Localization of Vestibular Cortex Using Electrical Cortical Stimulation: A Systematic Literature Review.

The vestibular system plays a fundamental role in body orientation, posture control, and spatial and body motion perception, as well as in gaze and eye movements. We aimed to review the current knowledge regarding the location of the cortical and subcortical areas, implicated in the processing of vestibular stimuli. The search was performed in PubMed and Scopus. We focused on studies reporting on vestibular manifestations after electrical cortical stimulation. A total of 16 studies were finally included. Two main types of vestibular responses were elicited, including vertigo and perception of body movement. The latter could be either rotatory or translational. Electrical stimulation of the temporal structures elicited mainly vertigo, while stimulation of the parietal lobe was associated with perceptions of body movement. Stimulation of the occipital lobe produced vertigo with visual manifestations. There was evidence that the vestibular responses became more robust with increasing current intensity. Low-frequency stimulation proved to be more effective than high-frequency in eliciting vestibular responses. Numerous non-vestibular responses were recorded after stimulation of the vestibular cortex, including somatosensory, viscero-sensory, and emotional manifestations. Newer imaging modalities such as functional MRI (fMRI), Positron Emission Tomography (PET), SPECT, and near infra-red spectroscopy (NIRS) can provide useful information regarding localization of the vestibular cortex.

Posterior Fossa Intra-Axial Lesion: There Are Pathologies Beyond Metastases.

Cerebellar metastases represent the most common lesion requiring surgical treatment in the daily neurosurgical praxis. We report a rare case with Lhermitte-Duclos disease presenting to the neurosurgical outpatient department and describe our diagnostic and treatment challenges. A 57-year-old man presented with transient cerebellar manifestations, including walking difficulties, dizziness, and a persistent occipital headache. The magnetic resonance imaging demonstrated a high-intensity lesion in the right cerebellar hemisphere on T2-weighted images. We initially considered surgery to establish a histopathological diagnosis. However, the magnetic resonance spectroscopy was compatible with a dysplastic gangliocytoma of the cerebellum. Therefore, we preferred a more conservative approach. Posterior fossa contrast-enhancing lesions are much more than metastases. The role of advanced magnetic resonance in avoiding unnecessary surgical interventions is priceless.

The Role of Extra-Operative Cortical Stimulation and Mapping in the Surgical Management of Intracranial Gliomas.

BACKGROUND: Aggressive resection without compromising the patient's neurological status remains a significant challenge in treating intracranial gliomas. Our current study aims to evaluate the efficacy and safety of extra-operative stimulation and mapping via implanted subdural electrodes with or without depth (EOCSM), offering an alternative approach when awake mapping is contraindicated. METHODS: Fifty-one patients undergoing EOCSM for glioma resection in our institution formed the sample study of our current retrospective study. We assessed the effectiveness and safety of our approach by measuring the extent of resection and recording the periprocedural complications, respectively. RESULTS: The mean age of our participants was 58 years (±9.4 years). The lesion was usually located on the left side (80.4%) and affected the frontal lobe (51.0%). EOCSM was successful in 94.1% of patients. The stimulation and electrode implantation procedures lasted for a median of 2.0 h and 75 h, respectively. Stimulation-induced seizures and CSF leakage occurred in 13.7% and 5.9% of our cases. The mean extent of resection was 91.6%, whereas transient dysphasia occurred in 21.6% and transient hemiparesis in 5.9% of our patients, respectively. CONCLUSIONS: Extraoperative stimulation and mapping constitute a valid alternative mapping option in glioma patients who cannot undergo an awake craniotomy.

