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Biomedical subjects

D B Hier

Publications and source records attributed to D B Hier.

At least 73 records · Page 4Linked to original sources
PubMed1985

Fungal infections of the central nervous system: comparative analysis of risk factors and clinical signs in 57 patients.

Risk factors and clinical manifestations of fungal infections of the CNS were analyzed in 57 autopsied patients. Aspergillosis occurred in 16, candidiasis in 27, and cryptococcosis in 14. Nine of 31 variables studied showed significant difference (p less than 0.01). Cryptococcosis was community-acquired in 93%; whereas, aspergillosis and candidiasis were nosocomial in more than 95%. Focal neurologic deficits developed in 50% with CNS aspergillosis, but in only 4% with candidiasis. Meningeal signs occurred in 86% with CNS cryptococcosis, but in only 6% with aspergillosis and 7% with candidiasis. Discriminant analysis demonstrated that CNS aspergillosis was most frequently a nosocomial infection with focal neurologic deficits, pulmonary infiltrates, and hypercortisolemia. Cryptococcosis was generally a non-nosocomial infection with meningeal signs presenting in an ambulatory population. CNS candidiasis was a clinically occult nosocomial fungal infection with generally no deficits or meningismus, occurring most frequently in the neonate, the elderly, and surgical patients. The discriminant functions, which correctly classified 91% of these CNS fungal infections, may be applicable in clinical diagnosis.

Adult↗
PubMed1985

Anticoagulant-related intracerebral hemorrhage.

Twenty-four patients had intracerebral hemorrhage while they were being treated with anticoagulants. Hypertension was present in 67% of the cases, head trauma was an uncommon preceding event, and simultaneous bleeding in other organs occurred in only one instance. Neurologic abnormalities progressed for several hours in 58%. Seizures occurred at onset in 12.5%. The location of the hemorrhage was as follows: cerebellum (nine cases), lobar white matter (six), basal ganglia (five), thalamus (two), and hemisphere, unspecified (two). In 61%, the hemorrhages occurred within 6 months of therapy. In 75%, the prothrombin time was beyond 1 1/2 times the control value. Mortality was 62.5%. Survivors had smaller hematomas than did patients with fatal hemorrhage.

Adult↗
PubMed1985

Occlusive disease of the middle cerebral artery.

We studied 20 patients with severe occlusive disease of the mainstem middle cerebral artery (MCA) or its major division branches, and 25 patients with internal carotid artery (ICA) disease. MCA disease patients were more often black, female, younger, and had fewer TIAs than the ICA disease patients. Neurologic signs in patients with MCA disease evolved progressively during days to weeks, whereas ICA disease patients more often had an acute onset of nonprogressive deficits. CT commonly showed restricted subcortical or wedge-shaped infarcts in MCA disease patients. All MCA disease patients had stroke, but 40% of ICA disease patients had no infarction. MCA lesions usually affected the mainstem MCA or its major superior division. Patients with MCA disease seldom had recurrent ischemia in the same vascular territory as the stroke and had a low incidence of subsequent cardiac death.

Adult↗
PubMed1984

Aphasia after left thalamic infarction.

We examined a 70-year-old woman who became aphasic after a left thalamic infarction. Computed tomographic scan showed injury that was largely limited to the ventral anterior and rostral ventral lateral thalamic nuclei. Speech was characterized by reduced voice volume, impaired auditory and reading comprehension, perseverations, intermittent use of jargon, fluctuations in the ability to perform confrontation naming, extraneous intrusions, verbal paraphasia, intact repetition skills, and fluent speech that was laconic but grammatically correct. We propose that the deficits after left thalamic injury can be grouped into the following four large clusters: extrapyramidal deficits (decreased or fading voice volume), deficits in lexical access (anomia, verbal paraphasia), deficits in vigilance (neologisms, intrusions, fluctuating performance, jargon, perseverations), and comprehension defects.

Aged↗
PubMed1984

Intrusions and perseverations.

Twenty-two subjects with presumed senile dementia of the Alzheimer's type (SDAT), twenty-two with dementia other than SDAT, twenty with aphasia, and seventeen healthy controls over 50 years of age were examined for intrusions and perseverations. Perseverations were defined as the immediate inappropriate repetition of a prior response whereas intrusions were defined as the inappropriate repetition of prior responses after intervening stimuli. Intrusions and perseverations occurred in demented and aphasic subjects, but were rare in controls. Intrusions occurred most often in SDAT or Wernicke aphasia, but also in dementia other than SDAT. Intrusions were not correlated with dementia severity. Intrusions are a useful sign of dementia, but they cannot be considered pathognomonic of SDAT. They appear to arise when subjects are unable to access correct responses from long-term memory and instead substitute erroneous responses selected from short-term memory. Perseverations were most common in the Wernicke aphasics and subjects with dementia due to communicating hydrocephalus. Although frontal lobe dysfunction is prominent in communicating hydrocephalus, it is absent in cases of Wernicke aphasia. Thus, we have confirmed prior suggestions that perseveration can occur in the absence of frontal lobe injury. Failure to self-monitor speech as well as an inability to change mental set probably plays an important role in the genesis of perseverations. There was no statistically significant correlation between dementia severity and number of perseverations. Low correlations were found between intrusions and perseverations suggesting that these seemingly similar behaviors are distinct and are probably produced by separate neuropsychological mechanisms.

