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M D Okerlund

Publications and source records attributed to M D Okerlund.

14 recordsLinked to original sources
PubMed1988

Gallium uptake in the thyroid gland in amiodarone-induced hyperthyroidism.

Amiodarone is an iodinated antiarrhythmic agent that is effective in the treatment of atrial and ventricular arrhythmias. A number of side effects are seen, including pulmonary toxicity and thyroid dysfunction. A patient with both amiodarone-induced pneumonitis and hyperthyroidism who exhibited abnormal gallium activity in the lungs, as well as diffuse gallium uptake in the thyroid gland is presented. The latter has not been previously reported and supports the concept of iodide-induced "thyroiditis" with gallium uptake reflecting the inflammatory response.

Amiodarone↗
PubMed1988

Diagnosis of recurrent hyperparathyroidism: comparison of MR imaging and other imaging techniques.

Several reports have indicated good results with MR imaging of hyperparathyroidism. However, its use in recurrent hyperparathyroidism has not been assessed separately. Thirty patients with recurrent hyperparathyroidism were evaluated by MR with both T1- and T2-weighted images. Twenty-six and 23 of these patients, respectively, also had thallium-201 scintigraphy and high-resolution sonography. For the 28 patients who eventually had surgical exploration and histologic evidence of adenoma (21 cases) or hypoplasia (seven cases), MR accurately located abnormal parathyroid glands in 75% evaluated prospectively and 89% evaluated retrospectively. Scintigraphy located 68% prospectively and 76% retrospectively. Sonography detected 57% prospectively and 67% retrospectively. For patients undergoing three studies, the prospective and retrospective detection rate was significantly better (p less than .05) for MR compared with sonography but was not significantly different for MR and scintigraphy. MR detected three of four mediastinal adenomas evaluated prospectively and retrospectively. One false-positive case was seen with MR, one with scintigraphy, and one with sonography. Thus, MR can be used to locate abnormal parathyroid tissue at a rate equal to or better than scintigraphy or sonography.

Adenoma↗
PubMed1987

Hyperparathyroidism: comparison of MR imaging with radionuclide scanning.

Twenty-three patients with hyperparathyroidism were evaluated preoperatively with magnetic resonance (MR) imaging. Twenty patients also underwent thallium-201/technetium-99m scintigraphy. Of 22 patients with primary hyperparathyroidism, 12 had persistent or recurrent disease. One had secondary hyperparathyroidism due to end-stage renal disease. MR imaging allowed accurate localization of abnormal parathyroid glands in 64% evaluated prospectively and 82% evaluated retrospectively. Scintigraphy allowed localization of 60% evaluated prospectively and 70% retrospectively. The two imaging modalities together allowed detection of 68% evaluated prospectively and 91% retrospectively. MR imaging allowed detection of two of five mediastinal adenomas evaluated prospectively and four of five retrospectively. In patients who underwent both imaging studies, MR was more successful in those with previous neck surgery (73% evaluated prospectively and 91% retrospectively) than in those with no prior surgery (57% prospectively and 71% retrospectively). Scintigraphy allowed accurate localization in 64% evaluated prospectively and 64% retrospectively in patients with previous surgery versus 57% prospectively and 86% retrospectively in patients with no prior neck surgery. Four false-positive results were obtained with MR imaging and three with scintigraphy. MR imaging was useful for parathyroid localization in patients with hyperparathyroidism, particularly in patients requiring additional surgery.

Adult↗
PubMed1986

Parathyroid imaging: comparison of double-tracer (T1-201, Tc-99m) scintigraphy and high-resolution US.

Parathyroid scintigraphy using a double-tracer (T1-201, Tc-99m) subtraction technique depicted 17 of 23 (74%) parathyroid adenomas in patients with and without previous neck operations. High-resolution (10-MHz) ultrasound (US) depicted 18 (78%) of these adenomas. Average tumor size depicted by US was 17 X 10 X 8 mm (excluding a giant adenoma) and 19 X 10 X 9 mm by scintigraphy. Alone, neither modality was particularly sensitive in the depiction of primary hyperplasia of the parathyroid glands, but combined techniques were more effective than the use of a single modality. With both US and T1-201 scintigraphy, only two of 23 cases of parathyroid adenoma in the neck were missed, and none of the eight cases of secondary hyperplasia were missed. In 11 patients who had previously undergone neck surgery, parathyroid tumors were identified in eight by either US or double-tracer scintigraphy. Preoperative parathyroid imaging with double-tracer scintigraphy and high-resolution US is suggested for patients with hyperparathyroidism, particularly in those patients who have had previous parathyroid surgery.

