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H N Wellman

Publications and source records attributed to H N Wellman.

At least 37 records · Page 2Linked to original sources
PubMed1987

Efficacy of thyroid scintigraphy in the diagnosis of intrathoracic goiter.

For evaluation of the usefulness of thyroid scintigraphy in the diagnosis of intrathoracic goiter, we analyzed the results of radionuclide thyroid scintigraphy in 54 consecutive cases with suspected upper mediastinal masses. Intrathoracic goiters were found in 42. The sensitivity, specificity, and accuracy of the scintigraphy for intrathoracic goiter were 93% (39/42), 100% (12/12), and 94% (51/54), respectively. Scintigraphic morphology, scanning technique, and pitfalls are discussed. The results show that most intrathoracic goiters do have thyroid function and that radioiodine scintigraphy is a definitive and cost-effective diagnostic procedure for this disease.

Adult↗
PubMed1986

Pulmonary thromboembolism: current status report on the role of nuclear medicine.

The normal perfusion study continues indisputably to rule out the presence of pulmonary embolism (PE) with reasonable certainty. However, the abnormal perfusion study requires additional specificity. Many retrospective and one prospective correlation of contrast pulmonary angiography (CPA) have largely substantiated the efficacy of ventilation imaging and increasing specificity, especially with a high-probability (HP) interpretation to approximately a 90% predictive value. In most studies, the predictive value of a low-probability (LP) interpretation also approaches 90%. Intermediate-probability (IP) ventilation-perfusion (V-P) studies are the most frequent reason for performing pulmonary angiography, although LP studies with a stated prior clinical HP should also have CPA. Ventilation imaging technique is not as uniformly established as for perfusion studies, leading to some continued variability in interpretative criteria; yet criteria proposed by Biello and his colleagues have begun to be widely adopted. Aerosol inhalation imaging is developing, but has not been widely used, while problems continue with central airways deposition. The importance of contemporary correlative chest x-rays (CXR) especially when normal, have been emphasized, as well as new findings of the import of serial post-V-P CXRs, especially in HP studies without CPA or negative CPA. CPA continues to be the most specific diagnostic test for PE when properly performed, and is complimented and enhanced by use of prior V-P findings; although it is clear that too few CPAs are being performed. Consequently, there has been too much clinical dependence on V-P imaging. The value of prospective clinical probability estimates in patient management has been better substantiated. Reemphasis on thromboembolism as a systemic disease with use of some objective evaluation of the presence of peripheral thrombosis is becoming a part of clinical rationale, with the integrated long-leg radionuclide venograms (RNV) being one of the reasonable approaches. Multicenter studies have demonstrated, contrary to prior contentions, that V-P imaging leads to a significant net reduction and use of anticoagulants, as well as having overall significant efficacy in effecting patient management in suspected PE. Some of the controversies surrounding V-P imaging are expected to be resolved with the completion of the ongoing multiinstitute Prospective Investigation of Pulmonary Embolic Diagnosis (PIOPED) study.(ABSTRACT TRUNCATED AT 400 WORDS)

Aerosols↗
PubMed1986

Indeterminate lung imaging. Can the number be reduced?

During a 2 1/2-year period, 1131 patients with suspected pulmonary embolism had ventilation-perfusion lung scans; 150 of these patients also underwent pulmonary angiography. In a retrospective study, these 150 patients were re-evaluated using the reference criteria of Biello and Alderson, with 62% read as indeterminate. Twenty patients who had chronic obstructive pulmonary disease with retention of Xe-133 in greater than 50% of the lung fields without corresponding radiographic abnormality were included. Ventilation/perfusion matches and mismatches could be correctly determined in 15 of these patients. These 15 of 20 studies could be correctly reclassified as low-probability, while the other five remained indeterminate. With increasing intervals between ventilation/perfusion lung imaging and the onset of symptoms, the percentage of patients with proven pulmonary emboli correctly diagnosed as high probability continuously decreased, and the percentage of studies read as indeterminate constantly increased. Serial chest radiographs suggested that the development of infiltrates in the region of the embolus convert high-probability ventilation/perfusion scans to indeterminate.

Humans↗
PubMed1986

Localization of technetium-99m pertechnetate in peripheral nerve tumors.

Technetium-99m pertechnetate scintigraphy in three patients with pathologically proven peripheral nerve tumors (six in total) demonstrated its ability to assess accurately the size, location, and the extent of all lesions. Pertechnetate localized only in areas of abnormal nerve involvement and all lesions were better seen in delayed images than the earlier ones. Pertechnetate imaging appears to be a promising method of noninvasive evaluation of clinically evident and occult tumors of peripheral nerve origin.

Adult↗
PubMed1986

Acetazolamide enhancement of HIPDM brain flow distribution imaging.

Six patients with symptomatic cerebral vascular disease were studied with 133Xe regional cerebral blood flow measurements and HIPDM cerebral imaging after the administration of acetazolamide. The results obtained from this small group suggest this technique may have high sensitivity for detection of cerebral vascular disease.

