]). There was a significant positive association (odd ratio = 1.23: 95% CI = 1.05-1.43, P = .01) between US detection rate and MRI mass lesion size. There was no statistical significance between US detection rate and the presence of malignancies; 42% (5/12) of MRI malignant lesions were not visualized with US., Conclusions: MRI-directed US reduced the number of biopsies required for indeterminate or suspicious MRI lesions. Nevertheless, the lesions which were biopsied had a low rate of malignancy.

Objective: The purpose of our study was to evaluate the effect of body weight, height, body surface area (BSA), body mass index (BMI), and obesity on aortic contrast enhancement in cardiac MDCT., Materials and Methods: Seventy-three consecutive patients underwent cardiac CT angiography on a 64-MDCT scanner. Seventy-five mL of contrast medium (350 mg I/mL) was injected at 4.5 mL/s, followed by a 40-mL saline flush at 4.5 mL/s. The scanning delay of CT was determined with a bolus tracking technique. Aortic attenuation was measured over the aortic-root lumen. BMI and BSA were calculated from the patient's body weight and height. The patients were divided into low-(BMI < 30) and high-(> or = 30) BMI groups. Associations of aortic attenuation with body weight, height, BMI, and BSA were evaluated with regression analysis and the Student's t test., Results: Strong inverse correlations were seen between aortic attenuation and body weight (r = -0.73), height (r = -0.47), BMI (r = -0.63), and BSA (r = -0.74) (p < 0.001 for all). The regression formula of aortic attenuation versus body weight suggests that 1.0 mL/kg of contrast medium would yield a mean aortic attenuation of 355 H. The mean aortic attenuation was significantly higher in the low-BMI (352.6 +/- 59.1 H) than in the high-BMI (286.2 +/- 55.5 H) group. The regression formula for aortic attenuation on body weight was aortic attenuation = 586-3.1 body weight (p < 0.001) for the low-BMI group and aortic attenuation = 485-1.9 body weight (p < 0.001) for the high-BMI group, suggesting that the amount of contrast medium required with increased body weight is less in the high-BMI group. This group difference was less pronounced for the regression of aortic attenuation on BSA., Conclusion: To achieve a consistent contrast enhancement in cardiac CT angiography (CTA), contrast-medium dose should be adjusted with the body weight or the BSA (which accounts for both the body weight and height factors) to provide adjustment of iodine dose over a wide range of body sizes.

Rationale and Objectives: Stereology is a simple, fast method for object segmentation that involves counting the number of intersections of a randomly positioned grid over an object. The objectives of this study were to determine observer reliability in making stereologic- and ellipsoid-based measurements of uterine and leiomyoma volumes and to test the agreement between these two methods of measurement., Materials and Methods: Two observers made uterine and dominant leiomyoma volume measurements on MR images in 30 patients using stereology and the popular ellipsoid-based technique. Stereologic volume measurements were made from high-resolution T2 images in two perpendicular planes (axial and sagittal). Ellipsoid volume was calculated by multiplying the maximal sagittal, anteroposterior, and transverse dimensions by pi/6. For these measurements, interobserver reliability was tested with paired t-tests and percent differences were determined. A mean stereologic volume and a mean ellipsoid volume were determined and tested for agreement with a paired t-test. Percent differences were also calculated., Results: Stereologic measurements demonstrated excellent interobserver reliability with 0.3% difference in mean uterine volumes (P = .69) and 0.3% difference (P = .81) in mean leiomyoma volumes. The ellipsoid method resulted in poorer interobserver reliability with 7% difference (P = .01) in mean uterine volumes and 4% difference (p = .24) in mean leiomyoma volumes. The ellipsoid method also significantly overestimated uterine volumes by 14% (P < .01) compared with stereology., Conclusion: Stereology provided high interobserver reliability for leiomyoma and overall uterine volume measurements and was more reliable than the ellipsoid method, which uses linear measurements. Stereology appears well suited when precise volume measurements are desired for assessing response to uterine arterial embolization treatments.

Purpose: To prospectively correlate single- and multisection magnetic resonance (MR) imaging measurements with clinical measurements for assessment of abdominal adipose tissue volumes in healthy (control subjects), overweight, and diabetic overweight preadolescents and adolescents., Materials and Methods: The study was approved by the institutional internal review board and was HIPAA compliant. Informed consent was obtained from parents, and assent was obtained from control subjects and patients. Thirty total study subjects (20 male, 10 female; age range, 10-18 years; mean, 14.5 years) underwent MR imaging, anthropometric measurement, and dual x-ray absorptiometry (DXA). A computer-assisted software program was used to quantify subcutaneous, visceral, and total abdominal adipose tissue volumes. Single-section measurements at disk space L4-L5 and whole-abdominal multisection measurements were compared, and each method was tested for correlations with anthropometric and DXA measurements with Spearman rho and Pearson correlation (r) coefficients. Single- and multisection image analyses required 5 and 25 minutes per subject, respectively., Results: There was a high degree of correlation between single- and multisection MR imaging methods for measurement of subcutaneous (r = 0.97), visceral (r = 0.96), and total abdominal fat (r = 0.97). MR imaging fat measurements strongly correlated with anthropometric measurements (rho correlation range, 0.81-0.96; P

Purpose: To retrospectively evaluate the amount of contrast medium required with 16- and 64-section computed tomography (CT) for a given patient weight to achieve desirable contrast enhancement during pulmonary CT angiography., Materials and Methods: Institutional review board approval was obtained, and informed consent was not required for this HIPAA-compliant study. Eighty-five patients (35 men, 50 women; range, 22-87 years) who had undergone 16-section (n = 48) or 64-section (n = 37) CT for the detection of pulmonary embolism were retrospectively evaluated. Contrast medium containing 350 mg of iodine per milliliter was injected at a rate of 4 mL/sec. The injected volume corresponded to the injection rate multiplied by the sum of the scanning delay plus the scanning duration, up to 125 mL. The scanning delay was determined with bolus tracking. Contrast enhancement was measured in the main pulmonary artery and the aorta. For each patient, the injected contrast medium volume per body weight index was calculated. Linear regression analysis was performed, and the Wilcoxon signed rank test was used to assess differences between 16- and 64-section CT., Results: A range of patient weights (45.3-153.0 kg) and contrast medium volumes (76-125 mL) were noted. The regression formula indicated that 1.2 mL per kilogram body weight of contrast medium was required to achieve 250 HU. The median scanning duration was shorter for 64-section CT than for 16-section CT (5.7 seconds vs 9.5 seconds, P < .001). Consequently, 64-section CT required 17.6% less contrast medium than did 16-section CT (85.4 mL vs 103.6 mL, P < .001). Median contrast enhancement in the pulmonary artery was 8.9% lower with 64-section CT than with 16-section CT (257.7 HU vs 282.9 HU, P = .11)., Conclusion: To achieve consistent contrast enhancement during pulmonary CT angiography, the amount of contrast medium can be adjusted to the patient's body weight., ((c) RSNA, 2007.)

