Significant Postoperative Decline Research Articles

98 Cognitive Outcomes Following Bilateral Focused Ultrasound Thalamotomy for Tremor

Objective:Essential tremor (ET) is the most common movement disorder, characterized by bilateral action tremors of the upper extremities. Surgical interventions can be considered for severe cases that are refractory to medication. Magnetic resonance-guided focused ultrasound (MRgFUS) of the ventral intermediate nucleus of the thalamus (Vim) is a recently approved, minimally invasive treatment for unilateral tremor. While patients are generally pleased with unilateral treatment, many patients are bothered by tremor on the untreated side. Historically, bilateral thalamotomy has been associated with a higher rate of adverse events, including cognitive impairment. MRgFUS Vim thalamotomy for bilateral tremor is currently being investigated. The goal of the present study was to evaluate the effect of bilateral MRgFUS Vim thalamotomy on cognition.Participants and Methods:Twelve patients with medication-refractory essential tremor (mean age = 68.77 +/- 11.78 years, mean education = 14.34 +/- 2.71 years, 8 male) were included in the present study. Three of the 12 patients met criteria for mild cognitive impairment (MCI). All patients successfully underwent unilateral MRgFUS thalamotomy at least 48 weeks before the second thalamotomy. A battery of neuropsychological tests was administered to patients before (considered baseline in the present study) and three months following the second thalamotomy. Baseline evaluations occurred on average 144.64 +/- 91.53 weeks (range: 55.00 - 346.58) after the first thalamotomy. The neuropsychological battery assessed domains of processing speed (Oral Symbol Digit Modalities Test, D-KEFS Color-Word Naming and Reading), attention (WAIS-IV Digit Span Forward), executive function (D-KEFS Color-Word Inhibition and Inhibition/Switching), working memory (WAIS-IV Digit Span Backward and Sequencing), verbal fluency (D-KEFS Letter Fluency and Animal Fluency), confrontation naming (Boston Naming Test), verbal memory (Hopkins Verbal Learning Test-Revised), and visuospatial perception (Judgment of Line Orientation). Alternate versions of tests were used when possible. Cognitive changes were analyzed at the group and individual level. Group level changes were assessed with paired sample t-tests (corrected for multiple comparisons). At the individual level, postoperative declines > 1.5 SD from baseline were considered clinically significant.Results:Participants’ baseline intellectual functioning ranged from low average to superior (as measured by the WTAR). The mean baseline score on the Montreal Cognitive Assessment was 24.58 (range: 17 - 30). At the group level, there were no significant changes in cognitive scores from baseline to follow-up (all p values > 0.635). At the individual level, one patient with MCI declined > 1.5 SD on the verbal memory composite. No other patients showed declines > 1.5 SD.Conclusions:Our preliminary findings suggest that bilateral MRgFUS Vim thalamotomy is relatively safe from a cognitive perspective. However, a single patient with MCI exhibited clinically significant postoperative decline in verbal memory. Future studies with larger sample sizes are needed to investigate the factors that increase the risk of postoperative cognitive decline, including pre-existing cognitive impairment, older age, and lesion size.

Functional outcome and frailty in colorectal surgery patients.

Frailty is a recognized risk and predictor of poor health outcomes in older patients undergoing surgery. A significant proportion of elderly patients undergoing colorectal cancer-related surgery are nevertheless not routinely assessed for frailty in current clinical practice in Australia. We examined the preoperative use of the Clinical Frailty Scale (CFS) to predict post-operative functional outcomes in geriatric patients undergoing colorectal cancer surgery. This retrospective observational cohort study included elderly colorectal cancer patients (n = 227) who underwent elective major colorectal surgery from 2016 to 2020 at Nepean Hospital, Australia. CFS was calculated retrospectively from medical records and the relationship between CFS and functional outcome factors was analysed. Frail patients (n = 111) had a significant postoperative functional decline as demonstrated by discharge to supported care (57% vs. 0.9%), Barthel Index change (P<0.05) and inability to self-manage stoma (P<0.05) compared to non-frail patients (n = 116). Multivariate analysis with adjustment for age, comorbidities as measured by Charlson Comorbidities Index (CCI), and cognitive impairment, demonstrated frailty was the most significant independent predictor of discharge to supported care (OR 109.3). Cognitive impairment and an increased CCI were also found to be important predictors. Preoperative frailty is significantly associated with postoperative functional decline and postoperative adverse outcomes, highlighting the potential utility of CFS in preoperative frailty assessment.

One-year neuropsychological outcome after temporal lobe epilepsy surgery in large Czech sample: Search for factors contributing to memory decline.

Background: Assessment of cognitive functions is an integral part of the evaluation the efficacy of temporal resections. We studied postoperative neuropsychological changes and factors contributing to worse memory outcomes in patients who experienced a significant decline using reliable change indices.Methods: We prospectively studied 110 patients in whom we indicated anteromesial temporal resection (AMTR) and 46 patients who underwent selective amygdalohippocampectomy (SAHE). We administrated Wechsler Adult Intelligence Scale-Revised, Wechsler Memory Scale-Revised, and the Verbal Fluency Test before and 1 year after the operation.Results: At a group level, we did not observe any statistically significant changes in global, verbal, and visual MQ in either the AMTR or the SAHE group. At an individual level, we found a mean decrease of verbal MQ after left-sided AMTR by −4.43 points (P = 0.01). We detected no significant differences between the left and right side of surgery in the SAHE group. In patients with significant postoperative memory decline, we found either pre-existing extrahippocampal deficits/postoperative complications or incomplete hippocampal resection or a combination of these factors.Conclusion: In addition to the side of surgery, structural integrity and functional adequacy of resected hippocampus and volume of resected tissue and preoperative extrahippocampal lesions/postoperative complications also contribute to postoperative memory decline after temporal lobe epilepsy surgery.

Comparison of Montreal cognitive assessment and Mattis dementia rating scale in the preoperative evaluation of subthalamic stimulation in Parkinson's disease.

IntroductionThe preoperative evaluation of Parkinson’s Disease (PD) patients for subthalamic nucleus deep brain stimulation (STN-DBS) includes the assessment of the neuropsychological status of the patient. A widely used preoperative test is the Mattis Dementia rating scale (MDRS). However, the Montreal cognitive assessment (MoCA) has also been proven to be a sensitive, time-sparing tool with high diagnostic validity in PD. We evaluate the utility of the MoCA as a preoperative screening test for PD patients undergoing bilateral STN-DBS.MethodsIn this single-centre, retrospective study, we analysed pre- and postoperative assessments of MoCA, MDRS, Movement disorder society-Unified PD Rating Scale-motor examination, PD Questionnaire-39 and levodopa equivalent daily dose. Longitudinal outcome changes were analysed using paired t-test, Pearson’s correlation coefficient, linear regression and CHAID (chi-square automatic interaction detector) regression tree model.ResultsClinical motor and cognitive scores of 59 patients (61.05±7.73 years, 24 females) were analysed. The MoCA, but not the MDRS, identified significant postoperative cognitive decline in PD patients undergoing STN-DBS. The preoperative MoCA score correlated with postoperative quality of life improvement, whereas the MDRS did not. PD patients with a MoCA score ≤ 23 points had a significant decline of quality of life after DBS surgery compared to patients > 23 points.ConclusionThis study identifies the MoCA as an alternative test within the preoperative evaluation of PD patients for the detection of neuropsychological deficits and prediction of the postoperative improvement of quality of life.

CNTM-04. Alterations in structural connectomic properties associated with neurocognitive changes following glioma resection

Abstract BACKGROUND Patients with brain tumors often experience decline in neurocognitive functioning (NCF) following surgical tumor resection. Connectomic studies have begun to uncover how abnormalities to underlying cerebral networks contribute to NCF deficits; however, few studies have investigated relationships between pre- to postoperative changes in structural connectomics and NCF. METHODS Fifteen right-handed adults with left perisylvian tumors underwent MRI of the brain with diffusion tensor imaging (DTI) and neuropsychological assessment before and after awake tumor resection. Graph theoretical analysis was applied to DTI-derived connectivity matrices to calculate structural network properties. Structural network properties and NCF measures were compared across the pre- to postoperative periods with matched pairs Wilcoxon signed-rank tests. Associations between pre- to postoperative change in network properties and change in NCF were determined with Spearman rank-order correlations (ρ). RESULTS Nearly 90% of the sample showed postoperative decline on 1 or more NCF measures. Significant postoperative NCF decline was found across measures of verbal memory, processing speed, executive functioning, receptive language, and the Clinical Trial Battery Composite (CTB COMP) index. Regarding connectomic properties, significant postoperative changes were observed in global and local efficiency, characteristic path length, clustering coefficient, betweenness centrality, and assortativity, with medium effect sizes. Significant associations (ρ = .59 to .62, all p &amp;lt; .05) were observed between changes in aspects of NCF and connectomic properties. CONCLUSIONS Decline in NCF was common following resection and some postoperative outcomes were associated with changes in structural connectomic properties following surgery.

Alterations in Functional Connectomics Associated With Neurocognitive Changes Following Glioma Resection.

Decline in neurocognitive functioning (NCF) often occurs following brain tumor resection. Functional connectomics have shown how neurologic insults disrupt cerebral networks underlying NCF, though studies involving patients with brain tumors are lacking. To investigate the impact of brain tumor resection upon the connectome and relationships with NCF outcome in the early postoperative period. A total of 15 right-handed adults with left perisylvian glioma underwent resting-state functional magnetic resonance imaging (rs-fMRI) and neuropsychological assessment before and after awake tumor resection. Graph theoretical analysis was applied to rs-fMRI connectivity matrices to calculate network properties. Network properties and NCF measures were compared across the pre- to postoperative periods with matched pairs Wilcoxon signed-rank tests. Associations between pre- to postoperative change in network and NCF measures were determined with Spearman rank-order correlations (ρ). A majority of the sample showed postoperative decline on 1 or more NCF measures. Significant postoperative NCF decline was found across measures of verbal memory, processing speed, executive functioning, receptive language, and a composite index. Regarding connectomic properties, betweenness centrality and assortativity were significantly smaller postoperatively, and reductions in these measures were associated with better NCF outcomes. Significant inverse associations (ρ = -.51 to -.78, all P<.05) were observed between change in language, executive functioning, and learning and memory, and alterations in segregation, centrality, and resilience network properties. Decline in NCF was common shortly following resection of glioma involving eloquent brain regions, most frequently in verbal learning/memory and executive functioning. Better postoperative outcomes accompanied reductions in centrality and resilience connectomic measures.

Neuropsychological Function and Quality of Life after Resection of Suspected Lower-Grade Glioma in the Face Primary Motor Area.

The negative side effects of neurosurgical resection of the lower third of the primary motor cortex (M1) are often described as relatively mild. However, detailed descriptions of how these resections affect neurocognitive function, speech, mental health and quality of life (QoL) are sparse. In the present study, seven patients with suspected lower-grade glioma (WHO II-III) in the inferior M1 were assessed for facial motor function, cognitive function, anxiety and QoL before and after awake surgical resections. The main finding was that after surgery, six of the seven patients experienced a mild facial motor dysfunction, mainly affecting the mouth, tongue and throat. At the group level, we were also able to observe a significant postoperative decline in maximum verbal speed, whereas no negative effects on measures of word production (i.e., verbal fluency) were seen. Self-reported QoL data suggest that some patients experienced increased social isolation postoperatively but do not lend support to the interpretation that this was caused by direct neurological side effects of the surgery. The results appear to support the general notion that awake surgery in the lower M1 can be performed safely and with postoperative deficits that are most often perceived by the patient as tolerable.

A study to compare short term postoperative cognitive outcomes in paediatric patients using intravenous propofol versus inhalational sevoflurane in maintenance of general anaesthesia

Postoperative cognitive dysfunction (POCD) is a newly diagnosed subtle impairment of memory, concentration, and speed of information processing after surgery. POCD in adults and geriatric population has been well established, but less explored in the paediatric age group. The aim of this study is to compare the effects of intravenous propofol and inhalational sevoflurane on short term postoperative cognitive outcomes in children. Experimental approach: 80 paediatric patients aged 5 - 15 years of ASA grade I and II posted for surgeries under general anaesthesia except neurosurgery were randomly allocated into two groups with 40 patients in each group. Group A received intravenous propofol and Group B received inhalational sevoflurane for maintenance of general anaesthesia. Cognitive assessment tests were done using Wechsler's Intelligence Scale for Children (WISC-V) both preoperatively and postoperatively at 6hr, 12hr and 24hr respectively. Major Findings: Comparison of various cognitive indices in Group A and B is significantly lower at 6 hours in comparison to the preoperative value. Comparison of various cognitive indices between preoperative and at 24 hours postoperative levels, in Group A and B showed that these parameters return to the preoperative state at 24 hours after surgery.Conclusion: There is no significant postoperative cognitive decline in patients comparing the cognitive functions preoperatively and 24 hour postoperative levels when using intravenous propofol versus inhalational sevoflurane. There was a transient but significant decline noted in the cognitive functions at 6 hour postoperatively compared to the preoperative period, noticed equally with both groups.

Needle Catheter Jejunostomy in Patients Undergoing Surgery for Upper Gastrointestinal and Pancreato-Biliary Cancer-Impact on Nutritional and Clinical Outcome in the Early and Late Postoperative Period.

The metabolic risk for patients undergoing abdominal cancer resection increases in the perioperative period and malnutrition may be observed. In order to prevent further weight loss, the guidelines recommend for high-risk patients the placement of a needle catheter jejunostomy (NCJ) for supplementing enteral feeding in the early and late postoperative period. Our aim was to evaluate the safety of NCJ placement and its potential benefits regarding the nutritional status in the postoperative course. We retrospectively analyzed patients undergoing surgery for upper gastrointestinal cancer, such as esophageal, gastric, and pancreato-biliary cancer, and NCJ placement during the operation. The nutritional parameters body mass index (BMI), perioperative weight loss, phase angle measured by bioelectrical impedance analysis (BIA) and the clinical outcome were assessed perioperatively and during follow-up visits 1 to 3 months and 4 to 6 months after surgery. In 102 patients a NCJ was placed between January 2006 and December 2016. Follow-up visits 1 to 3 months and 4 to 6 months after surgery were performed in 90 patients and 88 patients, respectively. No severe complications were seen after the NCJ placement. The supplementing enteral nutrition via NCJ did not improve the nutritional status of the patients postoperatively. There was a significant postoperative decline of weight and phase angle, especially in the first to third month after surgery, which could be stabilized until 4–6 months after surgery. Placement of NCJ is safe. In patients with upper gastrointestinal and pancreato-biliary cancer, supplementing enteral nutrition during the postoperative course and continued after discharge may attenuate unavoidable weight loss and a reduction of body cell mass within the first six months.

Comparative Effect of Local Anesthesia with Lidocaine 2% Versus Topical Anesthesia on Cognitive Function in Ophthalmic Surgery.

BackgroundMultiple clinical trials targeted the assessment of cognitive function following local versus general anesthesia in patients undergoing ophthalmic surgery, but no previous clinical trials have focused on the effect of topical anesthesia on cognitive function.ObjectivesThis study aimed to compare the effect of local anesthesia with lidocaine 2% versus topical anesthesia with Oxybuprocaine (benoxinate hydrochloride 0.4%) on cognitive function in patients undergoing elective cataract surgery.MethodsThis is a prospective randomized clinical trial carried out on 60 patients undergoing elective cataract surgery by phacoemulsification. Thirty patients received local anesthesia with lidocaine 2% and thirty patients received topical anesthesia with Oxybuprocaine (benoxinate hydrochloride 0.4%). Patients’ satisfaction was assessed postoperatively using the Iowa satisfaction with anesthesia scale (ISAS). Cognitive assessment for all patients was done preoperatively and 1 week postoperatively using paired-associate learning test (PALT) and category verbal fluency (VF) test (animal category).ResultsThere was no statistically significant difference between local and topical anesthesia groups in the mean of responses to the 11 statements of ISAS (P = 0.071). Regarding cognitive assessment, there was a statistically significant postoperative decline in the local anesthesia group in both PALT scores (P = 0.005) and VF scores (P = 0.01). In the topical anesthesia group, there was no statistically significant difference between pre- and postoperative PALT scores (P = 0.326) or VF scores (P = 0.199).ConclusionsPostoperative cognitive dysfunction following elective cataract surgeries under local anesthesia can be attributed to the effect of local anesthesia rather than the effect of surgery.

Postoperative memory prognosis in temporal lobe epilepsy surgery: The contribution of postictal memory.

