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The ability of five low-dose mammographic screen--film systems to portray normal and abnormal breast structures was evaluated in parallel with a study of physical image properties. Single-blind evaluations of the visibility of normal breast architecture, mass lesions, and calcifications were made on the mammograms of 100 patients radiographed with each of the systems. There was increased noise and slightly poorer resolution for the faster recording systems, but there was no difference in final diagnostic impressions among the five systems. These results suggest that the faster systems will result in substantial dose reduction without sacrificing diagnostic accuracy.

The widely used DuPont Lo-dose mammography screen-film system was compared with four combinations of higher efficiency screens and single-emulsion films. Laboratory comparisons of the basic image properties (resolution, noise, contrast) of all these screen-film combinations were made both qualitatively (images of microwire meshes, tiny plastic beads, step wedges) and quantitatively (modulation transfer functions, Wiener spectra, step wedge optical density differences). Subjective single-blind estimations of resolution, noise, and contrast were also made directly from the mammograms of 100 consecutive patients radio-graphed with each of the five screen-film combinations. Both laboratory and clinical evaluations of image quality showed strikingly similar results: improved contrast, minimally reduced resolution, and varying degrees of increased noise for each of the high efficiency recording systems. Similarities between the results of laboratory and clinical studies should help to establish the clinical relevance of the laboratory analyses, and recognition of the relative precision of the clinical evaluations should allow for their use in place of laboratory studies when sophisticated physics support is not available.

Controlled in vitro studies of breast microcalcification detectability were accomplishedusing a wide variety of standard and state -of- the -art mammography techniques (conventionaland microfocal spot x -ray tubes, screen -film and xeroradiographic recording systems,contact and magnification techniques). Results confirm previous observations thatgeometric unsharpness is the limiting factor in microcalcification detectability for mostconventional mammography systems. Results also indicate superior microcalcificationdetection for: xeroradiographic > screen -film recording systems, positive -mode > negative -mode xeroradiography, microfocal spot contact > conventional contact techniques,microfocal spot magnification > contact techniques, and 2X magnification > 1.5Xmagnification techniques. Clinical applications of these findings are discussed.IntroductionRadiographic detection of breast microcalcifications having characteristic shape anddistribution is often crucial to the early diagnosis of breast carcinoma(1 -3). However,conventional mammography demonstrates microcalcifications in only 30 -50% of breastcancers(4 -6), while 60 -80% of these cancers can be shown to have calcifications bysubsequent histological examination(7,8). Clearly, many breast cancers containmicrocalcifications that are smaller than the limits of resolution of conventionalmammography.The recent development of microfocal spot x -ray tubes adapted for mammographic usepromises to allow for increased microcalcification detectability; laboratory and clinicalstudies with such equipment have shown it to produce sharper, more detailed images of thebreast(9'10). This study involves in vitro comparisons of microcalcification detectabilityusing both conventional mammography apparatus and a wide variety of microfocal spottechniques (different recording systems, degrees of magnification, exposure parameters), inorder to demonstrate the ability of the various techniques to portray the fine detailnecessary for early breast cancer detection.Materials and MethodsA total of 13 radiographic techniques were evaluated, using three different x --ray tubes,three different recording systems, and various degrees of magnification (Table 1). Breastmicrocalcifications were simulated by a graded series of aluminum oxide specks of knownsize (Radiation Measurements, Inc., Middleton, WI), embedded in whole human breastspecimens. Specks ranged from 0.15 mm to 0.91 mm in size, as measured by a calibrated 10Xocular lupe. Specks were arranged randomly using 4 -12 particles of each of eight sizes.They then were sealed in place between two pieces of transparent tape. A differenttransparent -tape strip of specks was used for each breast specimen. The number, location,and distribution of specks of each size were recorded both visually and radiographicallyfor each of the strips of specks, to provide a baseline for comparison with subsequentobservations made from the radiographs under study.It is important to carry out a study of breast calcification detectability using actualhuman breast tissue, since the elemental composition, x -ray scattering properties, andcomplexity of anatomic structure of the human breast is not approximated in anyexperimental animal or in breast phantoms. We used ten whole, fresh (unfixed) breastspecimens from adult female cadavers and four whole surgical mastectomy specimens for thispurpose. These specimens were radiographed under conditions of uniform compression similarin degree to those employed clinically; the average compressed thickness of our 14specimens was 5.2 cm. For each specimen, the strip of aluminum oxide specks was positionedin a plane perpendicular to the central ray, alternatively on top of the specimen at mid -breast level, and at the bottom of the specimen. Precise measurements were made of focus -film distance and speck -film distance (object -film distance) so that the degree of speckmagnification could be calculated for each image.* American Cancer Society Junior Faculty Clinical Fellow.

Small amounts of milk of calcium settling to the bottom of multiple tiny benign breast cysts produce the mammographic picture of clustered linear and curvilinear calcifications when imaged in lateral projection with a horizontal x-ray beam. These calcifications, although benign, may be confused with the microcalcifications of carcinoma. Milk of calcium is found much more frequently in small breast cysts than anywhere else in the body. It is not at all uncommon, occurring in more than 4% of women undergoing diagnostic mammography. Fortunately, the overall mammographic appearance of milk of calcium cysts is quite characteristic, permitting them to be a differentiated from malignant breast microcalcifications with a high level of confidence.

This study investigates the duplication of dental xeroradiographs using duplicating (copy) film, Polaroid photography, and Xerox photocopying. Quantitative studies of the image quality of duplicated images demonstrate similar image degradation with duplication film and Polaroid photography and gross degradation with a Xerox photocopier. Subjective diagnostic assessments by general dentists and dental specialists indicated that copies made with the use of duplication film or Polaroid photography were adequate for the reproduction of dental xeroradiographs, whereas Xerox paper copying was unacceptably poor. This study was supported in part by funds from Biomedical Research Support Grant No. 4-529075-24187-3, National Institutes of Health, United States Public Health Service, Bethesda, Md.

Magnification mammography is an adjunct to conventional mammographic technique. It produces fine-detail breast images containing additional anatomic information that may prove useful in refining mammographic diagnosis, especially in cases where conventional imaging demonstrates uncertain or equivocal findings.

Patients with cancer frequently develop pneumonitis for which no cause is documented ante mortem. Noninvasive diagnostic techniques, such as sputum induction, are generally inadequate, especially in myelosuppressed patients. To avoid pulmonary contamination with organisms colonizing the oronasopharynx and to obtain uncontaminated speciemens, 38 patients underwent bronchial brushing utilizing a transtracheal approach after sputum induction and transtracheal aspiration failed to establish the etiology. Patients with thrombocytopenia were brushed after platelet transfusion. Eleven patients were not clinically considered to be infected; seven proved to have pulmonary metastases, of which one case was diagnosed by this technique; and four patients in whom no diagnosis was obtained by brushing subsequently proved to have interstitial fibrosis (three cases) or a collapsed lobe (one case). Twenty-seven patients were clinically presumed to be infected. Ultimately, 17 of these 27 patients were proven to have pulmonary infection, and 14 of these 17 were etiologically documented by brushing. In ten of the 27 patients presumed to be infected, no etiology could be established by any method. Seven of these ten patients were receiving broad-spectrum antibiotic therapy at the time. Significant but nonfatal complications, including hemoptysis, pneumothorax, and cervical cellulitis, occurred in seven patients; however, this procedure is a relatively safe and useful method to include in the orderly evaluation of myelosuppressed cancer patients with suspected pulmonary infections.

To overcome the problem of moisture obscuring projected slides that are enclosed in glass, a low-heat oven can be used to warm the slides before use. The ovens are relatively inexpensive and can effectively remove most if not all moisture from within the slides.

Controlled in vitro studies of breast microcalcification detectability were done comparing a wide variety of standard and state-of-the-art mammography techniques (conventional and microfocal spot x-ray tubes, screen-film and xeroradiographic recording systems, contact and magnification techniques). Results confirmed previous observations that geometric unsharpness is the limiting factor in microcalcification detectability for most conventional mammography systems. Results also indicated superior microcalcification detection for: xeroradiographic over screen-film recording systems, positive-mode over negative-mode xeroradiography, microfocal spot contact over conventional contact techniques, and microfocal spot magnification over all contact techniques. No differences were found between a standard screen-film technique and a screen-film technique requiring about one-half the radiation exposure. On the other hand, although there was no differences between standard xeroradiography and a modest-added-filtration (reduced-dose) xeroradiographic technique, standard xeroradiography demonstrated superior microcalcification detection over a reduced-dose technique that used large amounts of added beam filtration. The clinical applicability of these findings is discussed.

To offer mammographic screening to asymptomatic women at low cost requires a different approach than is appropriate for solving the more complex problems presented by symptomatic patients. Since the goal of screening is to detect unsuspected abnormalities, not to characterize them fully, operational procedures can be streamlined to maximize patient throughput and achieve substantial cost savings. Such procedures will be successful only if applied to large numbers of patients, thereby permitting cost reduction by economies of large-scale operation. Computerization of record-keeping and of image interpretation is ideally suited for screening examinations and permits further cost savings. Experience with a prototype low-cost screening program has shown that with only 15 patients per day, operation is feasible at a charge of $50 per patient. The income lost from asymptomatic patients, who will pay lower fees compared with the traditional mammography fees they now pay, is more than offset by the income generated by additional problem-solving mammograms needed to fully characterize screening-detected abnormalities and by the increased use of needle localization procedures to guide biopsy.

Accurate preoperative diagnosis of spontaneous perirenal hematoma is often difficult, especially if the clinical presentation is atypical.Roentgenographic evaluation will demonstrate an enlarged, poorly functioning, or nonfunctioning kidney that may be compressed or displaced by a nonopacifying mass. Nephrotomography can often aid in locating the mass in the perinephric space, but usually renal arteriography is the definitive diagnostic procedure.Our case of perirenal hematoma due to renal infarction illustrates the features which distinguish the infarction secondary to sickle-cell trait from the much more common embolic type.*

The systematic mammographic evaluation of a breast mass involves independent assessments of its size, location, density, shape, clarity of margins, and interval change from prior examination. Additional fine-detail mammograms should be obtained to facilitate this analysis, especially when an equivocal interpretation is planned. Definitively benign masses (those localized to the skin, of fat density, or of mixed density) will not require more attention. Among the remaining water-density lesions, those that have an even slightly stellate appearance should be considered suspicious for malignancy; virtually all of them will undergo biopsy. Well-circumscribed masses should next be evaluated by aspiration or US examination to establish or exclude the diagnosis of simple benign cyst. Only solid and indeterminate lesions will require further evaluation, with the ultimate decision for biopsy versus mammographic follow-up depending on the probability of malignancy determined by the combination of mammographic and physical findings as well as pertinent data from the medical history.

Approximately 30-50% of primary breast cancers have mammognaphically detectable calcifications [1]. These calcifications may be the only radiographic finding that suggests malignancy. When such neoplasms metastasize to axillany lymph nodes, the nodes may appear dense but usually lack mammographically detectable calcification or other abnormalities. Reports of calcified metastatic neoplasm in axillary nodes draining a primary breast cancer are rare [2, 3]. We report three additional cases to emphasize that metastatic disease should figure prominently in the differential diagnosis of calcified axillary nodes when associated with ipsilateral breast microcalcifications.

New electronic thermographic instruments capable of routine clinical examination need to be evaluated for their potential as a diagnostic aid in dentistry. This study assessed thermal symmetry of the face and neck in 20 normal subjects with the use of frontal and lateral views, at 1.0 degree C and 0.5 degree C sensitivity, under controlled conditions. Electronic thermographic images were analyzed for thermal symmetry, by means of a grid matching technique, in 12 anatomic regions and the overall face. Results indicated that thermal symmetry for the entire face was high (70.2%). The 12 specific facial areas demonstrated varying levels of thermal symmetry. Regions of high symmetry on frontal projections included the anterior portion of the neck (82.0%), the TMJ (80.0%), the lower lip (78.6%), and the upper lip (77.3%). The temporal region (46.7%) was found to be of relatively low thermal symmetry. Regions of high symmetry on lateral projections included the nasal region (69.5%) and the inframandibular region (67.0%). The posterior neck region (44.2%) was found to be of relatively low thermal symmetry. In general, normal subjects demonstrated high levels of thermal symmetry over most regions of the face. This pilot investigation is an early step in the evaluation of electronic thermography for future use in dentistry.

Before clinical trials of intraoral xeroradiography are begun, we felt the need to evaluate the clinical acceptability of the thicker, more rigid xerographic cassettes. We simulated these cassettes by fastening rigid acrylic plates of appropriate thickness to conventional film packets and then conducted parallel evaluations of simulated cassettes and conventional film packets, using thirty volunteer patients. We found no difference in anatomic placement, operator acceptance, and patient acceptance between the “cassettes” and film packets. The increased thickness and rigidity of intraoral xerographic cassettes should not prove disadvantageous to in vivo intraoral xeroradiography.

