Surgical challenge in situs inversus with dextrocardia and Lutembacher syndrome.

Situs inversus with dextrocardia and Lutembacher syndrome is a rare cardiac anomaly. It is associated with other complex cardiac anomalies and anatomical defects. A 30-year-old woman with this condition underwent mitral valve replacement and closure of a secundum atrial septal defect. We describe the surgical approach, position of the surgeon, and bicaval cannulation technique for this anatomical aberration.

Radioiodine Remnant Ablation: A Critical Review.

Radioiodine remnant ablation (RRA) is considered a safe and effective method for eliminating residual thyroid tissue, as well as microscopic disease if at all present in thyroid bed following thyroidectomy. The rationale of RRA is that in the absence of thyroid tissue, serum thyroglobulin (Tg) measurement can be used as an excellent tumor marker. Other considerations are like the presence of significant remnant thyroid tissue makes detection and treatment of nodal or distant metastases difficult. Rarely, microscopic disease in the thyroid bed if not ablated, in the future, could be a source of anaplastic transformation. On the other hand, microscopic tumor emboli in distant sites could be the cause of distant metastasis too. The ablation of remnant tissue would in all probability eliminate these theoretical risks. It may be noted that all these are unproven contentious issues except postablation serum Tg estimation that could be a good tumor marker for detecting early biochemical recurrence in long-term follow-up strategy. Radioactive iodine is administered as a form of "adjuvant therapy" for remnant ablation. There have been several reports with regard to the administered dose for remnant ablation. The first report of a prospective randomized clinical trial was published from India by a prospective randomized study conducted at the All India Institute of Medical Sciences, New Delhi in the year 1996. The study reported that increasing the empirical (131)I initial dose to more than 50 mCi results in plateauing of the dose-response curve and thus, conventional high-dose remnant ablation needs critical evaluation. Recently, two important studies were published: One from French group and the other from UK on a similar line. Interestingly, all three studies conducted in three different geographical regions of the world showed exactly similar conclusion. The new era of low-dose remnant ablation has taken a firm scientific footing across the continents.

Spontaneous pneumomediastinum: A complication of swine flu.

The occurrence of spontaneous pneumomediastinum in swine flu, or H1N1 influenza A infection, is a rare phenomenon and only few cases have been reported in children. We describe a case of spontaneous pneumomediastinum in adult infected with swine flu.

Potential requirement of positron emission tomography apparatuses in Asia and latin america including Mexico.

The number of positron emission tomography (PET) machines has been increasing in regions of East-, Southeast-, and South-Asia as well as in Latin America including Mexico. This study was performed to assess the potential requirement of PET machines in 19 countries which already use PET in the aforementioned regions. Data on the number of PET machines and internationally available characteristics of the restrictive countries such as the land area, the total population, the gross national income (GNI), and the average life span of inhabitants were obtained from IAEA, UN, WB, and WHO. Correlation between the number of PET machines and the characteristics of each country was evaluated. The potentially required number of PET machines, which was obtained by adjusting the number of PET machines with statistically significant, correlative characteristics of each country, standardized on the state of Japan, were compared. The number of PET machines could be significantly correlated to the GNI of a country and the average life span of its inhabitants (P < 0.05). Based on Japan, most of the countries in the regions would require considerably more PET machines. With installation of the potentially required number of PET machines in each of the countries, the number of PET machine per 10(6) population would increase by 1.1- to 12-fold, in comparison with the current situation. With regards to the potentially required number of PET machines, most of the countries in these regions may require a considerable increase of PET machines. Nevertheless, some countries in the Asia seem to require outside assistance such as international support in order to introduce PET and enhance the efficacy of their health services.

Incidental detection of clinically nondiagnosed inguinal hernia in (131)I whole-body scan.

I whole-body bone scan was performed for an adult male patient after postradioactive iodine ablation of thyroid carcinoma. Besides the small thyroid remnants in the neck region, an incidental detection of left inguinal hernia was made in the scan, which was later confirmed by clinical examination. Despite the large size of the hernia, the patient was unaware of the condition. It can be concluded that, similar to other imaging procedures, incidental detection of unrelated clinical problems is possible in I scan also, and such early diagnosis prevents further complications that the patient may develop in the future.

Controversies about radioactive iodine-131 remnant ablation in low risk thyroid cancers: are we near a consensus?

Well differentiated thyroid cancers (WDTC), including papillary (80%) and follicular (10%) types, are the most common endocrine cancers globally. Over the last few decades most the diagnosed cases have fallen into low risk categories. Radioactive iodine-131 (RAI) has an established role in reducing recurrence and improving the survival in high risk patients. In patients with primary tumor size <1 cm, RAI is not recommended by many thyroid societies. However, low risk WDTC has been an arena of major controversies, most importantly the role and dose of adjuvant RAI for remnant ablation to minimize chances of recurrence and improving survival. This review is an attempt to update readers about the previous and existing practice based on results of non- randomized trials and evolving trends fueled by recently published randomized studies.

Extraosseous uptake of technetium-99m methylene diphosphonate by an acute territorial cerebral infarct in a classical biodistribution pattern.

