Two-dimensional Shear Wave Elastography: Utility in Differentiating Gallbladder Cancer From Chronic Cholecystitis.

OBJECTIVE: To study the utility of 2D shear wave elastography (SWE) and ascertain cut-off values of shear wave elasticity (SWe) to differentiate benign and malignant thickening of the gallbladder wall. METHODS: This study was a prospective study of patients with symptomatic gallstone disease (GSD, n = 51) and gallbladder cancer (GBC, n = 46) and controls without any biliary disease (n = 46). All the participants underwent 2D USG and SWE of the gallbladder. Grey-scale ultrasound and SWE were done in the different regions in the gallbladder. RESULTS: The median age of the patients with GSD was 49 years (interquartile range [IQR]: 33-55), GBC was 55 years (IQR: 46-65), and controls was 37 years (IQR: 27-48.25). In patients with GBC, asymmetrical mural thickening was the predominant imaging pattern (n = 24, 52.2%). The mean SWe of the abnormal area in GBC (34.99 ± 17.77 kPa [n = 46]) was significantly higher than that of the uninvolved region (18.27 ± 8.12 kPa [n = 35]; P < .01). The mean SWe of the uninvolved region in GBC (18.27 ± 8.12 kPa [n = 35]) was also significantly higher (P < .01) than that of GSD (12.27 ± 4.13 kPa [n = 51]) and controls (10.52 ± 3.75 kPa [n = 46]). On ROC analysis, AUC of 0.927, at a cut-off of 20 kPa, sensitivity was 91.3%, specificity was 83.5%, positive likelihood ratio was 5.54, and negative likelihood ratio was 0.10 to diagnose GBC. CONCLUSION: The 2D SWE is a reliable adjunctive tool to grey-scale USG in differentiating the malignant from benign gallbladder wall and may help to pick up early malignancy in GSD.

Safety and Diagnostic Yield of 68Ga Prostate-specific Membrane Antigen PET/CT-guided Robotic-assisted Transgluteal Prostatic Biopsy.

Background Transrectal US-guided biopsy with or without MRI fusion is performed for diagnosing prostate cancer (PCa) but has limitations. Gallium 68 (68Ga) prostate-specific membrane antigen (PSMA) PET/CT-guided targeted biopsy has the potential to improve diagnostic yield of PCa. Purpose To evaluate the safety and diagnostic yield of 68Ga PSMA PET/CT-guided, robotic-arm assisted transgluteal prostatic biopsy. Materials and Methods In this single-center nonrandomized prospective trial, participants with a clinical suspicion of PCa (serum prostate-specific antigen level > 4 ng/mL) were recruited from January 2019 to September 2020. After whole-body 68Ga PSMA PET/CT, participants with PSMA-avid intraprostatic lesions underwent PET-guided transgluteal biopsy by using an automated robotic arm. To assess safety and diagnostic yield, procedure-related complications and histopathologic results were documented. Pain during the procedure was scored by a visual analog scale. Descriptive statistics were applied; qualitative variables were reported in percentages. Results Seventy-eight participants (mean age, 66 years ± 7 [standard deviation]; 36 participants [46%] with prior negative results at transrectal US-guided biopsy) were enrolled. Fifty-six (72%) participants had PSMA-avid lesions (prior negative results at transrectal US-guided biopsy in 22 of 56 [39%]) and underwent targeted biopsy. PCa was confirmed in 54 of 56 (96%) participants, and clinically significant PCa (Gleason score ≥ 7) was confirmed in 24 of 54 (44%). Two participants had nonrepresentative samples that required rebiopsy. All participants experienced pain during the procedure, mild (median visual analog scale score, 1; interquartile range, 1-2) in 36 of 56 (64%) and moderate (median visual analog scale score, 5; interquartile range, 5-6) in 20 of 56 (36%). Postprocedure complications were noted in five of 56 (9%) participants and were minor (hematuria, four participants; hematospermia, one participant; and gluteal pain, two participants). No participant developed a postprocedural infection. Conclusion Transgluteal prostate-specific membrane antigen (PSMA) PET/CT-guided, robotic-targeted prostatic biopsy is safe with a high diagnostic yield of prostate cancer for PSMA-avid lesions. Clinical trial registration no. NCT05022576 © RSNA, 2022.

Outcome Analysis of Reduction and Nonreduction Dismembered Pyeloplasty in Ureteropelvic Junction Obstruction: A Randomized, Prospective, Comparative Study.

