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Biomedical subjects

H S Levin

Publications and source records attributed to H S Levin.

At least 19 recordsLinked to original sources
PubMed1996

Dyscalculia and dyslexia after right hemisphere injury in infancy.

OBJECTIVE: To use the findings from neuropsychological evaluation and functional magnetic resonance imaging (fMRI) to assess interhemispheric reorganization of function after early unilateral brain injury. DESIGN AND METHODS: The study focused on one case of early brain injury that resulted in both dyscalculia and dyslexia. Brain injury was studied using both structural and fMRI. Intellectual function was evaluated using the Wechsler Intelligence Scale for Children, Third Edition, while visuospatial skills were assessed using the Block Design subtest of the Wechsler Intelligence Scale for Children, Third Edition, and Judgment of Line Orientation subtest. The Selective Reminding Test and the Recurring Figures Test were used to evaluate memory and orientation; language and speech skills were evaluated using the Boston Naming Test, Controlled Oral Word Association, Gates-MacGinitie Reading Test, and color naming. Various methods were used to study arithmetic skills, including the Wide Range Achievement Test-Revised and the Peabody Individual Achievement Test. The control group for fMRI consisted of nine normal subjects. SETTING: Neuropsychological laboratory in primary care hospital. PATIENT: A 17-year-old boy who had sustained a closed head injury associated with a partially depressed, right parietal skull fracture, and right temporal hemorrhage in a motor vehicle crash at age 7 months (November 9, 1977). Subsequent social behavior was normal, but the patient had difficulty throughout school in mathematics and spelling and was characterized as having a "short attention span." INTERVENTION: None. MAIN OUTCOME MEASURES: Standardized tests of arithmetic and reading supplemented by an assessment of calculation and quantitative skills. While performing calculations, fMRI disclosed predominantly left hemisphere activation involving the frontal and posterior parietal regions, whereas this task produced bilateral activation of the supramarginal gyrus in seven of nine normal subjects. RESULTS: Neuropsychological findings confirmed the presence of dyscalculia and dyslexia despite normal intellectual functioning. Visuospatial skills ranged from the low normal to average level. The fMRI findings were consistent with early interhemispheric transfer of visuospatial skills normally committed to the right parietal area to the left parietal region. The patient's dyscalculia and reading ability raise a question of acquired left parietal dysfunction as a consequence of the competition between verbal and visuospatial functions for left hemisphere representation. CONCLUSION: Interhemispheric reorganization of function may be bidirectional rather than a feature unique to the left hemisphere substrate for language.

Adolescent↗
PubMed1996

Posttraumatic Amnesia as a predictor of outcome after severe closed head injury. Prospective assessment.

OBJECTIVES: To identify the demographic and clinical variables related to the duration of posttraumatic amnesia after severe closed head injury; to evaluate the usefulness of posttraumatic amnesia duration in predicting outcome at the time of hospital discharge and at 6 months after injury. SETTING: Four clinical centers located in primary care hospitals. PATIENTS: Three hundred fourteen severely injured subjects aged 16 years or older who did not have trauma as a result of a penetrating injury and came out of coma before hospital discharge. INTERVENTIONS: Approximately half of the subjects were administered phenytoin sodium for some period after termination of coma; 17% were administered dexamethasone and 41% morphine sulfate. MAIN OUTCOME MEASURES: Galveston Orientation and Amnesia Test scores defined the duration of posttraumatic amnesia. The Glasgow Outcome Scale was used to grade outcome at the time of hospital discharge and at 6 months. RESULTS: Older age, low initial Glasgow Coma Scale score, nonreactive pupil(s), coma duration, and use of phenytoin were associated with a longer duration of posttraumatic amnesia. Poor pupillary response, time in coma, and duration of posttraumatic amnesia and use of phenytoin was predictive of the 6-month outcome. CONCLUSIONS: The results support the prognostic usefulness of prospectively measuring duration of posttraumatic amnesia after termination of coma. Pending replication, our findings suggest that posttraumatic amnesia duration may be a useful surrogate outcome measure for clinical trials involving interventions for acute head injury.