Technetium-99m methylene diphosphonate scintigraphy is usually performed to assess bone lesions, especially skeletal metastases in patients with a history of malignancy. However, it is important to recognize some specific conditions with a unique pattern of tracer uptake, especially in extraosseous locations as they are not related to primary neoplasm or metastases. Diagnosing such unusual presentation is essential as it significantly influences the clinical management. This case report describes an unusual presentation detected in a bone scan of an elderly female patient, who was a treated case of breast cancer and was referred for a bone scan to rule out bone metastases. Incidentally, a large acute territorial cerebral infarct was diagnosed, which was later confirmed by magnetic resonance imaging on diffusion-weighted images. Diagnosis of the typical presentation and timely management saved the patient life.

Unusual presentation of extraosseous metastases on bone scintigraphy.

Osteosarcoma metastases frequently occur in the lungs or the skeleton. Bone scans play an important role in disease staging by identifying other skip areas of skeletal involvement as well as extraosseous metastases. We report a case of aggressive osteosarcoma, with bone metastases and extraosseous areas of involvement in the lungs, distant lymph nodes, and peritoneal and subcutaneous metastasis seen in a preoperative Tc-99m methylene diphosphonate bone scan. These findings were confirmed with histology and correlative cross-sectional imaging.

Pancreatic metastasis detected by F-18 FDG PET/CT in a patient with breast cancer.

Pancreatic involvement by metastasis from other primaries is rare and accounts for approximately 2% to 4% of pancreatic tumors. In this article, we describe FDG-avid pancreatic involvement in a patient with diagnosis of breast cancer. We conclude that FDG PET can be a convenient noninvasive method of early detection of recurrence and in monitoring metastatic disease during follow-up in such patients. A positive FDG PET warrants histopathologic correlation for appropriate treatment.

Fluorine-18-fluorodeoxyglucose PET/CT for the evaluation of suspected recurrent uterine leiomyosarcomas.

BACKGROUND: Uterine leiomyosarcomas are rare and aggressive malignancies of the uterine corpus with high recurrence rates and poor prognoses. The current recommendation for detection of recurrent uterine leiomyosarcoma involves periodic physical examination and conventional imaging such as CT or MRI. The role of fluorine-18-fluorodeoxyglucose positron emission tomography with integrated computed tomography (FDG-PET/CT) in the detection of recurrent uterine leiomyosarcomas is not yet established. PURPOSE: To evaluate the use of FDG-PET/CT as a single integrated modality for the evaluation of suspected recurrent uterine leiomyosarcomas. MATERIAL AND METHODS: A retrospective study was performed on patients who underwent FDG-PET/CT scans for suspected recurrent uterine leiomyosarcoma. Only patients with follow-up data were included in the study. FDG-PET/CT was evaluated as a single integrated imaging modality. A positive lesion on FDG-PET/CT was defined as a focal abnormality detected on either the PET or CT components, or both. RESULTS: Sixteen consecutive patients over 5 years underwent FDG-PET/CT for suspected recurrent uterine leiomyosarcoma. Five patients were excluded due to incomplete follow-up data. The remaining 11 patients were aged 36-58 years (mean age 48). FDG-PET/CT had a sensitivity of 100% (95% CI 63-100) and specificity of 100% (95% CI 20-100) for the detection of recurrent uterine leiomyosarcomas. Sites of metastases include lungs, peritoneum, liver, pancreas and breast, of which lungs and peritoneum were the most common. Two (18%) patients had discordant findings: FDG-PET negative metastatic nodules in the breast and lung detected on the CT component. The maximum standardized uptake value (SUVmax) of metastatic lesions ranged from 2.0 to 16.0 (mean 7.6). CONCLUSION: FDG-PET/CT as a single integrated modality may be a useful for the evaluation of suspected recurrent uterine leiomyosarcomas. FDG-PET negative discordant nodules detected on the CT component may represent metastases and should be followed up closely.

Differentiating suspected nasopharyngeal infection from carcinoma using dual-tracer and multiple time-point technetium-99m sestamibi and white blood cell SPECT/CT imaging.

The role of molecular and functional imaging lies in its capability to more accurately define and characterize pathologies, with a host of varied radiotracers and techniques being available to the clinician for use. We present a case in which dual-tracer and multiple time-point single photon emission computed tomography/computed tomography imaging using technetium-99m sestamibi and white blood cell radiotracers was used to characterize an indeterminate base of skull lesion.

Intensely hypermetabolic extra-axial brainstem tumor in Erdheim-Chester disease.

Erdheim-Chester disease is a rare non-Langerhans cell histiocytosis characterized by progressive histiocytic proliferation with multiorgan involvement, typically of the kidney, skin, brain, and lung, and less frequently, the heart and retro-orbital tissue. Fluorine-18 fluorodeoxyglucose positron emission tomography (F-18 FDG PET) plays an important role in the management of this disease. It has been reported that FDG PET imaging allows accurate evaluation of the extent of the disease at baseline, as well as assessment of response to any specific therapy. In this case, a 57-year-old Chinese man presented with functional decline and a urinary tract infection. He had a prior history of xanthogranulomas of bilateral canthal masses. On imaging, he was found to have left hydronephrosis, diffuse urothelial thickening, increased density of the perinephric fat, mural thickening of the descending aorta and soft tissue masses along the posterior wall of the right atrium extending into the region of the interatrial septum and involving the right atrioventricular groove. Histopathology revealed retroperitoneal fibrosis. An IV contrast-enhanced FDG PET scan showed increased activity in a previously unidentified brain stem mass and the shafts of bilateral femora. Varying levels of FDG uptake were seen in the other lesions.