Ectopic thyroid tissue on thallium/technetium parathyroid scan.

The thallium 201/technetium 99m pertechnetate radionuclide study is becoming widely accepted as a means of localizing abnormal or aberrantly located parathyroid tissue. We describe a case in which ectopic retrosternal thyroid tissue appeared as a parathyroid adenoma on thallium-201/technetium-99m pertechnetate scan. Physicians who use this radionuclide study should be aware of the possibility of false-positive images within the mediastinum.

Hypoglycemia in pregnancy. Occurrence due to adrenocorticotropic hormone and growth hormone deficiency.

Severe symptomatic hypoglycemia (serum glucose level, 24 mg/dL) developed in a 23-year-old, 147.3-cm-tall woman during her late second and third trimesters of pregnancy. Endocrine studies disclosed insulin levels less than 2 microU/mL; growth hormone level less than 3 ng/mL; and cortisol level less than 1 microgram/dL. Hydrocortisone therapy corrected her hypoglycemia, and she was delivered of a healthy female infant. Postpartum, her evaluation included normal thyroid function studies, a normal thyroid-stimulating hormone response to protirelin (thyrotropin-releasing hormone), normal serum and urine gonadotropin levels, normal serum prolactin, normal sella turcica tomograms, and a normal EMI brain scan. Urine 17-hydroxycorticosteroids increased during a four-day cosyntropin infusion, but failed to rise after metyrapone administration. The growth hormone level failed to rise after stimulation with levodopa and propranolol administration. The patient was believed to have idiopathic partial hypopituitarism, with hypoglycemia being due to adrenocorticotropic hormone (ACTH) and growth hormone deficiency and the drain of maternal glucose by the fetus. It is suggested that pregnant women with symptomatic hypoglycemia be treated with glucocorticoids while awaiting the results of their endocrine evaluation.

Reduced bone mineral content in totally thyroidectomized patients: possible effect of calcitonin deficiency.

To further investigate the relationship between calcitonin deficiency and osteoporosis, we have measured bone mineral content (BMC) by single photon absorptiometry in patients made iatrogenically calcitonin deficient by prior total thyroidectomy for thyroid cancer. Compared to sex-, age-, height-, and weight-matched normal controls, male patients had a significantly lower mean BMC at the midradius (1.162 +/- 0.02 vs. 1.301 +/- 0.05 g/cm; P less than 0.02) and the distal radius (1.180 +/- 0.04 vs. 1.338 +/- 0.04 g/cm; P less than 0.01). Female patients also had a significantly lower BMC at the midradius compared to those of a similarly matched group of normal controls and a group of patients on L-T4 suppression for nodular goiters (0.791 +/- 0.04 vs. 0.896 +/- 0.05 vs. 0.891 +/- 0.03 g/cm; P less than 0.025). We conclude that calcitonin deficiency from surgical thyroidectomy is associated with significant decreases in bone mineral content in both sexes. This lends further support to the concept that calcitonin deficiency may be an important causative factor in the development of osteoporosis.

Human breast milk excretion of iodine-131 following diagnostic and therapeutic administration to a lactating patient with Graves' disease.

Previous reports on the excretion of 131I into human breast milk have recommended discontinuance of breast feeding from 1 to 12 days following diagnostic tracer doses of 131I. Recent excretion models have calculated that breast feeding could safely resume 56 days following a 5 microCi (0.185 MBq) 131I maternal tracer dose. We studied a postpartum patient with Graves' disease following first an uptake dose of 8.6 microCi (0.317 MBq) and then for 38 days following a 9.6 mCi (355 MBq) therapy dose of Na131I. We calculated from our data that although nursing could not be safely resumed for 46 days following the 8.6-microCi uptake dose, nursing could resume in this patient 8 days after a 100-nCi (3.7 KBq) dose. Extrapolating this data to impure 123I (p, 2n or p, 5n) we feel that standard 100-microCi (3.7 MBq) doses of either 123I preparation is not suitable if nursing is to be resumed.

Stimulated salivary clearance of technetium-99m pertechnetate.

A method to determine stimulated salivary clearance of pertechnetate is presented. It is easy to perform and separates normal patients (range 15.0 to 40.3 ml/min) from patients with known salivary disorders (range 1.2 to 10.6 ml/min).