Objective: The objective of our study was to describe hybrid peripheral (HyPer) 3D contrast-enhanced MR angiography (CE-MRA) using sagittal acquisition with parallel imaging of the calf and foot station. The benefit of a dedicated sagittal 3D CE-MRA acquisition of the calf and foot was evaluated by assessing the degree of venous contamination and its diagnostic quality compared with standard bolus chase 3D CE-MRA alone., Materials and Methods: Fifty-three patients (99 legs) were scanned with a 1.5-T MR system equipped with a dedicated bilateral lower extremity phased-array coil. First, high-resolution 3D CE-MRA images of the calves and feet were obtained using two separate sagittal slabs with parallel imaging, with a resulting voxel size of 1.4 x 1.0 x 1.0 mm3. Second, standard bolus chase 3D CE-MRA was performed from the abdomen and pelvis station to the calf-foot station. Images were interpreted by two radiologists. The calf-foot arterial trees were divided into 12 segments. Each segment was characterized as diagnostic or nondiagnostic. The degree of venous contamination was assessed as interfering with the diagnosis or not. Paired Student's t test and Wilcoxon's signed rank test were used to test for statistically significant differences between the techniques., Results: For the left leg (n = 48), the mean number (+/- SD) of diagnosed arterial segments for HyPer 3D CE-MRA was 9.2 +/- 2.3 and for bolus chase 3D CE-MRA, 7.1 +/- 4.2 (p < or = 0.0004). For the right leg (n = 51), the corresponding values were 9.4 +/- 2.2 and 7.6 +/- 3.5 (p < or = 0.0005), respectively. For bolus chase 3D CE-MRA, venous contamination interfered with the diagnosis in 24 of 99 legs, whereas with HyPer 3D CE-MRA, there was no interference. Selective analysis of the dorsalis pedis arteries showed that the number of diagnostic vessels was 62 (62.6%) of 99 for HyPer 3D CE-MRA and 13 (13.1%) of 99 for bolus chase 3D CE-MRA., Conclusion: HyPer 3D CE-MRA is an alternative method for time-resolved high-resolution peripheral CE-MRA in evaluating the trifurcation and feet vessels with no venous contamination.

The anthropological record indicates that we are exposed to considerably less ultraviolet radiation (required for the synthesis of vitamin D) and consume considerably less calcium than did our early ancestors. Most U.S. citizens have calcium intakes and serum levels of vitamin D far below recommended values. This is despite there having been extensive evidence that optimal calcium and vitamin D intakes not only benefit our postcranial bone health but also have many other health benefits. Numerous articles indicate that vitamin D and calcium deficiencies result in bone loss and increased inflammation, which are well recognized symptoms of periodontal disease. For more than 40 years, investigators have suggested that calcium intake may be associated with alveolar bone resorption, and more recently there have been a number of studies in which investigators have suggested that calcium and vitamin D may benefit periodontal health, and it has been suggested that calcium deficiency may be a risk factor for periodontal disease. There has not, however, been a vitamin-D-calcium-periodontitis clinical trial in which randomization and masking were carefully controlled, the periodontal disease status of patients known, periodontal disease measures were the primary outcomes, and levels of intake optimized to produce maximal effects. Such research might demonstrate that calcium and vitamin D are important adjuncts to standard treatments for preventing and treating periodontal disease.

Purpose: To compare computed tomographic (CT) window settings selected by radiologists with those determined by using two alternative approaches for depiction of pulmonary emboli (PE)., Materials and Methods: Institutional review board approval was obtained; informed consent was not required. This study was compliant with the Health Insurance Portability and Accountability Act. Twenty-five clinical chest CT studies were obtained with a standardized PE protocol and retrospectively evaluated by five chest and two body CT radiologists. Of these studies, 13 were positive for PE, and 12 were negative. At the main pulmonary artery (PA), mean attenuations (MPA) and standard deviations (SDPA) were measured. Initially, images were displayed with a standard mediastinal window setting (window width, W = 400 HU; window center, C = 30 HU), and each observer adjusted the setting to a personally preferred setting (eg, "personal") for PE detection. Images displayed at this setting were compared in a side-by-side fashion with the "modified" (W = MPA + 2 . SDPA, C = W/2) and "double-half" (W = 2 . MPA, C = MPA/2) window setting. Each observer rated images from 1 (ie, most preferred) to 3 (ie, least preferred). For quantitative analysis, window width and center value of each setting were divided by corresponding MPA to compute a width ratio and a center ratio. Window settings and ratings were compared with repeated-measures analysis of variance, paired t tests, and Wilcoxon signed-rank tests., Results: Ratings for all three types of window settings were significantly different (P < .001). Observers preferred their personal settings the most and the modified settings the least. Mean ratios for the seven observers were 1.68 +/- 0.20 for window width and 0.47 +/- 0.08 for window center. Window width ratios for all settings were significantly different from each other (P < .001). Window center ratios were significantly higher for the modified setting than for the double-half setting (P = .013). Values for mean PA attenuation were correlated with window width ratios for six (86%) observers (mean r2 value = 0.29 +/- 0.19, P < or = .03) and with window center ratios for four (57%) observers (mean r2 value = 0.16 +/- 0.14, P < or = .02), thus indicating a trend of setting window width and window center higher when contrast enhancement is lower and vice versa., Conclusion: On average, observers selected CT window settings for PE detection at a window width of slightly less than twice the mean PA attenuation and at a window center of about half the mean PA attenuation. Observers tended to use larger window widths and centers as the degree of PA enhancement was lower.

Objectives: We sought to evaluate spectroscopic measurements in breast cancer and compare variability in choline peak parameters related to contrast administration versus that inherent to repeated measurements., Materials and Methods: Single-voxel, proton spectroscopy measurements were obtained before and after the administration of gadolinium on 15 patients with > or = 1-cm breast cancers. The protocol was repeated on a separate day in 7 patients., Results: Postcontrast spectra demonstrated a significant increase in choline peak linewidth (day 1: 15% +/- 21%, P = 0.03; day 2: 19% +/- 12%, P = 0.001) and decrease in choline peak area (day 1: 11% +/- 9% (P < 0.001); day 2: 18% +/- 21% (P = 0.03). A variance-components analysis indicated that day-to-day variation in linewidth accounted for 0.0% of the total variation in width measurements and was not significant (P = 0.85). Day-to-day variation in area was also not significant (0.0%, P = 0.95)., Conclusions: Contrast administration caused significant increases in choline peak linewidth and decreases in choline peak area in spectroscopic measurements of breast cancer.

Objectives: To devise and test for reproducibility a new patient-beam alignment device for subtraction radiography., Methods: A rigid, cross-arch bar was used with bite-registration material. A modified Rinn XCP rod and ring were firmly attached to the bar and were placed in contact with the X-ray cone. The receptor was held by a slot in the bar. Duplicate sets (n=8 pairs) of digital radiographs were made with a modified, calibrated DenOptix photostimulable phosphor system. Image pairs were registered and compared for geometrical and intensity errors by means of quantitative subtraction radiography. The reproducibility of patient-beam alignment for each pair was determined by measuring spatial errors at alveolar crest edges and by comparing magnifications. Intensity errors measured at two predetermined regions of alveolar bone were used to estimate corresponding bone-mass errors., Results: Misalignment at the alveolar crest was generally <1 pixel (0.085 mm), and everywhere < or =0.25 mm. The magnification was constant within a relative standard deviation of 0.13% (n=8). Trabecular features were generally invisible or barely visible in subtraction images. The standard deviation of intensity errors was 1.07% (n=16). This corresponds to a change in bone mass of approximately 2% or less., Conclusion: The device has potential for clinical population studies in which the goal is to detect small changes in bone mass and alveolar-crest height. It is convenient to use and comfortable for patients. Because of the cross-arch design, patient-beam alignment is expected to be relatively insensitive to bite-registration errors, tooth movement, and tooth loss.

