USE OF MIDDLE-FIELD MRIWITH SPECIFIC SEQUENCIES COMPENSATING THE MOVEMENT ARTEFACTS FOR BRAIN STUDIES IN PATIENTS WITH HIV INFECTION

Abstract

Nowadays of great importance is not only the issue of early diagnosis of HIV infection, but of early detection and effective treatment of AIDS complications. The annual increase in the incidence of HIV infection amounts to 4%. Unfortunately, a great number of patients ask for hospital care when their disease has the stage of secondary complications. Such situation requires a fast and affordable diagnostics together with verification of the nature of the affection. Purpose. To evaluate the diagnosis effectiveness of the secondary infectious cerebral affection in patients with HIV infection using the method of non-contrast MRI including the usage of the specially developed software. One hundred thirty three patients were recruited for the study, the main group of 108 persons (as old as 36,8±8,3), all referred to the brain MRI with suggestion of neurologic complications of HIV. The control group comprised 25 patients of the same age with focal damage of vascular nature. In everybody the MRI has been carried out using open middle-field scanner (Az-360, by AZ plc company, Moscow) with field induction 0,4 T, supplied with wireless four-channel quadratur coil for head studies, without contrast enhancement, but using in everybody the specially designed protocols for compensation of movement artifacts. All patients were re-examined in 2, 4 and 6 weeks. MRI images both in first admission and in follow-up studies were reported first qualitatively by type of contour of pathologic focus, by presence of multiple pattern of focal damage, by ultrastructure of foci, extent of perifocal oedema, interhaemispheric dislocation; also the dimensions of lateral ventriculi, of external subarachnoidal spaces and thickness of cortex in various regions were measured. Focal cerebral damage verified later as toxoplasmosis was revealed in the main group in 80% (86 of 108) of patients. False-negative and false-positive conclusions of MRI studies were not revealed also in prospective follow-up studies. Of these in 69 (80,2%) the pathologic foci were multiple and did localize periventricularly in particular in putamen, nucleus caudatus, equally frequent for both haemispherae, single foci were detected in thalami, concomitant with tendency to extensive cortical dystrophy. The putamen region was involved more frequently as compared to other basal ganglii (р=0,003). No significant differences were revealed between various cortical regions as regard to frequency of detection of pathologic foci. Four weeks period was detected as being the most effective time for the dynamic control in the course of treatment. Conclusion. Middle-field MRI of the brain with compensation of movement artifacts is a proper technique for both the diagnosis and follow-up control of treatment of cerebral toxoplasmosis in patients with HIV infection.