Indian Journal of Nuclear Medicine最新文献

Purpose: The purpose of the study was to compare the stability and homogeneity of various routinely used meals for gastric emptying scintigraphy (GES) for solids and to validate an improved vegetarian well uniformly radiolabeled solid meal for GES, which is easily fully consumed by patients in view of their common symptoms in such indications and in keeping with Indian food culture.

Materials and methods: Following various types of solid meal preparations were labeled with 3 mCi of 99 mTc sulfur colloid (SC), and image of each meal was acquired on General Electric (GE) Infinia Hawkeye 4 camera: (1) Meal of 4 slice bread + 20 g butter with calorific value ≈ 356 kcal. (2) 4 slice bread + 30 g jam with calorific value ≈ 332 kcal. (3) 4 slice bread + 70 ml of milk with calorific value ≈ 243 kcal. (4) 150 g of sagu (sabudana) +5 ml refined vegetable oil + 10 g peanuts (sagu khichdi) with calorific value ≈ 324 kcal. (5) 4 idli + 2 tablespoon green chutney with calorific value ≈ 280 kcal. (6) 70 g wheat + 50 ml water + 5 ml refined vegetable oil with calorific value ≈ 237 kcal. (7) Meal of 75 g of idli mix + 80 ml water + 10 g butter with calorific value ≈ 310 kcal. All radiolabeled meals were subjected to the radiolabeled stability test procedure to calculate labeling efficiency which was compared.

Results: Idli meal prepared with radiotracer added to the batter mixture itself, with a calorific value ≈ 310 kcal showed the highest uniform Tc99 m SC distribution in comparison to all other meal preparations.

Conclusions: Radiolabeled idli (savory cake) prepared with radiotracer added to the batter mixture itself, appears to be an ideal vegetarian meal in comparison to all other meal preparations for gastric emptying scintigraphy studies, especially among patients with specific dietary restrictions.

Differentiated thyroid carcinoma (DTC) metastasizing to the adrenal glands is very infrequent. We present three cases of DTC with adrenal metastasis in their follow-up, in which two were from follicular thyroid carcinoma and one from papillary thyroid carcinoma along with review of literature to emphasize the role of cross-sectional and correlative imaging in DTC with adrenal metastasis.

A 48-year-old female, a known case of ulcerative colitis, on routine workup, was incidentally detected to have biochemical hyperthyroidism. ^99mTc pertechnetate thyroid scintigraphy performed for the evaluation of hyperthyroidism revealed two foci of increased tracer uptake in the right thyroid lobe with suppressed uptake in the rest of the thyroid gland consistent with dual autonomously functioning thyroid nodules.

Fetal type adenocarcinoma (FTA) is a rare malignant tumor of the lung that histologically resembles an embryonic lung. Due to its rarity, no studies had investigated the possible role of the ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography ([¹⁸F]FDG PET/CT) in the initial assessment and/or in the restaging of the disease yet. We present a case of a male patient with tongue carcinoma and incidental findings of well-differentiated FTA at [¹⁸F]FDG PET/CT. The patient was treated by specific therapy and also performed a subsequent [¹⁸F]FDG PET/CT scan that showed a significant reduction of the uptake on lung lesion. This case highlights the potential role and usefulness of PET imaging for staging and posttherapeutic restaging of well-differentiated FTA. The review of the available literature underlined the rarity of the disease since only seven reports were present. Anyway, a possible role of the [¹⁸F]FDG PET/CT in the staging of FTA is conceivable.

Aim of the study: This study aims to study the utility of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) findings in the initial staging and management of patients with esophageal carcinoma.

Materials and methods: In this prospective study, we evaluated 74 patients with a mean age of 59.4 ± 11.6 with a range of 35-86 years. Comparison between the mean and standard deviation of SUV_max of primary tumor between two histopathological groups, squamous cell carcinoma (SCC) and adenocarcinoma (AC) was done using unpaired Student's t-test. The mean of SUV_max of primary tumor in relation to localized tumor to nodal to distant metastases was assessed by ANOVA test. P <0.05 was considered statistically significant. The extent of agreement between findings of contrast-enhanced computed tomography (CECT) chest and abdomen and ¹⁸F-FDG PET/CT was done using Cohen's kappa coefficient (κ).

