Role of exercise tolerance test (ETT) and gated single photon emission computed tomography-myocardial perfusion imaging (SPECT-MPI) in predicting severity of ischemia in patients with chest pain.

This was an observational study carried out in the department of cardiology. Bangabandhu Shikh Mujib Medical University (BSMMU), Dhaka in collaboration with Institute of Nuclear Medicine (INM), Shabag, Dhaka during the period October 2002-March 2003. A total of 54 patients presenting with Canadian Cardiovascular Society (CCS) class I-II severity of chest pain with mean +/-SD age 49.88 +/- 8.44 yrs and having male to female ratio 5.75:1 were included in the study. The main objective of the study was to predict severity of myocardial ischemia by Exercise Tolerance Test (ETT) determined by Duke Treadmill Score (DTS) and by perfusion pattern observed following Single-Photon Emission Computed Tomography myocardial perfusion imaging (SPECT-MPI). All patients underwent ETT and then SPECT-MPI scan using Tc-99m-tetrofosmin in one-day stress and rest protocol. Coronary angiogram (CAG) was done with in six months of the perfusion study. After performing ETT, patients were categorized by DTS and myocardial perfusion studies were also stratified according to severity of perfusion defect. The formula used to calculate the score was: Exercise time- (5 x ST segment deviation)-(4 X Treadmill angina index). The angiographic findings (significant >50% stenosis) and perfusion defects in MPI were compared with the severity of DTS. There were 31 patients who had CAG proven (>50% luminal diameter narrowing) CAD and 23 patients free of CAD. After ETT patients were categorized by Duke Treadmill Score into high DTS 12 (22.22%) patients, intermediate DTS 20 (37.03%) patients low DTS 22 (40.74%) patients. In high DTS group 91.66% patients had perfusion defect, whereas in intermediate and low risk group it was 60% and 40.9% respectively. In high DTS group 91.66% of patients had angiographicaly proven CAD, 58.33% of them had triple vessel disease (TVD) while in intermediate and low risk groups angiographically proven CAD were 65% and 22.72% of whom TVD only in 15% & 0% respectively. The results of ETT using DTS score were satisfactorily correlated with SPECT-MPI scanning in high DTS subsets of patients only. It is therefore, suggested that patient of high risk DTS do not need for myocardial perfusion imaging study and should undergo CAG for further evaluation. But the intermediate and low risk groups were needed myocardial perfusion imaging study to guide for further evaluation.

Lymphoscintigraphy in staging and management of breast cancer.

Internal mammary lymphoscintigraphy (IML) is a simple non-invasive and reproducible technique to determine the extent of the parasternal node invasion in patients suffering from breast cancer. A total forty four patients--37 before surgery or any sort of treatment and seven patients after having undergone surgery, chemotherapy and/or radiotherapy were included in this study to assess the potential role of lymphoscintigraphy in the context of the present 'state of the art' of staging and management of breast cancer patients in Bangladesh. The scintigraphic test was done using Technetium 99m (Tc-99m) Antimony sulfide colloid in a dose of 500 microCi injected interstitially into the sub-costal space. Images were obtained after two to three hours on a Gamma Camera and the study findings were then interpreted as normal, abnormal and equivocal. The scintigraphic images obtained in patients who had undergone surgery, chemotherapy and/or radiotherapy were difficult and more challenging to interpret than those images obtained from patients before surgery or other therapy. This was evidenced by the high number (71%) equivocal cases of IML findings in patients after treatment as compared to only 22% equivocal cases in patients studied before surgery or other therapy. Parasternal lymph node involvement was found to occur regardless of the site or size of the primary tumour. Thirty three percent of tumours located in the outer quadrant showed abnormal nodes on IML. When the size was considered, IML was found abnormal in 22.20% patients with tumour size less than 2 cm in diameter. Correlation of IML with clinically palpable lymph nodes showed abnormal scan findings in 18% patients without clinically demonstrable axillary lymph nodes. These findings are in agreement with previously published data and suggests that conventionally classified stage I patients may in effect be in stage II or even in stage III of the disease. In conclusion, when the technique of lymphoscintigraphy is done with a comprehensive overview of the patient, and when the interstitial injection site is correct, it will generally lead to a logical and clinically useful interpretation of the data for more efficient management of the patient with breast cancer.

Role of radioiodine in management of thyroid cancer: experience with 70 cases.

Results of 70 cases of differentiated thyroid carcinoma managed with I131 and surgery have been reported. These results add to the body of knowledge that already exists in the field of treatment of thyroid cancer with radioactive iodine. These results also indicate that the success of radioiodine therapy depends on adequate surgical removal of the thyroid tissue.