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Biomedical subjects

M A Ron

Publications and source records attributed to M A Ron.

At least 55 records · Page 3Linked to original sources
PubMed1992

Clinically isolated lesions of the type seen in multiple sclerosis: a cognitive, psychiatric, and MRI follow up study.

There is a dearth of longitudinal studies on psychometric and psychiatric change in multiple sclerosis (MS) particularly on the evolution of these abnormalities early in the disease process. A 4 1/2 year follow up study documenting magnetic resonance imaging (MRI), psychometric, and psychiatric abnormalities was undertaken in a group of 48 patients with clinically isolated lesions--for example, optic neuritis--which are frequently the harbinger of MS. At follow up about half the subjects had developed clinically definite MS, with memory deficits becoming apparent. Deficits in attention documented at initial assessment were present but unchanged in those subjects who still had a clinically isolated lesion status. However, after MS was categorised into a relapsing-remitting or chronic progressive course, patients with a chronic progressive course were found to have significantly deteriorated with regard to auditory attention tasks. T1 relaxation times in apparently normal white matter correlated with certain indices of cognitive impairment. In developing a model to explain the pathogenesis of intellectual and emotional change in MS, the interaction of organic, psychological, and social factors needs to be emphasised.

Adult↗
PubMed1992

Psychiatric morbidity in patients with peripheral vestibular disorder: a clinical and neuro-otological study.

This study reports the psychiatric morbidity in 54 patients with objective evidence of peripheral vestibular disorder seen three to five years after their original referral. A third of the patients were free from vestibular symptoms at follow up and a further third had experienced some improvement. Two thirds of the patients had experienced psychiatric symptoms during this period, although only 50% were rated above the cut off point for significant psychiatric disturbance when interviewed. Panic disorder with or without agoraphobia and major depression were the commonest psychiatric diagnoses. Patients with classical "labyrinthine" symptoms had a more severe canal paresis than the rest, but the degree of the abnormalities in the neuro-otological tests was unrelated to outcome or to psychiatric morbidity. On the other hand, there was a significant correlation between the presence of vestibular symptoms and psychiatric morbidity, which in turn correlated with measures of anxiety, perceived stress and previous psychiatric illness.

Adolescent↗
PubMed1992

Psychotic illness in multiple sclerosis. A clinical and magnetic resonance imaging study.

Ten patients with multiple sclerosis (MS) and psychosis were assessed using the Present State Examination, and matched retrospectively with respect to age, disability, duration of symptoms, and disease type with 10 MS patients without psychosis. Both groups underwent MRI of the brain. There was a trend for the psychotic group to have a higher total lesion score, particularly around the periventricular areas. This reached statistical significance in the areas around the temporal horn. In all cases, neurological symptoms preceded the onset of psychosis. The psychotic group also had a later age of onset of psychosis than psychotic patients without brain disease. These results point to an aetiological association between the pathological process of MS and psychosis.

Adult↗
PubMed1991

The effect of chlorpromazine and methylprednisolone on NMR relaxation times in the normal cat brain.

This small experimental study describes the effects on the NMR relaxation times in normal cat brain of a 5-day course of high dose methylprednisolone and, separately, a 1-month course of standard dose daily chlorpromazine. Methylprednisolone had no influence on T1 or T2 in these tissues, but chlorpromazine produced a transient fall of T1 of thalamus, and rise in T2 of white matter: both normalize after 4 weeks. The mechanism of these changes is unknown. It is concluded that these drugs should not interfere with the quantitative MRI monitoring of brain abnormalities in patients receiving them, although the unlikely occurrence of longer term effects of chlorpromazine has not been excluded.

Animals↗
PubMed1991

Sources of T1 variance in normal human white matter.

The major factors contributing to T1 variance at 0.5 T in white matter were studied in healthy people. Anatomical location of the white matter sampled and differences between individuals contributed 74% of the total variance in serial measurements of the same subjects. There was also significant change over time within an individual subject that could not be attributed to machine drift. This information permitted estimates to be made concerning adequate sample size in future studies that examine for pathological white matter T1 change.

Adolescent↗
PubMed1991

Cognitive abnormalities in multiple sclerosis: a psychometric and MRI study.

This study reports the cognitive abnormalities of a group of 58 patients with definite multiple sclerosis (MS). The psychometric functions measured were: 'IQ deficit', verbal and visual memory, abstracting ability, visual and auditory attention and naming ability. The presence of brain pathology was investigated using magnetic resonance imaging (MRI). A group of 46 physically disabled controls without significant brain disease was used for comparison. Normative MRI data were obtained from a group of 40 normal volunteers. The psychometric performance of the MS group was compared to the previously reported findings in patients with clinically isolated syndromes. MS patients had widespread cognitive deficits sparing naming ability and affecting verbal memory less severely than other intellectual functions. The overall performance on psychometric tests was related to the severity of the MRI abnormalities and to the duration of the illness, but was not significantly influenced by the presence of psychiatric morbidity or the degree of physical disability. Patients with clinically isolated syndromes occupied an intermediate position between MS patients and disabled controls in terms of cognitive and MRI abnormalities.

Activities of Daily Living↗
PubMed1991

MRI in schizophrenia: basal ganglia and white matter T1 times.