Each of the three breast imaging procedures discussed in this paper already has or may eventually have the ability to provide clinically useful information that complements the detailed anatomic information currently available from X-ray mammography. None of these procedures is expected to replace mammography as the first-line imaging technique for the detection and diagnosis of benign and malignant breast lesions. Computed tomographic (CT) scanning utilizes ionizing radiation to produce high-contrast images in a cross-sectional display. A few special indications for the procedure already have been established, applying to a very small percentage of mammography patients. However, it is unliksely that the technique will find much more widespread use in the future. Transillumination and magnetic resonance imaging do not use ionizing radiation, and are as yet unproved methods for breast cancer diagnosis.

This study evaluated the radiation dose reduction, operator acceptance, and patient acceptance of two types of leaded thyroid shields designed for use during intraoral dental radiography. Exposure levels were measured with thermoluminescent dosimeters on three groups of 20 patients undergoing complete mouth (20-film) surveys. Skin entrance dose to the thyroid was 20 mR per complete mouth survey without a shield in place, 12 mR per complete mouth survey with the experimental shield in place, and 9 mR with the commercial shield. Patients and radiologic technologist were surveyed to determine patient comfort and operator acceptability. Patient and operator acceptability were higher for the experimental shield than for the commercial shield.

This study determined the perceived strengths and weaknesses of xeroradiography, D-speed film, and E-speed film for intraoral radiography. Results indicated that xeroradiography was preferred for the imaging of structures useful in periodontics and endodontics whereas film demonstrated a low level of image artifacts and was judged to be better for the imaging requirements of routine restorative dentistry. D-speed film was rated higher than E-speed film. These subjective assessments are similar to previously reported pilot studies but differ from previously published objective studies, which showed no significant difference between the three imaging techniques. Although there are substantial subjective differences between xeroradiography, D-speed film radiography, and E-speed film radiography, all the techniques provide more than the threshold level of necessary diagnostic information and all techniques portray adequate information for evaluation of common abnormalities encountered in the oral cavity.

Experience with 2500 patients over age 30 studied by physical examination, x-ray mammography, and sonography enabled definition of several specific clinical situations in which sonography adds meaningful diagnostic information not provided by either of the other examinations. These include: palpable breast masses for cyst-solid differentiation; nonpalpable mammographic masses for cyst-solid differentiation; and women with a symptomatic area in the breast that shows only uniformly dense fibro-glandular tissue on x-ray mammograms. For women with radiographically dense breasts who have no breast symptoms, abnormal physical findings, or mammographic lesions, sonography will identify many benign cysts and also some benign solid lesions, but at best only rarely (none of the 587 cases in this study) will it detect an otherwise occult breast cancer. Our data suggest that sonography should not be a substitute for physical examination and mammography in women over age 30, but rather that in three specific clinical situations it can be a valuable addition to the standard diagnostic evaluation.

Artifact-reduction techniques applied to intraoral xeroradiography have reduced the overall artifact level by 56.4% and the single-image retake rate from 17.4% to 11.3%. Nevertheless, the frequency of xeroradiography artifacts is greater than for intraoral film radiography, whether using manual processing (1.8% retake rate) or automatic processing (3.4% retake rate). Methods to identify and prevent xeroradiographic image artifacts are discussed in detail.

Direct radiographic magnification (1.5 ×) of the breast with a microfocus x-ray tube was compared with conventional contact mammography. Measurements of modulation transfer functions, Wiener spectra, scattered radiation, and dosimetry permitted quantitative comparisons of resolution, noise, contrast, and patient exposure. Images of surgical specimens of the breast, and the breasts of 125 patients, were qualitatively compared. Magnification images were superior (increased resolution, reduced noise) to conventional mammography images, at the expense of increased radiation dose. Clinical study revealed that the superior magnification image is useful in distinguishing malignant from benign breast disease, in selected cases.

