Biomedical subjects

H S Levin

Publications and source records attributed to H S Levin.

At least 91 records · Page 5Linked to original sources

PubMed1994

Visual information processing after severe closed head injury: effects of forward and backward masking.

Three tachistoscopic tasks were employed to assess whether survivors of severe closed head injury (CHI) exhibit a disturbance of information processing within peripheral and/or central visual pathways. Twelve survivors of severe CHI and 12 individually matched control subjects completed a recognition threshold (no mask) task, a monoptic, forward masking by visual noise task (to assess processing within relatively peripheral pathways), and a dichoptic, backward masking by pattern task (to assess processing within central pathways). For each experimental procedure, the minimum exposure durations required by subjects to identify correctly single consonants and triple consonants were determined. Survivors of severe CHI showed deficits on all three visual tasks. Both groups also had higher threshold durations for the more complex stimuli (triple v single consonants), but differences in threshold were greater in the patients with CHI. The degree of perceptual impairment exhibited by patients with CHI was highly variable and not consistently related to injury characteristics or residual motor or speech and language impairment.

Adult↗

PubMed1994

Neurobehavioural consequences of closed head injury in older adults.

This study examined the neurobehavioural effects of closed head injury (CHI) in adults aged 50 years and older. Twenty two mild to moderate CHI patients who were within seven months of the injury were administered measures of language, memory, attention, and executive functioning. Compared with demographically similar normal controls, the patients exhibited significantly poorer functioning on the cognitive domains. Naming and word fluency under timed conditions, verbal and visual memory, and the ability to infer similarities were especially vulnerable. These initial findings indicate that CHI in older adults produces considerable cognitive deficits in the early stages of recovery. Future research should characterise long term outcome and the potential links between head injury and the development of progressive dementia.

Age Factors↗

PubMed1994

Dissociation between delayed alternation and memory after pediatric head injury: relationship to MRI findings.

This study investigated the usefulness of a delayed alternation task in characterizing the cognitive sequelae of closed head injury in children and adolescents. Verbal learning and memory (California Verbal Learning Test) were also studied for comparison. Sixty-two closed head injury patients (mean age, 9.6 years), who were studied after an average postinjury interval of 20 months, were divided according to both their lowest postresuscitation Glasgow Coma Scale score (3 to 8 versus 9 to 15) and age range (5 to 7 years versus 8 to 16 years) at the time of testing. Magnetic resonance imaging was performed to evaluate the relationship of focal brain lesions to cognitive and memory performance. Fifty-six neurologically normal children (mean age, 9.9 years) were tested on the same measures. The results disclosed no relationship between delayed alternation performance and severity of injury. In contrast, verbal memory was impaired in the severely-injured patients, relative to both controls and less severely-injured patients. Frontal lobe (but not extrafrontal) lesion size incremented the Glasgow Coma Scale score in predicting verbal memory, but there was no relationship between focal brain lesions and delayed alternation performance. In contrast to the tendency for more efficient delayed alternation performance in the 5- to 7-year-old subjects than in the 8- to 16-year-old subjects, verbal memory significantly improved with age in the closed head injury and control groups. Notwithstanding our essentially negative findings for delayed alternation, it is possible that this task may be useful for assessing frontal lobe injury in younger children or infants.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1993

Cognition in relation to magnetic resonance imaging in head-injured children and adolescents.

To investigate the relationship between cognitive sequelae and magnetic resonance imaging (MRI) findings following closed head injury of varying severity in the pediatric age range, 76 head-injured children and adolescents were studied at least 3 months after trauma and compared with 57 normal controls. Problem solving, planning, verbal and design fluency, memory, and response modulation were assessed. Significant effects of injury were obtained on all of the cognitive measures. Cognitive impairment was more consistently present on the various outcome measures in children who were 6 to 10 years old at the time of the study than in the older children and adolescents. Magnetic resonance imaging disclosed areas of abnormal signal in the frontal lobes of 42 patients, whereas focal lesions restricted to the extrafrontal region were found in 15 children. Regression analyses disclosed that taking into account the size of frontal lobe lesion enhanced the relationship between cognitive performance and the severity of injury.

Adolescent↗

PubMed1993

Effects of transcallosal surgery on interhemispheric transfer of information.

The effects of transcallosal surgery on interhemispheric transfer of information were investigated in five patients who underwent partial section of the corpus callosum for evacuation of a brain tumor. In comparison with normal controls, postoperative findings indicated subtle motor and/or sensory manifestations of hemispheric disconnection which tended to resolve overtime. However, in no case were the disconnection effects disabling in the performance of daily activities.

Adult↗

PubMed1993

Renal oncocytoma: clinical and biological correlates.

