Quantifying midbrain serotonin transporter in depression: a preliminary study of diagnosis and naturalistic treatment outcome.

INTRODUCTION: Serotonin may play an important role in the pathology of major depressive disorder (MDD). However, the relationship between serotonin transporter (SERT) availability and the medical outcome of antidepressant treatment is uncertain. METHODS: In this naturalistic study, SERT availability (expressed as the specific uptake ratio, SUR) in the midbrain of 17 drug-free patients with MDD and 17 controls matched for age and gender was measured using SPECT with [(123)I]ADAM. The severity of MDD was measured by the Hamilton Depression Rating Scale before, and after 6 weeks of non-standardized antidepressant treatment. RESULTS: A total of 12 patients completed the study. The SUR of the patients with MDD was significantly lower than that of the healthy controls. The SUR of SERT was not found to have a linear relationship with the treatment outcome; however, supplemental analysis found a curvilinear relationship between treatment outcome and the SUR of SERT. DISCUSSION: The findings indicate that the SUR of SERT is lower in patients with MDD; however it did not predict treatment outcome in a linear fashion. Studies with larger sample sizes are required.

The use of dual-phase 18F-FDG PET in characterizing thyroid incidentalomas.

AIM: To examine the usefulness of dual-phase 2-[18F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography (PET) for the evaluation of thyroid incidentalomas. MATERIALS AND METHODS: In this retrospective study, cases with focal thyroid lesions seen incidentally at FDG PET in which the histopathological diagnosis was available and in which dual-phase FDG PET imaging was performed at 1 and 2 h after FDG injection were reviewed. In the included cases, the 1 and 2 h maximal standard uptake value (1-hour maximal SUV and 2-hour maximal SUV, respectively) and retention index (RI) were calculated, and the differences between benign and malignant thyroid incidentalomas were analysed. Receiver operating characteristic (ROC) analysis was performed to evaluate the ability of 1-hour maximal SUV, 2-hour maximal SUV, and RI to discriminate benign from malignant lesions. RESULTS: A total of 39 patients (25 females, 14 males) with 45 lesions (17 malignant, 28 benign) were included. In malignant thyroid incidentalomas, the average 1-hour maximal SUV, 2-hour maximal SUV, and RI were 5.20, 5.72, and 7.67%, respectively, and in benign thyroid incidentalomas the values were 4.67, 4.97, and 7.38%, respectively. There were no significant differences in 1-hour maximal SUV, 2-hour maximal SUV, and RI between benign and malignant lesions. The area under the ROC curve did not differ from 0.5. CONCLUSION: Dual-phase FDG PET is not useful for differentiating benign from malignant thyroid incidentalomas.

Discriminating glucose tolerance status by regions of interest of dual-energy X-ray absorptiometry. Clinical implications of body fat distribution.

OBJECTIVE: To determine whether measuring body fat distribution by dual-energy X-ray absorptiometry (DEXA) can be used to discriminate glucose tolerance status. RESEARCH DESIGN AND METHODS: Using a 75-g oral glucose tolerance test, a total of 1,015 Chinese subjects (559 men and 456 women) were categorized as having normal glucose tolerance (NGT), impaired glucose tolerance (IGT), or diabetes. Blood pressure and lipid profiles of these subjects were measured. Waist-to-hip ratio (WHR) and DEXA were used to evaluate the varying patterns of body fat distribution among the groups. RESULTS: Body fat distribution, as reflected by WHR and the centrality index, showed significant partial correlation coefficients with glycosylated hemoglobin, blood pressure, and lipid profiles in all subjects. After adjusting for age and BMI, there were significant differences among the three glycemic groups for all the cardiovascular risk factors except for total cholesterol level. The diabetic group had a significantly higher WHR and centrality index, but lower femoral fat percentage than the NGT and IGT groups. The diabetic group also showed higher abdominal fat percentage than the NGT group. Moreover, the IGT group had a higher centrality index than the NGT group. However, no significant differences were found in the percentage of lean tissue mass among the three groups. Using multiple stepwise logistic regression models, the centrality index remained a significant factor for discriminating different glucose tolerance status independent of the percentage total body fat. CONCLUSIONS: Central obesity has shown significant correlation with cardiovascular risk factors among the three different glycemic groups. Centrality index measured by DEXA appears to be the better predictor of glucose intolerance, compared with WHR, abdominal fat, and general obesity (reflected by percentage total body fat or BMI) in a large cohort of the Chinese population.