Objectives: The objective of this study is to compare the changes in renal function and drainage following open dismembered pyeloplasty with and without renal pelvis reduction. Materials and Methods: Randomized prospective study of children with ureteropelvic junction obstruction undergoing pyeloplasty with (Group 1) and without (Group 2) pelvis reduction over an 18-month period. Postoperative function and drainage were assessed by ethylene dicysteine (EC) scan and intravenous urography (IVU) and renal pelvis size by ultrasonography. Results: Forty-two patients (2 months-11 years) participated. The mean preoperative EC scan function was Group 1: 45.88% ± 14.42% (5%-80%) and Group 2: 39.22% ± 9.75% (21%-53%). (P = 0.117). The mean postoperative EC scan function of Group 1 was 42.64% ± 9.62% (17%-54%) and 43.75% ± 9.88% (17%-58%) and of Group 2 was 44.77% ± 12.82% (20%-68%) and 42.25% ± 8.56% (23%-58%) at 3 months (P = 0.584) and ≥ 1year (P = 0.385), respectively, with no significant difference. None required re-do pyeloplasty. The number of patients with slow drainage, especially at 3 months and also at ≥1-year postoperative period on EC scan was slightly higher in Group 2 compared to Group 1 but did not attain statistical significance. There was postoperative improvement in function and drainage on IVU with no significant difference between the two groups, (P = 0.214; P = 0.99, respectively). At a mean follow-up of 45.5 months, Group 2 also showed significant reduction in pelvis size on ultrasound (P = 0.011). Conclusion: Postoperative function remained stable in both groups. More number of patients achieved unobstructed drainage by 3 mo postoperative after reduction pyeloplasty but drainage patterns were mostly similar between reduction and nonreduction of pelvis group in late follow-up.

Fluorodeoxyglucose positron emission tomography/computed tomography in the diagnosis, assessment of disease activity and therapeutic response in relapsing polychondritis.

OBJECTIVE: To evaluate 18F-fluorodeoxyglucose (FDG) PET/CT in the assessment of disease activity, extent of the disease and response to therapy in relapsing polychondritis. METHODS: Twenty-five patients (9 men, 16 women) with a mean age of 38.2 years (s.d. 13.7; range 18-62), diagnosed to have relapsing polychondritis according to Damiani and Levine's modification of McAdam's criteria, who underwent PET/CT examination were included. Ten patients underwent a second PET/CT examination after therapy or during follow-up. Clinical symptoms and auxiliary examination findings were recorded. PET/CT findings were reviewed and correlated with the clinical symptoms. RESULTS: The major symptoms were aural pain (n = 21), nasal pain (n = 10), stridor (n = 5), cough (n = 9), fever (n = 8) and laryngeal tenderness (n = 8). The initial PET/CT was positive in 23/25 patients. PET/CT revealed involvement of auricular (n = 14), nasal (n = 8), laryngeal (n = 7), tracheobronchial (n = 6) and Eustachian (n = 3) cartilages with a mean maximum standardized uptake value (SUVmax) of 4.1 (s.d. 2.5; range 1.7-12.7). Fair correlation of aural/nasal pain/stridor with FDG avidity of cartilage involvement on PET/CT was noted. The key finding was detection of asymptomatic large airway involvement in seven patients (28%). Re-examination PET in 10 patients revealed complete therapeutic response (n = 5), partial response (n = 1), stable disease (n = 1), progressive disease (n = 1) and disease recurrence (n = 2). CONCLUSION: FDG PET/CT is a useful tool for the assessment of the disease activity and extent. It identified activity in clinically inaccessible sites that are of clinical significance. It is also useful in assessing treatment response and finding relapse.

Diagnostic performance of real-time robotic arm-assisted 18F-FDG PET/CT-guided percutaneous biopsy in metabolically active abdominal and pelvic lesions.