The prediction of verbal memory decline after temporal lobe epilepsy (TLE) surgery remains difficult at an individual level. We evaluated the prognostic value of postictal memory testing in predicting the postoperative verbal memory function. Sixty-three consecutive patients were included in the analysis who underwent TLE surgery at our center with preoperative interictal/postictal and postoperative memory testing. Verbal memory was evaluated using the Rey Auditory Verbal Learning Test (RAVLT). We used reliable change indices with 90% confidence interval (90% RCIs) to evaluate a significant postoperative memory decline. The sensitivity (Sn), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), area under the curve (AUC), and accuracy (ACC) were calculated. The analysis was performed for all TLE patients and for the subgroup with hippocampal sclerosis (HS). Left-TLE patients (n=31) had lower verbal memory scores on RAVLT than right-TLE at 3months (57% vs 78%) and 12months (53% vs 78%) after surgery. The 90% RCI was estimated to be a loss of4 out of 15 items.The predictive value was Sn = 42%, Sp = 84%, PPV = 39%, NPV = 86%, AUC = 0.630, and ACC = 76% to predict a verbal memory decline in the whole group (n=63). In HS patients (n=41), the postictal verbal memory test had Sn = 50%, Sp = 88%, PPV = 50%, NPV = 88%, AUC = 0.689, and ACC = 81% to predict a significant postoperative decline. Postictal memory is a noninvasive bedside memory test that can help predict the postoperative verbal memory decline in patients with HS with an overall accuracy of 81%.

The impact of brain-derived neurotrophic factor Val66Met polymorphism on cognition and functional brain networks in patients with intractable partial epilepsy.

Medial temporal lobe epilepsy (mTLE) is the most common refractory focal epilepsy in adults. Around 30%-40% of patients have prominent memory impairment and experience significant postoperative memory and language decline after surgical treatment. BDNF Val66Met polymorphism has also been associated with cognition and variability in structural and functional hippocampal indices in healthy controls and some patient groups. We examined whether BDNF Val66Met variation was associated with cognitive impairment in mTLE. In this study, we investigated the association of Val66Met polymorphism with cognitive performance (n=276), postoperative cognitive change (n=126) and fMRI activation patterns during memory encoding and language paradigms in 2 groups of patients with mTLE (n=37 and 34). mTLE patients carrying the Met allele performed more poorly on memory tasks and showed reduced medial temporal lobe activation and reduced task-related deactivations within the default mode networks in both the fMRI memory and language tasks than Val/Val patients. Although cognitive impairment in epilepsy is the result of a complex interaction of factors, our results suggest a role of genetic factors on cognitive impairment in mTLE.

Longitudinal hippocampal and extra-hippocampal microstructural and macrostructural changes following temporal lobe epilepsy surgery

Objectives1) Characterize the evolution of microstructural changes in the contralateral, non-operated hippocampus—using longitudinal diffusion tensor imaging (DTI)—following surgery for temporal lobe epilepsy (TLE). 2) Characterize the downstream extra-hippocampal volumetric changes of the fornix and mammillary bodies after TLE surgery. 3) Examine the relationship between these measures and seizure/cognitive outcome. MethodsSerial structural and DTI brain MRI scans were collected in 25 TLE patients pre- and post-surgery (anterior temporal lobectomy, ATL – 13; selective amygdalohippocampectomy, SelAH – 12) and in 12 healthy controls. Contralateral hippocampal fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD) were computed with manual hippocampal tracings as volumes of interest following co-registration to anatomical images. Fornix and mammillary body volumetry was performed by manual segmentation. ResultsAfter surgery, the non-resected hippocampus showed significant postoperative decline in FA (p = 0.0001), with increase of MD (p = 0.01) and RD (p = 0.0001). In contrast to the timing of our previously reported volume changes where atrophy is observed in the first week, diffusion changes occurred late, taking 1–3 years to develop and are not significant at one week after surgery. Diffusion changes are accompanied by delayed limbic circuit volume loss in the mammillary bodies (35%; p < 0.0001) and fornix (24%; p < 0.0001) compared to baseline. There was no correlation between postoperative diffusion or structural changes and memory score nor did the degree of postoperative change in hippocampal DTI parameters, mammillary body volume or fornix volume vary significantly based on seizure outcome. SignificanceDifferences observed in the timing of postoperative volume (first week) and FA/MD (one year) changes would suggest that early contralateral hippocampal atrophy is not secondary to fluid shifts (dehydration) while the late DTI changes suggest ongoing microstructural changes extending beyond the early postoperative period. Postoperative hippocampal diffusion changes are accompanied by delayed mammillary body and fornix volume loss which did not differ when stratified by seizure outcome nor was correlated with degree of hippocampal diffusion change. Finally, we did not identify any significant correlation between postoperative diffusion parameter change and memory performance.