Acetazolamide↗
PubMed1986

Clinical comparison of indium-111 acetylacetone and indium-111 tropolone granulocytes.

This clinical study compares the efficacy of two 111In white blood cells preparations. Seventy-six patients were imaged after an injection of granulocytes (GRAN) isolated on a Ficoll-Hypaque gradient and labeled with [111In]acetylacetone (ACAC) in saline; 105 patients were imaged after an injection of GRAN isolated on a metrizamide-plasma gradient and labeled with [111In]tropolone (TROP) in plasma. Early (2-4 hr), intermediate (4-6 hr), and delayed (24 hr) images were obtained. The specificity was quite high (94-100%) in both preparations and no statistical differences could be found. The sensitivity for ACAC-GRAN for the early, intermediate, and delayed images were 39%, 63%, and 64%, respectively; for TROP-GRAN it was 80%, 89%, and 92%, respectively. In all cases the TROP-GRAN images were significantly more sensitive than the ACAC-GRAN images obtained at the same time after injection (p less than 0.001 for early and delayed images, 0.01 less than p less than 0.025 for intermediate images). For ACAC-GRAN the intermediate and delayed images were significantly more sensitive than the early images, while no significant difference could be found for TROP-GRAN. In a blinded experiment, the ability of TROP-GRAN to demonstrate a lesion was compared to that of ACAC-GRAN. TROP-GRAN demonstrated the lesions better than ACAC-GRAN, both in the early and late images (p less than 0.001). TROP-GRAN visualization scores at 4-6 hr equaled those obtained 24 hr after injection. In conclusion, GRAN separated and labeled in plasma with TROP are superior to those separated and labeled in saline with ACAC in three ways: higher visualization scores, earlier visualization of the lesion, and greater sensitivity.

Adolescent↗
PubMed1985

Comparison of technetium-99m sulfur colloid and in vitro labeled technetium-99m RBCs in the detection of gastrointestinal bleeding.

Twenty-seven paired Tc-99m sulfur colloid (SC) and Tc-99m RBC studies were evaluated for the detection of GI bleeding. The only two positive Tc-99m SC studies had positive early Tc-99m RBC studies as well. There were 15 other positive Tc-99m RBC studies (three during the first hour) and these were associated with normal Tc-99m SC scans. Approximately 70% of the positive Tc-99m RBC studies occurred after 1 hour. Tc-99m RBCs should be the initial test in patients with GI bleeding.

Adolescent↗
PubMed1984

Gastric emptying of enteric-coated tablets.

To evaluate the gastric emptying time of pharmaceutical dosage forms in a clinical setting, a relatively simple dual-radionuclide technique was developed. Placebo tablets of six different combinations of shape and size were labeled with indium-111 DTPA and enteric coated. Six volunteers participated in a single-blind and crossover study. Tablets were given in the morning of a fasting stomach with 6 oz of water containing 99mTc pertechnetate and continuously observed with a gamma camera. A scintigraph was obtained each minute. The results suggested that the size, shape, or volume of the tablet used in this study had no significant effect in the rate of gastric emptying. The tablets emptied erratically and unpredictably, depending upon their time of arrival in the stomach in relation to the occurrence of interdigestive myoelectric contractions. The method described is a relatively simple and accurate technique to allow one to follow the gastric emptying of tablets.

Adult↗
PubMed1984

In-111 granulocyte response to intervening surgery. Evidence of sustained in vivo viability.

A patient with chronic osteomyelitis had surgery performed between the early and delayed images of an In-111 granulocyte scan. The early images showed no uptake, while the delayed images demonstrated marked soft tissue uptake, which was felt to be secondary to the inflammation of the intervening surgery. It was concluded that granulocytes, when labeled with In-111, remain viable and can respond to inflammation that occurs after their injection.

Adult↗
PubMed1984

Evaluation of complicating osteomyelitis with Tc-99m MDP, In-111 granulocytes, and Ga-67 citrate.

Studies with gallium-67 and three-phase bone imaging (TPBS), though very sensitive, are not very specific in evaluating suspected osteomyelitis (OM) that is superimposed upon other diseases causing increased bone turnover. A total of 57 patients with suspected OM were studied; this included 48 with increased bone turnover. All of the patients were studied with granulocytes labeled with In-111 acetylacetone (In-111 GRAN), TPBS and 29 of these patients had Ga-67 studies as well. In-111 GRAN had a sensitivity of 100% in acute OM and 60% in chronic OM, with a specificity of 96%. Gallium-67 was excellent in ruling out OM when the study was normal, or in ruling in OM when the relative uptake of Ga-67 exceeded the uptake of Tc-99m MDP, or when the Ga-67 in bone had a different distribution from the TPBS. Unfortunately, these criteria were met in only 28% of our subjects. We conclude that when added to TPBS, the In-111 GRAN study plays an important role in detecting complicating OM.