Purpose: To evaluate the effect of various multi-detector row computed tomographic (CT) reconstruction parameters and nodule segmentation thresholds on the accuracy of volumetric measurement of synthetic lung nodules., Materials and Methods: Synthetic lung nodules of four different diameters (3.2, 4.8, 6.4, and 12.7 mm) were scanned with multi-detector row CT. Images were reconstructed at various section thicknesses (0.75, 1.0, 2.0, 3.0, and 5.0 mm), fields of view (30, 20, and 10 cm), and reconstruction intervals (0.5, 1.0, and 2.0 mm). The nodules were segmented from the simulated background lung region by using four segmentation thresholds (-300, -400, -500, and -600 HU), and their volumes were estimated and compared with a reference standard (measurements according to fluid displacement) by computing the absolute percentage error (APE). APE was regressed against nodule size, and multivariate analysis of variance (MANOVA) was performed with APE as the dependent variable and with four within-subject factors (field of view, reconstruction interval, threshold, and section thickness)., Results: The MANOVA demonstrated statistically significant effects for threshold (P = .02), section thickness (P < .01), and interaction of threshold and section thickness (P = .04). The regression of mean APE values on nodule size indicates that APE progressively increases with decreasing synthetic nodule size (R2 = 0.99, P < .01)., Conclusion: For accurate measurement of lung nodule volume, it is critical to select a section thickness and/or segmentation threshold appropriate for the size of a nodule., (Copyright RSNA, 2005.)

Objectives: To provide an overview of radiographic film holders, from their inception in the early 1900s to present day., Methods: A Medline literature search was conducted for dental studies that used keywords that pertain to radiographic film holders. Hand searches of the bibliographies were also conducted. Sixty articles (dating from 1896 to 1998) that describe new or improved film holders are reviewed here., Results: From the earliest days of dental radiography, dentists attempted to standardize radiographic images and techniques. The focus of researchers in the 1950s to the 1970s was to develop a film holder that would hold the film and allow easy and predictable alignment of the X-ray tube. As research projects became more dependent on dental radiographic measurements, the focus shifted to producing reproducible radiographic images, from which highly repeatable measurements could be made., Conclusion: Existing devices have strengths and weaknesses. Readily available devices are adequate for routine clinical use; however, user-friendly and patient-friendly film-holding devices that result in highly reliable and accurate measurements have yet to be introduced.

Surveys for assessing outcomes of spine surgery are typically cumbersome and require statistical analyses, which make their use impractical in nonacademic settings. The objective of this study was to develop a short pain survey (SPS) to assess patient satisfaction following spinal surgery and to compare the results with those of the Brief Pain Inventory-Short Form (BPI-SF), which is widely used in academic settings. Patients (n = 101) completed the BPI-SF prior to spinal fusion. Six months after surgery, patients completed the BPI-SF and SPS. Marginal homogeneity tests and paired t tests of the BPI-SF indicated highly significant (p < .001) postoperative improvements. One-sample binomial tests and Blyth-Still-Casella 95% confidence intervals also indicated highly significant (p < .001) postoperative improvements with SPS. There was a highly significant congruence (p < .002) between the responses for the two surveys. It was concluded that the SPS can be easily used in nonacademic settings to assess patient satisfaction and clinical success following spine surgery.

Objective: MRI and sonography are both used to evaluate patients with painful shoulders. This study was conducted to compare patients' perceptions and satisfaction with both tests., Subjects and Methods: One hundred eighteen patients with shoulder pain and a clinically suspected rotator cuff tear underwent both MRI and sonography and filled out satisfaction surveys after both tests. Patients were asked the following questions: Did the test cause pain? If it did, they were asked to grade the pain on a scale of 1-10 (1, minimal pain; 10, severe pain). Did the test take too long? Would they be willing to undergo the test again? How would they grade their overall satisfaction with the test (1, poor; 2, fair; 3, good; 4, very good; and 5, excellent)? Which test did they prefer if both were equally accurate?, Results: Sonography caused pain above the baseline in 39 patients, with an average pain score (mean +/- SD) of 5.4 +/- 2.3, and MRI caused pain above the baseline in 40 patients, with an average pain score of 6.1 +/- 2.7 (p = 0.36). Two patients thought the sonography examination took too long, and 28 patients though the MRI examination was too long (p < 0.001). The average satisfaction level for sonography was 4.3 +/- 0.7 and for MRI, 3.6 +/- 1.2 (p < 0.001). The satisfaction score was higher for sonography in 54 patients, higher for MRI in 13 patients, and the same for both in 50 patients (p < 0.001). All patients were willing to repeat the sonography, but 10 patients were unwilling to repeat the MRI (p = 0.002). Ninety-three patients preferred sonography, eight patients preferred MRI, and 17 patients had no preference (p < 0.001)., Conclusion: Most patients with shoulder pain prefer sonography to MRI.

Background: We have previously reported that estrogen/hormone replacement therapy (E/HRT) has beneficial effects on oral bone density over 3 years and that calcium and vitamin D supplementation has a lesser effect. Here we report on mandibular bone mass for 49 women (of the original cohort of 135) who continued in an additional 2-year, open-label extension., Methods: Postmenopausal women were randomly assigned to receive calcium and vitamin D plus E/HRT, or calcium and vitamin D only. Regression analysis of mandibular bone mass over time was performed for each woman., Results: Twenty-two of 26 women who took calcium and vitamin D plus E/HRT for 5 years had small mandibular bone mass increases (0.35 +/- 0.38%, P<0.001). Seventeen of 19 women who took only calcium and vitamin D for 3 years had increases in mandibular bone mass (0.74 +/- 0.89%, P<0.002). The largest gains in mandibular bone mass occurred during the first 3 years of the study., Conclusions: The data of this study indicate that E/HRT and/or calcium and vitamin D may result in increases of mandibular bone mass in postmenopausal women. Because of the long-term risks associated with E/HRT, caution should be exercised in prescribing E/HRT for prevention of chronic menopausal conditions.

