Deborah D. Roman

Neuropsychological effects of cranial radiation: current knowledge and future directions

Radiation is an invaluable therapeutic tool in the treatment of cancer, with well-established palliative and curative efficacy. As patient survival has improved, attention has focused on long-range treatment side effects. One such adverse effect, neuropsychological impairment, is incompletely understood. Much of the extant research has been directed at childhood leukemia survivors treated with low-dose whole-brain radiation. Less is known about the effects of high-dose focal or whole-brain radiation used in the treatment of brain lesions. This article reviews the scientific literature in this area, with greatest emphasis on methodologically rigorous studies. Research design considerations are discussed. Review findings suggest that low-dose whole-brain radiation (18 to 24 Gy) in children is associated with mild delayed IQ decline, with more substantial deficits occurring in children treated at a young age. A high incidence of learning disabilities and academic failure is observed in this population and may be caused by poor attention and memory rather than low intellectual level. Children who receive higher dose radiation for treatment of brain tumors experience more pronounced cognitive decline. At higher doses, whole-brain radiation, in particular, is linked to deleterious cognitive outcomes. Remarkably little is known about cognitive outcomes in irradiated adults. Preliminary findings indicate that certain cognitive functions, including memory, may be more vulnerable to decline than others. Suggestions for future research are proposed.

Twenty-two nondirected kidney donors: An update on a single center's experience

At the University of Minnesota, we have defined ‘nondirected donation’ as organ donation by a volunteer who offered to donate an organ to anyone on the cadaver waiting list. From October 1, 1997, through October 31, 2003, we have had 360 inquiries about nondirected donation, have completed 42 detailed nondirected donor (NDD) evaluations for kidney donation, and have performed 22 NDD transplants. We herein review our program policies and how they have evolved, describe our evaluation and the motivation of our potential donors, summarize the outcome of NDD transplants, and raise issues requiring further attention and study. Our experience continues to support nondirected donation for kidney transplants.

Memory improvement following cardiac transplantation

Seventeen patients with severe cardiomyopathy underwent neuropsychological evaluation prior to and at least 1 year after successful heart transplantation. Study candidates were screened, and individuals with a history of stroke, cardiac arrest, or medical and neurological conditions which might affect brain function were excluded. Pre-transplant testing revealed normal intelligence and normal attentional, language, and executive abilities but impaired recent memory. Following heart transplant, memory functioning improved significantly, reaching normal levels. Other cognitive abilities remained unchanged. Results suggest that cardiomyopathy is associated with mesial temporal dysfunction, possibly attributable to inadequate or reduced cerebral blood flow and related hypometabolism. This cerebral dysfunction is potentially reversible following successful transplantation, which restores cardiac output and cerebrovascular perfusion.

Extended norms for the paced auditory serial addition task

Abstract The Paced Auditory Serial Addition Task (PASAT) and an abbreviated version of the WAIS-R were administered to 143 normal individuals, including 62 persons aged 18 to 27 (58% female), 40 aged 33 to 50 (50% female), and 41 aged 60 to 75 (51% female). PASAT means and standard deviations are presented. Analysis of variance results revealed significant age effects on PASAT performance, with the 60-to 75-year age group scoring significantly lower than the two younger age groups on all four PASAT series. No significant gender effect was found. Small but statistically significant correlations were found between PASAT performance and estimated IQ.

Predictors of postoperative memory function after left anterior temporal lobectomy

Patients who undergo left anterior temporal lobectomy (ATL) for intractable epilepsy are at risk of postoperative memory decline. This study attempts to identify the best predictors of memory after ATL using preoperative tests. Thirty-two consecutive patients who underwent left ATL with preoperative and postoperative neuropsychological testing were retrospectively identified. The following independent variables were analyzed by multiple regression: age of onset of seizures, age of temporal lobe damage, gender, MRI results, preoperative memory testing, and intracarotid amytal procedure (IAP) results. Neuropsychological measures of verbal and nonverbal memory served as dependent variables. Male gender (P<0.005), failing the IAP with both left and right hemispheres (P<0.001), and higher logical memory (LM) scores preoperatively (P<0.001) were associated with greater declines in LM after surgery. Our data demonstrate that the IAP predicts postoperative memory independent of other factors known to affect memory after left ATL.