The correlation between mid-brain serotonin transporter availability and intelligence quotient in healthy volunteers.

PURPOSE: This study was performed to investigate the association between the mid-brain serotonin transporter (SERT) availability and intelligence quotient (IQ). METHODS: One hundred and thirteen healthy participants, including 52 male and 61 female subjects, were recruited. We used SPECT with [(123)I]ADAM images to determine the SERT availability in the mid-brain, and measured the subjects' IQ using the WAIS-R. RESULTS: We found a significant positive correlation between the mid-brain SERT availability and the IQ of the participants. Even when controlling for age and sex, the significant association still existed. CONCLUSION: This result implied that the higher the SERT binding in the mid-brain, the better the IQ in healthy participants.

Technetium-99m(V)-DMSA and gallium-67 in the assessment of bone and joint infection.

UNLABELLED: The aim of our study was to investigate the diagnostic value of scans with 99mTc(V)-dimercaptosuccinic acid (DMSA) to localize bone and joint infection compared with scans using 67Ga. METHODS: Thirty-six patients referred for investigation of bone and joint infection were studied. In all patients, a bone scan was obtained initially. Subsequently, comparative scans with 99mTc(V)-DMSA and 67Ga were performed 1 wk apart. Microbiological findings, pathologic findings and/or clinical follow-up (until symptoms disappeared) were considered to be proof of the presence of bone and joint infection. RESULTS: Technetium-99m (V)-DMSA showed greater sensitivity and accuracy than 67Ga in the assessment of bone and joint infection, although the difference was not statistically significant. CONCLUSION: In comparison with a 67Ga scan, a 99mTc(V)-DMSA scan, in combination with a bone scan, is a reliable way to diagnose bone and joint infection. Both tracers were useful in the diagnosis of bone and joint infection.

Technetium-99m-HMPAO brain SPECT in neonates with hypoglycemic encephalopathy.

Regional brain injury in three neonates with hypoglycemic encephalopathy are presented using serial 99mTc-hexamethyl propyleneamine oxime (HMPAO) SPECT and, for comparison, MRI. During the acute stage, both 99mTc-HMPAO SPECT and MRI reveal abnormalities in the posterior cerebrum. Technetium-99m-HMPAO SPECT reveals further areas of insult, for example the frontal lobes. The degree of hypoperfusion correlates with the clinical severity of hypoglycemia during the neonatal period and subsequent neurological sequelae. Follow-up with HMPAO SPECT several months after insult demonstrates persistent hypoperfusion in some areas, mainly in the occipital and posterior parietal regions. MRI can depict morphological changes with superior resolution. Because morphological change generally follows slowly after functional change, MRI is less sensitive than HMPAO SPECT in detecting and predicting the extent of hypoglycemic cerebral injury during the acute phase. HMPAO SPECT during the acute stage is a valuable tool for evaluating the extent and severity of brain injury in neonates with hypoglycemic encephalopathy.

Evaluation and validation of ureteric jet index by glomerular filtration rate.

RATIONALE AND OBJECTIVES: Ureteric jet index (UJI), a newly developed technique derived from color Doppler ultrasonography, may hold promise in evaluating renal function because of its ability to evaluate individual renal function and the use of nonionizing radiation. To assess the usefulness of UJI, the authors in this study analyzed the relation between UJI and the glomerular filtration rate (GFR). METHODS: Fifteen adult patients with a wide range of renal function were included in this study. Subjects were well hydrated before color Doppler ultrasonography examinations. The UJI formula was: Vmean (average jet velocity) x D (jet duration) x F (jet frequency). GFR was calculated by the radionuclide method. Correlations between UJI, serum creatinine, and GFR were analyzed. RESULTS: Ureteric jet index had only a fair correlation with GFR. The coefficient of correlation value was 0.61, and the standard error of estimate of GFR was 17.9 mL/min. CONCLUSIONS: With the measurement of UJI, color Doppler ultrasound can provide both structural images and individual renal function information. It could substitute for a renal scan in determining individual renal function when a radionuclide examination is unavailable. Even if a renal scan were available, UJI can play a valuable role in the ultrasound examination of patients with suspected impaired renal function, providing further assessment of individual renal function.