Bing–Neel syndrome presenting with bilateral lumbar radiculopathy: A case report of a rare clinical entity / Síndrome de Bing-Neel que se presenta con radiculopatía lumbar bilateral: reporte de caso de una entidad clínica rara

The differential diagnosis of bilateral lower extremity weakness is broad. We present a very rare case of a 48-year old male patient, with walking difficulties due to Bing–Neel syndrome. On clinical examination, there was a significant loss of muscle power in all his lower extremities key-muscle groups. The lumbar spine magnetic resonance imaging (MRI) showed only mild degenerative changes, whereas the MRI of the head indicated a diffuse meningeal thickening at the right temporal region, characterized by significant enhancement after contrast administration. Serum protein electrophoresis detected an IgM-kappa monoclonal protein. The patient received intrathecal chemotherapy with methotrexate and cytarabine, and was started on oral ibrutinib 420mg daily. In conclusion, a past medical history of Waldenstrom macroglobulinemia in conjunction with neurological manifestations should alert the treating physician for Bing–Neel syndrome. A complete diagnostic imaging and serologic protocol helps in setting the final diagnosis. Steroids are part of the treatment, but should be given after the diagnosis is set. Neurosurgical intervention is indicated for histologic confirmation in the case of diagnostic uncertainty (AU)

El diagnóstico diferencial de la debilidad bilateral de las extremidades inferiores es amplio. Presentamos un caso muy raro de un paciente masculino de 48 años, con dificultad para caminar debido al síndrome de Bing-Neel. El examen clínico reveló una pérdida significativa de fuerza muscular en todos los grupos de músculos clave de sus extremidades inferiores. La resonancia magnética de la columna lumbar reveló solamente cambios degenerativos leves. Sin embargo, la resonancia magnética de cerebro detectó engrosamiento meníngeo difuso en la región temporal derecha caracterizado por realce significativo tras la administración del contraste. La electroforesis de proteínas en suero detectó una proteína monoclonal IgM-Kappa. Inicialmente, el paciente recibió dexametasona y su situación neurológica mejoró excepcionalmente. Además, se le administró quimioterapia intratecal con metotrexato y citarabina y empezó a tomar ibrutinib oral 420mg a diario. En conclusión, un historial médico anterior de macroglobulinemia de Waldenström junto con manifestaciones neurológicas debe alertar al médico tratante sobre síndrome de Bing-Neel. Un protocolo completo de diagnóstico por imágenes y serológico ayuda a establecer el diagnóstico final. Los esteroides son parte del tratamiento, pero deben administrarse después de establecer el diagnóstico. La intervención neuroquirúrgica está indicada para confirmación histológica en caso de incertidumbre diagnóstica (AU)

Bing-Neel syndrome presenting with bilateral lumbar radiculopathy: A case report of a rare clinical entity.

The differential diagnosis of bilateral lower extremity weakness is broad. We present a very rare case of a 48-year old male patient, with walking difficulties due to Bing-Neel syndrome. On clinical examination, there was a significant loss of muscle power in all his lower extremities key-muscle groups. The lumbar spine magnetic resonance imaging (MRI) showed only mild degenerative changes, whereas the MRI of the head indicated a diffuse meningeal thickening at the right temporal region, characterized by significant enhancement after contrast administration. Serum protein electrophoresis detected an IgM-kappa monoclonal protein. The patient received intrathecal chemotherapy with methotrexate and cytarabine, and was started on oral ibrutinib 420mg daily. In conclusion, a past medical history of Waldenstrom macroglobulinemia in conjunction with neurological manifestations should alert the treating physician for Bing-Neel syndrome. A complete diagnostic imaging and serologic protocol helps in setting the final diagnosis. Steroids are part of the treatment, but should be given after the diagnosis is set. Neurosurgical intervention is indicated for histologic confirmation in the case of diagnostic uncertainty.

Association between white matter lesions and Parkinson's disease: an impact on Postural/Gait difficulty phenotype and cognitive performance.

BACKGROUND: White matter hyperintensities (WMHs) may be observed on Magnetic Resonance Imaging (MRI) in patients with Parkinson disease with or without vascular risk factors. Whether WMHs may influence motor and non-motor aspects of Parkinson disease is a subject of debate. The aim of this study is to evaluate the impact of WMH severity on various aspects of Parkinson disease in combination to the estimation of the impact of cerebrovascular risk factors. MATERIALS AND METHODS: We included a cohort of patients with Parkinson's disease who underwent MRI examination. The Fazekas visual rating scale was used to assess the severity and location of WMHs, and patient clinical characteristics were correlated with MRI data. RESULTS: All vascular risk factors were associated with higher Fazekas score in both periventricular and deep white matter. Periventricular white matter hyperintensities (PWMHs) and deep white matter hyperintensities (DWMHs) were associated with lower scores in the ACE-R cognitive assessment scale (p < 0.001). Furthermore, PWMHs and DWMHs severity was associated with higher UPDRS motor score (p < 0.001), while the Postural Instability Gait Difficulty (PIGD) phenotype was correlated with higher burden of WMHs. CONCLUSIONS: Comorbid WMHs may contribute to multi-dimension dysfunction in patients with Parkinson disease and consequently the management of vascular risk factors may be crucial to maintain motor and non-motor functions in PD.

Machine Learning in Meningioma MRI: Past to Present. A Narrative Review.

Meningioma is one of the most frequent primary central nervous system tumors. While magnetic resonance imaging (MRI), is the standard radiologic technique for provisional diagnosis and surveillance of meningioma, it nevertheless lacks the prima facie capacity in determining meningioma biological aggressiveness, growth, and recurrence potential. An increasing body of evidence highlights the potential of machine learning and radiomics in improving the consistency and productivity and in providing novel diagnostic, treatment, and prognostic modalities in neuroncology imaging. The aim of the present article is to review the evolution and progress of approaches utilizing machine learning in meningioma MRI-based sementation, diagnosis, grading, and prognosis. We provide a historical perspective on original research on meningioma spanning over two decades and highlight recent studies indicating the feasibility of pertinent approaches, including deep learning in addressing several clinically challenging aspects. We indicate the limitations of previous research designs and resources and propose future directions by highlighting areas of research that remain largely unexplored. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY STAGE: 2.

Intermediate surgical outcome in patients suffering poor-grade aneurysmal subarachnoid hemorrhage. A single center experience.

BACKGROUND: It is known that patients suffering poor-grade aneurysmal subarachnoid hemorrhage (aSAH) have a dismal prognosis. The importance of early intervention is well established in the pertinent literature. Our aim was to assess the functional outcome and overall survival of these patients undergoing surgical clipping. MATERIAL AND METHODS: In the current retrospective study we included all consecutive poor-grade patients after spontaneous SAH who presented at our institution over an eight-year period. All participants suffering SAH underwent brain CT angiography (CTA) to identify the source of hemorrhage. We assessed the severity of hemorrhage according to the Fisher grade classification scale. All patients were surgically treated. The functional outcome was evaluated six months after the onset with the Glasgow Outcome Scale. Finally, we performed logistic and Cox regression analyses to identify potential prognostic risk factors. RESULTS: Our study included twenty-three patients with a mean age of 53 years. Five (22%) patients presented with Hunt and Hess grade IV, and eighteen (78%) with grade V. The mean follow-up was 15.8 months, while the overall mortality rate was 48%. The six-month functional outcome was favorable in 6 (26%) patients. The vast majority of our patients died between the 15th and the 60th post-ictal days. We did not identify any statistically significant prognostic factors related to the patient's outcome and/or survival. CONCLUSIONS: Poor-grade aSAH patients may have a favorable outcome with proper surgical management. Large-scale studies are necessary for accurately outlining the prognosis of this entity, and identifying parameters that could be predictive of outcome.

The Use of Standardized Intraoperative Language Tests in Awake Craniotomies: A Scoping Review.

Assessment of speech and language functions is an essential part of awake craniotomies. Although standardized and validated tests have several advantages compared to homemade (or mixed) batteries, in the literature it is unclear how such tests are used or whether they are used at all. In this study, we performed a scoping review in order to locate standardized and validated intraoperative language tests. Our inquiry included two databases (PubMED and MEDLINE), gray literature, and snowball referencing. We discovered 87 studies reporting use of mixed batteries, which consist of homemade tasks and tests borrowed from other settings. The tests we found to meet the validation and standardization criteria we set were ultimately three (n = 3) and each one has its own advantages and disadvantages. We argue that tests with high sensitivity and specificity not only can lead to better outcomes postoperatively, but they can also help us to gain a better understanding of the neuroanatomy of language.

Clinically Silent Small Vessel Disease of the Brain in Patients with Obstructive Sleep Apnea Hypopnea Syndrome.

Obstructive sleep apnea hypopnea syndrome (OSAHS) is associated with increased risk of cerebrovascular disease. The aim of the present study was to investigate the association between the presence of the small vessel disease (SVD) of the brain in patients with OSAHS. The study included 24 patients with moderate to severe OSAHS and 34 healthy volunteers. All the subjects underwent magnetic resonance imaging (MRI) of the brain, in order to sought periventricular white matter (PVWM), deep white matter (DWM) and brainstem SVD. Among patients with OSAHS, 79.1% had SVD (grade 1-3, Fazekas score) in DWM and 91.7% in PVWM while 22.4% had brainstem-white matter hyperintensities (B-WMH). Patients with OSAHS had a much higher degree of SVD in the DWM and PVWM compared to the control group (p < 0.001). The multivariate analysis showed an independent significant association of OSAHS with SVD (DWM and PVWM) (p = 0.033, OR 95% CI: 8.66 (1.19-63.08) and: p = 0.002, OR 95% CI: 104.98 (5.15-2141)). The same analysis showed a moderate association of OSAHS with B-WMH (p = 0.050, OR 15.07 (0.97-234.65)). Our study demonstrated an independent significant association of OSAHS with SVD and a moderate association of OSAHS with B-WMH.

A meta-analysis on potential modifiers of LITT efficacy for mesial temporal lobe epilepsy: Seizure-freedom seems to fade with time.

BACKGROUND: The efficacy of laser interstitial thermal therapy (LITT) in mesial temporal lobe epilepsy (MTLE) has not been clearly established yet. OBJECTIVE: We conducted a meta-analysis to estimate the efficacy of LITT for TLE (Q1). We also examined the effect of the patient's age (Q2), the total ablation volume (TAV) (Q3), the strength of the MRI unit (Q4), the type of the utilized stereotactic platform (Q5), and the follow up period (Q6) on the patient's outcome. METHODS: Fixed- and random-effects model meta-analysis was conducted to assess the proportion estimate for each parameter individually. Kaplan-Meier survival-analysis was performed on the available individual patient time-to-first seizure data. RESULTS: Sixteen studies with 575 patients fulfilled our eligibility criteria. The efficacy of LITT was 0.547 (95%CI: 0.506-0.588). Our statistical analysis had robust results after stratification according to the study population (Q2; p = 0.3418), and the type of the utilized stereotactic platform (Q5; p = 0.286), whereas the role of the TAV (Q3; p = 0.058) and strength of the magnetic field (Q4; p = 0.062) in seizure control remained unclear. The median seizure-free period (Q6) was 0.643 (0.569-0.726) and 0.467 (0.385-0.566) for the one- and the two-year follow up. CONCLUSIONS: LITT seems to offer a viable alternative to resective surgery, with a moderate efficacy and enduring results. Higher ablation volumes may be associated with improved seizure control, although our current study provided no statistically significant data. More high-quality studies are required to highlight the role of LITT in epilepsy surgery, particularly in the pediatric population.

Bing-Neel syndrome presenting with bilateral lumbar radiculopathy: A case report of a rare clinical entity.

The differential diagnosis of bilateral lower extremity weakness is broad. We present a very rare case of a 48-year old male patient, with walking difficulties due to Bing-Neel syndrome. On clinical examination, there was a significant loss of muscle power in all his lower extremities key-muscle groups. The lumbar spine magnetic resonance imaging (MRI) showed only mild degenerative changes, whereas the MRI of the head indicated a diffuse meningeal thickening at the right temporal region, characterized by significant enhancement after contrast administration. Serum protein electrophoresis detected an IgM-kappa monoclonal protein. The patient received intrathecal chemotherapy with methotrexate and cytarabine, and was started on oral ibrutinib 420mg daily. In conclusion, a past medical history of Waldenstrom macroglobulinemia in conjunction with neurological manifestations should alert the treating physician for Bing-Neel syndrome. A complete diagnostic imaging and serologic protocol helps in setting the final diagnosis. Steroids are part of the treatment, but should be given after the diagnosis is set. Neurosurgical intervention is indicated for histologic confirmation in the case of diagnostic uncertainty.

Spasm of the near reflex: a common diagnostic dilemma?

AIM: To report the clinical characteristics and diagnostic procedures used in patients with spasm of the near reflex (SNR), in order to present common investigation strategies and diagnostic pitfalls. METHODS: Retrospective case series of twenty-two patients, mainly children, with SNR or accommodation spasm (AS). AS was diagnosed on the basis of blurred vision and a difference of ≥2 dioptres between manifest and cycloplegic retinoscopy. If esotropia and miosis were present, the patients were diagnosed with SNR. All patients underwent visual acuity testing, orthoptic evaluation, assessment of refraction before and after cycloplegia, and dilated fundoscopy. Additional diagnostic investigations, such as neuroimaging, lumbar puncture (LP), electrophysiology and blood tests, were also recorded. Screen use among children was assessed in hours per day. RESULTS: There were 19 female and 3 male patients (age range 7-33y, median=10y). Seventeen patients had AS and 5 patients had SNR, with episodic blurry vision and headaches being the most common symptoms. Brain neuroimaging was performed in six patients (27%), although only one had a history of brain trauma. Two of those patients underwent visual evoked potentials and three also underwent LP and received intravenous steroid therapy. The majority of patients (90%) reported prolonged daily screen time (>2h/d), and in 55% of cases there were concurrent social problems or psychological triggers. Treatment consisted of careful explanation of the condition, atropine 1% eye drops and full cycloplegic correction by means of bifocal glasses. CONCLUSION: The diagnosis of SNR and AS may be challenging, because symptoms are usually intermittent and nonspecific, and a large number of patients are often subjected to redundant and potentially time-consuming examinations and treatment, that may exaggerate the underlying psychological disorder. Hence, detailed clinical testing and assessment of psychosocial profile is necessary, in order to avoid unnecessary investigations. Neuroimaging should be performed only in selected cases. Finally, due to prolonged screen use SNR and AS may become more frequent in the future.

The Greek linguistic assessment for awake brain surgery: development process and normative data.

Language mapping with direct electrical stimulation is considered the gold standard in surgical treatment of brain tumors. Assessing a variety of language functions intraoperatively can affect the extent of the tumor resection as well as the patient's postoperative quality of life. Although most tests include preoperative sessions where tasks are personalised to each patient, normative data are essential since they can ensure that the presented stimuli can be responded appropriately. In this study, we describe the development and standardisation procedures of the first linguistic test in Greek, designed specifically for brain mapping during awake craniotomies. The tasks are developed to comply with the special conditions and restrictions of language assessment inside the operating room. Each task is controlled for various psycholinguistic and lexical variables and it is associated with specific neuroanatomical areas and linguistic processes. Our population consists of 80 right-handed, healthy, Greek-speaking individuals aged 20-60 years. We found only a few main effects and interactions of demographic variables on our test scores. Most differences were found between age groups, since older participants tend to perform slightly worse than younger ones. Therefore, percentiles and cut-off scores were calculated separately for each demographic group. Regarding the clinical application of GLAABS, we describe the procedures we followed to administer it to brain tumor patients from our department and also discuss how sensitivity and specificity can affect patients' postoperative course.

The Role of the T2-FLAIR Mismatch Sign as an Imaging Marker of IDH Status in a Mixed Population of Low- and High-Grade Gliomas.

Our study evaluated the role of the T2-fluid-attenuated inversion recovery (FLAIR) mismatch sign in detecting isocitrate dehydrogenase (IDH) mutations based on a mixed sample of 24 patients with low- and high- grade gliomas. The association between the two was realized using univariate and multivariate logistic regression analysis. There was a substantial agreement between the two raters for the detection of the T2-FLAIR mismatch sign (Cohen's kappa coefficient was 0.647). The T2-FLAIR mismatch sign when co-registered with the degree of tumor homogeneity were significant predictors of the IDH status (OR 29.642; 95% CI 1.73-509.15, p = 0.019). The probability of being IDH mutant in the presence of T2-FLAIR mismatch sign was as high as 92.9% (95% CI 63-99%). The sensitivity and specificity of T2-FLAIR mismatch sign in the detection of the IDH mutation was 88.9% and 86.7%, respectively. The T2-FLAIR mismatch sign may be an easy to use and helpful tool in recognizing IDH mutant patients, particularly if formal IDH testing is not available. We suggest that the adoption of a protocol based on imaging and histological data for optimal glioma characterization could be very helpful.