Age Factors↗
PubMed1984

Altered patterns of word associations in dementia and aphasia.

The word associations of 38 demented, 17 aphasic, and 22 normal subjects were studied. Both normal and brain-injured subjects appear to make judgments about the grammatical class of the word stimulus. Certain stimulus words (especially nouns and adjectives) elicit paradigmatic responses whereas other words (especially verbs and adverbs) elicit syntagmatic responses. The mechanism producing syntagmatic responses seems relatively resistant to deterioration in dementia or aphasia. However, in dementia the mechanism that generates paradigmatic responses becomes progressively less efficient (possibly due to a loss of semantic markers) and consequently more random (idiosyncratic) responses emerge. Perseverative responses, inhibited in normal subjects, are more prevalent in dementia. Anomic aphasics show a pattern of word associations similar to that of subjects with mild dementia. Broca's aphasics, while making fewer paradigmatic associations than normals, retain enough self-monitoring mechanisms so that few idiosyncratic and perseverative responses are made while more null responses occur. Wernicke's aphasics show a marked shift away from a paradigmatic word association strategy, possibly due to an inability to access semantic markers or a true loss of these markers. Metalinguistic deficits (i.e., a failure to adopt an appropriate strategy) may also contribute to this shift away from paradigmatic associations. Furthermore, a disruption of self-monitoring mechanisms in Wernicke's aphasia leads to an increase in perseverative and idiosyncratic responses.

Aged↗
PubMed1984

Intracerebral hemorrhage secondary to cerebral amyloid angiopathy.

Cerebral amyloid angiopathy (CAA) is a cause of intracerebral hemorrhage in a significant proportion of normotensive patients. Two cases of pathologically proved multiple intracerebral hemorrhages due to CAA are reported. These hemorrhages are accurately demonstrated on computed tomography and are typically superficial in location. CAA should be considered as a cause of such hemorrhages in elderly patients who are often normotensive and demented.

Aged↗
PubMed1984

Racial differences in the distribution of anterior circulation occlusive disease.

We compared clinical and angiographic features of 26 white and 45 black patients with symptomatic occlusive cerebrovascular disease. White patients had more transient ischemic attacks, carotid bruits, and more severe occlusive disease of the internal carotid artery origin. Blacks had more severe disease of the middle cerebral artery stem and supraclinoid internal carotid arteries. Differences were not explained by racial differences in the prevalence of hypertension, diabetes, hypercholesterolemia, or ischemic heart disease. Since the middle cerebral artery lesions in blacks do not correlate with other accepted epidemiologic, clinical, and laboratory markers of atherosclerosis, the lesions may arise from a disorder that differs from atherosclerosis.

Aged↗
PubMed1984

Caudate hemorrhage.

We studied 12 patients with intracerebral hemorrhage in the head of the caudate nucleus. These cases accounted for 7% of a consecutive series of intracerebral hemorrhage. The clinical findings differed from more common varieties of supratentorial hemorrhage. All patients had acute onset of vomiting, headache, stiff neck, decreased level of consciousness, and behavioral changes in a pattern that simulated subarachnoid hemorrhage. Seven patients had gaze paresis and hemiparesis, with or without sensory loss. Two of these seven patients had, in addition, elements of Horner's syndrome. The prognosis for recovery was good. No patient had recurrent hemorrhage or persistent hydrocephalus.

Adult↗
PubMed1983

A case of subcortical dementia due to sarcoidosis of the hypothalamus and fornices.

A patient with sarcoidosis involving predominantly the hypothalamus and fornices was evaluated for dementia. He showed a relative sparing of fund of knowledge and orientation. Memory skills, particularly short-term memory, were severely impaired. Behavioral changes included apathy and a lack of spontaneity. Insight was relatively preserved. The pattern of his deficits showed some similarities to the pattern reported in patients with Huntington's disease and was different from that described in Alzheimer's disease. The dementia caused by subcortical pathology may differ in important respects from that caused by diffuse cortical dysfunction.

Adult↗
PubMed1983

Behavioral abnormalities after right hemisphere stroke.

We evaluated 41 patients with unilateral right hemisphere strokes for hemiparesis, hemianopia, constructional apraxia, neglect, extinction, unilateral spatial neglect on drawing (USND), dressing apraxia, anosognosia, prosopagnosia, and motor impersistence. Low correlations were found among USND, neglect, and extinction. Constructional apraxia showed a higher correlation with USND than with hemianopia. Motor impersistence and anosognosia correlated with the severity of the hemiplegia. Left neglect, motor impersistence, and anosognosia tended to occur only with large strokes. Injury to the right parietal lobe appears to be an important determinant of USND and constructional apraxia. In most cases of motor impersistence, left neglect, and anosognosia, there was injury to the right parietal lobe and also to structures beyond the parietal lobe. In two cases, small deep lesions produced behavioral abnormalities comparable to those of larger superficial cortical lesions.