Dental xeroradiography is a high-quality intraoral imaging system which provides a potentially convenient, rapid, low-dose alternative to conventional film radiography. In this study the sensitometric properties of dental xeroradiography were investigated via assessment of high- and low-contrast xeroradiographic processor settings, transmission versus reflection densitometry, reciprocity-law failure, and kVp (tube voltage) plate dependence. Findings of the study indicated that imaging at high-contrast processor settings results in greater dynamic range but less exposure latitude than imaging at low-contrast processor settings. Determination of characteristic curves demonstrated greater contrast in reflection mode than imaging by transillumination for all but the very densest of images (greater than 1.6 O.D.). There was also little difference in characteristic curves produced from 50 to 90 kVp, indicating that the xeroradiographic plate exhibits a relatively constant sensitivity over the tube voltages tested if exposure is expressed in roentgens. Finally, no substantial reciprocity-law failure was observed for dental xeroradiography over a clinically relevant range of exposure times.

Breast calcifications may be categorized as benign, probably benign, and suggestive of malignancy. The interpretation scheme presented here utilizes a systematic structured approach: identify characteristically benign calcifications, for which no further evaluation is needed; define as suggestive of malignancy those remaining calcifications that present as isolated parenchymal clusters of tiny calcific particles; and (optional) attempt to downgrade some of these suspicious calcifications into the "probably benign" category, so that they can be managed by periodic mammographic follow-up rather than biopsy. The clinical acceptability of this approach will vary with local conditions; success in implementing it will encourage increased use of mammography, and ultimately, improved breast health care.

An experimental intraoral dental xeroradiographic system was evaluated for its ability to image structures important in periodontal radiographic interpretation. On consenting dental patients, similar x-ray projections were made on (1) conventional film radiographs and (2) experimental dental xeroradiographs. The resultant images were compared visually. In all categories examined the information provided by xeroradiography was either equal to or greater than that provided by conventional film radiographs. Intraoral dental xeroradiography appears to be a highly accurate, low-radiation, rapid, and convenient alternative to conventional intraoral radiography.

Direct radiographic magnification (1.5×) of the breast, using a microfocal spot x-ray tube and either a xeroradiographic or screen-film recording system, produces images superior in quality (improved resolution, reduced noise) to conventional contact mammograms. Six hundred twenty-one patients had a single magnification mammogram in addition to conventional mammography; 216 subsequently underwent biopsy within one month of study. The additional magnification mammogram increased the diagnostic accuracy of the conventional examination in 40% of the pathologically proved cases, particularly among those for which conventional mammograms were interpreted as equivocal for malignancy. The superior image quality of magnification mammograms appears useful in distinguishing malignant from benign breast disease.

This prospective study of 1239 women compares the breast cancer detecting abilities of state-of-the-art mammography and transillumination. Mammography was found to be the superior technique, detecting 80 (96%) of the 83 pathologically proven cancers, while transillumination detected only 44 (53%). Among cancers having the best prognosis, transillumination was even less accurate relative to mammography, detecting only 43% of malignancies that had not yet spread to axillary lymph nodes and only 19% of the nonpalpable cancers and cancers smaller than 1 cm, whereas mammography detected over 90% in each of these categories. None of the three cancers missed by mammography were detected by transillumination. Clearly, transillumination is not an acceptable substitute for mammography in the detection and diagnosis of breast cancer. Therefore, the current commercial promotion of transillumination seems to be premature.