Melanoma of oronasal mucosa. Population-based analysis of occurrence and mortality.

OBJECTIVES: To document the incidence and trends of oronasal melanoma with time, place, and person and to provide population-based estimates of survival and prognostic factors. DESIGN: Descriptive analysis of 9 population-based cancer registries in the United States for the years 1973 to 1991. SUBJECTS: All patients with primary melanoma of the oronasal mucosa who resided in the registry areas, which included approximately 10% of the US population. INTERVENTIONS: None. RESULTS: The incidence of oronasal melanoma was 0.041/10(5) per year. There were no significant race or gender differences in incidence. Melanomas of the nasal cavity were more common in the northern registry areas, and increased in incidence during the 19-year study period. Oral melanomas were less common in the North, and did not change significantly in incidence. The median survival with oronasal melanoma was 2 years, and the 5-year survival (+/- SE) was 25% (+/- 4%). Advanced age and stage were adverse prognostic features, but no significant differences in the prognosis were noted by anatomic subsite. CONCLUSIONS: We have documented the incidence and prognosis of oronasal melanoma based on a large population-based sample. The prognosis is poor. The epidemiologic features differ substantially from those of cutaneous melanoma.

Measurement of organ volume by single photon emission computed tomography.

The aim of this study was to develop a new algorithm for volume determination by single photon emission computed tomography (SPECT). Different algorithms were evaluated through phantom studies. The results show that the algorithm combining moment-preserving bilevel thresholding and best-fit Laplacian second derivative edge detection can provide the most accurate measurement of volume. Besides, this method can be utilized in different SPECT systems with no need for further phantom studies. In patient studies, the results of liver volume calculation have indicated that this is a useful technique in clinical medicine.

The value of 67Ga-citrate scanning in psoas abscess.

Psoas abscess is a serious health problem which presents with non-specific symptoms and signs. To reduce morbidity and mortality, it is important to diagnose the presence and extent of a psoas abscess accurately using imaging studies. Because the 67Ga scan may facilitate the early diagnosis of insidious infection and assist CT-guided percutaneous drainage of the abscess, we examined the value of 67Ga scans in 18 patients with psoas abscess. The imaging results of 67Ga scans (18 patients), computed tomography (CT) (16 patients) and bone scans (13 patients) were analyzed. In this series, concomitant infections were very common (94%) in patients with psoas abscess. For detecting psoas abscess, the sensitivity of 67Ga scanning (92%) and CT (91%) was similar. However, 67Ga scanning is superior to CT in demonstrating concomitant infectious foci at other sites. Bone scanning is a sensitive tool for depicting osteomyelitis, which was common in this series of patients. We also found that increased vascularity in the psoas area was demonstrated by three-phase bone scanning in 60% of patients.

Evolution of differential renal function after acute pyelonephritis.

(99m)Tc dimercaptosuccinic acid (DMSA) renal scans can provide accurate diagnosis of acute pyelonephritis, its sequelae (renal scars) and differential renal function (DRF). The purposes of this retrospective study were (1) to assess the relationship between DRF obtained during acute pyelonephritis and at follow-up, and (2) to elucidate the value of initial DRF in predicting subsequent renal scars. A total of 47 children were enrolled. All had both unilateral acute pyelonephritis diagnosed by initial DMSA renal scans, and follow-up DMSA renal scans. We found the correlation between initial and follow-up DRF poor (adjusted R2 = 0.396). Whether or not renal scars developed determined the follow-up DRF. Vesicoureteral reflux was significantly more common in children who developed renal scars. In addition, the higher the grade of vesicoureteral reflux, the lower the follow-up DRF and the improvement in DRF. When using a DRF of 46% as the cut-off value to predict subsequent renal scars, the sensitivity and specificity were 47.8% and 83.3%, respectively. Owing to the low sensitivity, initial DRF is not suitable for predicting the occurrence of renal scars.

Clinical significance and outcome of one or two rib lesions on bone scans in breast cancer patients without known metastases.