Adenoma↗
PubMed1985

Localization studies in patients with persistent or recurrent hyperparathyroidism.

Preoperative localization studies are essential for patients who have undergone previous parathyroid operations. This is because the remaining parathyroid glands are more difficult to identify at operation because of increased scarring with loss of normal tissue planes and because the remaining abnormal parathyroid tissue is more likely to be situated in an ectopic position. This investigation concerns the accuracy of preoperative localization studies in 36 consecutive patients. All patients had symptoms and clinical and laboratory data diagnostic of primary (31 patients) or secondary (five patients) hyperparathyroidism. Ultrasonography was performed in all 36 patients; 18 (50%) were positive, 14 (39%) were negative, and four (11%) were false positive examinations. Eight of the negative study results occurred in patients with abnormal parathyroid glands situated in the mediastinum. Computerized tomography (CT) was performed in 25 patients. There was an equal number of positive (11; 44%) and negative (11; 44%) studies with three (12%) false positive test results. CT was helpful in identifying substernal lesions and other abnormal parathyroid glands situated in ectopic positions. Thallium chloride 201-technetium 99m pertechnetate scans were used in 22 patients. There was an equal number of positive (eight; 36%) and negative (eight; 36%) studies. Six patients (27%) had false positive scans. One or more of these noninvasive tests was positive in 27 of the 36 patients (75%). Highly selective venous catheterization for the measurement of immunoreactive parathyroid hormone concentrations localized the elusive parathyroid tumor in 12 of the 16 patients (75%) overall and in six of the nine patients (66%) whose tumors were not identified by other studies. One patient had both a false positive ultrasound and thallium chloride 201-technetium 99m pertechnetate scan. Preoperative localization studies were therefore very helpful for locating hyperfunctioning parathyroid glands in patients with recurrent or persistent hyperparathyroidism, and 75% of the tumors were identified by noninvasive studies. Seventy-five percent of the tumors not identified by noninvasive studies were localized by selective venous catheterization. Most tumors not identified by noninvasive studies were mediastinal or ectopic in position.

Adult↗
PubMed1984

A new method with high sensitivity and specificity for localization of abnormal parathyroid glands.

A novel method for localization of abnormal parathyroid glands involving color-processing of nuclear scintigrams of the neck after injection of Thallium-201 and Technetium pertechnetate is presented with surgical correlation. Preoperative localization of single parathyroid adenomas was successful in 88% of previously unoperated patients and in 85.7% of those with adenomas not located at previous surgery. Eighty-three per cent of glands with secondary hyperplasia, 66% of glands with primary hyperplasia, and one carcinoma were localized. No abnormal studies were seen in non-hyperparathyroid hypercalcemia, and no false positive studies were seen. Localization appeared related to larger adenomas (300-5000 mg), although one of 60 mg was localized. Color-comparison dual-isotype scintigraphy was useful for localization of parathyroid adenomas and hyperplastic glands and exceeded the reported sensitivity of either ultrasonography or computerized tomography. It deserves wider evaluation in preoperative management of at least hyperparathyroidism of the primary or persistent types.

Adenoma↗
PubMed1982

Carcinoma of the thyroid with a mixed medullary and follicular pattern: morphologic, immunohistochemical, and clinical laboratory studies.

We recently encountered an unusual carcinoma of the thyroid gland with a predominantly medullary pattern admixed with areas of follicular differentiation. Both patterns prevailed at the primary site and in bilateral cervical lymph node metastases. The tumor cells were stained for calcitonin by indirect immunofluorescence technique and were found to contain dense-core granules by electron microscopy. Calcitonin was demonstrated in tumor homogenates by radioimmunoassay and was elevated in the serum. Immunofluorescence staining also revealed thyroglobulin in the neoplastic cells. Moreover, following total thyroidectomy, the cervical node metastases concentrated radioactive iodine (131I), and serum thyroglobulin was increased at one stage of the disease when measured by radioimmunoassay. These findings are discussed in the light of the dual embryonic derivation of the thyroid gland.

Adult↗