Adult↗
PubMed1996

Subacute methylphenidate treatment for moderate to moderately severe traumatic brain injury: a preliminary double-blind placebo-controlled study.

OBJECTIVE: To determine the effect of subacute administration of methylphenidate on recovery from moderate to moderately severe closed head injury. DESIGN: Double-blind placebo-controlled with random assignment. Patients were enrolled when their Galveston Orientation and Amnesia Test score was at least 65. Drug/placebo treatment began the day following baseline cognitive assessment and continued for 30 consecutive days. Follow-up evaluations were conducted at 30 and 90 days after baseline, after discontinuation of drug/placebo. SETTING: A level I trauma center. PATIENTS: Twenty-three patients ranging in age from 16 to 64 years. Head injury severity ranged from moderately severe (Glasgow Coma Score [GCS] < or = 8, no intracranial pressure monitor) to "complicated mild" (GCS from 13 to 15 with positive computed tomography brain scan). Thirty-day follow-up was based on 12 patients, whereas 90-day evaluation was based on 9 patients, with complicated mild head injuries excluded from the analyses. INTERVENTIONS: Methylphenidate administered twice daily at a dose of .30 mg/kg; placebo administered according to the same schedule in identical pill form. MAIN OUTCOME MEASURES: The Disability Rating Scale (DRS) and tests of attention, memory, and vigilance. RESULTS: The methylphenidate group was significantly better at 30 days on the DRS (p < .02), and on tests of attention (p < .03) and motor performance (p, .05). No significant differences were noted between groups at 90 days. CONCLUSIONS: Subacute administration of methylphenidate after moderately severe head injury appeared to enhance the rate but not the ultimate level of recovery as measured by the DRS and tests of vigilance. Problems with possible selection bias and small sample size limit generalization of results.

Adolescent↗
PubMed1996

Intraoperative evaluation of renal cell carcinoma: a prospective study of the role of ultrasonography and histopathological frozen sections.

PURPOSE: Nephron sparing surgery is being performed increasingly for treatment of renal cell carcinoma, including in select patients with a normal contralateral kidney. The number of tumors in the involved kidney (single versus multiple) and presence or absence of perinephric fat involvement (pathological stage T1 to 2 versus T3A) are important prognostic factors. In a prospective study we evaluated the accuracy of intraoperative histopathological frozen section analysis of renal capsular biopsies for assessing local tumor stage, and the accuracy of intraoperative ultrasonography for assessing tumor focality. MATERIALS AND METHODS: Intraoperative frozen section biopsies and ultrasonography were compared with information obtained from preoperative computerized tomography (CT), intraoperative inspection of the kidney by the surgeon and permanent histopathological specimens. RESULTS: We evaluated 99 patients (102 kidneys) with localized sold renal masses undergoing either radical nephrectomy (48) or nephron sparing surgery (54). Final pathological analysis revealed 95 renal cell carcinomas (stage T3A in 24), 6 oncocytomas and 1 angiomyolipoma. Multiple tumors were detected in 18 of 102 kidneys overall. Frozen section analysis identified 87% of the stage T3A lesions with no false-positive results, compared to CT, which only identified 67%. Ultrasonography identified 14 of 18 multifocal tumors (78%) and was not more accurate than the combination of CT and intraoperative inspection. However, during nephron sparing surgery ultrasonography was useful to localize the intrarenal extent of tumors (17 cases). CONCLUSIONS: Our results clarify the role of intraoperative ultrasonography and frozen section analysis in patients undergoing nephron sparing surgery for renal cell carcinoma. Frozen section analysis may be useful in select patients with small peripheral tumors who are under consideration for elective nephron sparing surgery.

Carcinoma, Renal Cell↗
PubMed1996

Testicular cancer in association with developmental renal anomalies and hypospadias.