Purpose: Although several articles have described the sonographic features of solid and cystic lesions of the hand and wrist, few have investigated its accuracy for diagnosing such lesions. The purposes of this retrospective study were to determine the accuracy of sonography for diagnosing focal lesions of the hand and wrist against the standard of histologic examination of the resected specimen and to compare the accuracy of sonography against the recorded initial clinical impression., Methods: A medical record search for all sonographic studies of the hand and wrist at our institution was performed. Eighty-four patients had correlative surgery and made up the study group. All sonogram reports were reviewed for the absence or presence of focal lesions and specific diagnoses and all medical records were reviewed for the initial clinical impression. Both were compared with histologic findings and tested for agreement with the kappa statistic and for significant differences with the McNemar test, Results: Seventy-six of the 84 patients had focal lesions of the hand and wrist and 8 had normal sonograms. Overall, ultrasound correctly diagnosed 83% of the lesions and the initial clinical impression was correct in 54%. Of the 76 lesions ultrasound correctly diagnosed 87% of cystic lesions, 73% of solid lesions, 75% of tenosynovitis cases and the single-vessel thrombosis. The initial clinical impression was correct in 67% of cystic lesions and 75% of tenosynovitis cases. The solid or cystic nature of the 15 solid lesions and the single-vessel thrombosis could not be determined by history or physical examination alone. Of the 35 cases in which the recorded clinical impression was incorrect or not recorded ultrasound provided the correct diagnoses in 71% of these cases. Agreement with the kappa statistical analysis was only fair and the recorded initial clinical impression was less accurate than ultrasound., Conclusions: Ultrasound was statistically more accurate than the initial clinical impression for distinguishing solid from cystic lesions of the hand and wrist. Ultrasound was very accurate for specifically diagnosing ganglions and slightly less for solid lesions and tenosynovitis.

Background: Although many investigators have evaluated the accuracy of ultrasonography and magnetic resonance imaging for the detection of full and partial-thickness rotator cuff tears, few have directly compared the two tests. The purpose of our study was to compare the accuracy of the two tests for detection and measurement of the size of rotator cuff tears, with arthroscopic findings used as the standard., Methods: One hundred and twenty-four consecutive patients with shoulder pain were prospectively studied with ultrasonography and magnetic resonance imaging. Seventy-one had subsequent arthroscopy, and they formed the study group. The arthroscopic diagnosis was a full-thickness tear in forty-six patients, a partial-thickness tear in nineteen, and no tear in six. The presence or absence of a full or partial-thickness tear and the tear size as demonstrated by each imaging test and at the time of arthroscopy were recorded. The findings of the imaging tests and arthroscopy were then compared for each parameter., Results: Ultrasonography correctly identified forty-five of the forty-six full-thickness tears and magnetic resonance imaging, all forty-six. Ultrasonography correctly identified thirteen of the nineteen partial-thickness rotator cuff tears and magnetic resonance imaging, twelve of the nineteen. The overall accuracy for both imaging tests was 87%. Ultrasonography correctly predicted the degree of retraction of 73% of the full-thickness tears and the length of 85% of the partial-thickness tears, and magnetic resonance imaging correctly predicted the retraction and length of 63% and 75%, respectively. Ultrasonography correctly predicted the width of 87% of the full-thickness tears and 54% of the partial-thickness tears, and magnetic resonance imaging correctly predicted the width of 80% and 75%, respectively. No significant differences between ultrasonography and magnetic resonance imaging were demonstrated (p > 0.05)., Conclusions: Ultrasonography and magnetic resonance imaging had comparable accuracy for identifying and measuring the size of full-thickness and partial-thickness rotator cuff tears. When an investigator has comparable experience with both imaging tests, the decision regarding which test to perform for rotator cuff assessment does not need to be based on accuracy concerns. The choice can be based on other factors, such as the importance of ancillary clinical information (regarding lesions of the glenoid labrum, joint capsule, or surrounding muscle or bone), the presence of an implanted device, patient tolerance, and cost.

Objective: The objective of our study was to compare accuracies of axial, multiplanar, and 3D volume-rendered images in the diagnosis of thoracic aortic anomalies in pediatric patients and young adults., Materials and Methods: Fourteen patients, 17 days to 20 years old, with thoracic aortic anomalies underwent MDCT using axial, multiplanar, and 3D volume-rendering imaging. All images were reviewed by three radiologists for position of the aortic arch, coarctation, vascular compression of the airway, collateral vessel formation, and aortopulmonary shunts (patent ductus arteriosus). Final diagnosis was determined by echocardiography, conventional angiography, bronchoscopy, or surgery. Diagnostic accuracy, sensitivity, and interobserver agreement were evaluated., Results: Average accuracies (average of the three observers for a correct diagnosis) were greater than or equal to 96% for diagnoses of aortic position and airway narrowing on all image types. For the diagnosis of coarctation, average sensitivities (average of the three observers for a true diagnosis) were 73% for axial, 100% for multiplanar, and 100% for 3D volume-rendered images. For the diagnosis of patent ductus arteriosus, average sensitivities were 78% for axial, 94% for multiplanar, and 89% for 3D volume-rendered images. No patients in this study had collateral vessel formation. For the diagnosis of absence of collateral vessel formation, average sensitivities were 100% for axial, 100% for multiplanar, and 100% for 3D volume-rendered images. There were no significant statistical differences in diagnostic performances, agreement with truth, or confidence scores among observers or imaging formats (p > 0.05)., Conclusion: Axial, multiplanar, and 3D volume-rendered images serve equally well as methods for assessing the side of the aorta to diagnose anomalies. For evaluation of coarctation and patent ductus arteriosus, multiplanar and 3D volume-rendered images perform slightly better than axial images.

Objectives: To determine whether alveolar trabecular bone is visible and quantifiable in projection radiographs. Radiographic changes in oral trabecular bone have been studied as possible indications of bone loss, but in some previous studies, observed structures have been attributed entirely to the endosteal surface., Methods: Computed radiography (CR) images of human mandibles in molar and pre-molar regions were compared with simulations calculated from high-resolution computed-tomography (CT) and micro-CT volumes. By digitally editing the CT volumes, the simulations were separated into trabecular and cortical components. High-pass-filtered CR images revealed structural details of cortical and trabecular bone., Results: Trabecular bone constitutes as much as 38% of the total alveolar bone, and accounts for most of the observed alveolar fine structure. Several morphological types of fine structure can be distinguished. The noise in filtered images appears to be a meaningful measure of trabecular bone., Conclusion: Trabecular bone is highly visible in intraoral radiographs.

Background: The purpose of this study was to investigate the source of radiographic trabecular patterns by removing trabecular bone in four sequential steps from six cadaver mandible sections, radiographing the sections after each removal, and using four digital-image analysis methods to quantify any resulting changes to the radiographs., Methods: Mandible sections were cut sagittally into halves. Trabecular bone was removed from each section in four stages. Following each stage, standardized radiographs were taken, using direct digital equipment. Trabecular bone in the resulting digital images was measured with four methods. Mean gray level values (method 1) and cumulative percent histograms (method 2) were calculated from the raw data. Morphological image processing was used to skeletonize the trabecular structure, which was quantified by counting the number of trabecular ends and segments in the skeletonized images (method 3) and performing fractal analyses of the skeletonized images (method 4). Repeated measures analysis of variance (ANOVA) was used to test for changes in measurements attributable to bone removal., Results: Repeated measures ANOVA indicated that the use of gray levels, cumulative percent histograms, and morphologic operators resulted in highly significant changes in measurements following bone removal (P < 0.01). Ends and segments demonstrated similar performance, with changes highly significant over time (P < 0.01). Fractal analysis also resulted in highly significant changes over time (P < 0.01)., Conclusions: The analyses performed in this study demonstrated consistent image differences following the four steps of bone removal. These differences appeared whether light, cancellous bone or heavier endosteal bone was removed. These findings indicate that trabecular and endosteal bone combine to form the structure that most dentists identify as trabeculae on intraoral radiographs.