The T1 relaxation time of the basal ganglia (putamen, globus pallidus and head of caudate) and of the frontoparietal centrum semiovale was compared between 49 schizophrenic patients and 36 healthy controls. Previous reports of increased T1 time in the basal ganglia were not confirmed, and group differences were not detected within the white matter. Within patients T1 values could not be related to tardive dyskinesia or other clinical features. Normal variation seen in basal ganglia T1 times is described for the first time: lowest values occur in the globus pallidus and highest in the caudate, and values within the putamen increase rostrally.

Adult↗
PubMed1990

Psychosis associated with demonstrable brain disease.

Sixty-five psychotic patients with unequivocal evidence of brain pathology and a variety of neurological disorders were assessed with respect to phenomenology and outcome. No relationship was found between site of brain pathology and type of psychotic disorder. A majority of patients had a syndrome indistinguishable from schizophrenia without coarse brain involvement and shared similar variables predicting outcome of psychosis, thus raising important issues concerning their nosological status.

Adolescent↗
PubMed1990

Positive diagnosis of self-medication with homatropine eye drops.

A 25-year-old man with a variety of unusual ocular symptoms was fully investigated and no abnormality discovered. The suspicion of self-medication with a mydriatic was confirmed when homatropine was isolated in his tears. We describe a method for collecting tears which allowed biochemical confirmation at leisure.

Adult↗
PubMed1989

Psychiatric morbidity in multiple sclerosis: a clinical and MRI study.

This study reports the psychiatric morbidity in 116 patients with definite multiple sclerosis (MS). The presence of brain pathology was investigated using magnetic resonance imaging (MRI). A group of 48 physically disabled controls suffering from rheumatic or neurological conditions not involving the brain was used for comparison. Normative MRI data were obtained from a group of 40 healthy volunteers. Psychiatric morbidity was significantly higher in the MS group with nearly half of the patients scoring as cases at interview. There was no evidence to suggest that psychiatric symptoms in isolation were the first manifestation of MS in the present material. The presence of psychiatric illness at interview was significantly related to the degree of social stress as perceived by the patient. The severity of MRI abnormalities was greater in those with longer histories and greater physical disability, but did not show a significant relationship with global measures of psychiatric disability. Of the various psychiatric symptoms elation was significantly correlated with the presence of widespread MRI abnormalities, while flattening of affect, delusions and thought disorder correlated with the degree of pathology in the temporo-parietal region.

Adult↗
PubMed1989

Cognitive impairment in patients with clinically isolated lesions of the type seen in multiple sclerosis. A psychometric and MRI study.

This study reports the performance on psychometric tests of a group of 48 patients with clinically isolated lesions of the type seen in multiple sclerosis (optic neuritis, brainstem and cord lesions). The cognitive functions studied were: 'IQ deficit', verbal and visual memory, abstracting ability, visual and auditory attention, and naming ability. The presence of brain pathology was investigated by means of magnetic resonance imaging (MRI). A group of 46 patients with rheumatic and neurological conditions not known to cause brain disease was used for comparison. Normative MRI data were obtained from a group of 40 normal volunteers. An overall 'Cognitive Ability Index' was significantly worse in patients with clinically isolated lesions when compared with physically disabled controls. IQ deficit and defective auditory attention were the more severely affected parameters. These deficits were significantly correlated with the duration of neurological symptoms and with the degree of brain pathology detected by MRI.

Adult↗
PubMed1989

Absence of central functional cholinergic deficits in myasthenia gravis.

Sporadic reports have suggested central involvement in myasthenia gravis, a disorder in which there is an antibody-mediated loss of peripheral nicotinic acetylcholine receptors. Five patients with symptomatic myasthenia gravis performed an auditory vigilance test of ability to direct and sustain attention, presumed to reflect central cholinergic function. No deficits were found, either in comparison with the same subject's performance when muscle strength had improved after plasma exchange, or compared with that of healthy controls. The results thus failed to substantiate reports of functionally significant central cholinergic deficits in myasthenia gravis.

Adult↗
PubMed1988

Agenesis of the corpus callosum and schizophrenia: a case report.

Clinical, radiological and neuropsychological findings in the first reported case of schizophrenia with complete agenesis of the corpus callosum are described. Although causal inferences were made difficult by the co-existence of a left frontotemporal cyst and a family history of affective disorder, some theories of the role of callosal dysfunction in schizophrenia require revision in the light of this case.

Agenesis of Corpus Callosum↗
PubMed1988

Psychiatric morbidity in patients with clinically isolated lesions of the type seen in multiple sclerosis: a clinical and MRI study.

This study reports the psychiatric morbidity in 76 patients with clinically isolated lesions of the type seen in multiple sclerosis (optic neuritis, brain stem and cord lesions). The presence or absence of brain pathology was investigated using magnetic resonance imaging (MRI). A group of 33 patients suffering from rheumatic and neurological conditions not known to involve the brain was used for comparison. Normative MRI data were obtained from a group of 40 normal volunteers. Over half of the patients with the clinical presentation of single lesions had MRI abnormalities in the brain, but past and present psychiatric morbidity were similar in patients and controls and no significant associations were found between the presence of MRI abnormalities and psychiatric morbidity. The degree of social stress experienced by the patients with clinically isolated lesions appeared to be highly relevant in the causation of psychiatric symptoms.

Adolescent↗