PURPOSE: To evaluate the feasibility and diagnostic performance of 18F-FDG PET/CT-guided biopsy of abdominal and pelvic lesions with automated robotic arm (ARA) assistance. METHODS: This prospective study included 114 patients (75 men, 39 women; mean age 51.3 ± 14.7 years, range: 18-90 years) who underwent PET/CT-guided biopsy of FDG-avid abdominal and pelvic lesions from October 2014 to December 2017. Of these patients, 54 had a prior inconclusive CT-guided biopsy. The biopsies were done with ARA assistance, and a real-time sample was obtained after confirming the position of the needle tip within the target lesion on PET/CT. Histopathology reports were reviewed to evaluate the diagnostic performance of the procedure. Clinical or imaging follow-up was done to confirm negative results. RESULTS: The lesions were successfully targeted in 110 of the 114 patients (96.5%) and yielded a pathological diagnosis. Pathological diagnoses were confirmed in 50 of the 54 patients with a prior inconclusive biopsy. Of the 110 lesions, 82 were malignant, 20 were benign, and 8 showed minimal residual FDG uptake at the end of treatment and had no active disease even on clinical and imaging follow-up of at least 3 months. Findings were true-positive in 102 lesions, false-positive in none, true-negative in eight and false-negative in four. The procedure showed sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 96.2%, 100%, 100%, 66.7 and 96.5%, respectively. No immediate complications or delayed life-threatening events were observed. CONCLUSION: Percutaneous biopsy of metabolically active abdominal and pelvic lesions with ARA assistance is a technically feasible, safe and accurate method for pathological diagnosis with high diagnostic performance. PET-guided biopsy is highly practical and useful in patients, especially in those with a previous inconclusive biopsy.

18F-FDG PET/CT-Guided Real-Time Automated Robotic Arm-Assisted Needle Navigation for Percutaneous Biopsy of Hypermetabolic Bone Lesions: Diagnostic Performance and Clinical Impact.

OBJECTIVE: The purpose of this study is to establish the feasibility, safety, diagnostic performance, and clinical impact of real-time intraprocedural 18F-FDG PET/CT-guided automated robotic arm-assisted biopsy of hypermetabolic marrow or bone lesions. SUBJECTS AND METHODS: This prospective study included 73 patients (47 male patients and 26 female patients) who underwent PET/CT-guided biopsy of accessible hypermetabolic marrow or bone lesions. The biopsy needle was inserted into the target lesion with automated robotic arm assistance, and tissue sampling was performed at the site with the highest metabolic activity, after the needle position was confirmed using PET/CT. The results of histopathologic examination and clinical and imaging follow-up examinations were reviewed. The referring physicians were interviewed to assess the clinical impact of interventions on treatment planning. RESULTS: Of the 73 patients assessed, 34 were oncology patients with suspected metastasis or residual disease. The pathologic diagnosis was not known for 38 patients with clinically suspected benign (n = 7) or malignant (n = 31) disease. The remaining patient was suspected of having skeletal sarcoidosis. Thirty-nine marrow lesions and 34 bone lesions were targeted. All procedures were technically successful and safe, and no major complication was observed. Pathologic diagnosis was confirmed for 72 patients, for a diagnostic yield of 98.6%. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for the detection of malignancy (n = 54) were 98.2%, 100%, 100%, 94.7%, and 98.6%, respectively. The procedure was helpful in determining the treatment plan for 91.7% of patients. CONCLUSION: Automated robotic arm-assisted FDG PET/CT-guided real-time bone biopsy is a feasible and safe intervention with a very high diagnostic yield. It had a major clinical impact on patients with minimal residual FDG uptake on end-of-treatment PET/CT and isolated suspected metastatic lesions.

Non traumatic vertebral lesions: incremental utility of PET-CT over MRI and FNAC in a suggested diagnostic algorithm.

OBJECTIVE: To prospectively compare positron emission tomography-computed tomography (PET-CT) with conventional magnetic resonance imaging (MRI) and FNAC for diagnosis of non- traumatic vertebral lesions fracture in countries like India where tuberculosis is endemic. METHODS: Fifty four patients with non-traumatic spontaneous vertebral lesions were prospectively studied. All patients underwent CEMRI focusing on the spinal lesions, whole-body PET-CT and FNAC.Results were then analysed and compared with final diagnosis obtained either by FNAC or clinical follow up. RESULTS: Out of total 54 patients, FNAC from the spinal lesion could establish diagnosis in 36 patients (26 TB, 1 Fungal and 9 tumors). Of the remaining 18 patients, diagnosis could be established in 7 utilizing FNAC from other sites as dictated by PET-CT. In the remanining11 patients, the diagnosis and management was decided on the concordance of MRI and PET-CT. CONCLUSION: All three investigations have their own advantages and pitfalls and they complement each other in reaching the final diagnosis. MRI has a better pick up rate (than PET-CT) for inflammatory lesions. PET-CT on the other hand has better sensitivity for malignant vertebral disease. Diagnosis was established if FNAC was conclusive. In cases where FNAC was inconclusive, an additional 38.9% patients' diagnosis could be established by FNAC from other sites of involvement as dictated by PET-CT. This was an incremental utility of PET-CT. When even this fails, there were two possible scenarios-MRI and PET-CT in concordance with each other. In such a scenario, the combined report of MRI and PET-CT was relied upon. The last sub group (where MRI and PET-CT were discordant and FNAC was inconclusive) still remains achilles' heel. Wide bore biopsy may help in establishing diagnosis in such group.