Objective: We assessed the ability of high-resolution sonography to reveal the size and echogenicity of the anterior bundle of the normal medial collateral ligament of the elbow in cadavers and uninjured male volunteers., Materials and Methods: The anterior bundle of the medial collateral ligament in five cadaveric elbows was imaged and injected with contrast material by experienced musculoskeletal radiologists using a 12-MHz linear array transducer. Immediate ligament dissection was performed. The bilateral ligaments in 30 healthy 21- to 34-year-old male volunteers were imaged with gravitational stress. Of these, five randomly selected subjects also received approximately 5 lb (11.3 kg) of applied stress., Results: Contrast material was injected directly into all five cadaveric ligaments. The anterior bundle of the medial collateral ligament in all 30 asymptomatic male volunteers was hyperechoic in comparison with surrounding muscle and had a fibrillar pattern and fanlike shape. Its mean dimensions were 2.6 +/- 0.31 x 2.2 +/- 0.47 x 4.0 +/- 0.88 mm on the right and 2.6 +/- 0.36 x 2.1 +/- 0.42 x 4.0 +/- 0.86 mm on the left, in longitudinal short, transverse short, and transverse long axes, respectively. Differences in ligament measurements in sidedness, stress application, and hand dominance did not approach statistical (Bonferroni corrected, p > 0.01) or clinical (all differences, <0.2 mm) significance., Conclusion: Radiologists can accurately use sonography to identify and measure the size of the anterior bundle of the normal medial collateral ligament of the elbow. These baseline parameters for the normal ligament may prove useful when evaluating the injured ligament.

Background: The loss of ovarian function at menopause is associated with loss of postcranial and oral bone. Hormone/estrogen replacement therapy (HRT/ERT) has a positive effect on both postcranial and oral bone. The objective of the study was to determine if the positive effect of HRT/ERT on alveolar crest height (ACH) is generalized or site specific., Methods: The sample consisted of 49 women who completed a 3-year, HRT/ERT prospective study. Cemento-enamel junction distances (ACH) were measured on digitized images of bitewing radiographs. Lumbar spine and proximal femur bone mineral densities (BMDs) were determined with dual-energy x-ray absorptiometric scans. Measurements were made at baseline and at the end of year 3. For the 3-year study period, mean change in ACH was determined for each patient. In addition, the sites with the greatest, second and third greatest ACH changes were determined for each patient. Correlations between changes in ACH (as determined by the various methods) and postcranial BMD were determined., Results: Mean ACH changes had an average correlation (r) of -0.24 with femoral and lumbar spine BMDs. Although the largest site-specific change in ACH resulted in a mean correlation of -0.21, the correlations for the second and third largest changes in ACH dropped to -0.15 and -0.12. Overall, the correlations for site-specific changes were substantively smaller than those for generalized change., Conclusions: The data of this study indicate that ACH change attributable to HRT/ERT is generalized rather than site specific. Studies of the effect of HRT/ERT on ACH should employ multiple measurements to minimize measurement errors associated with site-specific measurements.

Background: There are physiological reasons to expect an association between bone mineral density of the spine and hip and attachment loss. To this point, however, most studies have found no correlation., Methods: The 135 patients in this report were part of a randomized controlled trial of estrogen replacement. All patients were in good oral health at entry and received annual oral prophylaxis as part of the study. Standard probing measurements were made with a pressure sensitive probe at 6 sites on each tooth. Bone mineral density was measured with dual-energy x-ray absorbtiometry at the lumbar spine (anterior-posterior and lateral) and proximal femur (neck, trochanter, intertrochanter, Ward's triangle, and total area). These procedures were performed at baseline and at annual intervals for 3 years., Results: Correlations between cross-sectional measurements of clinical attachment level and bone mineral density were very weak, and did not approach statistical significance (-0.06 < or =r < or =0.10, 0.15 < or =P < or =0.75). A few somewhat stronger correlations were found between longitudinal changes in bone mineral density and attachment (-0.20 < or = r < or =-0.02, 0.02 < or = P < or =0.81). Although the correlations in the longitudinal changes were weak, they were consistently in the direction of greater bone mineral density being associated with less attachment loss., Conclusions: There is no clear association between clinical attachment level and bone mineral density of the lumbar spine and proximal femur, whether examined on a cross-sectional or longitudinal basis. Patterns in the data suggest there may be a weak association in the longitudinal changes.

Objective: To describe an extended bootstrap calibration procedure that uses a step-wedge absorber and minimal equipment for rapid, accurate calibration of image receptors and simultaneous monitoring of beam quality., Methods: Multiple radiographs of a step wedge are made at different exposures, with a precision dosimeter as a reference. An iterative least-squares minimization procedure is used to fit the data with a single calibration function. The calibration range can be extended by varying two exposure parameters in addition to stepwedge thickness. Small variations in beam quality and other experimental artifacts can be detected by testing redundant data for self-consistency. As a demonstration, two photostimulable phosphor (PSP) systems were calibrated, one with a well-regulated X-ray source and the other with a poorly regulated source., Results: The first PSP system was calibrated over a range of 3.2 orders of magnitude with a relative standard deviation of the estimate of only 0.36%. The slope of the calibration curve agreed with the nominal, factory-set value within 0.8% (on a logarithmic scale). The second PSP system had a nearly linear response with a relative standard deviation of the estimate of 0.44% over the upper 97% of its range. Both X-ray sources showed easily detectable variations in tube potential., Conclusions: The new calibration method eliminates many of the sources of error of previous techniques such as inverse-square sensitometry. If a suitably precise X-ray source is available, the relative accuracy is limited only by the precision of the receptor system.

Objective: To assess the sonographic findings of breast masses in adolescents and the usefulness of sonographic patterns for suggesting a specific diagnosis., Methods: The sonograms and medical records of 57 girls (mean age, 15.4 years) with palpable breast masses were retrospectively reviewed. Three observers reviewed the sonograms for multiple sonographic findings. Surgery or clinical findings established diagnoses. Statistical analysis was done to determine how well sonographic findings alone and in combination agreed with final histologic diagnoses., Results: Diagnoses included cysts (n = 12), abscesses (n = 7), fibroadenomas (n = 36), a lactating adenoma (n = 1), and a phyllodes tumor (n = 1). The sonographic findings varied significantly among lesion types (P < or = .005)., Conclusions: Our experience suggests that virtually all breast masses in a pediatric population are benign and that sonography has the ability to differentiate among cystic, inflammatory, and solid masses.