OBJECTIVES: To characterize the clinical, pathologic, and genetic aspects of patients with a previously undescribed phenotype of testicular germ cell tumors associated with renal hypoplasia or agenesis and urethral hypospadias. METHODS: Review of clinical and pathologic findings and genetic analysis of constitutional and tumor DNA for mutations of the Wilms' tumor suppressor gene (WT1). RESULTS: Clinical findings suggest that this phenotype is distinct from other syndromes associated with renal anomalies and that the associated testicular tumors are histologically and clinically similar to those that occur sporadically. No karyotypic abnormalities, loss of heterozygosity, or mutations in the zinc finger domains (exons 7-10) of WT1 were observed in 5 patients with this phenotype. CONCLUSIONS: The phenotype of testicular germ cell tumor, developmental renal anomalies, and urethral hypospadias constitutes a discrete syndrome caused by a gene distinct from WT1.

Adult↗
PubMed1996

Behavioral outcomes after pediatric closed head injury: relationships with age, severity, and lesion size.

This study investigated the behavioral outcomes and adaptive functioning of 138 children with mild to severe closed head injury in the 6- to 16-year age range. Each child was evaluated with the Personality Inventory for Children-Revised. A subset of this sample (n = 77) received the Vineland Adaptive Behavior Scales. Results revealed little evidence for group differences based on severity of closed head injury on scales associated with psychopathology on the Personality Inventory for Children-Revised. However, children with severe closed head injury were viewed as experiencing more difficulties than children with mild-moderate closed head injury on those components of the Personality Inventory for Children-Revised most closely associated with cognitive functions. In addition, on the Vineland Adaptive Behavior Scales, severely injured children had lower scores on the Communication and Socialization scales than children with mild-moderate injury. Relationships between the size of frontal and extrafrontal lesions from concurrent magnetic resonance imaging and behavioral outcomes were not apparent. This study suggests that outcome measures assessing adaptive behavior and cognitive functions are more sensitive to severity of closed head injury than parent-based scales of internalizing and externalizing psychopathology.

Adolescent↗
PubMed1995

Open pelvic lymph node dissection for prostate cancer: a reassessment.

OBJECTIVES: To provide a risk-to-benefit analysis of open staging pelvic lymph node dissection (PLND) for prostate cancer. METHODS: The medical records of all patients presenting with prostate cancer from July 1989 to April 1994 were reviewed. A total of 245 patients with clinically localized disease were selected to undergo radical retropubic prostatectomy (RRP) preceded by open PLND. Univariate and multivariate analyses were performed to evaluate the predictive value of the preoperative serum prostate-specific antigen (PSA) concentration, clinical stage, and Gleason score with regard to final nodal status. The cost and morbidity associated with PLND in the setting of RRP was also defined. RESULTS: Overall, only 16 patients (6.5%) had lymph node metastases. Lymph node involvement correlated significantly with elevated serum PSA values (P = 0.0001), high Gleason score (P = 0.0022), and advanced clinical stage (P = 0.0001). Lymph node metastases were particularly uncommon in patients with nonpalpable tumors (1 of 67 [1.5%]), PSA values less than 10 (2 of 154 [1.3%]), and Gleason score less than 6 (1 of 26 [3.8%]). Overall, 179 patients (73.1%) presented with at least one or more of these favorable characteristics, and only 4 (2.2%) had lymph node involvement. Complications related to the lymphadenectomy occurred in 10 patients (4.1%). The cost per metastasis diagnosed in patients with low-risk characteristics was approximatley $43,600. CONCLUSIONS: An open staging PLND may no longer be justified on a routine basis in patients undergoing radical retropubic prostatectomy.

Adenocarcinoma↗
PubMed1995

Neurobehavioral outcome of closed head injury: implications for clinical trials.