Acute Disease↗
PubMed1984

Stoichiometric Tc-99m RBC labeling using stable kit solutions of stannous chloride and EDTA: concise communication.

An in vitro Tc-99m labeling method is described, which utilizes stable stock solutions of stannous chloride and disodium edetate (EDTA). The kit procedure requires as little as 1 ml of patient blood, can be performed in only 15 min, and gives labeling yields in excess of 98%. By using EDTA, the binding capacity of RBCs for technetium is sufficient to produce Tc-99m RBC doses with specific concentration greater than 50 mCi/ml for first-pass cardiac studies. Scintigrams reveal a slight amount of bladder activity and splenic uptake, but at no time has the thyroid, stomach, or normal bowel been visualized. The predominant 20-hr blood-clearance half-time results in excellent image quality for over 24 hr--an essential property for following intermittent GI bleeding or for performing repeat cardiac function studies over a several-hour time interval.

Edetic Acid↗
PubMed1983

Wedged Swan-Ganz catheter causing ventilation-perfusion mismatch. Case report and review of the literature.

A ventilation-perfusion (V/Q) lung scan in a postoperative patient with a Swan-Ganz catheter showed an area of mismatch suggesting pulmonary embolism. Radiographs, as well as failure to get a venous return from the catheter suggested wedging. A pulmonary angiogram, performed after the Swan-Ganz catheter was pulled back, was essentially normal. An autopsy performed within 24 hours of the lung scan did not reveal pulmonary emboli. Wedged Swan-Ganz catheter was probably responsible for the V/Q mismatch.

Catheterization↗
PubMed1982

Usefulness of bone marrow imaging in childhood malignancies.

Two hundred six technetium-99m sulfur colloid bone marrow scans in 110 pediatrics patients were reviewed. The normal distribution of sulfur colloid in the lower extremities in various age groups was established. There was progressive loss of uptake with increasing age from less than two years to greater than ten years. Tumor replacement was seen as regions of decreased radioactivity, and the extent of the scan defect paralleled the response of the disease to therapy. Both chemotherapy and irradiation resulted in an extension of the Tc-99m SC to peripheral marrow sites. In irradiated areas, marrow scan defects were demonstrated and generally recovered normal activity by six months after the completion of therapy. Marrow scan abnormalities caused by tumor replacement were present in four patients despite normal bone scans and radiographs. Ultimate confirmation of tumor involvement was by needle aspiration or biopsy. Persistent marrow defects were seen in two patients with neuroblastoma who had remission of their disease: biopsy revealed myelofibrosis. Technetium-99m sulfur colloid bone marrow scanning is a sensitive monitor of altered marrow activity associated with pediatric hematologic or oncologic diseases.

Bone Marrow↗
PubMed1982

Tc-99m diphosphonate imaging in the differential diagnosis of thyroid nodules.

Early Tc-99m diphosphonate (DP) imaging was performed in 122 patients with cold thyroid nodules in an effort to differentiate benign nodules from malignant. Immediately upon completion of the routine 24-hour I-123 uptake and multiview pinhole imaging, Tc-99m DP was injected intravenously and three serial 3-minute anterior images of the thyroid gland were obtained. Follow-up information was available in 85 patients. All cystic lesions had less Tc-99m uptake as compared with the uptake in the normal parts of the thyroid. However, 48 of 50 solid nodules had Tc-99m DP uptake to the same or greater degree than did the normal gland. The other two had mixed pattern on ultrasound examination. Most of the carcinomas (8 of 10) and benign adenomas (15 of 22) had identical appearance on Tc-99m scans, i.e., uptake in the lesion being the same as in the normal thyroid. It appears that by using this technique it is possible to separate solid nodules from cystic, but not benign from malignant.

Diagnosis, Differential↗
PubMed1981

Feasibility of low doses of I-131 for thyroid ablation in postsurgical patients with thyroid carcinoma.

The feasibility of using low doses of I-131 (30 mCi) for ablation of thyroid remnants following surgery for papillary and follicular thyroid carcinoma was examined in 21 patients. Six weeks following near-total thyroidectomy and three days following intramuscular thyroid-stimulating hormone (10 IU), patients were given 30 mCi of I-131 and scans were performed 24 to 72 hours later. Remaining thyroid tissue was identifiable in the thyroid bed in 19 patients, and two patients also had evidence of cervical metastases. Patients with metastases received an additional 100 mCi of I-131. Follow-up I-131 scans were performed at nine to 15-month intervals in ten patients who initially received 30 mCi of I-131, and only one patient showed complete ablation of the residual thyroid tissue, whereas the remaining nine patients had persistent uptake of I-131 in the same regions in which the uptake was seen in the initial postoperative scans. One of the nine patients had evidence of a cervical metastasis as well. It is therefore apparent that total or near-total thyroidectomy rarely removes all thyroid tissue and that an "out-patient" dose of I-131 is not adequate for ablation of postoperative thyroid remnants.

Adenocarcinoma↗