We have conducted a study to assess the effects of digitization and unsharp-mask filtering on the ability of observers to detect subtle microcalcifications in mammograms. Thirty-two conventional screen-film mammograms were selected from patient files by two experienced mammographers. Twelve of the mammograms contained a suspicious cluster of microcalcifications in patients who subsequently underwent biopsy. Twenty of the mammograms were normal cases which were initially interpreted as being free of clustered microcalcifications and did not demonstrate such on careful review. The mammograms were digitized with a high-quality Fuji image processing/simulation system. The system consists of two drum scanners with which an original radiograph can be digitized, processed by a minicomputer, and reconstituted on film. In this study, we employed a sampling aperture of 0.1 mm X 0.1 mm and a sampling distance of 0.1 mm. The density range from 0.2 to 2.75 was digitized to 1024 grey levels per pixel. The digitized images were printed on a single emulsion film with a display aperture having the same size as the sampling aperture. The system was carefully calibrated so that the density and contrast of a digitized image were closely matched to those of the original radiograph. Initially, we evaluated the effects of the weighting factor and the mask size of a unsharp-mask filter on the appearance of mammograms for various types of breasts. Subjective visual comparisons suggested that a mask size of 91 X 91 pixels (9.1 mm X 9.1 mm) enhances the visibility of microcalcifications without excessively increasing the high-frequency noise. Further, a density-dependent weighting factor that increases linearly from 1.5 to 3.0 in the density range of 0.2 to 2.5 enhances the contrast of microcalcifications without introducing many potentially confusing artifacts in the low-density areas. An unsharp-mask filter with these parameters was used to process the digitized mammograms. We conducted observer performance experiments to evaluate the detectability of micro-calcifications in three sets of mammograms: the original film images, unprocessed digitized images, and unsharp-masked images. Each set included the same 20 normal cases and 12 abnormal cases. A total of 5 board-certified radiologists and 4 senior radiology residents participated as observers. In the first experiment, the detectability of microcalcifications was measured for the original, unprocessed digitized, and unsharp-masked images. Each observer read all 96 films in one session with the cases arranged in a different random order. A maximum of 15 seconds was allowed to read each image. To facilitate receiver operating character-istic (ROC) analysis, each observer ranked his/her observation regarding the presence or absence of a cluster of 3 or more microcalcifications on a 5-point confidence rating scale (1=definitely no microcalcifications, 2=probably no microcalcifications; 3=microcalcifi-cations possibly present; 4=microcalcifications probably present; 5=microcalcifications definitely present). The observer identified the location of the suspected microcalci-fications when the confidence rating was 2 or greater. In the second experiment, we evaluated whether reading the unsharp-masked image and the unprocessed digitized image side by side for each case would reduce false-positive detection rates for microcalcifications and thus improve overall performance. The observer was again allowed a maximum of 15 seconds to read each pair of images and was instructed to use the unsharp-masked image for primary reading and the unprocessed digitized image for reference. The experimental setting and procedures were otherwise the same as those for the first experiment.

The radiographic distribution of pulmonary abnormalities in bronchopulmonary dysplasia (BPD) in all previously reported cases has been bilateral and generalized. The authors studied 11 premature infants who had BPD that was primarily unilateral. The striking feature in each of these patients was the occurrence of an episode of prolonged unilateral atelectasis or tension pneumathorax. Few, if any, radiographic manifestations of BPD developed. Results of a detailed analysis of oxygen exposure and respirator therapy during the periods of unequal lung ventilation further characterizes the protective effect of atelectasis and tension pneumothorax in the development of BPD.

Sonographic detectability of mammographically demonstrable breast calcifications depends primarily on the size of the calcific particles. Calcifications smaller than 2 mm in size are detected in fewer than 10% of cases, with equally low detection rates for benign and malignant particles. The inability of sonography to routinely identify malignant breast calcifications will severely restrict its use as a screening tool for cancer detection.© (1983) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Recent advances in technology have made radiographic magnification of the skeletonclinically feasible. A new electron gun micro -focal spot tube combined with new high -resolution recording systems were used to perform magnification radiography, which was thencompared with conventional contact radiography. Quantitative evaluation included measure-ments of speed, contrast, resolution, and noise. Qualitative evaluation included ananalysis of 215 clinical cases in which both techniques were used. The superior imagequality of direct radiographic magnification is confirmed and the clinical areas in whichit proved most helpful are defined.IntroductionThis discussion reviews the methodology, results, and implication of a preliminaryanalysis in which several direct magnification radiographic techniques are comparedquantitatively and qualitatively with several selected conventional radiographic techniquesfor skeletal applications. Additionally, an initial 12 months clinical experience withmagnification is assessed in order to define the areas in which magnification is useful.Methods and MeasurementsFour radiographic techniques are studied (Table 1), i.e., for thin parts, a conventionaland a comparison magnification technique, and similarly for thick parts, a conventionaland a comparison magnification technique. The two conventional techniques employ standardradiographic procedures and equipment widely used for skeletal radiography. The two magni-fication techniques employ 3X direct magnification using a nominal 0.1 mm focal spot tube(RSI MFT1, Radiologic Sciences, Inc.) and relatively high -resolution recording systems.The typical exposure conditions for these four techniques are given in Table 1. Thin bodyparts are exposed at 50 -60 kVp and thick body parts at 65 -75 kVp. The conventional tech-niques use high mA, short exposure times, and standard distances. A Bucky grid is usedonly with the conventional technique for thick parts. The magnification techniques use themaximum setting of 3 mA and require relatively long exposure times at short distances.Table 1. Four Radiographic Techniques ExaminedThin Parts Thick PartsConventional Magnification Conventional MagnificationRP Cardboard1.2 mm F.S.1.03X Mag.