Apraxias↗
PubMed1983

Recovery of behavioral abnormalities after right hemisphere stroke.

We studied recovery of function in 41 patients with right hemisphere stroke. Recovery was rapid for left neglect, prosopagnosia, anosognosia, and unilateral spatial neglect on drawing (USN). Recovery was slower for h mianopia, hemiparesis, motor impersistence, and extinction. Rates of recovery were intermediate for constructional apraxia and dressing apraxia. Sex had no influence on the rate of recovery. Younger patients recovered from prosopagnosia more rapidly than older patients. Patients with smaller lesions recovered more quickly from anosognosia, USN, and hemiparesis than patients with larger lesions. Patients with hemorrhages recovered more rapidly from constructional apraxia, neglect, and motor impersistence than patients with infarcts. Recovery of function and the factors influencing recovery can by studied systematically by life table methods.

Age Factors↗
PubMed1982

Spatial ability in androgen-deficient men.

Several lines of previous evidence have suggested that androgens affect cognitive abilities. In an effort to characterize this defect, we compared 19 men with idiopathic hypogonadotropic hypogonadism with 19 control men and with five men with acquired hypergonadotropic hypogonadism that had developed after puberty. The 19 patients with idiopathic hypogonadism had markedly impaired spatial ability in comparison to either controls or subjects with acquired hypogonadism (P less than 0.05). Moreover, the spatial ability of the patients correlated positively with their testicular volume (P less than 0.05). Androgen-replacement therapy in six of the patients did not improve their spatial ability. The impairment in spatial ability in men with the idiopathic form of hypogonadotropic hypogonadism, the lack of such an impairment in men with the acquired form, and the failure to exogenous androgens to correct the deficits in the idiopathic form suggest that androgens exert a permanent organizing influence on the brain before or at puberty in boys.

Adult↗
PubMed1982

Visuospatial deficits after right hemisphere stroke.

The influence of visuospatial deficits on functional status after right hemisphere stroke was investigated in 34 patients. Correlation coefficients between visuospatial deficits and other factors--age, sex, vocabulary, educational level, hemiparesis, hemianopia, left-sided extinction, length of stay on a rehabilitation unit, and time lapse between onset of stroke and admission to the rehabilitation unit--were also computed. Little correlation was found between the severity of the hemiparesis and the severity of the visuospatial deficits, yet both motor and visuospatial deficits proved to be important predictors of functional status at the time of discharge from the stroke rehabilitation unit. We conclude that visuospatial deficits are an important independent factor governing functional outcome and should be given as much attention as hemiparesis during discharge and rehabilitation planning for the right hemisphere stroke patient.

Age Factors↗
PubMed1981

Acquired learning disability for reading after left temporal lobe damage in childhood.

A 6-year-old boy developed hemorrhage in the left temporal lobe and subsequently underwent left temporal lobectomy. Afterwards, he was completely unable to learn to read or write. Psychological tests showed impairment in verbal learning and memory, with right ear and right visual field superiority in verbal perception. A Wada test showed no aphasia after right carotid injection. We conclude that damage to the speech-dominant temporal lobe resulted in the inability to learn to read or write. Despite the lesion, speech remained strongly lateralized to the left hemisphere, accounting for the right-sided advantage in verbal perception. Some patients with developmental dyslexia may have dysfunction of a strongly dominant left hemisphere rather than a delay or incompleteness of language lateralization.

Adult↗
PubMed1980

Cerebral asymmetry and verbal intellectual deficits.

In a group of 53 children and young adults with learning disability, reversed cerebral asymmetry as measured by CT scan correlated highly with the prevalence, and to some extent with the degree, of verbal intellectual deficit as measured by age-appropriate Weschler Intelligence Scales. A history of delayed speech also correlated with reversed asymmetry but was not associated with a greater degree of verbal intellectual deficit among the reversed-asymmetry cases.

Adolescent↗
PubMed1980

Learning disorders and sex chromosome aberrations.

No sex chromosome aberrations were detected in a prospective study of twenty adult dyslexic men. A retrospective study of eighty-nine subjects with known sex chromosome aberrations revealed twenty of them to be mentally-retarded. Among the sixty-nine subjects of normal intelligence, learning, speech and attention disorders were frequent. Children with 47,XYY, 47,XXY, and 47,XXX karyotypes appeared particularly prone to experience delays in speech development as well as later academic underachievement in language-related subjects. In contrast, speech development was normal in all of the girls with Turner's syndrome and later academic difficulties were usually confined to mathematics or science. Hyperactivity was noted with considerable frequency among 47,XYY and Turner's syndrome subjects, but not among subjects with a 47,XXX or 47,XXY karyotype.

Adolescent↗