We treated 31 patients with renal oncocytoma. Renal cell carcinoma was found existing separately within the same or contralateral kidney in 10 patients (32%). Followup of 29 patients revealed 24 alive with no evidence of disease and 1 alive with recurrent oncocytoma, while 1 with coexistent tumors died of progressive renal cell carcinoma and 3 tumor-free patients died of unrelated diseases. Quantitative deoxyribonucleic acid analysis was performed on cell suspensions of fresh tumor by flow cytometry or by image cytometry on touch preparations from frozen tissue in 16 patients with renal oncocytoma. Ploidy analysis revealed all oncocytomas to be diploid. Frozen tissue immunohistology was performed using murine monoclonal antibody against human HLA-A, B and C (class I) antigens with the avidin-biotin peroxidase technique in 11 patients with renal oncocytoma. Ten oncocytomas did not express these self-recognition antigens and 1 was only weakly positive for antigen expression. In contrast, renal cell carcinomas strongly expressed HLA class I antigens. The high incidence of coexistence of renal oncocytoma and renal cell carcinoma has important clinical implications. Loss of HLA class I antigen expression by renal oncocytomas may provide an additional method for differentiating this lesion from renal cell carcinoma.

Adenoma, Oxyphilic↗

PubMed1993

Head trauma.

Progress in research includes studies concerning the pathophysiology and outcome of pediatric head injury, the pathology of the hippocampus in fatal injury, and the use of multivariate statistics to predict outcome in survivors. Recent research has confirmed and extended findings regarding the differential effects of closed head injury, depending on the age of the individual. These studies indicate that the consequences of head injury are more severe in older adults and in children younger than 2 years. Neuroimaging findings include evidence for delayed brain injury as a major cause of mortality and disability. Functional brain imaging provides evidence for cerebral dysfunction that is not appreciated by structural brain imaging techniques and may have a stronger relationship to neurobehavioral sequelae. The neurobehavioral sequelae frequently implicate frontal dysfunction, even in the absence of structural findings on computed tomography or magnetic resonance imaging. Studies of mild head injury have expanded our knowledge concerning the pathogenesis of postconcussional symptoms, including a preinjury vulnerability based on recent life events. Persistent postconcussional symptoms after mild head injury are frequently associated with emotional disturbance of clinical proportions.

Adolescent↗

PubMed1993

A comparison of psychiatric symptoms in vascular dementia and Alzheimer's disease.

OBJECTIVE: Psychiatric symptoms account for much of the morbidity of vascular dementia and Alzheimer's disease. The goals of this study were to extend previous observations of the psychopathology and behavioral problems associated with vascular dementia and to compare the profile of symptoms in patients with vascular dementia to that in patients with Alzheimer's disease. METHOD: Twenty-eight pairs of patients (one with vascular dementia and one with Alzheimer's disease) were matched with respect to education, age, and severity of dementia. Their psychiatric symptoms were assessed with the Neurobehavioral Rating Scale, a 28-item observer-rated instrument, and the Hamilton Depression Rating Scale, and the symptoms in the two diagnostic groups were compared. RESULTS: Blunted affect, depressed mood, emotional withdrawal, motor retardation, low motivation, anxiety, unusual thoughts, and somatic concerns occurred in more than one-third of the patients with vascular dementia. There was no significant relation between severity of cognitive impairment and severity of these noncognitive symptoms. The patients with vascular dementia had more impairment than the patients with Alzheimer's disease, as indicated by the Neurobehavioral Rating Scale total scores and scores on the behavioral retardation, anxiety/depression, and verbal output disturbance factors. They also had a higher total score on the Hamilton depression scale and higher scores on 14 of the 17 Hamilton depression items. CONCLUSIONS: Patients with vascular dementia have more severe behavioral retardation, depression, and anxiety than those with Alzheimer's disease when the groups have similar levels of cognitive impairment. This probably reflects the contrasting brain regions typically involved in the two disorders.

Aged↗

PubMed1993

Attentional disturbance after pediatric closed head injury.

The influence of severity of closed head injury and age on attentional functioning was prospectively investigated in 36 children (age range, 7 to 16 years) 6 months after injury. Children were placed into mild, moderate, and severe injury groups using established neurologic criteria. Each child received the Wechsler Intelligence Scale for Children-Revised Digit Span subtest and a continuous performance test. Children with severe closed head injury demonstrated significantly poorer continuous performance test scores than mildly or moderately injured children. Injury severity had no effect on Digit Span scores. Younger children exhibited more pronounced impairment on the continuous performance test relative to uninjured age peers. These results extend the persistence of attentional impairments beyond those of previous reports. Closed head injury is not associated with preferential sparing of sustained attention in younger children 6 months after injury. Brain injury earlier in life may result in delayed vulnerability of information processing skills.