Excerpt To the editor: The thoracic outlet syndrome is characterized by symptoms of compression of the brachial plexus and subclavian artery and vein, usually between the clavicle and first rib. Re...

Mammographic demonstration of tiny clustered calcifications often is the first and only means of detecting breast cancer at a small, highly curable stage [1]. As a result, radiologists frequently recommend biopsy when such calcifications are identified. A notable exception to this practice occurs when apparently intramammary calcifications are Icalized to the skin overlying the breast, because this nonparenchymal finding is never associated with underlying malignancy [2]. The purpose of this case report is to describe another type of extramammary microcalcification, situated within the pectoral muscles, in order to alert radiologists to the need for localizing deep as well as superficial calcifications to parenchymal location before raising the suspicion of malignancy.

We attempted to use hand-held, high-resolution breast sonography to localize for biopsy 11 solid, nonpalpable lesions detected by mammography. Using sonography, we identified and localized only one of four lesions presenting as poorly defined masses and only one of seven lesions presenting as clusters of tiny calcifications. This 18% rate of success is too low to justify the use of sonography for all patients undergoing needle localization. Mammography remains the procedure of choice for localizing solid, nonpalpable breast masses and clustered calcifications.

Laboratory comparisons of the resolution, noise, and contrast of five mammography screen-film systems (single screen, single-emulsion film) were made both qualitatively and quantitatively. Subjective single-blind estimations of resolution, noise, and contrast were also made directly from the mammograms of 100 consecutive patients radiographed with each of the screen-film systems. Laboratory and clinical evaluations showed strikingly similar results: improved contrast, minimally reduced resolution, and varying degrees of increased noise for the faster recording systems. Similarities between the results of laboratory and clinical studies should help to establish the clinical relevance of the laboratory analyses, and recognition of the relative precision of the clinical evaluations should allow for their use in place of laboratory studies when sophisticated physics support is not available.

Inability to accurately diagnose infection in granulocytopenic patients is a major cause for morbidity and mortality, and prompted this study of 344 infections (pharyngitis, skin infection, pneumonia, anorectal infection, and urinary tract infection) in a select group of cancer patients. Strikingly similar alterations in clinical presentation were found for all infections that developed in profoundly granulocytopenic patients. Physical findings of exudate, fluctuation, ulceration or fissure, local heat, swelling, and regional adenopathy were all less prevalent in the granulocytopenic patient, while fever was much more common. Only erythema and local pain or tenderness were present in practically all patients regardless of site of infection or level of granulocyte count. A better understanding of how granulocytopenia affects the presentation of infection should lead to earlier and more accurate diagnosis and potentially to more successful therapy.

HEMATOLOGIC neoplasms and their therapy frequently result in seriously altered host defenses, thus enhancing susceptibility to infection with opportunistic organisms. Torulopsis glabrata is a yeast-like organism commensal in the vagina of healthy women. 1 Human infection is rare, but may occur in patients with altered host defense mechanisms. The organism has been reported to cause esophagitis, 2 endometritis, 1 cystitis, 3 pyelonephritis, 3 wound infection, 3 and fungemia, 1,3,4 nd has been isolated from sputum and lung tissue at autopsy. 2 Torulopsis glabrata has been isolated at the Baltimore Cancer Research Center on surveillance cultures, 5 and occasionally from lung tissue at autopsy, but antemortem clinical pneumonitis has not previously been recognized. This organism was implicated as the cause of a fatal pneumonia in a severely myelosuppressed patient. 1 The cultures were obtained five hours postmortem and were not taken directly from the area of involvement; nevertheless, histological examination of

Pneumonia is a quite frequent and often fatal complication in patients with acute leukemia. During a 19-month period 52 episodes of pneumonia were found among 68 leukemia patients. Except ...

Three of 15 cancer patients with suspected intrathoracic tumor recurrence were found on biopsy to have only benign mass lesions. These cases emphasize that medical work-up, short of biopsy, is often inadequate in the evaluation of intrathoracic masses, and that a history of neoplasm is not sufficient cause to abandon tissue diagnosis before proceeding to therapy.