Biomedical subjects
Publications and source records attributed to M K Karimeddini.
An 18-year-old man with prune belly syndrome had negative renal outlines during a Tc-99m DTPA study. These areas filled with activity at 2 hours, and represented greatly dilated collecting systems.
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Tc-99m MDP injected into a central venous catheter showed a pattern corresponding to the left pleural space. The catheter had perforated into this locale.
A 75-year-old man had multiple findings that indicated thromboembolic disease. A radiocolloid study showed splenic defects. The remainder of the spleen was hot on radiogallium imaging. The patient had Trousseau's syndrome (tumor-associated thromboembolism) due to carcinoma of the pancreas. The splenic vein was obstructed. Vascular compromise should be considered in the differential diagnosis of the radiogallium hot spleen.
Radionuclide studies often define the gastric contents as a photopenic volume. In many cases, the volume can be described by a spherical approximation, which allows a first approach to calculating the volume and monitoring its change. With the further assumption that the stomach wall is a sphere surrounding the contents, the effective thickness of the gastric wall can be determined. This thickness is approximately 0.4-4 mm.
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An 11 year old girl, with biopsy proven neuroblastoma cells in the bone marrow, had lack of uptake of 99mTc-sulfur colloid in marrow of the pelvic area. Her chemotherapy was changed. A repeat image 25 days later then showed accumulation of radiocolloid in the pelvic region.
The effects of endurance training on the diastolic properties of the left ventricle were examined by comparing left ventricular filling rates in 11 male distance runners and 12 age-matched nonathletic control subjects selected to have nearly similar heart rates at rest. Maximal oxygen consumption was 69 +/- 11 ml/kg-min for the athletes and 48 +/- 8 ml/kg X min for the control subjects (p less than 0.001). Left ventricular end-diastolic dimension, posterior wall thickness and mass were determined by echocardiography, and average left ventricular filling rate was determined with a nonimaging scintillation probe. Electrocardiographic voltage was significantly greater in the athlete group than in the control group (sums of the voltages of the S wave in lead V1 and the R wave in lead V5 were 40 +/- 10 and 26 +/- 7 mV, respectively) (p less than 0.001), whereas ejection fraction was similar in the two groups. Despite a modest degree of left ventricular hypertrophy in the athlete group compared with the control group (left ventricular mass index 127 +/- 30 and 82 +/- 13 g/m2, respectively) (p less than 0.001), the average left ventricular filling rate was similar in the two groups (2.53 +/- 0.34 versus 2.38 +/- 0.29 end-diastolic counts/s, p = NS). There was no trend for the athletes with a higher left ventricular mass to exhibit a slower filling rate. These findings demonstrate that unlike pathologic hypertrophy associated with chronic hemodynamic over-loading, physiologic left ventricular hypertrophy is not accompanied by slowed left ventricular diastolic filling.
To define the extent of left ventricular ejection and filling abnormalities in patients with mild hypertension, a non-imaging nuclear probe was used to generate high resolution time-activity curves in 25 patients with an average systolic blood pressure of 154 +/- 20 mm Hg and diastolic pressure of 98 +/- 8 mm Hg. The hypertensive patients did not meet electrocardiographic criteria for left ventricular hypertrophy, and none had evidence of ischemic or other cardiac disease. Compared with 25 age-matched normal subjects who had average systolic and diastolic pressures of 123 +/- 10 and 79 +/- 8 mm Hg, respectively, the hypertensive patients had a significantly lower ejection rate (2.00 +/- 0.20 versus 2.34 +/- 0.36 end-diastolic counts/s for the control group, p less than 0.05) and ejection fraction (58 +/- 4.9 versus 62 +/- 4.4) (p less than 0.05). The hypertensive patients had a markedly lower average rapid left ventricular filling rate (1.87 +/- 0.32 versus 2.69 +/- 0.41 counts/s for the control group, p less than 0.001). Although there was a modest inverse relation between echocardiographic left ventricular mass index and filling rate in the hypertensive patients (r = -0.59, p less than 0.01), 4 of 12 hypertensive patients with normal left ventricular mass index had a depressed filling rate. All of the hypertensive patients with increased left ventricular mass index had an abnormal left ventricular filling rate (less than 1.89 end-diastolic counts/s).(ABSTRACT TRUNCATED AT 250 WORDS)
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The kidneys were evaluated on [99mTc]phosphonate bone scans using 35 studies from 23 individuals with multiple myeloma; these images were compared with those from 50 controls. In each case, the kidneys could be visualized and calculation was made of the renal:skeleton ratio. Two myeloma patients showed an elevated renal:skeleton ratio. One was due to reduced vertebral uptake of [99mTc]phosphonate following therapeutic radiation. In the second case, the elevated ratio was related to renal uptake of the tracer (independent of urinary retention), and was consistent with nephrocalcinosis. No significant correlation between the renal:skeleton ratio and the degree of hypercalcemia, proteinuria, or renal impairment was found. We conclude that bone scintigraphy represents a safe, simple means of demonstrating renal presence and activity in multiple myeloma patients. However, calculation of the renal:skeleton ratio is not directly helpful in clarifying the events of calcium metabolism.
Oligohydramnios can be associated with fetal renal abnormalities. A pregnancy marked by oligohydramnios produced a male child with the facial features of Potter's syndrome. Kidneys could not be demonstrated by ultrasound or by a 99mTc -DTPA dynamic study. A potential role for renal scintigraphic techniques, in an effort to define kidneys in such cases, was discussed.
A 77-year-old man with a stent in place for biliary drainage was examined. Intravenously administered 99mTc-diisopropyl-IDA showed little accumulation of activity in the abdomen while the stent was draining internally. Upon switching the stent to external drainage, it was possible to monitor the slow movement of the bile which contained radioactivity. Imaging over the liver and comparing activity changes with a 99mTc standard showed that the decrease in hepatic radioactivity was identical to that occurring in the 99mTc standard. The liver was thus in a "steady state" for excretion of the 99mTc hepatobiliary agent, for it was extracting as much radioactivity from the circulation as it was excreting.
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A case is presented in which intravenous administration of glucagon, presumably by relaxation of the sphincter of Oddi, facilitated the transit of a hepatobiliary radiopharmaceutical from the gallbladder into the bowel. This approach is likely more feasible than food intake and at least theoretically safer than cholecystokinin administration. Further studies are needed to assess the actual usefulness of this intervention.