Scintigraphic findings in end-stage liver disease on Tc-99m sestamibi SPECT/CT myocardial perfusion imaging.

Technetium-99m sestamibi myocardial perfusion imaging is commonly employed non-invasive study for evaluation of coronary artery disease; however, incidental extracardiac scintigraphic findings observed may provide additional diagnostic information. The authors present the unusual scintigraphic findings in a case of decompensated liver disease with right hepatic hydrothorax, being planned for orthotopic liver transplant.

Role of Positron Emission Tomography in Assessing Disease Activity in Ulcerative Colitis: Comparison with Biomarkers.

BACKGROUND: Disease activity in ulcerative colitis (UC) is best assessed clinically by Mayo score. 18-Fluorodeoxyglucose positron emission tomography-computerized tomography (FDG PET-CT) is a noninvasive imaging technique to assess extent, disease activity and response to treatment of UC, especially in high risk population or patients unwilling for endoscopy. AIMS: We conducted a prospective observational study with the aim of assessing and correlating UC disease activity by clinical criteria, endoscopy, histology, serum and fecal biomarkers, and FDG PET-CT. METHODS: Sixty eligible patients of UC were enrolled into three groups (26 remission, 24 moderate and 10 severe activity) as per Mayo score and FDG PET-CT was performed within 72 h of colonoscopy. ESR, CRP, and fecal calprotectin (FC) levels were determined for all patients. RESULTS: Of 60 enrolled patients, 10% patients had proctitis, 43.3% left-sided colitis, and 46.7% extensive colitis. ESR, CRP, FC levels, and rectal PET activity were significantly higher in groups with moderate and severe disease activity. Rectal PET activity showed a significant correlation with the Mayo score (k = 0.465, p < 0.001), endoscopic subscore (k = 0.526, p < 0.001), histological score (k = 0.496, p < 0.001), and FC (k = 0.279, p = 0.031). Extent evaluation by FDG PET-CT and colonoscopy showed a significant correlation (k = 0.582, p < 0.001). Besides, FDG PET-CT identified sacroiliitis in one patient and adenocarcinoma in one patient. CONCLUSION: FDG PET-CT is a reliable noninvasive tool for detection of disease activity, extent in UC with good correlation with Mayo score, histology and fecal biomarkers and accurate predictor of disease remission.

Chylocolporrhea or chylous vaginal discharge: diagnostic conundrum with therapeutic challenge.

BACKGROUND: Chylocolporrhea or chylous vaginal discharge is an extremely rare manifestation of chylous reflux syndrome. Continuous loss of chyle adversely affects quality of life and results in increased morbidity due to the chronic loss of nutrients. Diagnosis and management of this condition is very challenging. CASE HISTORY: A 35-year-old multiparous lady presented with the chief complaints of excessive milky vaginal discharge for 10 years. Microscopic and biochemical analysis of vaginal discharge along with hysteroscopy confirmed diagnosis of chylocolporrhea. Lymphoscintigraphy along with magnetic resonance imaging revealed site of leakage from the right external iliac lymphatics. She was started on medium-chain triglycerides-rich diet and meticulous ligation of all visible megalymphatics with tension-free lymphovenous anastomosis was done to right external iliac vein. CONCLUSION: Chylocolporrhea can be managed successfully using operative and nonoperative modalities.

Comparison of Tc-99m tetrofosmin myocardial perfusion scintigraphy and exercise F18-FDG imaging in detection of myocardial ischemia in patients with coronary artery disease.

