Scintigraphic diagnosis of a right to left shunt in end-stage lung disease.

PURPOSE: The presence of a right to left shunt influences the surgical approach to lung transplantation in patients with end-stage pulmonary disease. The purposes of this study included comparing contemporaneous lung scintigraphy with cardiac catheterization in the detection of intracardiac shunts in patients with end-stage lung disease and the point prevalence of right to left shunting was determined in patients with several different types of end-stage lung disease. METHODS: Hundred and twenty six patients with end-stage lung disease who were candidates for lung transplantation underwent perfusion images of the lungs with Tc-99m-labeled macro-aggregated albumin (MAA). Planar scans of the brain and the kidneys were performed contemporaneously. Statistical analyses included correlation ofthe clinical, laboratory and scintigraphic variables. Group means were compared with the students t-test (two-tailed P-value). RESULTS: There were 21 patients with primary pulmonary hypertension (PPH), 72 with emphysematous lung disease (COPD), 22 with pulmonary fibrotic disease (PF) and 11 with congenital heart disease (CHD) leading to pulmonary hypertension. Only 13 patients (10.3%) were found to have a right to left shunt. Of these, 4 had PPH, 2 had PF, and 7 had CHD. No shunts were found in patients with emphysema. All the positive studies had abnormally increased activity in both the brain and the kidneys. However, there were 25 cases with renal activity and none of these patients had brain activity or clinical evidence of a shunt. Increased pulmonary artery pressure was associated with scintigraphic presence of a shunt. There were no cases of a right to left shunt with a mean pulmonary artery pressure less than 50 mm Hg. In the subset of patients with a pulmonary pressure greater than 50 mm Hg, approximately 40% of the patients had a right to a left shunt. There were no measurable differences in the spirometry results, right ventricular ejection fraction (RVEF) or left ventricular ejection fraction (LVEF) in the subgroup of patients with PPH and right to left shunt in comparison with patients with PPH but without a right to left shunt. CONCLUSIONS: The findings indicate that images of the brain, but not the kidneys, are an effective way to diagnose extrapulmonary right to left shunts in patients with end-stage pulmonary disease. The problem of a right to left shunt is uncommon in patients with emphysematous lung disease and relatively common in patients with primary pulmonary hypertension.

Tc-99m dextran scintigraphy in the diagnosis of protein losing enteropathy.

Tc-99m dextran scintigraphy was performed on a 16-year-old male patient with protein losing enteropathy. Abnormal leakage of the radiotracer was observed in the right upper lumbar area that moved over time and excreted in the stool which was suggestive of protein loss. It is concluded that Tc-99m dextran is useful in the detection of protein losing enteropathy which is not detected by extensive radiological and endoscopic examination.

Superiority of tc-99m MAG3 to tc-99m DTPA in treating a patient with mild renal artery stenosis.

A 22-year-old female patient with severe hypertension underwent both Technetium-99m diethylenetriaminepentaacetate and Technetium-99m mercaptoacetyltriglycine basal and captopril renal scintigraphy. While no significant change was seen with Tc-99m DTPA, there was left sided parenchymal retention of captopril Tc-99m MAG3 suggesting renal artery stenosis which was confirmed by angiography.

Neonatal hypothyroid disease: absent salivary gland evident on technetium-99m pertechnetate scan.

PURPOSE: Technetium-99m pertechnetate scintigraphy is a well-established technique for diagnosing congenital hypothyroid disease. However, the biodistribution of pertechnetate (TcO4-) in neonates and young infants is not well documented. The purpose of this study was to analyze and document the biodistribution of TcO4- in young infants. MATERIALS AND METHODS: Scintigraphic studies of 31 patients being examined for hypothyroid disease were analyzed. All patients had elevated levels of thyroid-stimulating hormone. Dyshormonogenesis was diagnosed in 7 patients, ectopic thyroid glands in 19, and agenesis in 5. RESULTS: Images of the neck, chest, and abdomen taken in the anterior and left lateral positions using a low-energy, all-purpose collimator were reviewed. Twenty-six of the patients had no accumulation of the isotope in the salivary glands and 11 had no gastric uptake on either view. CONCLUSIONS: Based on the absence of salivary gland activity in the patients examined, this study suggests that this is a normal finding in infants younger than 3 months. A lateral view of the neck with markers is sufficient to localize the thyroid gland, because any activity in the neck region would belong to the thyroid. Furthermore, poor and variable uptake of the isotope in the stomach may lead to false-negative results, so caution is urged in the use of this tracer in Meckel's scintigraphy in young infants, particularly if the study findings are within normal limits.

Scintigraphic imaging of uveal melanoma with 99Tcm-glutathione.

A prospective study with a new tumour-seeking agent, 99Tcm-glutathione (GSH), was performed on 17 patients with choroidal melanoma. Planar and SPECT images using 99Tcm-GSH clearly demonstrated melanotic melanoma but failed to show amelonotic melanomas. Following confirmation of our results by concurrent ultrasonography and magnetic resonance imaging or computed tomography, patients were managed by either 125I plaque brachytherapy, diode laser transpupillary thermotherapy or enucleation depending on the site and location. In combination with other diagnostic tests, 99Tcm-GSH scintigraphy may play a role in the detection of uveal melanoma and its possible distant metastases.

Correlation of flow cytometric parameters and transferrin receptors with gallium-67 scintigraphic images in lymphoma patients.