Predicting postoperative language outcome using presurgical fMRI, MEG, TMS, and high gamma ECoG

ObjectiveTo predict the postoperative language outcome using the support vector regression (SVR) and results of multimodal presurgical language mapping. MethodsEleven patients with epilepsy received presurgical language mapping using functional MRI (fMRI), magnetoencephalography (MEG), transcranial magnetic stimulation (TMS), and high-gamma electrocorticography (hgECoG), as well as pre- and postoperative neuropsychological evaluation of language. We constructed 15 (24–1) SVR models by considering the extent of resected language areas identified by all subsets of four modalities as input feature vector and the postoperative language outcome as output. We trained and cross-validated SVR models, and compared the cross-validation (CV) errors of all models for prediction of language outcome. ResultsSeven patients had some level of postoperative language decline and two of them had significant postoperative decline in naming. Some parts of language areas identified by four modalities were resected in these patients. We found that an SVR model consisting of fMRI, MEG, and hgECoG provided minimum CV error, although an SVR model consisting of fMRI and MEG was the optimal model that facilitated the best trade-off between model complexity and prediction accuracy. ConclusionsA multimodal SVR can be used to predict the language outcome. SignificanceThe developed multimodal SVR models in this study can be utilized to calculate the language outcomes of different resection plans prior to surgery and select the optimal surgical plan.

Resection of Temporal Neocortex During Multiple Hippocampal Transections for Mesial Temporal Lobe Epilepsy Does not Affect Seizure or Memory Outcome.

Multiple hippocampal transection (MHT) is a surgical treatment for mesial temporal lobe epilepsy associated with improved postoperative neuropsychological outcomes compared with lobectomy. To determine whether resection of the amygdala and anterior temporal neocortex during MHT affects postoperative seizure/memory outcome. Seventeen patients with normal magnetic resonance imaging and stereo-electroencephalogram-proven drug-resistant dominant mesial temporal lobe epilepsy were treated with MHT. Nine patients underwent MHT alone (MHT-) and 8 patients underwent MHT plus removal of the amygdala and anterior 4.5 cm of temporal neocortex lateral to the fusiform gyrus (MHT+). Verbal and visual-spatial memory were assessed in all patients preoperatively and in 14 patients postoperatively using the Wechsler Memory Scale. Postoperative seizure control was assessed at 12 months for all patients. Overall, 11 of 17 patients (64.7%) were Engel class 1 at 1 year (6/9 MHT-, 5/8 MHT+, P = .38), and 10 of 14 patients (71.4%) had no significant postoperative decline in either verbal or visual memory (6/8 MHT-, 4/6 MHT+, P = .42). Verbal memory declined in 2 of 8 MHT- and 1 of 6 MHT+ patients, and visual memory declined in 1 of 8 MHT- and 2 of 6 MHT+ patients. Two patients had improved visual memory postoperatively, both in the MHT+ group. MHT on the dominant side is associated with high rates of seizure freedom and favorable memory preservation outcomes regardless of the extent of neocortical resection. Preservation of the temporal neocortex and amygdala during MHT does not appear to decrease the risk of postoperative memory decline, nor does it alter seizure outcome.

Stereotactic EEG-guided laser interstitial thermal therapy for mesial temporal lobe epilepsy

ObjectiveTo determine the outcomes of combined stereo-electroencephalography-guided and MRI-guided stereotactic laser interstitial thermal therapy (LITT) in the treatment of patients with drug-resistant mesial temporal lobe epilepsy (mTLE).MethodsWe prospectively assessed the...