Results: Among total n = 74 (42 males and 32 females with mean age 59.4 ± 11.4; range 35-86 years) patients, SCC was seen in 78.4% and AC in 21.6% of patients. There is a progressively increased SUV_max value of primary tumor with nodal and distant metastases. ¹⁸F-FDG PET/CT showed disease of Stage I-II in 12.1%, Stage III in 20.2%, Stage IVA in 25.6%, and Stage IVB in 41.8% patients. There is agreement between ¹⁸F-FDG PET/CT and CECT chest and abdomen in the evaluation of regional lymph nodes (37.8% vs. 36.4%; κ - 0.96), nonregional lymph nodes (24.3% vs. 20.2%; κ -0.74), and distant organ involvement (21.6% vs. 17.5%; κ -0.82). In addition, ¹⁸F-FDG PET/CT found synchronous malignancies in 4.0% of patients.

Conclusion: ¹⁸F-FDG PET/CT metabolic parameters help in identifying metastatic involvement in morphologically equivocal and clinically suspicious lesions in carcinoma esophagus patients. Being a whole-body imaging modality, ¹⁸F-FDG PET/CT has inbuilt advantage to detect occult, distant metastases, and synchronous malignancies for effective staging and improving plan of clinical management.

Generally after the accreditation of the gamma camera, its unfailing optimal operation is guaranteed with established departmental preventive maintenance schedules. However, it is not easy to always religiously follow the same maintenance routines. Therefore, instead of preventive maintenance schedule, a reactive maintenance schedule was adopted in our department for a short span of time. In our center, the humidity level in the gamma camera room was recorded to be 90%, which was much higher than the recommended value of 50%-60%. This was due to the inundated water in the gamma camera room due to an accidental breakage of fire-extinguishing water pipeline, adjacent to the room. Postaccident, higher values of nonuniformity (both intrinsic and extrinsic uniformity) were observed. The reactive maintenance was undertaken by medical physicist and field engineer to record and confirm the crystal hydration in the detector and to restore the system for the clinical studies. The digital workflow program successfully rectified the problem of crystal hydration. It is highly recommended to perform timely reactive action which may prevent the permanent damage to the systems.

Isolated liver metastasis from prostate cancer is exceedingly rare. Prostate-specific membrane antigen-positron emission tomography/computed tomography has become the one-stop shop imaging in prostate cancer, but the uptake is a relatively nonspecific tracer and its expression can be seen in a plethora of nonprostatic solid tumors. We report one such example of an oligometastatic prostate cancer who presented with an isolated liver lesion which turned out to be an incidental hepatocellular carcinoma, thus representing a potentially unique diagnostic challenge.

Thyroid storm is an acute life-threatening complication of hyperthyroidism that presents with multisystem involvement. It can be precipitated by radioiodine therapy in high-risk patients. It has become less frequent, as current therapeutic approaches (antithyroid drugs and beta blockers) prevent the impact of thyroid hormones on the cardiovascular and central nervous systems. Hence, there is a concern that this rare clinical entity is misdiagnosed and inadequately managed leading to fatal outcomes. We report an elderly female with thyrotoxicosis who presented 4 weeks postradioiodine ablation with thyroid storm emphasizing the challenges in prompt diagnosis and future prevention of this rare clinical entity.

Certain abdominal and pelvic malignancies present with sensory, motor or autonomic symptoms suggestive of nerve root involvement. Perineural spread of tumor is an emerging explanation of such presentations. This could be seen in carcinoma prostate. In this case report, we present one such case of carcinoma prostate with local recurrence and perineural spread of tumor causing unilateral sacral plexopathy. The patient presented with persistently elevated serum prostate-specific antigen and symptoms of lower backache and paraesthesia in the back of the thigh. On evaluation with Gallium-68 prostate-specific membrane antigen positron emission tomography/computed tomography (Ga-68 PSMA PET/CT), perineural spread of recurrent lesion to S2-S4 nerve roots was identified. The patient received radiotherapy for local recurrence and improved symptomatically and is under follow-up. Carcinoma prostate patients presenting with neurological symptoms should be carefully evaluated to rule out perineural spread of tumor. Ga-68 PSMA PET/CT has proven to be a useful modality in diagnosing such cases.