BACKGROUND: Direct ischemia imaging with F18-FDG can potentially overcome many limitations of SPECT-MPS inherent to "cold imaging". We compared SPECT-MPS with exercise F18-FDG PET in detection of ischemia in patients with suspected CAD. METHODS: 45 patients with clinical suspicion of CAD without the history of myocardial infarction were prospectively included. All patients underwent Tc-99m tetrofosmin SPECT-MPS and exercise F18-FDG PET imaging within 7 days of SPECT-MPS, and both modalities were compared with coronary angiography for detecting ischemia. RESULTS: 27 patients had an abnormal coronary angiography (at least one coronary artery with stenosis >50%). Exercise F18-FDG performed better than SPECT-MPS in LAD and LCX territory with comparably good performance in RCA territory. Exercise F18-FDG performed better in single-vessel disease and equally good in multi-vessel disease compared to SPECT-MPS. Performance of exercise 18F-FDG study was significantly better than SPECT-MPS (P = .0014) in the analysis of the 81 vascular territories in the 27 patients with abnormal coronary angiography. Performance of exercise F18-FDG was significantly better than SPECT-MPS in detecting ischemia in suspected CAD patients. CONCLUSION: Exercise F18-FDG imaging is a potentially useful ischemia imaging modality which offers the advantages of direct ischemia imaging in CAD patients.

Metabolic signatures of malignant and non-malignant mass-forming lesions in the periampulla and pancreas in FDG PET/CT scan: an atlas with pathologic correlation.

Positron emission tomography (PET) has been used for the characterization of pancreatic and periampullary lesions. Pancreatitis-associated inflammation affecting only a portion of the pancreas gives the appearance of a mass lesion on imaging. Consequently, the differential diagnosis between cancer and pancreatitis becomes a commonly encountered problem. Traditionally, PET was interpreted as positive (to denote malignancy) if fluorodeoxyglucose (FDG) activity in the pancreas exceeded background activity and as negative (to denote benign) if activity was less than or equal to background activity. However, the specificity was limited with this method of interpretation. A relatively wide overlap has been reported between semiquantitative uptake values obtained in cancers and those in inflammatory lesions. Also, the qualitative (metabolic patterns) and quantitative variables (standardized uptake values) have been complementary and at sometimes controversial to each other in various clinical situations. There is paucity of data in the literature highlighting the role of FDG PET/CT in characterization of such mass lesions. The primary aim of this pictorial review is to list the various pathologic processes of pancreas and periampulla that could be studied with FDG PET/CT and recognize the different FDG uptake patterns and apply this information to characterize the different lesions affecting the pancreas and periampulla. We have also discussed the limitations of conventional imaging and advantages of FDG PET/CT for the evaluation mass-forming lesions of the pancreas and periampulla.

Diagnostic accuracy of F-18 FDG PET/CECT vs. CECT for detecting recurrence of periampullary carcinoma and its prognostic significance.

PURPOSE: To evaluate the additive value of whole-body F-18 fluoro-deoxyglucose positron emission tomography (FDG PET) as an adjunct to contrast-enhanced computed tomography (CECT) for detecting recurrence following Whipple's resection for periampullary carcinoma and to analyze the prognostic significance of FDG PET-/CECT-based detection of recurrence. METHODS: Fifty patients (34 males, 16 females; mean age: 55 ± 11 years) who underwent PET/CECT following resection of periampullary carcinoma were included. The study was duly approved by the institutional ethical committee for retrospective analysis of the data. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of FDG PET/CECT and CECT alone for detection of recurrence were calculated, and the accuracy was compared with ROC analysis. The prognostic factors for survival following recurrence were analyzed by univariate and multivariate methods. RESULTS: PET/CECT indicated recurrence of disease in 26 (52%) patients. The overall mean survival time was 46 months with an overall survival rate of 42%. The sensitivity, specificity, PPV, NPV and accuracy of PET/CECT and CECT for detection of recurrence were 96.1%, 91.6%, 92.6%, 95.6%, 94% and 76.9%, 75%, 76.9%, 75%, 76%, respectively (p = 0.037). Also change in management could have been achieved in 18% of patients based on the PET/CECT results. In univariate analyses, SUVmax >7.3 was the only predictor of poor survival (p < 0.05). CONCLUSION: PET/CECT could be used as a one-stop imaging tool for staging and prognostication of recurrent periampullary carcinoma that could result in better patient management.

Function and size of the residual kidney after treatment of Wilms tumor.

Long-term damage to the residual kidney is of concern in the survivors of Wilms tumor. Our objective was to evaluate the long-term glomerular function and size of the residual kidney in these patients. Twenty-nine survivors of Wilms tumor diagnosed between July 1999 and June 2004 were enrolled. The glomerular function was assessed by creatinine clearance, 99mTc DTPA radionuclide scintigraphy and 24-hour urinary protein. Renal size was evaluated by ultrasonography. Median age at diagnosis and at enrollment were 2.87 ± 1.8 (range: 0.5-7.5) and 7.9 ± 3.8 years (range: 2.5-18). Median duration of follow-up was 4.78 ± 2.6 years (range: 1-8.8). Evidence of renal dysfunction in the form of either function or size was identified in eight (27.6%) children. Six children had subnormal glomerular filtration rate and one had proteinuria. Subnormal size of the residual kidney was observed in one child. Age at diagnosis, stage, and duration elapsed after nephrectomy had no association with renal dysfunction (P >.05). Long-term follow up is crucial to identify clinical nephrotoxicity among survivors of Wilms tumor.

Role of N-13 ammonia PET/CT in diagnosing pancreatic necrosis in patients with acute pancreatitis as compared to contrast enhanced CT--results of a pilot study.

BACKGROUND: Contrast enhanced computerized tomography (CECT) is used to determine severity of acute pancreatitis based upon the presence and extent of necrosis. However limitations do exist precluding its applicability in renal failure. Positron emission tomography (PET) imaging for cardiac perfusion shows good uptake of N-13 ammonia ((13)NH3) metabolites in pancreas owing to high perfusion. AIM: To evaluate the role of (13)NH3 PET/CT in acute pancreatitis and compare it with CECT in diagnosing and quantifying pancreatic necrosis. MATERIAL AND METHODS: Patients presenting within 1 week of acute pancreatitis were studied. Static PET images were acquired after intravenous injection of 370-740 MBq of (13)NH3. (13)NH3 PET/CT was followed by CECT in the absence of renal impairment. Maximum standard-uptake-value (SUVmax) of pancreas (P) and liver (L) were taken and their ratio (P/L) was estimated to determine perfusion. Areas within pancreas with no tracer uptake were considered necrotic. These patients were managed as per institutional protocol. Patients undergoing (13)NH3 PET/CT for coronary artery disease were used as controls. RESULTS: 29 patients (72% males) were studied of whom 6 had elevated serum creatinine. (13)NH3 PET/CT was done in all patients along with 9 controls while CECT was carried out after PET/CT in 23 patients. Median levels of SUVmax (P/L) in the controls, uninvolved pancreas and necrotic areas were 1.0 (0.86-1.03), 0.66 (0.50-0.92) and 0.12 (0.07-0.21) respectively (p < 0.001). Necrosis estimation was similar in 22/23 patients without renal failure while in one patient only (13)NH3 PET/CT picked up necrosis (<30%). 5/6 patients with renal failure had necrosis on (13)NH(3) PET/CT which was confirmed on surgery or subsequent CECT after improvement of renal failure. CONCLUSION: This pilot study is the first in literature to diagnose necrosis in patients with acute pancreatitis using (13)NH3 PET/CT. With minimal additional radiation burden, it is possible to estimate the absolute tissue perfusion as well. With no adverse renal side effects, this can be an alternative to CECT in patients with renal failure giving similar information. It has good agreement with CECT with a good interobserver acceptability.

F-18 FDG PET/CT in the evaluation of Takayasu arteritis: an experience from the tropics.

OBJECTIVE: To evaluate the performance parameters of FDG PET/CT in patients with Takayasu arteritis at diagnosis and during immunosuppression. METHODS: Retrospective analysis of 60 FDG PET/CT studies in 51 patients was performed (17 scans at diagnosis out of which 4 had follow-up scans also and 43 scans on immunosuppression). The degree of FDG uptake in the vessels was assessed visually using a 4-point scale and maximum standardized uptake value (SUVmax), SUVratio, extent of vasculitis and association with ESR were calculated. RESULTS: PET/CT was positive for active vasculitis in all 17 patients at diagnosis. The mean SUVmax and mean SUV ratio of the active areas were 5.1 ± 3.0 and 3.2 ± 1.9, respectively. On immunosuppression, PET scan was positive for active vasculitis in 14/43 (32.5%) scans. The mean SUVmax and mean SUVratio of the active areas were 1.7 ± 2.1 and 0.95 ± 1.2, respectively. There was significant difference between the mean SUVmax and mean SUVratio at diagnosis and on immunosuppression, respectively (P < .01). The median number of vascular segments in each uptake grade group was also statistically different (P < .01) between scans at diagnosis and on immunosuppression. The median ESR level in PET positive scans was 29 mm/hour (2-53), whereas in PET negative scans was 35.5 mm/hour (6-50) and the difference was not statistically significant. CONCLUSION: FDG PET/CT showed good sensitivity to detect active vasculitis at diagnosis and during immunosuppression. The change in SUVmax between the successive FDG PET/CT scans may give an objective assessment of response to immunosuppression.

Effect of gender, biochemical parameters & parathyroid surgery on gastrointestinal manifestations of symptomatic primary hyperparathyroidism.

BACKGROUND & OBJECTIVES: Information on gastrointestinal manifestations and then response after curative parathyroid surgery is scarce in symptomatic primary hyperparathyroidism (PHPT). This study was carried out to analyse gastrointestinal manifestations in patients with PHPT and their associations with biochemical parameters. METHODS: This retrospective study included 153 patients with symptomatic primary hyperparathyroidism (PHPT). The signs and symptoms pertaining to gastrointestinal system were analyzed. The difference of symptoms between men and women and difference in biochemical parameters in presence of different symptoms were evaluated. The relationship between serum calcium, phosphate and parathyroid hormone (PTH) levels with presence of gallstone and pancreatitis was also studied. RESULT: Of the 153 patients, 46 (30%) were men. The mean age was 39.2 ± 13.9 yr. Nearly 80 per cent of PHPT patients had at least one symptom/ sign related to gastrointestinal system. The most common gastrointestinal manifestations were abdominal pain 66 (43%), constipation 55 (36%), and nausea/or vomiting 46 (30%). Nearly one-fourth 34 (22%) of patients had a history of either gallstone disease or cholecystectomy or both. The prevalence of gallstone disease was higher in women (P<0.05). Imaging and biochemical evidence of pancreatitis was found in 27 (18%) patients. Pancreatitis was more common in men compared to women (P<0.05) despite the higher prevalence of gallstones in women. Serum calcium, phosphate or PTH levels were not associated with high risk for gallstone disease, however, serum calcium (P<0.05) was associated with 1.3 times higher risk of developing pancreatitis. In majority of patients, gastrointestinal manifestations resolved within three months of curative parathyroidectomy. Except two patients, none had recurrence of pancreatitis. INTERPRETATION & CONCLUSIONS: The study revealed that the gastrointestinal symptoms were common in patients with symptomatic PHPT. There was not much gender difference in gastrointestinal symptoms except higher occurrence of gallstones in women and pancreatitis in men. There was no difference in biochemical profile between those who had and did not have gastrointestinal symptoms.

Evaluation of skull bone viability and effect of early surgical intervention in electrical contact burns using 18 F-Sodium Fluoride PET-CT imaging.

OBJECTIVE: Electrical contact burns of the scalp cause serious morbidity and mortality. Early necrotic bone debridement and flap cover are crucial for successful wound closure. 18 F Sodium Fluoride (NaF), with high bone-to-soft tissue activity ratio, is useful for bone viability assessment. This study evaluated the role of 18 F NaF PET-computed tomography (CT) in objectively defining the extent and depth of nonviable calvarial bone, to guide adequate bone debridement. METHOD: Of 20 patients referred to our institute with electrical contact burns of the scalp during a 2-year period, 15 were enrolled in the study. Two weeks after the initial management, tracer uptake pattern was noted on 18 F NaF PET-CT of the head and exposed bone measured. Surgical bone debridement was based on scan findings, followed by wound closure. All patients underwent clinical evaluation and follow-up scan 3 months after surgery. RESULTS: Eight patients showed a central photopenic area in the exposed bone (maximum standardized uptake value [SUVmax] of 0.76 ± 0.14 with mean maximum dimensions 4.10 ± 1.76/2.67 ± 1.54 cm). High tracer uptake (SUVmax, 9.66 ± 6.03) was seen peripheral to the exposed bone (mean maximum dimensions, 8.14 ± 3.03/4.75 ± 1.61 cm). Postoperatively, there was no significant change in tracer uptake in the central debrided region or peri-debridement bone area under the flap. Clinically all patients showed a well-healed flap. CONCLUSION: 18 F NaF PET-CT appears useful for objective evaluation of skull bone viability and planning necrotic bone debridement in patients with electrical contact burns. However, additional studies with longer patient follow-up are required to validate these results.