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Purpose: The aim of this study is to examine the reproducibility of anti-1-amino-3-[(18)F]fluorocyclobutane-1-carboxylic acid (anti-3-[(18)F]FACBC) quantitative measurements in key background structures and untreated malignant lesions., Procedures: Retrospective review of 14 patients who underwent follow-up anti-3-[(18)F]FACBC positron emission tomography-X-ray computed tomography (PET-CT) for prostate carcinoma recurrence. Standard uptake values (SUV) were measured in both original and follow-up scans in key background structures and untreated malignant lesions. Absolute and percent mean difference in SUV between scans and interclass correlation coefficients (ICC) were also computed., Results: Mean (±SD, range) scan interval was 17.4 months (±7.1, 4-29). %Mean difference in SUVmean was <20 % in background structures with low absolute differences. ICCs were >0.6 except for early-phase blood pool (ICC = 0.4). SUVmax in malignant lesions without interim therapy increased or remained stable over time., Conclusions: Despite variable time interval between scans, FACBC PET-CT demonstrates acceptable reproducibility in key background structures. Untreated malignant lesions showed stable or increased uptake over time. A formal test-retest study is planned.

Purpose: Anti-1-amino-2-[(18)F]fluorocyclopentane-1-carboxylic acid (anti-2-[(18)F]FACPC) is an unnatural alicyclic amino acid radiotracer with high uptake in the DU-145 prostate cancer cell line in vitro. Our goal was to determine if anti-2-[(18)F]FACPC is useful in the detection of prostate carcinoma., Procedures: Five patients with elevated PSA (1.1-20.5 ng/mL) after curative therapy for prostate carcinoma underwent 60 min dynamic positron emission tomography (PET) of the pelvis after IV injection of 193-340 MBq of anti-2-[(18)F]FACPC. Uptake was compared against PET scans in the same patients with the leucine analog, anti-1-amino-3-[(18)F]fluorocyclobutane-1-carboxylic acid (anti-[(18)F]FACBC), at similar time points and validated via pathology, clinical, and imaging follow-up., Results: At 5 min, average (±SD) SUVmax of malignant lesions is 4.1(±1.3) for anti-2-[(18)F] FACPC and 4.3(±1.1) for anti-[(18)F]FACBC. Yet, blood pool activity at 5 min is significantly higher for anti-2-[(18)F]FACPC with average (±SD) lesion/blood pool SUVmax/SUVmean ratio of 1.4 (±0.5) vs. 3.0 (±0.9) for anti-[(18)F]FACBC. At 20 min, average (±SD) SUVmax of malignant lesions is 2.6 (±1.0) for anti-2-[(18)F]FACPC and 3.4 (±0.8) for anti-[(18)F]FACBC. Yet, bladder activity at 20 min is significantly more intense for anti-2-[(18)F] FACPC with average (±SD) lesion/bladder SUVmax/SUVmean ratio of 0.3 (±0.8) vs. 2.3 (±1.4) for anti-[(18)F]FACBC., Conclusions: While prostate bed lesions are visible on early imaging with anti-2-[(18)F]FACPC, there is high blood pool activity obscuring nodes. As blood pool fades, nodal uptake decreases and high bladder activity then obscures pelvic structures. Compared with anti-[(18)F]FACBC, imaging characteristics for anti-2-[(18)F]FACPC are unfavorable for pelvic recurrent prostate carcinoma detection.

Objective: To compare the diagnostic accuracy of Rb-82 myocardial perfusion three-dimensional (3D) PET with and without prompt-gamma compensation (PGC)., Methods and Results: Retrospective, single center study of 76 patients who had rest and adenosine stress Rb-82 myocardial perfusion 3D PET. All studies were acquired using a Siemens Biograph-40 PET/CT scanner and were reconstructed with and without PGC. Fifty-seven patients (mean age 63 +/- 11 years, 26 men) had coronary angiography within 40 days of Rb-82 imaging. Nineteen patients (mean age 43 +/- 7 years, 10 men) had low likelihood of coronary artery disease (CAD). All PET images were scored by consensus of two blinded readers on a standard 5-point scale using a 17-segment left ventricular model. A normal PET test was defined as a summed stress score of less than four. Obstructive CAD at coronary angiography was used as the gold-standard and was defined as luminal stenoses > or =50% in one or more major coronary arteries. The prevalence of obstructive disease at coronary angiography was 68% (39/57). The mean summed stress score was 12 +/- 12 for PGC images and was 18 +/- 14 for non-PGC images. Sensitivity and specificity for obstructive CAD were 90% (95% CI 88-99) and 72% (95% CI 52-93) for PGC images and 95% (95% CI 88-100) and 22% (95% CI 3-41) for non-PGC images., Conclusion: PGC in Rb-82 3D PET improves the specificity for obstructive CAD at coronary angiography with no significant loss in sensitivity.

