Faculty Bibliography

Thirty-six patients with primary hyperparathyroidism were studied preoperatively by thallium-201 and technetium-99m pertechnetate subtraction (Tl-201/Tc-99m) scintigraphy, high-resolution real time ultrasonography and computed tomographic (CT) scanning. None of the patients had had previous surgical treatment of the parathyroid or thyroid glands. All of the patients underwent systematic bilateral exploration of the neck. All of the patients were successfully explored and 41 abnormal parathyroid glands were identified. Five patients had two adenomas. In six instances, adenomas were identified in ectopic anatomic sites. The sensitivity of correctly localizing the abnormal glands with these techniques was 49 per cent for the Tl-201/Tc-99m scintigraphy, 34 per cent for ultrasonography and 41 per cent for CT scanning. The Tl-201/Tc-99m scintigrams detected two of the six ectopically located adenomas, CT detected one, while ultrasound detected none. The five patients with multiple adenomas were not accurately identified as having multiple gland enlargement by any of these studies. Therefore, preoperative localization studies with these three techniques did not provide reliable information for initial bilateral exploration of the neck

Fourteen patients with suspected adenocarcinoma of the gastrointestinal tract received 1 mg of 111In-labeled anticarcinoembryonic antigen monoclonal antibody type ZCE025 combined with 40 mg unlabeled antibody of the same type. Planar and single-photon emission CT (SPECT) imaging studies were performed 3 days after infusion and, when possible, 7 days after infusion. Scan findings were correlated with the findings at surgery when possible. Tumor was detected by day-3 planar imaging in eight of 13 patients in whom tumor was documented histopathologically. Day-3 SPECT allowed demonstration of tumor in 11 of these 13 patients. In another patient whose scan was negative, no residual tumor was found at surgery. SPECT was particularly helpful in identifying small and midline tumors. In two cases, localization on SPECT helped identify the tumor mass on CT. Two primary tumors weighing less than 5 g could not be detected on either planar or SPECT scans. Histologically positive, normal-sized lymph nodes were not seen by planar imaging or SPECT. SPECT increased the detection rate over that achieved with planar imaging, helped to better localize scan abnormalities, and afforded more useful comparison between the monoclonal antibody study and CT

A case of unilateral mismatch on a ventilation/perfusion lung scan due to aortic aneurysm dissection is presented. Pulmonary embolism should not be considered the sole cause of unilateral lung mismatch. Clinical evaluation and pulmonary angiography should be used for a definitive diagnosis

Computed tomography was performed in 100 patients for additional evaluation of suspected skeletal metastases following radionuclide bone scanning in 86 patients and conventional radiography in all. A retrospective review of these cases revealed that the majority (78%) involved the spine and pelvis. Computed tomography contributed to the diagnosis of a malignancy by revealing a definite destructive lesion of bone in 27 patients who had an abnormal radionuclide bone scan, a normal or inconclusive radiograph, or both. It excluded a malignant lesion in 19 patients. In 38 patients, computed tomography provided additional information that contributed to such aspects of patient care as obtaining tissue diagnosis, determining the extent of lesions, and evaluating the response to treatment. False diagnoses were made in two patients. Detection by computed tomography of a skeletal lesion and histologic documentation, frequently by computed tomography-guided percutaneous needle aspiration biopsy, greatly curtailed an otherwise extensive search for the primary site. Furthermore, this information altered the treatment plan by obviating the need for radical resection or biopsy of the primary tumor and by directing the choice of an appropriate chemotherapeutic regimen

Eighty-six [67Ga]citrate chest scans were performed in 71 adult patients with the acquired immunodeficiency syndrome. Forty-five of these patients also had Kaposi's sarcoma. Only 29 of 57 abnormal scans were correlated with abnormal chest radiographs. Chest radiographs were negative for 27 scans and unavailable for one. Several scan patterns were seen. Diffusely increased lung uptake was seen most commonly with Pneumocystis carinii pneumonia, but also other infections and noninfectious inflammatory conditions. Focal uptake corresponding to regional lymph node groups occurred most often with Mycobacterium avium-intracellulare but aslo with lymphoma. Localized intrapulmonary uptake was seen in bacterial pneumonias. Perihilar activity occurred in two cases. When chest radiographs were abnormal and 67Ga scans negative, the most common diagnosis was pulmonary Kaposi's sarcoma

Lymphoscintigraphy results in 35 stage I melanoma patients were compared with primary location and surgical management. Six of 25 primaries with potentially multidirectional lymphatic drainage had drainage to one regional node group. Three of 10 with expected unidirectional drainage showed multidirectional drainage. With unidirectional drainage, decision concerning lymphadenectomy was simplified