The presence of one or two rib lesions on bone scans of post-treatment breast cancer patients without known metastases often makes clinical decision making problematic. The aim of this study was to identify skeletal metastasis predictors that might help the management of these patients. We recruited post-treatment breast cancer patients without overt metastases whose bone scans showed (1) one or two rib hot spots, or (2) one rib lesion and a concurrent bone abnormality. Their clinical and serial scintigraphic data were collected, reviewed and evaluated for correlations. After their first abnormal bone scans, 23 patients (11 of the 77 patients initially with one rib lesion (incidence, 14.3%), three of the 27 patients with two rib lesions (incidence, 11.1%), and nine of the 11 patients with one rib lesion plus a concurrent bone abnormality (incidence, 81.8%)) developed multiple bone metastases within 2 years of the initial rib lesions in all but one case. Univariate analyses revealed that a concurrent bone lesion other than the rib, direct tumour invasion to the chest wall or skin, and 10 or more lymph nodes involved were associated with increased risks of bone metastases whereas longer persistence of the rib lesions was associated with a lower risk. Multivariate proportional hazard analyses indicated that patients with a concurrent bone lesion other than the rib (relative risk (RR)=39.65; 95% confidence interval (CI)=8.13-193.28), 10 or more lymph nodes involved (RR=13.49; 95% CI=2.09-86.91), and no radiotherapy (RR=7.59; 95% CI=2.11-27.39) were more likely to have bone metastases, while those with longer persistence of the rib lesions (RR=0.92; 95% CI=0.84-0.98) and longer time interval between surgery and the rib lesion detection (RR=0.96; 95% CI=0.94-0.99) were less likely. We have identified clinical features applicable to risk stratification. High incidence of bone metastases was noted in patients with one rib lesion and a concurrent bone abnormality. Regular follow-up for 2 years after detection of rib lesions is recommended, especially for those with risk factors.

Synchronous pyomyositis and septic hip arthritis.

The authors report a rare concomitant pyogenic infection of the iliopsoas, iliacus and external obturator muscles and of the hip joint in a 68-year-old woman. Because the patient showed the classic symptomatic triad of limping, hip pain and fever, in addition to positive hip arthrocentesis, the diagnosis of septic hip arthritis was routine, but the simultaneous pyomyositis was almost overlooked. Unusual localised heat and swelling on the front of the proximal thigh prompted a CT scan that identified remarkable muscle abscesses in addition to the septic arthritis. Surgical debridement and antibiotics resolved the infection relatively rapidly without sequelae. We noted that reaching a definitive diagnosis of such a concomitant infection requires a suspicion of the presence of pyomyositis, which can be definitively determined using advanced imaging studies.

Tc-99m sestamibi scanning in the preoperative localization of mediastinal parathyroid adenomas.

We report on two patients with mediastinal parathyroid adenomas who underwent preoperative Tc-99m sestamibi scintigraphy. Excellent physical characteristics of technetium and slow washout of Tc-99m sestamibi made possible clear delineation of mediastinal parathyroid adenomas by Tc-99m sestamibi imaging.

Detection of pelvic deep vein thrombosis by subcutaneous radionuclide venography utilizing an acupuncture point.

The authors present a case of thrombosis involving the right common iliac vein evaluated with subcutaneous radionuclide venography (SCRNV) after injection at acupuncture points. SCRNV demonstrated interruption of venous flow to the right common femoral vein and right iliac vein with prominent collateral venous drainage into the contralateral deep veins. This technique, which is technically simple and relatively operator-independent, has the potential to become a screen or follow-up test for deep vein thrombosis.

Heroin-induced rhabdomyolysis as a cause of reflex sympathetic dystrophy.

Reflex sympathetic dystrophy is an excessive or abnormal response of the sympathetic nervous system in an extremity to an injury or other condition. The authors describe a 37-year-old man who experienced constant pain and vasomotor instability in both feet after nontraumatic rhabdomyolysis secondary to smoking heroin. Three-phase bone scintigraphy was performed and revealed significantly increased blood-flow, blood-pool, and delayed-phase radioactivity. The follow-up three-phase bone scinitigram showed less radiotracer uptake that was consistent with a good response to calcitonin therapy. Heroin-induced rhabdomyolysis should be added to the list of precipitating conditions that can induce this syndrome.

Pyomyositis--with special reference to the comparison between extra- and intrapelvic muscle abscess.