Purpose: Assessment of renal masses with conventional imaging may be challenging. Anti-1-amino-3-[(18)F]fluorocyclobutane-1-carboxylic acid (anti-[18F]FACBC) is a synthetic L: -leucine analog with relatively little renal excretion. The present study examines anti-[(18)F]FACBC positron emission tomography uptake in patients with renal masses., Procedures: Six patients with seven renal lesions were imaged dynamically for 2 h after injection of 10-10.9 mCi (370-403 MBq) anti-[(18)F]FACBC. Lesions were evaluated qualitatively and quantitatively and correlated with histology., Results: Four clear cell and one Rosai-Dorfman lesion were hypo/isointense to normal cortex; two papillary lesions in the same patient were hyperintense. Mean SUV(max) +/- SD at 30 min was 2.8 +/- 0.24 for clear cell carcinomas and 4.5 +/- 1.7 for papillary cell lesions. Mean SUV(max)/SUV(mean) ratios +/- SD of lesion to normal cortex at 30 min was 1.15 +/- 0.19 for the clear cell carcinomas and 2.3 +/- 0.84 for papillary cell., Conclusions: In this small patient sample, relative amino acid transport compared with renal cortex is elevated in renal papillary cell carcinoma but not in clear cell carcinoma.

Purpose: This study was undertaken to determine if artifacts from misalignment of cardiac emission to transmission data is present in adenosine stress studies and if the artifact could be reproduced by intentional misalignment in normal exams., Procedures: Seventy consecutive 82Rb myocardial perfusion studies were reviewed. Utilizing a quality control program, misalignment was assessed. The study was reprocessed after manual realignment to determine if the defect extent changed. Emission and transmission acquisitions in six normal studies also were intentionally misaligned., Results: Twenty of 69 rest studies (29.0%) and 17 of 69 (24.6%) stress studies demonstrated misalignment. In four patients with stress misalignment, there was a significant change in clinical interpretation. Upon intentionally misaligning six normal studies, a lateral wall defect was reproduced., Conclusions: Emission-transmission misalignment occurs in 29.0% and 24.6% of 82Rb rest and adenosine stress studies, respectively. While there is a positive correlation of artifactual defects with misalignment, the presence and size of artifacts is variable and unpredictable at seemingly lesser degrees of misalignment.

Background: Transient ischemic dilation (TID) has been established as an important independent marker of severe and extensive coronary artery disease (CAD) in myocardial perfusion imaging (MPI). The accuracy of the TID index is dependent on a well-determined threshold (normal limits) between normal and abnormal values for each study protocol. To date, the effects of neither gender nor attenuation correction (AC) on TID normal limits have been established. Thus, the objectives of this study were to determine if AC processing changes the normal value of the TID index and if there were gender-related differences in the TID index of normal patients who had undergone rest/exercise-stress technetium-99m sestamibi MPI., Methods and Results: Seventy-five patients (33 women, 42 men; mean age, 57.7 +/- 11.7 y and 55.9 +/- 10.0 y, respectively) with less than a 5% likelihood of CAD, who had undergone low-dose rest/high-dose exercise-stress Tc-99m sestamibi MPI, were studied. All studies were acquired using simultaneous emission/transmission scans and were corrected for attenuation, scatter, and resolution effects using the ExSPECT II method. Both the AC and non-AC studies were analyzed using the Emory Cardiac Toolbox (ECTb; Syntermed, Inc, Atlanta, Ga) quantitative software. The TID index was calculated automatically as the ratio of stress mean left ventricular volumes to rest mean left ventricular volumes by ECTb. Patients were grouped by gender and the TID indices from AC and non-AC studies were compared. Linear regressions of the TID index and body mass index were analyzed to exclude differences in body size between male and female patients as a confounding factor in gender-related differences in TID. The TID index upper normal limits were calculated as the mean value plus 2 standard deviations (SDs). AC processing did not change the TID index significantly whether the genders were combined or separated (AC TID = 0.97 +/- 0.14 vs non-AC TID = 0.98 +/- 0.12 for all patients). Female patients showed higher mean TID indices than male patients in both AC (1.01 +/- 0.15 vs 0.95 +/- 0.12) and non-AC studies (1.00 +/- 0.15 vs. 0.97 +/- 0.10), but this difference was statistically significant only in AC studies (p = .03). TID indices remained constant across the range of body mass index studied. The TID index upper normal limit was 1.31 for female and 1.18 for male patients., Conclusion: TID normal values for rest/exercise-stress Tc-99m sestamibi MPI are gender-dependent and not affected by AC processing. Thus, diagnosticians should take into account these gender-related differences, as compared with the traditional value generated from mostly male populations, to ensure both men and women have the same overall accuracy of using the TID index in the diagnosis and prognosis of CAD.

