title: MRI of the brain in HIV-positive patients: what is the value of routine intravenous contrast medium?
abstract: Our purpose was to assess the value of routine administration of intravenous gadolinium-DTPA (Gd-DTPA) for cranial MR in a series of human immunodeficiency virus (HIV)-positive patients. Two radiologists retrospectively reviewed 150 consecutive examinations of 104 patients. All patients underwent unenhanced and contrast-enhanced images. Each radiologist independently assessed first the unenhanced images alone and then the pre- and postinjection images together. Then both reviewed the complete study and produced a consensus report. The history, investigations and management were collated separately and were unknown to the radiologists. Contrast-enhanced T1-weighted images showed new focal abnormalities, not seen on the T2-weighted or unenhanced images in 15 (14 %) patients, but almost always in the context of abnormal unenhanced images. In only 2 patients (2 %) did contrast medium reveal abnormalities when the unenhanced study had been considered normal. In only 1 of these (1 %) was the new finding, cytomegalovirus diffuse ependymal enhancement, of clinical importance, although the diagnosis of encephalitis was made on routine examination of cerebrospinal-fluid. The other revealed a toxoplasma lesion in a patient known to have resolving disease. Meningeal disease not suspected on the unenhanced images was shown in 2 patients (2 %). In these case the unenhanced images were abnormal in other respects. Intravenous Gd-DTPA was helpful to the radiologist in making a radiological diagnosis in 11 patients (11 %), usually by improving characterisation of a lesion seen on the unenhanced images. The contribution of intravenous Gd-DTPA in this series does not warrant recommending its use in every case.
authors.affiliation: Department of Radiology, Guy's & Thomas' Trust, St. Thomas' Hospital, London SE1 7EH, UK.
authors.forename: P N
authors.initials: PN
authors.lastname: Malcolm
authors.forename: D C
authors.initials: DC
authors.lastname: Howlett
authors.forename: A
authors.initials: A
authors.lastname: Saks
authors.forename: N A
authors.initials: NA
authors.lastname: Smith
authors.forename: A K
authors.initials: AK
authors.lastname: Banerjee
authors.forename: J S
authors.initials: JS
authors.lastname: Bingham
authors.forename: J B
authors.initials: JB
authors.lastname: Bingham
authors.forename: T C
authors.initials: TC
authors.lastname: Cox
mesh_terms: D015526:AIDS Dementia Complex / Q000175:diagnosis*; D017088:AIDS-Related Opportunistic Infections / Q000175:diagnosis*; D000328:Adult; D001921:Brain / Q000473:pathology; D001927:Brain Diseases / Q000175:diagnosis*; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA