An experimental comparison of two different technetium source activities which can imitate thyroid scintigraphy in case of thyroid toxic nodule.

PURPOSE: In cases of thyroid toxic autonomous nodule, anterior projection of Tc-99m pertechnetate image shows a hot nodule that occupies most, or the entire thyroid lobe with near-total or total suppression of the contra lateral lobe. In this case is very difficult to distinguish toxic nodule from lobe agenesis. Our interest was to estimate and determinate the rate of radioactivity when the source with high activity can make total suppression of the second source with low activity in same conditions with thyroid scintigraphy procedures. MATERIAL AND METHODOLOGY: Thyroid scintigraphy was performed with Technetium 99 meta stable pertechnetate. A parallel high resolution low energy collimator was used as an energy setting of 140 KeV photo peak for T-99m. Images are acquired at 200 Kilo Counts in the anterior projection with the collimator positioned as close as the patient's extended neck (approximately in distance of 18 cm). The scintigraphy of thyroid gland was performed 15 minutes after intravenous administration of 1.5 mCi Tc-99m pertechnetate. Technetium 99 meta stable radioactive sources with different activity were used for two scintigraphies studies, performed in same thyroid scintigraphy acquisition procedures. In the first study, were compared the standard source with high activity A=11.2 mCi with sources with variable activities B=1.33 mCi; 1.03 mCi; 0.7 mCi; 0.36 mCi; and 0.16mCi) in distance of 1.5cm from each other sources, which is approximately same with distance between two thyroid lobes. In the second study were compared the sources with low activity in proportion 70:1(source A = 1.5 mCi and source B=0.021mCi). As clinical studies we preferred two different patents with different thyroid disorders. There were one patient with thyroid toxic nodule in the right lobe, therefore the second patient was with left thyroid nodule agenesis. RESULTS: During our examination, we accurately determined that two radioactive sources in proportion 70:1 will be displayed as only one source with complete suppression of other source with low radioactivity. Also we found that covering of toxic nodules with lead cover (plaque), can allow visualization of activity in suppressed lobe. CONCLUSION: Our study concluded that total lobe suppression, in cases of patients with thyroid toxic nodule, will happened for sure, if toxic nodule had accumulated seventy times more radioactivity than normal lobe. Also we concluded that covering of the toxic nodule with lead plaque, may permit the presentation of radioactivity in suppressed nodule.

Abnormal insertion of right ureter into the left ureter associated with absence of normal right ureterovesical junction.

AIM: There are lots of factors which cause the dilatation of one or both ureteres. Congenital absence of ureterovesical junction was reported as very rare cause of megaureter. Early detection of congenital absence of normal ureterovesical junction offers utilities for reconstruction and prevents the complications such as megaureter and vesicoureteral reflux. MATERIAL AND METHODS: A male patient 16 months old was referred for renal DTPA scintigraphy confirmed previously with diagnosis as megaureter of left kidney associated with consecutive stasis grades III of the left ureter. Dynamic renal scintigraphy was performed after intravenously injection of 37 MBq Tc DTPA. Scintigraphy was carried out on a Dual Head-Siemens gamma camera using a high resolution collimator. During the dynamic scintigraphy patient was positioned in supine position. RESULTS: Male patient 16 month old with vomiting, diarrhoea, fever, indolence during last two weeks were referred for dynamic renal scintigraphy. Meanwhile patient was also performed other laboratory tests such as: RBC = 4.07 x 1012, SRE= 47, Hb = 111, Bun = 5.2, Creatinine=29 and urine proteins ++. Examinations with Ultrasound, CXR and intravenously urography confirmed diagnosis of left megaureter associated with consecutive stasis Gr.III and Stasis of left kidney gr. I-II. With dynamic scintigraphy was confirmed the absence of right ureterovesical junction followed by joining of right and left ureter at the level of the lower part of the left ureter. CONCLUSION: Renal dynamic scintigraphy demonstrates abnormal insertion of right ureter into the left ureter associated with absence of normal right ureterovesical junction, right megaureter and with vesicoureteral reflux.

Report of one interesting case--unilateral kidney agenesis associated with ipsilateral kidney malrotation, anal atresia and pulmonary artery failure.

AIM: Renal agenesis is a fairly common congenital anomaly with an unknown definite etiology. Unilateral renal agenesis is much more common than bilateral renal agenesis, but it usually does not carry any major health consequence, as long as the other kidney is healthy. In some cases, renal agenesis may by associated with other congenital anomalies. We report a neonatal female patient born with unilateral renal agenesis associated with malrotation of ipsilateral kidney, anal atresia and pulmonary artery failure. MATERIAL AND METHODS: One month old female child was referred to Nuclear Medicine Department for dynamic renal scintigraphy which performed after intravenously injection of 0.5 mCi(99m) TcDTPA. Scintigraphy was carried out on a Dual Head-Siemens gamma camera using a high resolution collimator. During the dynamic scintigraphy patient was positioned in a supine position. Furosemide, as diuretic stimulator was administered intravenously at 18th minute of the study. RESULTS: The female patient, eight months old, with cough, short breath (dispnea), fatigue, nausea, vomiting and diarrhea was referred to DTPA renal scintigraphy. Symptoms were manifested ten days before patient had undergone the renal scintigraphy. During this time the patient was under pediatrics' control. A patient has undergone the biochemistry, ultrasound and radiologic examinations. Samples were isolated from the urine culture Pseudomonas aureginosa. The patient received antibiotics (Amikacin) for seven days, whereas last five days she received salbutamole and bisolvon. During physical examination we noticed a left abdominal stoma without palpation sensibility associated with an imperforate anus. From DTPA renal scintigraphy we found the absence of a right kidney, malrotation of a left kidney associated with seriously problems during the elimination of urine. DISCUSSION: Unilateral renal agenesis usually is without any major health consequences, but in cases where it is associated with other congenital malformations, such as malrotation of existing kidney, anal atresia and cardiopulmonary anomalies can be very serious problem for life. CONCLUSION: Dynamic renal scintigraphy is very highly sensitive and helpful method for detection of renal congenital malformations and function abnormalities.