Faculty Bibliography

BACKGROUND: Both systemic and primary central nervous system (CNS) non-Hodgkin's lymphomas (NHL) occur in people with acquired immune deficiency syndrome (AIDS). The radiographic manifestations may be similar to other neoplasms and opportunistic infections that are also found frequently in AIDS. Furthermore, these diseases may coexist with NHL in the AIDS patient. METHODS: To evaluate the use of Tc-99m Lymphoscan (the Fab' fragment of the anti-CD-22 antibody LL-2; Immunomedics, Inc., Morris Plains, NJ) in patients with suspected AIDS lymphoma, we studied 7 patients with 35 sites of suspected disease. Six had CNS lesions suspicious for parenchymal brain lymphoma. Each patient underwent planar and single photon emission computed tomography imaging at 3-5 and 18-24 hours after administration of Lymphoscan. Scintigraphic results were compared with results of conventional diagnostic modalities. RESULTS: Overall, the sensitivity of Lymphoscan was 92% and the specificity was 86%. In brain lesions, there was 100% sensitivity and 100% specificity. Lymphoscan also had 100% sensitivity for sites of lymphomatous lymphadenopathy and for liver involvement. Although less specific in extracranial sites, Lymphoscan was correctly negative in sites of coexisting adenocarcinoma and pneumonia. Two patients had both parenchymal CNS and systemic lymphoma proven by biopsy. CONCLUSIONS: Lymphoscan appears to be a sensitive and specific method for diagnosing CNS lymphoma in AIDS patients. Although slightly less specific in extracranial sites, it may be helpful in differentiating lymphoma from other etiologies in these patients at risk for multiple neoplasms and opportunistic infections

We have developed a graphical interface which allows users of varying levels of computer experience and proficiency to manipulate medical image-processing data with 'point-and-click' ease. The power which had formerly been associated with protocols and shell scripts has been combined with the flexibility and 'user-friendliness' of buttons and dialog boxes

A method of image analysis was developed for correlation of hemangiomas detected at computed tomography (CT) and/or magnetic resonance (MR) imaging with increased blood pool activity evident at single photon emission CT (SPECT) performed after labeling of red blood cells with technetium-99m. Image analysis was performed in 20 patients with 35 known hepatic hemangiomas. After section thickness and pixel sizes of the different studies were matched, intrinsic landmarks were chosen to identify anatomically corresponding locations. Regions of interest (ROIs) drawn on the CT and/or MR images were translated, rotated, and reprojected to match the areas of interest on the corresponding SPECT images by means of a two-dimensional polynomial-based warping algorithm. Analysis of ROIs on 30 SPECT-MR and 20 SPECT-CT pairs of registered images provided absolute confirmation that 34 suspected hemangiomas identified on SPECT images correlated exactly with lesions seen on CT and/or MR images. Accuracy of fusion was within an average of 1.5 pixels +/- 0.8 (+/- 1 standard deviation). The technique enabled diagnostic confirmation of hemangiomas as small as 1.0 cm and proved useful for evaluating lesions located adjacent to intrahepatic vessels

A 48-yr old man noted gradual onset of pain, and paresthesia on the lateral aspect of his right leg. The findings were suggestive of S1 root compression. CT of spine was normal. Physical examination revealed a small mass overlying the right fibular head. CT revealed this to be a cystic mass. At surgery a ganglion cyst compressing the common peroneal nerve was found. Peripheral nerves may be compressed by ganglia producing a syndrome mimicking central nerve root compression. CT is the modality of choice for detection of these lesions