Fifteen patients, nine males and six females, diagnosed with pyomyositis from 1988 to 1994, and followed for an average of 69.8 months, were reviewed. Excluding two children, the average age was 56.6 years. Eleven adults (73.3%) had underlying diseases. The lesions were multiple in five patients (33.3%) and a total of twenty-four muscle abscesses, including eleven extrapelvic and thirteen intrapelvic, were identified. When comparing extra- and intrapelvic pyomyositis, intrapelvic pyomyositis presents a diagnostic challenge requiring a high index of suspicion. Distinct clinical features such as local heat and painful swelling were all identified in extrapelvic pyomyositis, but they rarely (in only two of the thirteen lesions) emerged in intrapelvic pyomyositis. The average time from presentation to diagnosis was significantly longer in intrapelvic than in extrapelvic pyomyositis (1.4 vs 9.7 days). Although aspiration showed a high diagnostic rate in extrapelvic muscle abscesses, it was difficult to perform and was occasionally misinterpreted in intrapelvic cases. Routine X-rays were not helpful in making the diagnosis. CT scan was valuable because it provided positive diagnostic findings in all twelve patients who received one. The causative organisms in our patients were Staphylococcus aureus in eight (53.3%), Escherichia coli in three (20%), and Klebsiella in three (20%). Treatments consisted of parenteral antibiotics for all patients, image-guided aspiration in four patients, and surgical drainage in eleven patients. Two intrapelvic pyomyositis patients expired due to sepsis. At the completion of the study, twelve patients were asymptomatic without sequel, and one patient had a recurrence.

Peritoneal scintigraphy for diagnosing periumbilical leakage in a patient on continuous ambulatory peritoneal dialysis.

Continuous ambulatory peritoneal dialysis (CAPD) offers several advantages over hemodialysis for patients with end-stage renal disease; however, this technique also includes many documented complications. A case with clinical suspicion of dialysate leakage on CAPD was investigated by peritoneal scintigraphy using technetium-99m macroaggregated human albumin (99mTc-MAA). Peritoneal scintigraphy showed radiotracer accumulation over the periumbilical area at 2 hours 30 minutes after intraperitoneal infusion of 99mTc-MAA. Six hours of imaging revealed more apparent radioactivity at the same site. This study is to illustrate the simple diagnostic helpfulness of peritoneal scintigraphy in a patient with a CAPD-related structural defect.

Peritoneoscintigraphy using Tc-99m MAA for diagnosis of diaphragmatic disruption in a peritoneal dialysis patient.

Massive hydrothorax is an infrequent but well-recognized complication of continuous ambulatory peritoneal dialysis (CAPD), and is often regarded as a contraindication to its use. We describe here a patient with massive hydrothorax that appeared during CAPD. Peritoneoscintigraphy was performed to demonstrate the clinical suspicion of a pleuroperitoneal communication and the pleurodesis using tetracycline was commenced and this allowed the successful continuance of CAPD.

Alzheimer's disease: scintigraphic appearance of Tc-99m HMPAO brain spect.

UNLABELLED: To investigate the value of Tc-99m hexamethylpropylene amine oxime (Tc-99m HMPAO) single photon emission computed tomography (SPECT) as a diagnostic test for Alzheimer's disease. METHODS AND PATIENTS: Tc-99m HMPAO SPECT was performed on 140 patients and 20 controls. A final diagnosis was established for 115 patients, 58 of whom had Alzheimer's disease. The probability of AD was determined for seven scintigraphic patterns. The probability of Alzheimer's disease was 14% for patients with memory loss and normal perfusion. For patients with abnormal perfusion patterns, the probability of Alzheimer's disease was 87% with bilateral temporoparietal defects, 73% with bilateral temporoparietal defects plus additional defects, 62% with a unilateral temporoparietal defect, 33% with a frontal defect only, 0% with other large defects, and 0% with multiple small cortical defects. In 115 patients with the complaint of memory loss or cognitive abnormalities, bilateral temporoparietal hypoperfusion with or without additional hypoperfusion was more frequent than other scintigraphic patterns in patients with Alzheimer's disease. Tc-99m HMPAO SPECT offers the clinician the possibility of differentiating dementias on the basis of differences in perfusion patterns.