Adolescent↗

PubMed1993

Prognostic features of primary and metastatic testis germ-cell tumors.

Careful pathologic analysis of a germ-cell tumor provides important prognostic data. The author describes the histopathologic features of the various types of germ-cell tumors that have prognostic implications and discusses the pitfalls in the sampling and examination of tissue specimens.

Humans↗

PubMed1992

Late MRI after head injury in children: relationship to clinical features and outcome.

To characterize the brain pathology in relation to long-term outcome after pediatric head injury, 55 children were studied by magnetic resonance imaging (MRI) at least 3 months after sustaining moderate to severe closed head injury (CHI). Thirty-nine of the patients had abnormal signal intensity consistent with residual brain lesions, including 28 children with lesions involving the frontal lobes. The clinical features of children with frontal lesions, extrafrontal lesions, and diffuse injury were compared. The analysis disclosed that children with frontal lobe lesions were more frequently disabled than children who sustained diffuse injury. Our MRI findings indicate that residual brain lesions are more common after moderate to severe CHI in children than previously thought and that the frontal lobes are most frequently involved. Further investigation is indicated to elucidate whether distinctive cognitive and behavioral sequelae are associated with frontal lobe lesions in children.

Adolescent↗

PubMed1992

Corpus callosum lesions after closed head injury in children: MRI, clinical features and outcome.

Thirty-four children who sustained moderate to severe closed head injury underwent magnetic resonance imaging (MRI). Eight (24%) had MRI evidence of corpus callosum injury, most commonly within the posterior body and splenium. In contradistinction to reports in adults, there was no definite relationship between callosal injury and lower initial Glasgow Coma Scale scores, nor was there a significantly higher incidence of primary brain-stem lesions, diffuse axonal shear injury or intraventricular hemorrhage. In none of these 8 children did the initial admission computed tomography show evidence of callosal injury. Callosal injuries on MRI are not necessarily a poor prognostic finding, the majority of the 8 children showing good functional recovery.

Adolescent↗

PubMed1992

Fibrotic lesions of the testicle: sonographic patterns mimicking malignancy.

All testicular sonograms performed over a 2.5-year period were retrospectively reviewed, yielding eight patients with pathologically proven lesions consisting primarily of tubular sclerosis and interstitial fibrosis. Only two patients (25%) had a palpable abnormality. A variety of sonographic patterns was found, including focal hypoechoic or hyperechoic lesions and diffuse heterogeneity of the testicular parenchyma. The clinical and sonographic findings prompted open biopsy or orchiectomy in all cases. In the same time period, nine pathologically proven testicular malignancies were evaluated sonographically and displayed either well-defined hypoechoic or diffusely heterogeneous echo patterns. All but two of these patients (78%) had palpable abnormalities. This study demonstrates a significant overlap in the sonographic appearance of benign fibrotic lesions and testicular malignancies. When careful palpation of a sonographically heterogeneous or focal hypoechoic lesion fails to reveal a mass and serum tumor markers are negative, an open biopsy with frozen section analysis should be considered rather than proceeding directly to orchiectomy. Homogeneously hyperechoic masses can be considered benign and do not require surgery.

Adult↗

PubMed1992

Narrative discourse after closed head injury in children and adolescents.

This study examined narrative discourse in 20 children and adolescents at least 1 year after sustaining a head injury. Narratives were analyzed along the dimensions of language structure, information structure, and flow of information. Severity of impaired consciousness was associated with a significant reduction in the amount of language and information. The most important finding which emerged was the disruption in information structure. This pattern confirms the impression of disorganized discourse in severely injured children. Explanations for the disruption in information structure are explored in terms of the role of vocabulary, memory, and localization of lesion according to magnetic resonance imaging. In view of recent evidence that frontal lobe damage is associated with discourse formulation deficits in adults and is the most common site of focal lesion in closed head injury, we examined discourse patterns in individual patients with frontal lobe lesions. Preliminary data from our single-case studies suggest discourse patterns similar to those reported for adults with frontal lobe injuries.

Adolescent↗

PubMed1992

Adrenal carcinosarcoma presenting in a woman with clinical signs of virilization. A case report with immunohistochemical and ultrastructural findings.

An adrenal carcinosarcoma is reported in a 29-year-old female presenting with clinical signs of virilization. This is the first reported case of a functioning adrenal carcinosarcoma in the English language literature. The tumor measured 12.5 cm in greatest dimension, weighed 610 g, and consisted of large areas of typical adrenal cortical carcinoma that was, however, interspersed with multiple foci of sarcoma. Rhabdomyosarcomatous elements were identified and confirmed both immunohistochemically and ultrastructurally. After radical resection, the patient received adjuvant mitotane therapy but developed rapid local and metastatic recurrence. Systemic chemotherapy was unsuccessful, and the patient died 8 months after surgery.

