Implications from neurologic assessment of brain protection for total arch replacement from a randomized trial.

OBJECTIVE: The study objective was to perform a randomized trial of brain protection during total aortic arch replacement and identify the best way to assess brain injury. METHODS: From June 2003 to January 2010, 121 evaluable patients were randomized to retrograde (n = 60) or antegrade (n = 61) brain perfusion during hypothermic circulatory arrest. We assessed the sensitivity of clinical neurologic evaluation, brain imaging, and neurocognitive testing performed preoperatively and 4 to 6 months postoperatively to detect brain injury. RESULTS: A total of 29 patients (24%) experienced neurologic events. Clinical stroke was evident in 1 patient (0.8%), and visual changes were evident in 2 patients; all had brain imaging changes. A total of 14 of 95 patients (15%) undergoing both preoperative and postoperative brain imaging had evidence of new white or gray matter changes; 10 of the 14 patients had neurocognitive testing, but only 2 patients experienced decline. A total of 17 of 96 patients (18%) undergoing both preoperative and postoperative neurocognitive testing manifested declines of 2 or more reliable change indexes; of these 17, 11 had neither imaging changes nor clinical events. Thirty-day mortality was 0.8% (1/121), with no neurologic deaths and a similar prevalence of neurologic events after retrograde and antegrade brain perfusion (22/60, 37% and 15/61, 25%, respectively; P = .2). CONCLUSIONS: Although this randomized clinical trial revealed similar neurologic outcomes after retrograde or antegrade brain perfusion for total aortic arch replacement, clinical examination for postprocedural neurologic events is insensitive, brain imaging detects more events, and neurocognitive testing detects even more. Future neurologic assessments for cardiovascular procedures should include not only clinical examination but also brain imaging studies, neurocognitive testing, and long-term assessment.

Memory performance in older adults before and after temporal lobectomy for pharmacoresistant epilepsy.

Little is known about the effects of epilepsy surgery on memory in older adults. The purpose of this study was to determine if older adults exhibit greater memory decline than younger adults after anterior temporal lobectomy (ATL). Patients 55 years and older at time of surgery (23 left, 14 right ATL, range 55-66 years) were compared to patients age 25-35 years (44 left, 33 right ATL) to assess differences in preoperative to postoperative change in WMS-III index scores. Repeated-measures ANOVAs and ANCOVAs revealed that older patients did not demonstrate greater decline than younger patients across any of the memory indices. Rather, in the left ATL group, older patients showed less decline than younger patients on the Auditory Delayed Memory Index. Similarly, in the right ATL group, older patients showed less decline than younger patients on the Visual Delayed Memory Index. These patterns were also apparent in frequency of individual change. Results provide preliminary evidence that older adults who are good candidates for ATL are not at greater risk for memory decline when measured at 7 months postoperatively.

Pre-surgical mood predicts memory decline after anterior temporal lobe resection for epilepsy.

This study examined pre-surgical depressed mood as a predictor of post-surgical memory change in adults who underwent temporal lobe resections (TLRs; n = 211). Patients completed the Wechsler Memory Scale-III and Beck Depression Inventory-Second Edition (BDI-II) before and after TLR (left = 110, right = 101) and were divided into two groups (clinically elevated depressive symptoms or not depressed) based on BDI-II score. Left-TLR patients with poorer pre-surgical mood had greater verbal memory declines after surgery compared with nondepressed left- or right-TLR patients and right-TLR patients with poor mood. Further, pre-surgical BDI-II score demonstrated incremental validity in predicting post-surgical memory change in left-TLR patients beyond pre-surgical memory scores. Differences in seizure outcome and post-surgical mood change could not account for memory decline. Results suggest that elevated pre-surgical depressive symptomatology is a risk factor for post-surgical memory decline and indicate that mood should be considered when advising patients about cognitive risks associated with temporal lobectomy. Results are discussed in terms of poor pre-surgical mood as an indicator of reduced cognitive reserve.

The Family Pictures subtest of the WMS-III: relationship to verbal and visual memory following temporal lobectomy for intractable epilepsy.

This study examined the extent to which the Family Pictures (FP) subtest of the Wechsler Memory Scale-Third Edition (WMS-III) is related to verbal memory measures and right mesial temporal integrity. Epilepsy patients who underwent temporal lobectomy did not differ in the extent to which FP scores changed from before to after surgery, although postoperative FP performance was worse in those who underwent right temporal lobectomy than in those who underwent left temporal lobectomy. FP was most strongly related to the Logical Memory subtest from the WMS-III. Results suggest that FP measures both verbal and visual memory and is minimally sensitive to lateralization of temporal lobectomy.

Poor presurgical performance on both verbal and visual memory measures is associated with low risk for memory decline following left temporal lobectomy for intractable epilepsy.

Studies have shown a lower risk for verbal memory decline following dominant anterior temporal lobectomy (ATL) among patients with poor, presurgical verbal memory scores. It is unclear however, if the risk of decline is increased in patients who also have reduced visual memory. Objective and subjective memory outcome following left ATL was examined in twelve patients with reduced presurgical visual and verbal memory scores. Only one patient demonstrated a meaningful decline in memory scores, with a decline in visual memory following surgery. Presurgically, this patient demonstrated poor memory bilaterally on Wada testing and small discrepancy in hippocampal volumes. She was also one of two patients who continued to have seizures post-surgery. This preliminary study suggests that patients with unilateral, left TLE and poor verbal and visual memory are unlikely to show meaningful memory declines following left ATL, particularly if they demonstrate expected patterns on Wada testing, hippocampal volume discrepancy (left < right), and postsurgical seizure-freedom.

