ABSTRACT
For the first time, human immunodeficiency virus (HIV)-associated vacuolar myelopathy (VM) was detailed in an autopsy-based study of 89 cases in 1985. This condition is the most common cause for spinal cord lesions in HIV patients. VM's pathogenic mechanism remains unclear; however, it is assumed that the disease can be related to both, the direct neurotoxic impact of the HIV and HIV-induced activation of immunopathological processes in the central nervous system (CNS). Reviewed in this paper is a case where the VM presentation deteriorated drastically when treated with highly active antiretroviral therapy, and almost completely regressed after the patient received the intravenous immunoglobulin (IVIg) treatment. The considered case demonstrates the viability of IVIg treatment in patients with HIV-associated CNS pathology, particularly when autoimmune reactions are suspected. The results of placebo-controlled studies of IVIg in patients with HIV-associated myelopathy may give a reliable evaluation of IVIg use in this context.
ABSTRACT
BACKGROUND: To study the integrity of white matter, we investigated the correlation between the changes in neuroradiological and morphological parameters in an animal model of acute obstructive hydrocephalus. METHODS: Hydrocephalus was induced in New Zealand rabbits (n = 10) by stereotactic injection of kaolin into the lateral ventricles. Control animals received saline in place of kaolin (n = 10). The progression of hydrocephalus was assessed using magnetic resonance imaging. Regional fractional anisotropy (FA) and the apparent diffusion coefficient (ADC) were measured in several white matter regions before and after the infusion of kaolin. Morphology of myelinated nerve fibers as well as of the blood-brain barrier were studied with the help of transmission electron microscopy (TEM) and light microscopy. RESULTS: Compared with control animals, kaolin injection into the ventricles resulted in a dramatic increase in ventricular volume with compression of basal cisterns, brain shift and periventricular edema (as observed on magnetic resonance imaging [MRI]). The values of ADC in the periventricular and periaqueductal areas significantly increased in the experimental group (P < 0.05). FA decreased by a factor of 2 in the zones of periventricular, periaqueductal white matter and corpus collosum. Histological analysis demonstrated the impairment of the white matter and necrobiotic changes in the cortex. Microsctructural alterations of the myelin fibers were further proved with the help of TEM. Blood-brain barrier ultrastructure assessment showed the loss of its integrity. CONCLUSIONS: The study demonstrated the correlation of the neuroradiological parameters with morphological changes. The abnormality of the FA and ADC parameters in the obstructive hydrocephalus represents a significant implication for the diagnostics and management of hydrocephalus in patients.