Red flags in epilepsy surgery: Identifying the patients who pay a high cognitive price for an unsuccessful surgical outcome

Preoperative estimates of cognitive and seizure outcome must be as accurate as possible if the candidate is to make an informed decision about epilepsy surgery. Significant declines in memory function are reported in approximately 30% of temporal lobe surgery patients. The percentage varies according to the ways in which a postoperative deterioration is defined but since the majority of outcome studies do not take into account the patient's capacity to deteriorate if they are functioning at or close to the floor of a memory test prior to surgery, the published percentages may be an underrepresentation of the true extent of memory decline following epilepsy surgery. We examined the cognitive ‘cost’ of epilepsy surgery in a consecutive series of 474 patients who underwent elective surgery for medically intractable epilepsy. All patients underwent a presurgical assessment prior to and 1year after the surgery. Reliable change indices were used to identify significant postoperative memory decline. Postoperative outcome was dichotomized using the ILAE 2008 classification. All patients in class one were classified as seizure-free (67.5% of the sample). Excluding patients already functioning at or below the 2nd percentile on standardized memory tests, 37.8% experienced a significant postoperative decline in memory function. Twelve percent experienced the ‘double hit’ of significant postoperative memory decline and ongoing seizures following surgery. Patients with pathologies other than hippocampal sclerosis and with signs of limited cognitive reserve, both in terms of memory function and overall intellectual ability were most likely to suffer a double hit. Our results indicate that caution should be exercised when operating on these patients and preoperative counseling should be tailored to reflect the likely risk/benefit ratio of a temporal lobe resection for medically intractable epilepsy in this group.

Early improvement in obstructive sleep apnea and increase in orexin levels after bariatric surgery in adolescents and young adults

BackgroundObstructive sleep apnea (OSA) associated with obesity is known to improve after bariatric surgery, but little is known about early changes in this condition after surgery. ObjectivesTo study the clinical course of OSA after bariatric surgery SettingChildren’s hospital in the United States MethodsAdolescents and young adults with obstructive sleep apnea undergoing vertical sleeve gastrectomy (n = 6) or gastric bypass (n = 1) were enrolled in this prospective study. Participants underwent formal polysomnography before and at 3 and 5 weeks after bariatric surgery. Anthropometric measurements and assay for orexin and leptin were also performed at study visits. Thirty-one adolescents who underwent 2 polysomnography studies that were 4 weeks apart served as control patients. ResultsBaseline mean (range) age of participants was 17.8 (15.4–20.7) years, 71% were male, with body mass index of 55.2 (41.3–61.6) kg/m2 and had a median apnea hypopnea index (AHI) of 15.8 (7.1–23.8) events/hour. Differences in least-square means from longitudinal analysis did not show significant differences in AHI in the control group but showed significant postoperative decline in AHI relative to baseline. AHI declined postoperatively from baseline by 9.2 events/hour (95% confidence interval: 3.8 to 14.5) at 3 weeks (P = .002) and 9.1 events/hour (95% confidence interval: 3.8 to 14.5) at 5 weeks (P = .002); there was no significant change from 3 to 5 weeks in AHI. Leptin decreased and orexin levels increased significantly by 3 weeks postoperatively. ConclusionsThese observations suggest that OSA responds early and out of proportion to weight loss after metabolic and or bariatric surgery, thus weight independent factors may at least in part be responsible for early improvement in OSA postoperatively.

Long-term memory performance after surgical treatment of unilateral temporal lobe epilepsy (TLE)

Long-term cognitive and memory performance after surgical treatment of unilateral temporal lobe epilepsy (TLE) was investigated in a series of 98 patients. Neuropsychological evaluation was performed preoperatively and after one and three years postoperatively. Fifty-eight patients (59%) became seizure-free (Engel's class I). Verbal learning and memory declined in long-term follow-up in both left and right TLE groups. Visual memory remained stable. Ongoing postoperative seizures were related to decline in the immediate recall of logical prose, and postoperative seizure-freedom to improvement in verbal fluency in patients with left TLE. There was significant variability in the individual postoperative long-term memory performance. Left side of surgery, better baseline performance and older age at surgery were identified as risk factors for individual decline in delayed verbal memory. Selected patients undergoing surgery for drug-resistant TLE are at risk for significant postoperative memory decline especially after left temporal lobe surgery. Preoperative counseling and long-term follow-up of cognitive performance in individual patients is recommended. Additionally, more accurate predictors of individual postoperative memory performance would be needed.

Low vacuum re-infusion drains after total knee arthroplasty: is there a real benefit?

Low vacuum re-infusion drains after total knee arthroplasty: is there a real benefit?