Objectives: To determine if variations in radiodensity data are introduced by lossy Joint Photographic Experts Group (JPEG) compression and/or the use of three software programs., Methods: An occlusal film with an aluminium step wedge was exposed, processed and digitized under standard conditions. Before the image was saved, the coordinates and the gray-scale value for each pixel in a 20 x 20 pixel area near the middle of the thickest step were recorded. These pixel coordinates and gray-scale values served as Truth 1. In addition, a digital simulated-radiographic image with assigned gray-scale values for each pixel was created and served as Truth 2. The digital data for the scanned radiograph and the simulated radiograph were saved as Tagged Image File Format (TIFF) and lossy JPEG files. Each file was opened with three software programs and the gray-scale values of homologous pixels were recorded. For these pixels in each image type, the mean gray-scale values and standard deviations were calculated. The pixel gray-scale values for each homologous pixel were also individually compared., Results: When the TIFF images were opened with the three software programs, one program resulted in gray-scale values that were not concordant with truth. All JPEG images resulted in gray-scale values that were not concordant with truth., Conclusions: One software program added a column of 0s to data files. Lossy JPEG compression introduced potentially deleterious variations to radiodensity data, and at least two of the software programs performed JPEG image decompression differently.

This study was undertaken to determine whether ferric ammonium citrate (FAC), a positive magnetic resonance (MR) contrast agent, is of clinical value in demonstrating or excluding pathology of the upper gastrointestinal tract. A retrospective review was performed of pre- and post-FAC studies of MR examinations in 203 patients from phase II and III clinical trials in whom final diagnoses had been established based on the results of biopsy, surgery, or independent imaging procedures. Two independent reviewers made randomized and blinded assessments of the stomach, duodenum, and pancreas. FAC significantly increased the certainty of diagnosis for normal studies of the stomach and duodenum for both readers (P < 0.001) and for abnormal studies of the stomach for one reader (P = 0.004). FAC also significantly increased the certainty of diagnosis for normal pancreas for one reader (P < 0.001). FAC significantly (P < 0.001) increased accuracy and specificity for diagnoses involving the stomach and duodenum for both readers and for one reader for the pancreas. There was significant improvement in sensitivity for gastric diagnoses (P = 0.013) for one reader but not for the duodenum or pancreas. We conclude that FAC is helpful in demonstrating and excluding upper gastrointestinal pathology on MR.

Background: This study was undertaken to compare 5 digital analytic protocols for their abilities to extract data from digital clinical radiographs and discriminate between patients with gingivitis and periodontitis., Methods: Five digital-image analysis protocols were compared for their abilities to discriminate between two groups of 24 patients each. One group was diagnosed with healthy gingiva (or gingivitis) and the second with periodontitis. These groups were previously evaluated in published studies that used fractal and morphologic analyses. Pre-existing clinical radiographs for each patient were digitized and regions of interest (ROIs) were placed on interdental bone in mandibular posterior quadrants. The 5 protocols used were: 1) MGB: a median filtration to remove high-frequency noise, a Gaussian filtration to remove low-frequency noise, binarization of the resulting image, and quantification of the black pixels; 2) MGBS: the same protocol as MGB except for a skeletonization of the binary image and a quantification of the skeleton's pixels; 3) GBS: Gaussian filtration, binarization (thresholding on the mean pixel value) of the resulting image, skeletonization, and quantification of the pixels of the skeleton; 4) NS: normalization, skeletonization, and quantification of the skeleton's pixels; and 5) S: a variation of NS, except normalization was not used. The resulting values for the 2 patient groups were compared with Mann-Whitney U tests and effect likelihood-ratio test., Results: For digitized radiographs, the mean gray-scale value (+/- standard deviation) for gingivitis patients was 183.22 +/- 18.53 and for periodontitis patients 181.26 +/- 17.20. Mann-Whitney U tests resulted in the following P values for these protocols: MGBS <0.01; S <0.01; GBS <0.01; NS <0.01; and MGB <0.83. Effect likelihood-ratio tests indicated that only MGBS and S significantly contributed to models containing the other factors., Conclusions: Small variations to protocols affected the strength of the discrimination between the gingivitis and periodontitis groups. While there is potential for morphologic analysis to be used to discriminate between patients with gingivitis and periodontitis, a robust technique was not identified.

This study was undertaken to identify differences in the sonographic appearance of acute and chronic full-thickness rotator cuff tears. The ultrasonograms of 24 patients with an acute rotator cuff tear and 20 with a chronic tear were reviewed for tear size (width), location, and the presence and distribution of fluid. Among these 24 patients, 75% with a midsubstance tear location had an acute tear; 64% of patients with joint or bursal fluid had an acute tear; 80% of patients with a nonvisualized rotator cuff due to a massive tear had a chronic tear; and 73% of patients with no sonographic evidence of bursal or joint fluid had a chronic tear. In conclusion, a midsubstance location and the presence of joint or bursal fluid were more commonly associated with an acute tear. A nonvisualized cuff and the absence of joint and bursal fluid were more commonly observed with a chronic tear.

Objective: To determine the cross-sectional and longitudinal relationships between radiographic alveolar bone height and probing attachment level in a population of healthy postmenopausal women., Materials and Methods: The 81 patients in this report were part of a prospective estrogen replacement interventional study. All patients were in good oral health at entry and received annual oral prophylaxis as part of the study. Standard probing measurements were made with a pressure sensitive probe at 6 sites on each tooth. Vertical bitewing radiographs were digitized, and 6 linear measurements corresponding to probing-site measurements were made from the cementoenamel junction to the alveolar crest. These procedures were performed at baseline and at annual intervals for three years. Data were analyzed both by site and by patient., Results: Moderately strong correlations were found between cross-sectional measurements of probing attachment height and radiographic bone height. Correlations were stronger for patient data (r=0.44-0.61) than for site data (r=0.19-0.36). No relationships were found between longitudinal changes in alveolar bone height and attachment level in either the site data (r=-0.10-0.04). or the patient data (r=-0.005-0.10)., Conclusion: Healthy patients may experience sporadic, temporary changes in attachment level or alveolar bone height which are resolved without one affecting the other.

Background: Our objective was to test the association between cemento-enamel junction, alveolar-crest distance (CEJ-AC, as measured on digitized vertical bite-wing radiographs) and postcranial bone mineral density (BMD) relative to clinical, dietary, and demographic variables., Methods: Data were collected in a cross-sectional study of 134 postmenopausal women. CEJ-AC distances were determined from digitized vertical bite-wing radiographs. Lumbar spine and proximal femur BMDs were determined from dual-energy x-ray absorptiometric scans. Correlation analysis and Student t tests were used to identify those variables most associated with CEJ-AC distance. The selected variables were modeled with a backward stepwise regression analysis, with CEJ-AC distance as the dependent variable., Results: Parity (number of pregnancies to term), cigarette smoking, and the interaction of lateral spine BMD with cigarette smoking were independent predictors of CEJ-AC distance (P < or =0.05). Statistical models containing these variables accounted for 19% of the variation in CEJ-AC distances., Conclusions: CEJ-AC distance in postmenopausal women is the result of a complicated interaction of many effects, including but not limited to, parity, cigarette smoking, and skeletal BMD.

Photostimulable phosphor radiography (PPR), a mature industry in medical imaging, became available in dentistry in 1994. At least three dental PPR systems have been made available commercially since that time. Although dental PPR offers a number of advantages over film-based methods, some aspects of dental PPR need improvement. Further research is needed to more fully compare and contrast this modality with film-based methods.