The purpose of this study was to determine the correlation of flow cytometric parameters and transferrin receptors with gallium-67 scintigraphic imaging results in Hodgkin's and non-Hodgkin's lymphoma patients. DNA content and cell cycle analyses were performed using flow cytometry and transferrin receptor analysis was carried out by the immunohistochemistry technique in 24 patients aged between 16 and 62 years. All patients underwent gallium-67 scintigraphy, and tumour to background ratios were calculated. The findings were correlated with computed tomography and/or magnetic resonance imaging. A strong relationship was observed between flow cytometry and transferrin receptor expression with gallium-67 tumour scintigraphy [P = 0.005, r = 0.054 and P = 0.038, r = 0.54 (Spearman test), respectively]. The results of this study show that there is a close correlation between each of these modalities and, as they reflect the biological activity of the tumour, together they have a major role in treatment and follow-up.

Technetium-99m pertechnetate uptake in ectopic parathyroid adenoma.

A 37-year-old male with a persistent increased parathyroid hormone level, after subtotal thyroidectomy and parathyroidectomy, was referred for scintigraphic localization of a possible ectopic parathyroid adenoma. Tc-99m pertechnetate and Tc-99m MIBI scintigraphy were performed on separate days. There was marked uptake of both tracers in the mediastinum, which at surgery was confirmed to be an extrathyroidal parathyroid adenoma. Hypervascularity was suggested as a possible explanation for rare cases of pertechnetate avid parathyroid adenomas. And Tc-99m MIBI scintigraphy proved to be a successful imaging procedure for ectopic parathyroid tissue.

Technetium-99m (V) dimercaptosuccinic acid uptake by choroidal melanoma before and after iodine-125 brachytherapy.

PURPOSE: The value of the new tumour-seeking agent technetium-99m (V) dimercaptosuccinic acid (99mTc (V) DMSA), is assessed by the visualization of choroidal melanoma before and after iodine-125 episcleral plaque brachytherapy. METHODS: A prospective study was conducted on 12 consecutive patients with choroidal melanoma that was to be treated with plaque brachytherapy. The pre-operative mean (+/- SD) maximal tumour basal diameter was 12.9+/-2.9 mm and the mean tumour height was 8.2+/-2.9 mm. Each patient had planar scintigraphy and single-photon emission computed tomography using 99mTc (V) DMSA 2 days before treatment and 8 months following plaque removal. The calculated tumour to background ratios of these two tests were compared. RESULTS: The pre-operative tumour to background ratio was 1.8+/-0.4 and all tumours could be correctly identified. At the time of postoperative imaging, all melanomas showed varying degrees of regression. The mean tumour height was 4.4+/-2.1 mm. The tumour to background ratio was 1.4+/-0.3. The difference between the two scintigraphic results was statistically significant (P = 0.002). CONCLUSIONS: Technetium-99m (V) DMSA scintigraphy can accurately detect choroidal melanoma and document tumour response following episcleral radioactive plaque therapy. As such, this test can be an alternative ancillary investigative tool in the rare event of opaque media or diagnostic uncertainty.

Visualization of orbital retinoblastoma with technetium-99m (V) dimercaptosuccinic acid.

The potential contributions of technetium-99m (V) dimercaptosuccinic acid scintigraphy in the evaluation of orbital retinoblastoma, its local extensions and metastases were assessed in this study. Both planar and SPECT images clearly demonstrated the primary tumor and metastatic sites. Following confirmation of our results by contemporaneous ultrasonography, MRI and a subsequent incisional biopsy, the patient was treated with external beam radiotherapy and chemotherapy. This preliminary study showed that in combination with other diagnostic tests, Tc-99m (V) DMSA scintigraphy may play a role in the detection and follow-up of the local tumor extensions and metastases in patients with retinoblastoma.

Scintigraphic evaluation of tumors metastatic to the choroid using technetium-99m(V)-dimercaptosuccinic acid.

Technetium-99m(V)-dimercaptosuccinic acid scintigraphy was used to evaluate three patients with intraocular tumors who had metastatic breast, lung, and rectal carcinomas, respectively. At the time of initial examination, two patients had no known systemic cancer, but the scintigraphy results in one patient revealed the primary site and were highly suggestive of disseminated carcinomatosis in the other patient. In the third patient, scintigraphy was successful to confirm very small bilateral intraocular tumors and also other systemic lesions. Technetium-99m(V)-dimercaptosuccinic acid scintigraphy can be reliably employed in a very select group of patients with intraocular tumors where metastatic carcinoma is a serious diagnostic possibility against a primary intraocular malignancy. This safe and promising tumor-imaging agent has the ability to demonstrate the ocular lesions and other systemic foci simultaneously, information that would prove to be crucial in both the diagnosis and the management of the patient.

Visualization of uveal amelanotic melanoma with technetium-99m(V) dimercaptosuccinic acid.

The possibility of using technetium-99m(V) dimercaptosuccinic acid, Tc-99m DMSA, in the evaluation of uveal amelanotic melanoma was assessed in this study. Both planar and SPECT images clearly demonstrated the tumor. Following confirmation of our results by contemporaneous ultrasonography and MRI the patient was treated with Iodine-125 brachytherapy. In combination with other diagnostic tests, Tc-99m(V) DMSA scintigraphy may play a role in the detection of uveal melanoma and its possible systemic metastases.

Laurence-Moon-Biedl syndrome: scintigraphic appearance of kidneys.

We report a 7-year-old child with Laurence-Moon-Biedl syndrome, an autosomal recessive syndrome, with impaired renal function detected by means of technetium-99m diethylenetriamine-pentaacetic acid (Tc-99m DTPA), technetium-99m dimercaptosuccinic acid (Tc-99m DMSA) scintigraphy, and ultrasonography. The altered renal morphology and decreased renal functions are documented.