Background: A gender-independent stress normal database and criteria for abnormality for attenuation-corrected rest-stress technetium 99m sestamibi same-day myocardial perfusion imaging were developed by evaluation of 112 patients, validated against an obese population of 95 patients from four different clinical sites, and compared with conventional gender-matched database quantification of non-attenuation-corrected studies., Methods and Results: These 95 validation patients (63 men) were used for prospective quantitative evaluation (mean weight, 213 +/- 57 lb; mean body mass index, 32 +/- 9 kg/m(2)). This group included 21 patients (12 men) with a lower than 5% likelihood of coronary artery disease (mean weight, 226 +/- 72 lb; mean body mass index, 34 +/- 13 kg/m(2)) and 74 who underwent cardiac catheterization within 2 months (35 with normal coronaries or coronary lesions <70%). These studies were processed twice, once by use of conventional reconstruction and gender-specific database quantification and a second time by use of attenuation correction and a single gender-independent attenuation-corrected normal database. The attenuation-corrected normal database and criteria for abnormality were developed by evaluation of 48 and 78 patients, respectively. No statistically significant differences were found when comparing attenuation-corrected perfusion distributions of normal men and women, whereas significant differences were found in the same uncorrected studies. Compared with quantitative analysis of the uncorrected studies, quantitative analysis of the attenuation-corrected studies by use of a gender-independent normal database demonstrated a significant improvement in normalcy rate (90% vs 52%, P =.006) and specificity (57% vs 29%, P =.015) in this obese population at no significant loss in sensitivity (90% vs 97%, P = not significant)., Conclusion: Attenuation-corrected studies can be quantified with a single gender-independent normal database and a single criterion for abnormality without loss of sensitivity and with significantly better specificity and normalcy rate.

No study has reported an association between gastroesophageal reflux disease (GERD) or its therapies and gallbladder function. We compared pre- and postoperative gallbladder function in patients undergoing fundoplication to determine the following: (1) whether patients with chronic GERD have preexisting gallbladder motor dysfunction; (2) whether medical or surgical therapy alters gallbladder function; and (3) whether division of the hepatic branch of the anterior vagus nerve is detrimental to gallbladder motility. Nineteen patients with documented GERD consented to a preoperative cholecystokinin-stimulated technetium hepatobiliary (CCK-HIDA) scan to quantify the gallbladder ejection fraction (GBEF). All patients underwent laparoscopic Nissen fundoplication. One month after fundoplication, 12 patients completed a repeat CCK-HIDA scan for determination of GBEF, with comparison to the preoperative GBEF. Among patients with preoperative GERD, 11 (58%) of 19 met the scintigraphic criteria for gallbladder dysfunction (GBEF <35%), which is a ratio comparable to that in patients undergoing a CCK-HIDA scan for presumed biliary dyskinesia during the same time period (31 [60%] of 53; P = NS, chi-square test) and exceeds the rate of abnormal GBEF reported in healthy volunteers (3%). Six of seven patients with a low preoperative GBEF who underwent repeat evaluation postoperatively had normalization of the GBEF (P < 0.05, paired t-test). In the 12 patients who underwent postoperative CCK-HIDA scanning, there was no association between preservation or division of the hepatic branch of the anterior vagus nerve and postoperative gallbladder dysfunction (P = NS, chi-square test). Unexpectedly, 58% of patients with GERD demonstrated gallbladder motor dysfunction prior to fundoplication, with improvement to normal occurring in most of those studied postoperatively. These data support controlled trials to determine the effect of chronic GERD and antisecretory therapy on gallbladder and global gastrointestinal smooth muscle function. Preservation of the hepatic branch of the anterior vagus nerve during fundoplication offered no clear benefit with regard to early postoperative gallbladder function.