Methods for measuring GFR with technetium-99m-DTPA: an analysis of several common methods.

Several commonly used scintigraphic methods of GFR measurement were evaluated. Forty-three adult patients with a wide range of ages and renal function were studied. The two-sample plasma method of Russell and the urinary method of Jackson were the most accurate methods overall. The one-sample plasma method of Russell, the volume of distribution method of Fawdry, and a terminal slope method were less reliable, especially at low (0-60 ml/min) GFRs. The renal uptake method of Gates correlated poorly to the standards at all GFR levels even when corrected for body surface area or blood volume. The Russell two point and Jackson urinary GFR's can be used as complementary techniques and are recommended as primary methods of scintigraphic GFR determination.

Lymphocele: the spectrum of scintigraphic findings in lymphoceles associated with renal transplant.

Lymphocele is a well recognized complication of renal transplant surgery. We performed a retrospective review of 305 renal transplant patients with over 2,500 scintigraphic exams to describe the pattern of activity on technetium-99m-DTPA blood flow and dynamic imaging, and iodine-131-OIH studies. Diagnostic criteria for a lymphocele were ultrasonic evidence of a perirenal fluid collection and analysis of that fluid that demonstrated BUN, creatinine, and electrolytes similar to the patient's plasma. Scintigraphic findings were attributed to a lymphocele if abnormalities were in the same area as the ultrasound fluid collection. Scintigraphic findings attributable to lymphocele resolved in all patients following surgical drainage or peritoneal window placement. Six of the 11 documented lymphoceles demonstrated a cold defect on initial dynamic images that "filled in" to equal background activity and another exceeded background. Three cases showed a rim of increased activity surrounding the lymphocele ("rim sign").

Isolation of glycosaminoglycans from basement membranes of brain microvessels.

Although the core protein of a heparan sulfate proteoglycan has been detected in brain microvessel basement membranes by immunoperoxidase staining, cytochemical evidence of a glycosaminoglycan component, in the form of discrete staining with ruthenium red, is not found. To resolve this discrepancy, we examined the glycosaminoglycan content of this basement membrane directly. Microvessels were isolated from pig cerebral cortex, and basement membranes freed from cellular elements. Following digestion with papain and Pronase, the glycosaminoglycans were precipitated with cetyl pyridinium chloride and ethanol. The resulting extract contained uronic acid, and after electrophoresis on Super Sepraphore revealed 2 bands: One co-migrated with heparan sulfate standard, the other with chondroitin sulfate A and C. The first was completely eliminated by nitrous acid and heparitinase, but not by hyaluronidase or chondroitinase ABC and was therefore confirmed as heparan sulfate; the other band was eliminated by chondroitinase ABC but not by the other three treatments. The findings suggest that basement membrane of brain microvessels, like other vascular basement membranes, contains heparan sulfate and chondroitin sulfate A and/or C. The failure of staining with ruthenium red is probably a result of unique structural features of this basement membrane, rather than an absence of glycosaminoglycan.

Bone mineral content and menstrual regularity in female runners.

The relationship between bone mineral content and menstrual regularity in 10 amenorrheic runners (0-3 menses during the past year), 12 runners with regular menstrual cycles (10-12 menses during the past year), and 15 non-athletic women with regular menstrual cycles was investigated. Comparisons of the two groups of runners indicated no significant differences in body fatness, average weekly running distance, or average daily intake of calcium (Ca), phosphorus (P), and Ca/P ratios. Mean bone mineral content for the three groups, measured by photon absorptiometry, was 0.508, 0.529, and 0.544 g X cm-2, respectively, at 3 cm distal radius, and 0.707, 0.700, and 0.707 g X cm-2, respectively, at one-third distal radius, indicating no significant differences among the groups (P less than 0.05). However, a significant relationship (r = 0.77) was noted between bone mineral content and body fatness only in the amenorrheic runners. Within the amenorrheic population, the five thinnest runners had significantly lower mean bone mineral content values at 3 cm distal radius (0.457 g X cm-2) than the five runners with higher relative body fatness (0.559 g X cm-2). We conclude, therefore, that amenorrhea, independent of body composition, was not related to reduced bone mineral content in female runners. However, the combination of excessive thinness and amenorrhea may, in fact, predispose female athletes to reduced bone mass.

Gallium-67 uptake by the thyroid associated with progressive systemic sclerosis.