Presurgical epilepsy localization with interictal cerebral dysfunction

Localization of interictal cerebral dysfunction with 2-[(18)F]fluoro-2-D-deoxyglucose (FDG) positron emission tomography (PET) and neuropsychological examination usefully supplements electroencephalography (EEG) and brain magnetic resonance imaging (MRI) in planning epilepsy surgery. In MRI-negative mesial temporal lobe epilepsy, correlation of temporal lobe hypometabolism with extracranial ictal EEG can support resection without prior intracranial EEG monitoring. In refractory localization-related epilepsies, hypometabolic sites may supplement other data in hypothesizing likely ictal onset zones in order to intracranial electrodes for ictal recording. Prognostication of postoperative seizure freedom with FDG PET appears to have greater positive than negative predictive value. Neuropsychological evaluation is critical to evaluating the potential benefit of epilepsy surgery. Cortical deficits measured with neuropsychometry are limited in lateralizing and localizing value for determination of ictal onset sites, however. Left temporal resection risks iatrogenic verbal memory deficits and dysnomia, and neuropsychological findings are useful in predicting those at greatest risk. Prognostication of cognitive risks with resection at other sites is less satisfactory.

Evaluating MMPI Validity in a Forensic Psychiatric Population Distinguishing between Malingering and Genuine Psychopathology

The MMPI scores of 353 forensic psychiatric patients were examined to determine the validity scale characteristics of this population. Frequency distributions are provided for L, F, K, F-K, and O-S. These findings suggest that traditional cutoffs for these scales are of questionable use in determining the validity of MMPI scores for this population. It is suggested that elevations on validity measures in this population may be due to characterological features, substance abuse, and the presence of acute psychopathology in addition to deliberate efforts to deceive. The validity and clinical scale characteristics of a small group of identified malingerers (n = 10) were compared to those of psychotic patients and were found to be distinctly different. Malingerers scored significantly higher on all “fake bad” validity measures (F, F-K, and O-S) and all clinical scales except 5 and 9, and lower on L and K. The clinical implications of these findings are discussed.

Memory performance on the intracarotid amobarbital procedure as a predicator of seizure focus.

The intracarotid amobarbital procedure (IAP) was performed on 56 patients with intractable complex-partial epilepsy who were candidates for temporal lobectomy. Seizure focus was lateralized to one hemisphere, as determined by surface EEG recordings and MRI evidence of temporal lobe disease. IAP memory items were presented following injection of 125 mg of sodium amytal into the internal carotid artery. Verbal, Nonverbal, Design, Pictorial, and Total memory scores were calculated based on recall/recognition of memory stimuli following drug recovery. Poorer memory was observed in the hemisphere ipsilateral to seizure focus on all memory scores. The Total Memory Score was the best memory measure, correctly classifying the largest number of patients. Using optimal cut-off scores on this measure, 75% of the patients with left hemisphere seizure focus and 79% of the patients with right seizure focus were correctly classified. There was a definite tendency for the dominant hemisphere to outperform the non-dominant. This must be taken into account in arriving at optimal cut-off points.

The mentally disordered criminal offender: A description based on demographic, clinical, and MMPI data

From 340 MMPIs of male forensic state hospital patients, seven disjoint clusters were obtained by an innovative cluster strategy that combined Wards hierarchical clustering with a partitioning method. The cluster groups differed on racial composition and DSM-III Axis II diagnoses. The lack of differences among the cluster groups on other clinically relevant variables may be due to the choice of measures and the homogeneous nature of the sample. Two-point code frequencies are presented for these 340 profiles. Demographic variables available on 434 subjects suggested considerable similarities between this group and prison populations. The analysis further suggested that factors such as sociopathy, substance abuse, psychosis with paranoid features, and a history of criminal activities distinguish these offenders from the benign mentally ill.

Efficacy of the Continuous Visual Memory Test in Lateralizing Temporal Lobe Dysfunction in Chronic Complex-Partial Epilepsy

The Continuous Visual Memory Test (CVMT) was hypothesized to measure nondominant temporal lobe dysfunction in patients with refractory complex-partial epilepsy. Thirty-seven temporal lobectomy candidates, of whom 20 had a right temporal seizure focus (RT) and 17 had a left temporal seizure focus (LT), were selected for study. Contrary to the hypothesis, initial results indicated that the LT group performed below the RT group for both the CVMT Total score and the Delayed Recognition score; however, group differences disappeared after accounting for Full Scale IQ scores. Both CVMT scores correlated positively and significantly with Full Scale IQ, Block Design, and the Meier Visual Discrimination Test, suggesting that overall cognitive functioning and visual-perceptual processing are positively related to CVMT performance. These results are consistent with other recent findings which suggest that extant nonverbal memory tests may be inadequate in lateralizing nondominant hemisphere lesions in complex-partial epilepsy.