Relationship between presurgical memory performance on the Wechsler Memory Scale-III and memory change following temporal resection for treatment of intractable epilepsy.

Previous research demonstrated a relationship between preoperative memory measured by the Wechsler Memory Scale-Revised (WMS-R) and postsurgical memory change in patients who underwent left (LATL), but not right (RATL) anterior temporal lobectomy. The current study replicated previous efforts using the Wechsler Memory Scale-Third Edition (WMS-III) in a larger sample. The WMS-III was administered to 161 patients with medically intractable epilepsy prior to and approximately 6 months following LATL or RATL. Correlations between presurgical memory on WMS-III indices and memory change following surgery were calculated for each group. Significant negative relationships were found between pre- and postsurgical memory scores in patients who underwent LATL on all WMS-III measures (r=-0.31 to -0.43). Significant negative correlations were observed in patients who underwent RATL only on visual memory measures (r=-0.24 to -0.44). Findings support previous conclusions using the WMS-R showing that patients who undergo LATL with higher presurgical memory ability are at greater risk for memory decline following temporal resection than patients with lower presurgical memory scores.

Evaluating the contributions of state-of-the-art assessment techniques to predicting memory outcome after unilateral anterior temporal lobectomy.

PURPOSE: Although anterior temporal lobectomy (ATL) is an effective treatment for many patients with medically refractory temporal lobe epilepsy (TLE), one risk associated with this procedure is postsurgical decline in memory. A substantial number of past studies examined factors that predict memory decline after surgery, but few have investigated multiple predictors simultaneously or considered measures that are currently in use. METHODS: This study compared the relative contributions made by presurgical neuropsychological test scores, MRI-based hippocampal volumetric analysis, and Wada test results to predicting memory outcome after ATL in a group of 87 patients. RESULTS: Logistic regression analyses indicated that noninvasive procedures (neuropsychological testing and MRI) made significant contributions to improving the prediction of memory outcome in this sample. The results from the Wada procedure did not significantly improve prediction once these other factors were considered. The only exception was in predicting memory for visual information after a delay, in which Wada results improved prediction accuracy from 78% to 81%. CONCLUSIONS: Current neuropsychological tests and MRI volumetric measures predict changes in verbal and visual memory after ATL. The relatively small change in correct classification rates when Wada memory scores are considered calls into question the benefits of using Wada test results to predict memory outcome when the results of noninvasive procedures are available.

Magnesium as a neuroprotectant in cardiac surgery: a randomized clinical trial.

OBJECTIVE: We sought to evaluate magnesium as a neuroprotectant in patients undergoing cardiac surgery with cardiopulmonary bypass. METHODS: From February 2002 to September 2003, 350 patients undergoing elective coronary artery bypass grafting, valve surgery, or both were enrolled in a randomized, blinded, placebo-controlled trial to receive either magnesium sulfate to increase plasma levels 1(1/2) to 2 times normal during cardiopulmonary bypass (n = 174) or no intervention (n = 176). Neurologic function, neuropsychologic function, and depression were assessed preoperatively, at 24 and 96 hours after extubation (neurologic) and at 3 months (neuropsychologic, depression). Neurologic scores were analyzed using ordinal longitudinal methods, and neuropsychologic and depression inventory data were summarized by principal component analysis, followed by linear regression analysis using component scores as response variables. RESULTS: Seven (2%) patients had a postoperative stroke, 2 (1%) in the magnesium and 5 (3%) in the placebo group (P = .4). Neurologic score was worse postoperatively in both groups (P < .0001); however, magnesium group patients performed better than placebo group patients (P = .0001), who had prolonged declines in short-term memory and reemergence of primitive reflexes. Three-month neuropsychologic performance and depression inventory score were generally better than preoperatively, with few differences between groups (P > .6); however, older age (P = .0006), previous stroke (P = .003), and lower education level (P = .0007) were associated with worse performance. CONCLUSIONS: Magnesium administration is safe and improves short-term postoperative neurologic function after cardiac surgery, particularly in preserving short-term memory and cortical control over brainstem functions. However, by 3 months, other factors and not administration of magnesium influence neuropsychologic and depression inventory performance.

Patients' perceptions of memory functioning before and after surgical intervention to treat medically refractory epilepsy.

PURPOSE: One risk associated with epilepsy surgery is memory loss, but perhaps more important is how patients perceive changes in their memories. This longitudinal study evaluated changes in memory self-reports and investigated how self-reports relate to changes on objective memory measures in temporal or extratemporal epilepsy patients who underwent surgery. METHODS: Objective memory (Wechsler Memory Scale-Revised) and subjective memory self-reports (Memory Assessment Clinics Self-Rating Scale) were individually assessed for 136 patients approximately 6 months before and 6 months after surgery. A measure of depressive affect (Beck Depression Inventory-2nd Edition) was used to control variance attributable to emotional distress. RESULTS: Despite a lack of significant correlational relationships between objective and subjective memory for the entire sample, significant correlations between objective memory scores and self-reports did emerge for a subset of patients who evidenced memory decline. Differences also were found in the subjective memory ratings of temporal lobe versus extratemporal patients. Temporal lobe patients rated their memories more negatively than did extratemporal patients and were more likely to report significant improvements in their memory after surgery. CONCLUSIONS: In general, patients were not accurate when rating their memories compared to other adults. However, patients with significant declines in their memories were sensitive to actual changes in their memories over time relative to their own personal baselines.