This review encompasses the neurobehavioral sequelae of moderate to severe closed head injury (CHI). Following a discussion of posttraumatic amnesia and its measurement, the paper discusses assessment of the global outcome of CHI using the Glasgow Outcome Scale. Domains of residual neurobehavioral sequelae that are reviewed include attention/information processing speed, memory, language, intellectual ability, executive functions, and motor speed. The contribution of behavioral disturbance and psychosocial maladjustment to overall outcome is reviewed, as is the impact on the family. Finally, the neurobehavioral outcome measures for clinical trials involving moderate to severe head-injured patients are presented. Caveats for completing clinical trials that involve assessment of neurobehavioral functioning are provided.

Adult↗
PubMed1995

Prediction of recovery from traumatic brain injury.

This paper encompasses the prediction of early and late recovery from traumatic brain injury (TBI). Predictors of the duration of coma and the utilization of posttraumatic amnesia duration to predict residual memory function are discussed. The issues surrounding prediction of long-term neurobehavioral recovery from TBI are considered, particularly the patient and clinical variables that are related to intellectual recovery. Findings from the NIH Traumatic Coma Data are reviewed pertaining to testability as a criterion for outcome. In addition to discussing the relationship of specific neurologic indices of TBI as predictors, the results obtained using a regression model are summarized. Finally, the relationship of neuroimaging findings to neurobehavioral outcome is discussed including directions for future research.

Brain Injuries↗
PubMed1995

Frontal lobe changes after severe diffuse closed head injury in children: a volumetric study of magnetic resonance imaging.

In view of the pathophysiology and biomechanics of severe closed head injury (CHI) in children, we postulated that the frontal lobes sustain diffuse injury, even in the absence of focal brain lesions detected by magnetic resonance imaging (MRI). This study quantitated the morphological effects of CHI on the frontal lobes in children who sustained head trauma of varying severity. The MRI findings of 14 children who had sustained severe CHIs (Glasgow Coma Scale score of < or = 8) were compared with the findings in a matched group of 14 children having sustained mild head injuries (Glasgow Coma Scale score of 13-15). The patients ranged in age from 5 to 15 years at the time of their MRIs, which were acquired at least 3 months postinjury. MRI findings revealed no focal areas of abnormal signal in the frontal lobes. Volumetric analysis disclosed that the total prefrontal cerebrospinal fluid increased and the gray matter volume decreased in the patients with severe CHI, relative to the mildly injured comparison group. Gray matter volume was also reduced in the orbitofrontal and dorsolateral regions of the brains of children with severe CHI, relative to the children who sustained mild head trauma. These volumetric findings indicate that prefrontal tissue loss occurs after severe CHI in children, even in the absence of focal brain lesions in this area. Nearly two-thirds of the children who sustained severe CHIs were moderately disabled after an average postinjury interval of 3 years or more, whereas 12 of the 14 patients with mild CHIs attained a good recovery (2 were moderately disabled) by the time of study.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Sleep apnea and vigilance performance in a community-dwelling older sample.

Impaired vigilance performance has been reported in older subjects with sleep apnea syndrome (SAS). The current study is an attempt to extend these findings and to investigate additional factors that might have implications for vigilance in the older adult. Fifty-nine older adults [age: 62 +/- 5 (mean +/- SD), range 54-75 years; respiratory disturbance index (RDI): 8.8 +/- 14.4 (mean +/- SD), range 0-67.5] were categorized as SAS or NotSAS, based on various classification criteria [i.e. apnea index (AI) > or = 5, and 10, RDI > or = 5, 10 and 15], and were compared on their vigilance performance as assessed by the computer program "Steer Clear". Vigilance performance did not discriminate the groups, independent of how they were formed. Groups were then formed based on vigilance performance (HiVig vs. LowVig) and compared on assorted sleep variables, periodic leg movements, and self-reported hypersomnolence and depression. Only age discriminated vigilance performance (an inverse relationship), accounting for 31% of the observed variance. Our findings suggest that subject selection may unintentionally bias findings regarding the neuropsychological functioning of individuals with SAS, that vigilance may be impaired only in relatively more "severe" SAS, and that severity of SAS in older adults may not be well characterized by current classification standards. Age clearly impacted vigilance performance, despite the constricted age range sampled, and should be taken into account in future research.

Age Factors↗
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↗