Although thyroidal uptake of gallium-67 has been described in several thyroid disorders, gallium-67 scanning is not commonly used in the evaluation of thyroid disease. Thyroidal gallium-67 uptake has been reported to occur frequently with subacute thyroiditis, anaplastic thyroid carcinoma, and thyroid lymphoma, and occasionally with Hashimoto's thyroiditis and follicular thyroid carcinoma. A patient is described with progressive systemic sclerosis who, while being scanned for possible active pulmonary involvement, was found incidentally to have abnormal gallium-67 uptake only in the thyroid gland. Fine needle aspiration cytology of the thyroid revealed Hashimoto's thyroiditis. Although Hashimoto's thyroiditis occurs with increased frequency in patients with progressive systemic sclerosis, thyroidal uptake of gallium-67 associated with progressive systemic sclerosis has not, to our knowledge, been previously described. Since aggressive thyroid malignancies frequently are imaged by gallium-67 scintigraphy, fine needle aspiration cytology of the thyroid often is essential in the evaluation of thyroidal gallium-67 uptake.

Failure of washout following gustatory stimulation in Warthin's tumour.

Scintigraphically, Warthin's tumour usually demonstrates increased tracer uptake compared to normal adjacent salivary tissue. A case is presented in which tumour uptake is no greater than the normal adjacent gland. Gustatory stimulation results in failure of tumour tracer washout, and this finding rather than 'hot' salivary mass is the sine qua non of the scintigraphic diagnosis of Warthin's tumour.

Radionuclide demonstration of a renopleural fistula following trauma.

A renopleural fistula was detected on a Tc-99m DTPA renal study during evaluation for possible post-traumatic urinoma.

Masked obstruction of the renal collecting system.

Two cases of apparent unilateral renal obstruction in which lesser contralateral obstructions were not seen are presented. In both cases, relief of the more severe obstruction resulted in an unmasking of the milder contralateral lesion.

Parathyroid subtraction imaging--pitfalls in diagnosis.

Since 1985 when parathyroid subtraction scintigraphy was presented in atlas form in this journal, the T1-201-Tc-99m computer subtraction studies have become more and more popular. Although the study has been quite accurate in localizing abnormal parathyroid pathology, the rate of false positive studies has been somewhat excessive, usually due to thyroid pathology. This atlas is an update of that previous work with the goal of presenting a scheme of interpretation that lessens the incidence of false positive studies as well as presenting many of the pitfalls in diagnosis of parathyroid disease.

Duodenogastroesophageal reflux. Demonstration with Tc-99m DISIDA imaging.

Duodenogastroesophageal reflux is demonstrated using cholescintigraphy in a patient with severe esophagitis.

Differential diagnosis of prolonged cortical retention of radiotracer in technetium-99m DTPA renal scintigraphy.

The mechanisms of prolonged renal cortical tracer retention in Tc-99m DTPA scintigraphy are discussed and a variety of examples are presented.

Hyperalimented lung diagnosed by perfusion scan.

Injection of radiopharmaceutical through a catheter may be useful in localizing its placement. A case is described in which a central venous line had punctured to superior vena cava, delivering hyperalimentation solution into the right pleural space.

Diffuse radioiodine lung uptake in miliary thyroid carcinoma metastases.

A diffuse pattern of homogeneous tracer uptake is seen by I-131 scintigraphy in a patient with widespread miliary lung metastases due to papillary thyroid carcinoma. This case report emphasizes the need to include metastatic thyroid carcinoma in the differential diagnosis of miliary lung nodules.

Abdominal hemangiopericytoma scintigraphically simulating an accessory spleen.

Hemangiopericytoma is a soft tissue tumor composed histologically of pericytes of Zimmerman, which line capillaries. These neoplasms have been observed throughout the body in soft tissue and bone. Presented here is a case of abdominal hemangiopericytoma proven histologically that simulated an accessory spleen on a number of studies including Tc-99m sulfur colloid imaging.

Application of a hospital pharmacy computer system to nuclear pharmacy.

A hospitalwide decentralized computer system using the software module for outpatient pharmacy is applied to the nuclear pharmacy. Computer benefits of label production, medication profiling, permanent record keeping, inventory control, and screening for drug interactions are applicable in the nuclear pharmacy setting.