Dysfunction In Multiple Sclerosis Patients Research Articles

Memory impairment in multiple sclerosis: a quantitative review.

To assess the nature and magnitude of memory impairment in multiple sclerosis (MS), the authors analyzed quantitatively 36 studies comparing the memory performance of MS participants to healthy controls. The authors studied (a) the pattern of impairment across short-term memory (STM), working memory (WM), and long-term memory (LTM); (b) the moderating influence of retrieval support on LTM impairment; (c) the covariation of WM and LTM impairment; and (d) the moderating influence of clinical characteristics of the MS sample on memory impairment. The analyses revealed significant impairment across all memory domains and failed to support a retrieval-based account of LTM dysfunction in MS patients. In addition, robust associations were found between clinical features of MS and memory impairment. The findings suggest a more global pattern of memory deficits in MS than has been previously believed, with deficits clearly associated with neurological disability and disease course.

VEP-flash mapping in clinical practice

Abnormalities in the ocular-motor reflex recorded in electronystagmography may indicate central vestibular system impairment. Multiple sclerosis (MS) is the most common chronic, debilitating disease characterized by focal demyelinization that develops throughout the central nerves system at varying time. The aim of the study was to apply the quantitative analysis of ocular-motor tests to evaluation degree of the central system impairment in MS patients.The study was carried on 60 MS patients consulted in Balance Division, Otolaryngology Clinic, Medical University of Lodz, from 2002 to 2004, and 50 healthy persons as the control group. Clinical otoneurolaryngological examinations and electronystagmography tests (smooth pursuit, optokinetic, saccades) were performed in all patients. We apply the quantitative Z score analysis for gain in smooth pursuit test, slow phase velocity in optokinetic, maximal velocity of the saccades. Depending on Z score value the patients were qualified into one of three scale dysfunctions.Statistical correlation were found between results of all ocular-motor tests outcome in MS patients and control group. In smooth pursuit test most often second degree (35.0%), in OKN test first degree (28.3%) and in saccades the third degree (31.6%) of dysfunction was observed. The higher the values of Z score, the more abnormal results of ocular-motor reflex were observed.Application of the quantitative Z score analysis of the ocular-motor tests results demonstrating the degree of central ocular-motor system dysfunction in MS patients. This method may assist in monitoring the central vestibular system impairment and in evaluation course of the disease and degree of neurological disability.

Vestibular and Other Balance Disorders in Multiple Sclerosis: Differential Diagnosis of Disequilibrium and Topognostic Localization

Disorders of balance and equilibrium are common in multiple sclerosis (MS). This article reviews areas of central nervous system anatomy that may be involved in MS disequilibrium as well as the role of clinical examination, electrophysiologic testing, and magnetic resonance imaging in the diagnosis and assessment of vestibular dysfunction in MS patients. Relevant literature is reviewed and a case history is presented.

Exposure times for colour discrimination in the parafoveal field: a new procedure to detect subtle visual dysfunction in multiple sclerosis patients.

A new procedure to test colour discrimination in the parafoveal field is described. This method was used on 25 healthy controls and 25 subjects having a definite clinical or laboratory-supported diagnosis of multiple sclerosis, with or without a previous history of optic neuritis. The test proved to be sensitive in detecting visual dysfunction even in some patients in whom the standard technique of pattern-reversal evoked potential recordings yielded a normal result.

Flash electroretinogram abnormalities in patients with clinically definite multiple sclerosis.

We studied the flash electroretinograms (ERGs) of 105 patients with multiple sclerosis who were divided into four groups. The first group had no history or clinical evidence of optic nerve dysfunction, the second and third groups had either left or right optic nerve disease respectively, and the fourth group had historical or clinical evidence of bilateral optic nerve disease. Statistical analysis of the data using analysis of variance (ANOVA) showed that the group of patients with no history or clinical evidence of optic nerve disease had no significant difference from the control group for their peak b-wave implicit times but the other three groups were significantly delayed on the affected side(s). Using the Mann-Whitney U-test we found all four patient groups had significantly greater absolute interocular latency differences from the control group. The electroretinal contribution to flash VEP delay was also investigated. In those patients with unilateral or bilateral optic nerve disease we found that in 14-31% of those patients with flash VEP delay there was also abnormal prolongation of the ERG b-wave. These results confirm a high incidence of retinal dysfunction in multiple sclerosis patients and may suggest that transynaptic degeneration of retinal structures occurs in optic nerve demyelination. The significant absolute interocular latency difference in particular may provide another electrophysiological parameter to establish a diagnosis of multiple sclerosis in suspect cases.

Hair follicle discrimination dysfunction in multiple sclerosis patients.

A method was developed of assessing somatosensory deficits quantitatively using hair follicle displacement as a stimulus within a psychophysical signal detection task paradigm. Multiple sclerosis patients with and without somatosensory disturbances could be differentiated and compared with normal subjects. This method may distinguish patients with somatosensory dysfunction, and dorsal funiculus neuropathology may underlie this distinction.