The Role of Hepatobiliary Scintigraphy as the Initial Investigative Modality for Significant Bile Leak following Laparoscopic Cholecystectomy.

INTRODUCTION: Currently, the rate of bile duct injury and leak following laparoscopic cholecystectomy (LC) is still higher than for open surgery. Diverse investigative algorithms were suggested for bile leak, shifting from hepatobiliary scintigraphy (HBS) toward invasive and more sophisticated means. We aimed to analyze the use of biliary scan as the initial modality to investigate significant bile leak in the drain following LC, attempting to avoid potential unnecessary invasive means when the scan demonstrate fair passage of nuclear substance to the intestine, without leak. METHODS: We have conducted a prospective non-randomized study, mandating hepatobiliary scintigraphy first, for asymptomatic patients harboring drain in the gallbladder fossa, leaking more than 50 mL/day following LC. Analysis was done based on medical data from the surgical, gastroenterology, and the nuclear medicine departments. RESULTS: Among 3,124 patients undergoing LC, significant bile leak in the drain was seen in 67 subjects, of whom we started with HBS in 50 patients, presenting our study group. In 27 of whom, biliary scan was the only investigative modality, showing fair passage of the nuclear isotope to the duodenum and absence of leak in the majority. The leak stopped spontaneously within a mean of 3.6 days, and convalescence as well as outpatient clinic follow-up was uneventful. In 23 patients, biliary scan that was interpreted as abnormal was followed by endoscopic retrograde cholangio-pancreatography (ERCP). However, ERCP did not demonstrate any bile leak in 13 subjects. In 17 patients, ERCP was used initially, without biliary scan, suggesting the possibility of avoiding invasive modalities in 7 patients. CONCLUSIONS: Based on a negative predictive value of 91%, we suggest that in cases of asymptomatic significant bile leak through a drain following LC, a normal HBS as the initial modality can safely decrease the rate of using invasive modalities.

Physiologic thymic uptake of 18F-FDG in children and young adults: a PET/CT evaluation of incidence, patterns, and relationship to treatment.

UNLABELLED: (18)F-FDG uptake in the thymus, mainly related to hyperplasia after chemotherapy, has been described. Thymic uptake can challenge the accurate assessment of cancer patients by (18)F-FDG imaging. The present study defines the incidence, patterns, and intensity of thymic (18)F-FDG uptake in relationship to age and time after treatment in a large cohort of patients. METHODS: A total of 559 consecutive (18)F-FDG PET/CT studies in 160 patients (86 men, 74 women; age, 3-40 y) performed at baseline, during treatment, at the end of treatment, and during follow-up were retrospectively reviewed. PET/CT studies were assessed for the presence or absence (T+ or T-, respectively), pattern, and intensity (SUVmax) of increased (18)F-FDG uptake in the anterior mediastinum, localized by the CT component to the thymus. The overall incidence of (18)F-FDG avidity in the thymus in relationship to the patient's age and time after treatment administration were statistically evaluated. RESULTS: There were 137 of 559 T+ studies (25%), with equal sex distribution. T+ studies were found in significantly younger patients (20.6 +/- 9.3 y vs. 27.4 +/- 8.4 y, P < 0.001). Most T+ patients (60%) showed an inverted V pattern of thymic uptake, with additional unilateral mediastinal extension in 24% and focal midline uptake in 16% of studies. T+ studies were encountered in 80% of patients younger than 10 y, compared with 8% of patients in the 31- to 40-y age group. There were 17% T+ studies at baseline, 6% during treatment, 8% at the end of treatment, and 27%-40% during follow-up. The average SUVmax of thymic (18)F-FDG uptake was 3.73 +/- 1.22. CONCLUSION: Thymic (18)F-FDG uptake was found in 28% of the present study population, more frequently after treatment. T+ patients were significantly younger. Thymic uptake was found in 73% of untreated patients up to the age of 13 y and in 8% of patients in the fourth decade of life. Knowledge of this age- and treatment-related incidence of physiologic thymic (18)F-FDG avidity can reduce the number of potential pitfalls in reporting PET/CT studies in cancer patients.

Kohler disease: diagnoses and assessment by bone scintigraphy.

Limping is a frequent occurrence in children and may be caused by various conditions, including trauma, inflammation, infection, and malignancy. Nontraumatic avascular necrosis of the tarsal bones should be included in the differential diagnosis. Accumulated data have supported the superiority of bone scans to radiography in the early diagnosis of avascular necrosis. Bone scintigraphy is a useful tool for investigating pain when symptoms, laboratory examinations, and radiography do not point to a specific diagnosis. In the early phase of disease, bone scans may demonstrate decreased tracer uptake (photopenic region), subsequently a hot area is seen during the reparative process. Although magnetic resonance imaging has important implications in the diagnosis of avascular necrosis, bone scintigraphy with its ready availability has a significant role as a primary tool in the evaluation of a limping child.

Lung uptake in a young patient with hypercalcemia who was found to have systemic lupus erythematosus.

We report the case of 19-year-old woman with severe hypercalcemia who was evaluated with a bone scan to exclude bone metastases. Increased uptake in both lungs was detected on the bone scan. The patient's final diagnosis was systemic lupus erythematous (SLE). There is no reported pattern of bone scanning in SLE, and diffuse lung uptake has not been reported in these patients.

Imaging of primary sternal osteomyelitis in a patient with Crohn's disease.

A 41-year-old man with known Crohn's disease presented with chest pain and fever. Plain film and CT of the chest were normal, but bone scan and gallium scans showed intense sternal uptake. Surgery revealed staphylococcal osteomyelitis of the sternum. Following appropriate antibiotic treatment, the patient's symptoms resolved and follow-up gallium scans became normal. This is the first report of the association of sternal osteomyelitis and Crohn's disease, although other sites have been described. Sternal osteomyelitis has a high morbidity and the index of suspicion for this condition must be high even in the face of initially negative imaging.

Super scan leading to definitive diagnosis in a patient with recurrent syncope.

A "super scan" pattern detected on bone scintigraphy usually indicates either metabolic bone disease or diffuse metastases. We report a rare case of a 45-year-old man with recurrent episodes of syncope of 10 years' duration in whom bone scintigraphy showed a super scan with an axial skeleton distribution of uptake. Bone marrow biopsy established the diagnosis of systemic mastocytosis. The few reports in the literature of super scans associated with systemic mastocytosis showed diffuse axial and appendicular increased uptake. The present case shows a super scan involving the axial skeleton, which led to the diagnosis of systemic mastocytosis.