Adrenal Cortex Neoplasms↗

PubMed1992

Assessment of cognitive, psychiatric, and behavioral disturbances in patients with dementia: the Neurobehavioral Rating Scale.

OBJECTIVE: To assess the validity of the Neurobehavioral Rating Scale (NRS) in patients with Alzheimer's disease (AD) or multi-infarct dementia (MID) and to characterize the cognitive, psychiatric, and behavioral disturbances that occur in these patients. DESIGN: Cross-sectional evaluation. SETTING: West Los Angeles VAMC Geropsychiatry Inpatient Unit, Neurobehavior Inpatient Unit, and Dementia Clinic; UCLA Alzheimer's Disease Clinic. PATIENTS: Convenience sample of 61 patients with AD and 22 patients with MID. MAIN OUTCOME MEASURE: The NRS, a 27-item observer-rated instrument that measures cognitive, psychiatric, and behavioral disturbances. RESULTS: The NRS demonstrated content and convergent validity in this patient group. Principal components analysis of the NRS ratings identified a six-factor solution, and each factor contained clinically related symptoms. The factors were Cognition/Insight, Agitation/Disinhibition, Behavioral Retardation, Anxiety/Depression, Verbal Output Disturbance, and Psychosis. Among the patients with AD, agitation, disinhibition, hostility, poor insight, poor motivation, suspiciousness, and delusions were more severe in patients with more advanced dementia. Depressive symptoms occurred with equal severity in patients with mild and advanced dementia, but depressed mood was more severe in patients with earlier age of onset of AD. CONCLUSION: The NRS is a useful instrument for structured assessment of a broad range of cognitive, psychiatric, and behavioral disturbances in patients with dementia.

Aged↗

PubMed1992

Serial MRI and neurobehavioural findings after mild to moderate closed head injury.

Fifty patients who sustained mild to moderate closed head injury (CHI) underwent a CT scan, MRI, and neurobehavioural testing. At baseline 40 patients had intracranial hyperintensities detected by MRI which predominated in the frontal and temporal regions, whereas 10 patients had lesions detected by CT. Neurobehavioural data obtained during the first admission to hospital disclosed no distinctive pattern in subgroups of patients characterised by lesions confined to the frontal, temporal, or frontotemporal regions, whereas all three groups exhibited pervasive deficits in relation to normal control subjects. The size of extraparenchymal lesion was significantly related to the initial Glasgow Coma Scale score, whereas this relation was not present in parenchymal lesions. One and three month follow up MRI findings showed substantial resolution of lesion while neuropsychological data reflected impressive recovery. The follow up data disclosed a trend from pervasive deficits to more specific impairments which were inconsistently related to the site of brain lesion. These results corroborate and extend previous findings, indicating that intracranial lesions detected by MRI are present in most patients hospitalised after mild to moderate CHI. Individual differences in the relation between site of lesion and the pattern of neuropsychological findings, which persist over one to three months after mild to moderate CHI, remain unexplained.

Adult↗

PubMed1992

Severe head injury in children: experience of the Traumatic Coma Data Bank.

The outcome at discharge, 6 months, and 1 year after they had sustained severe head injuries was investigated in children (0-15 yr old at injury) who were admitted to the neurosurgery service at one of four centers participating in the Traumatic Coma Data Bank. Of 103 eligible children, the quality of recovery was assessed by the Glasgow Outcome Scale (GOS) at 6 months after injury in 92 patients (86% of series) and at 1 year in 82 patients (73% of series). The lowest post-resuscitation Glasgow Coma Scale score and pupillary reactivity were predictive of the 6-month GOS as were their interaction. Analysis of the first computed tomographic scan disclosed that bilateral swelling with/without midline shift was related to a poor outcome as was the presence of mass lesions. Comparison of age-defined subgroups of patients revealed that outcome was poorest in the 0- to 4-year-old patients, as reflected by their mortality, which increased to 62% by 1 year. Distinctive features of the injuries in the 0- to 4-year-olds included evacuated subdural hematomas (20% of patients) and hypotension (32% of patients). The most favorable outcome was attained by 5- to 10-year-olds (2/3 had a good recovery by 1 yr), whereas the GOS distribution of adolescents was intermediate between the children and adults. In summary, the GOS data reflect heterogeneity in the quality of outcome after severe head injury depending on age, neurological indices, and computed tomographic scan diagnostic category.

Adolescent↗