Background: We set out to determine whether morphologic measurements extracted from digitized images of bite-wing radiographs correlated with lumbar and femoral bone mineral density (BMD) measurements in 45 postmenopausal women who had no or only mild periodontal disease (no probing depths >5 mm)., Methods: Lumbar spine and femoral BMDs were determined by dual-energy x-ray absorptiometry. Vertical bite-wing radiographs were taken and digitized. Crestal and apical regions of interest (ROIs) were drawn on the digital images of the maxillary and mandibular alveolar bone on the patient's right and left sides. For each patient, a single morphologic measurement was made for each of 8 ROIs. Correlation analysis was performed to determine the strengths of the relationships between the morphologic measurements made at the 8 locations and between these morphologic measurements and BMD measurements., Results: The correlations (r) between the morphologic operator (MO) measurements and lumbar spine and femoral BMDs were weak (mean r = 0.02, range = 0.32 to -0.26) and not statistically significant, with no clear trends discernible. Correlations between MO measurements made at the 8 alveolar sites were also weak (mean r = 0.05, range = 0.35 to -0.38) and not statistically significant., Conclusions: The MO measurements used in this study were weakly correlated with lumbar spine and femoral BMDs, with no clear trends discernible in this population of postmenopausal women with no or mild periodontal disease.

Purpose: To evaluate the diagnostic accuracy of primary and secondary magnetic resonance (MR) imaging findings of anterior cruciate ligament (ACL) tears in young patients with immature skeletal systems., Materials and Methods: MR images obtained in 43 patients aged 5-16 years who underwent arthroscopy were retrospectively reviewed. Two reviewers evaluated primary findings (abnormal signal intensity, abnormal course as defined by Blumensaat angle, and discontinuity), secondary findings (bone bruise in lateral compartment, anterior tibial displacement, uncovering of posterior horn of lateral meniscus, posterior cruciate ligament line, and posterior cruciate angle), and meniscal and other ligamentous injuries., Results: There were 19 ACL tears and 24 intact ACLs. Overall sensitivity and specificity of MR imaging in detecting ACL tears were 95% and 88%, respectively. Sensitivities of the primary findings were 94% for abnormal Blumensaat angle; 79%, abnormal signal intensity; and 21% discontinuity. The specificity of all primary findings was 88% or greater. The sensitivity and specificity of the secondary findings, respectively, were 68% and 88% for bone bruise; 63% and 92%, anterior tibial displacement; 42% and 96%, uncovered posterior horn of lateral meniscus; 68% and 92%, positive posterior cruciate line; and 74% and 71%, abnormal posterior cruciate angle. Fifteen (79%) patients had meniscal tears, and five (26%) had collateral ligament injuries., Conclusion: Primary and secondary findings of ACL tears in young patients have high specificity and are useful for diagnosis.

Purpose: To determine if computed radiography is equivalent to screen-film radiography in depicting pulmonary edema and to determine if radiation exposure can be reduced with computed radiography while maintaining equivalent diagnostic accuracy for pulmonary edema., Materials and Methods: Oleic acid was intravenously injected into three rabbits at each of four doses: 0, 0.02, 0.04, and 0.06 mL/kg. Two hours later, chest computed radiographs and screen-film radiographs were obtained at 60 kVp and 1.1 mAs. Additional computed radiographs were obtained after reducing milliampere seconds or by reducing milliampere seconds and increasing the kilovolt peak, which reduced bone marrow exposure by up to 20%. The presence of pulmonary opacities, "truth," was established by the wet-dry weight ratio and by chest computed tomography (CT). The radiographs were masked and randomized. Four observers rated the images for the presence of parenchymal opacities with a dichotomous score and judged the quality of the radiographs on a scale from 1 (worst) to 6 (best). Cochran Q tests and McNemar tests were used to analyze the differences in paired comparisons. Image quality was evaluated with logistic regression analysis., Results: There was no significant difference between truth and observer ability to detect opacity for either modality or for any exposure (P > .05). There was no significant difference between computed radiography and screen-film radiography for image quality (P > .05)., Conclusion: Computed radiography is equivalent to screen-film radiography in the detection of pulmonary edema. Radiation exposure reduction of 20% can be achieved without affecting pulmonary edema detection or image quality.

Objective: To determine the correlations among morphologic operations (MO) values and the correlations among gray-level values for regions of interest (ROIs) placed at various locations on digital images of alveolar bone for 45 patients., Study Design: As part of a larger study, up to 7 vertical bite-wing radiographs were taken and digitized for each of 45 patients. Sets of 2 rectangular ROIs were placed on the digitized images of interdental alveolar bone at 4 locations for each patient. The ROIs (1 crestal and 1 apical) were placed between second premolars and first molars in all 4 dental quadrants. Gray-level values were measured, and MO analysis was performed on each ROI. Descriptive statistics were calculated and correlations determined., Results: Paired correlations (such as apical vs crestal, left vs right, maxillary apical vs mandibular apical) of MO values were weak (r = 0.01-0.21), but corresponding correlations for gray-level values were relatively strong (r = 0. 60-0.92)., Conclusion: MO values varied with ROI location considerably more than did gray-level values. Additionally, ROI size and shape apparently affected MO data. Accurate placement and documentation of ROIs appear to be critical considerations in analyses that use MOs.

The objective of this study was to create three-dimensional (3D) images for the histomorphological study of osteons. Medical imaging technology was used to register digitized 2D images of serial decalcified histological sections of bone, to segment the tissues of interest from the surrounding tissues, and to create 3D reconstructions from the segmented structures. Examination of the 3D reconstructions did not support suggestions in the literature that osteons have a spiraling organization. In contrast, the 3D reconstructions indicated that osteons have a complex pattern of organization that is dominated by branching. Examination of the reconstructions also suggested that osteons described in the literature as being dumbbell shaped are actually artifacts of the plane of sectioning. This study demonstrated the applicability of imaging and visualization technology developed for the 3D reconstruction of medical images to the reconstruction of digitized 2D images of serial sections of bone and additionally demonstrated the feasibility of using 3D reconstructions for the histomorphological study of osteons.

Background: The relationship between loss of radiographic alveolar bone height and probing attachment loss has been studied by a number of investigators, with mixed results. Recent studies have found weak correlations and have suggested that the relationship between bone loss and attachment loss is complex, perhaps because changes in bone height and attachment level are separated in time., Methods: The 85 patients in this report were part of a prospective estrogen replacement interventional study. All patients were in good oral health at entry and received annual oral prophylaxis as part of the study. Standard probing measurements were made with a pressure-sensitive probe at 6 sites on each tooth. Vertical bite-wing radiographs were taken of each patient, radiographs were digitized, and 6 linear measurements (corresponding to probing site measurements) were made from the cemento-enamel junction to the alveolar crest. These procedures were performed at baseline and at annual intervals; this study reports results after 2 years. Data were analyzed both by individual site and by averaging identical sites from all measured teeth for each patient., Results: Very weak direct relationships between change in alveolar bone height and change in attachment level were found in both the site data (r2=0.0022; P = 0.189) and the patient average data (r2=0.031; P= 0.104)., Conclusions: The changes in these patients were probably due to systemic changes in bone health rather than to periodontal disease. However, the weak correlations between changes in attachment level and bone height are similar to recent studies of periodontal disease. Our results support suggestions in the literature that the link between changes in attachment and alveolar bone height is complex, perhaps because changes in the 2 tissue types are separated by a considerable time delay.

Observer reliability in performing linear measurements between the cementoenamel junction and alveolar crest was determined for mandibular posterior teeth from digitized clinical bitewing radiographs acquired during recall examinations. 6 measurements (corresponding to traditional probing measurements) were made per tooth by 3 observers. Mesial and distal measurements made to the most coronal aspects of the alveolar crest were the most reliable and least biased. As was anticipated, intra-observer reliability was better than inter-observer reliability although the 3 observers of our study were able to detect a significant mean change (0.1 mm, p<0.0001) in alveolar bone height over a 1-year period for 10 patients. For our most reliable and unbiased measurements (mesial measurements to the alveolar crest), a change of 0.54 mm (90th percentile) would be required to indicate change at a site from one time to the next. Based on the reliability of our digital radiographic measurements, with the alpha error rate set at 0.05 and beta at 0.20, a difference in alveolar bone height of 0.3 mm could be detected with a patient sample size of between 13 (best case) and 54 (worst case).

Purpose: To characterize the thin-section computed tomographic (CT) appearance of bronchiolitis fibrosa obliterans syndrome in infants and young children after lung transplantation., Materials and Methods: Thin-section CT studies in six patients with bronchiolitis obliterans syndrome (age range, 2 months to 5 1/2 years) and in 15 control patients without obstructive airway disease (age range, 2 months to 7 years) who underwent bilateral lung transplantation were retrospectively reviewed. The thin-section CT scans were obtained during quiet sleep at a median of 24 months (range, 6-36 months) after transplantation. The CT studies were evaluated for mosaic perfusion, bronchial dilatation, bronchial wall thickening, and mucous plugging Final diagnoses in all patients were based pulmonary function test results., Results: Thin-section CT findings in the six patients with clinically proved bronchiolitis obliterans syndrome were mosaic perfusion in five (83%) bronchial dilation in three (50%), and bronchial wall thickening in one (17%). Of the 15 control patients with normal pulmonary function test results, six (40%) had mosaic perfusion; none had bronchial dilatation or bronchial wall thickening. Mucous plugging was not seen in either group. Only the association of bronchial dilatation with bronchiolitis obliterans syndrome was significant (P = .02)., Conclusion: Infants and young children with bronchiolitis obliterans syndrome after lung transplantation are more likely to have CT abnormalities than those with normal pulmonary function test results.

Objective: To compare the reliability of radiodensity measurements made from dental radiographs with manual and a novel computer-intensive methods., Methods: As part of a prospective study of postmenopausal women, a series of seven vertical bitewing radiographs were taken of 36 patients. One of each set of radiographs was repeated. The original and the corresponding duplicate radiographs were used in this study. Radiographs were digitized at 50 microns spatial resolution and 12-bit gray-scale resolution. For the Manual Method, original and duplicate radiographs were manually cropped to improve image homology, histogram matched and mean pixel gray-scale values determined for an alveolar bone ROI within each image. For the computer-intensive method, images were put into registration with ANALYZE software (Mayo Foundation, Rochester, MINN, USA), cropped automatically, histogram matched and color-coded on the basis of the per cent difference. Alveolar bone ROIs adjacent to clinical crowns and root surfaces whose color code indicated less than a 5% change were sampled. Method error (ME) and the coefficient of variation of method error (CVME) were calculated., Results: With the Manual Method the SD between original and duplicate measures was 95.21 out of 4096 gray scale values; ME = 67.32; CVME = 3.78%. For the computer-intensive method, the corresponding values were 54.74, 38.71, and 2.29%., Conclusions: The new computer-intensive method resulted in a 40% improvement over the Manual Method in the precision of radiodensity measurements.

Objectives: This study was conducted to determine whether morphologic operation procedures applied to digitized, non-standardized, clinical radiographs of mandibular alveolar bone could be used to distinguish between a population of patients diagnosed with periodontitis and a population of patients either diagnosed with gingivitis or having healthy gingivae., Study Design: Two groups, one consisting of 29 patients who either had healthy gingivae or had been diagnosed with gingivitis and the other consisting of 32 patients who had been diagnosed with periodontitis, were compared. Pre-existing clinical radiographs were digitized, and for each patient three to six regions of interest were placed on an image of the mandibular posterior region of the interdental bone. The regions of interest were processed under two morphologic-operations protocols, and a mean density (referred to as an MO number) was calculated for each patient. With paired t-tests, the resulting MO numbers for the two groups were compared., Results: The two populations were statistically different (p < 0.05)., Conclusion: The results of this study indicate that morphologic operations have the potential to differentiate between patient groups differing in periodontal health.

This study was undertaken to demonstrate that the fractal dimensions calculated using digitized non-standardized, clinical radiographs of mandibular alveolar bone from a population of patients diagnosed with periodontitis are statistically different from fractal dimensions calculated from another population diagnosed as having gingivitis or healthy gingiva. The fractal dimension was calculated using a public domain fractal analysis program distributed by the National Institutes of Health (NIH). Fractal dimensions were calculated from digitized clinical radiographs for 29 patients diagnosed with healthy gingiva and/or gingivitis and 32 patients diagnosed with periodontitis and compared. To estimate the reproducibility of the technique, we recalculated the fractal dimension from images of the gingivitis patients 3 months after the original calculations and compared them to the originals. A 2 sample, 2-tailed Student t test showed the gingivitis data group to be different from the periodontitis data group (P = 0.0012). The original gingivitis and repeat gingivitis groups fractal dimension calculation were the same and analysis showed the two data sets were not significantly different (P = 0.99). We found that: 1) fractal dimensions could be used to distinguish between gingivitis and periodontitis patient groups; 2) fractal dimensions could be calculated from non-standardized clinical radiographs; and 3) fractal dimensions for gingivitis patients were reproducible over a 3-month period.

Objective: Our purpose was to estimate the incidence of encephalopathy after transjugular intrahepatic portosystemic shunting (TIPS) related primarily to the diversion of portal vein blood flow and to identify periprocedural factors to predict patients at risk., Materials and Methods: All patients who underwent TIPS with at least 1 month of clinical observation after the procedure were monitored for clinically evident encephalopathy. Other variables that could individually induce encephalopathy were retrospectively analyzed for interrelationships with spontaneous or worsened encephalopathy., Results: Of the 150 patients, 68 (45%) suffered from encephalopathy after TIPS, but in only 33 (22%) was it new or worse than baseline measurements obtained before TIPS; in 18 of these 33 patients, an underlying medical cause was implicated. Fifteen (10%) of the 150 patients developed mental dysfunction, usually mild and well controlled, thought to be related only to TIPS and not to any underlying morbidity. Low portal vein pressures after TIPS were found to be interrelated with new or worsened spontaneous encephalopathy (p = .04). Like-wise, advanced age (> 59 years old) weakly corresponded to the development of encephalopathy after TIPS., Conclusion: TIPS causes an acceptably low rate of encephalopathy that is usually mild. No specific variables exist for predicting the development or progression of encephalopathy after TIPS.