Machine learning assisted DSC-MRI radiomics as a tool for glioma classification by grade and mutation status.

BACKGROUND: Combining MRI techniques with machine learning methodology is rapidly gaining attention as a promising method for staging of brain gliomas. This study assesses the diagnostic value of such a framework applied to dynamic susceptibility contrast (DSC)-MRI in classifying treatment-naïve gliomas from a multi-center patients into WHO grades II-IV and across their isocitrate dehydrogenase (IDH) mutation status. METHODS: Three hundred thirty-three patients from 6 tertiary centres, diagnosed histologically and molecularly with primary gliomas (IDH-mutant = 151 or IDH-wildtype = 182) were retrospectively identified. Raw DSC-MRI data was post-processed for normalised leakage-corrected relative cerebral blood volume (rCBV) maps. Shape, intensity distribution (histogram) and rotational invariant Haralick texture features over the tumour mask were extracted. Differences in extracted features across glioma grades and mutation status were tested using the Wilcoxon two-sample test. A random-forest algorithm was employed (2-fold cross-validation, 250 repeats) to predict grades or mutation status using the extracted features. RESULTS: Shape, distribution and texture features showed significant differences across mutation status. WHO grade II-III differentiation was mostly driven by shape features while texture and intensity feature were more relevant for the III-IV separation. Increased number of features became significant when differentiating grades further apart from one another. Gliomas were correctly stratified by mutation status in 71% and by grade in 53% of the cases (87% of the gliomas grades predicted with distance less than 1). CONCLUSIONS: Despite large heterogeneity in the multi-center dataset, machine learning assisted DSC-MRI radiomics hold potential to address the inherent variability and presents a promising approach for non-invasive glioma molecular subtyping and grading.

Dissecting the default mode network: direct structural evidence on the morphology and axonal connectivity of the fifth component of the cingulum bundle.

OBJECTIVE: Although a growing body of data support the functional connectivity between the precuneus and the medial temporal lobe during states of resting consciousness as well as during a diverse array of higher-order functions, direct structural evidence on this subcortical circuitry is scarce. Here, the authors investigate the very existence, anatomical consistency, morphology, and spatial relationships of the cingulum bundle V (CB-V), a fiber tract that has been reported to reside close to the inferior arm of the cingulum (CingI). METHODS: Fifteen normal, formalin-fixed cerebral hemispheres from adults were treated with Klingler's method and subsequently investigated through the fiber microdissection technique in a medial to lateral direction. RESULTS: A distinct group of fibers is invariably identified in the subcortical territory of the posteromedial cortex, connecting the precuneus and the medial temporal lobe. This tract follows the trajectory of the parietooccipital sulcus in a close spatial relationship with the CingI and the sledge runner fasciculus. It extends inferiorly to the parahippocampal place area and retrosplenial complex area, followed by a lateral curve to terminate toward the fusiform face area (Brodmann area [BA] 37) and lateral piriform area (BA35). Taking into account the aforementioned subcortical architecture, the CB-V allegedly participates as a major subcortical stream within the default mode network, possibly subserving the transfer of multimodal cues relevant to visuospatial, facial, and mnemonic information to the precuneal hub. Although robust clinical evidence on the functional role of this stream is lacking, the modern neurosurgeon should be aware of this tract when manipulating cerebral areas en route to lesions residing in or around the ventricular trigone. CONCLUSIONS: Through the fiber microdissection technique, the authors were able to provide original, direct structural evidence on the existence, morphology, axonal connectivity, and correlative anatomy of what proved to be a discrete white matter pathway, previously described as the CB-V, connecting the precuneus and medial temporal lobe.

Brain volume dynamics in multiple sclerosis. A case-control study.

Objectives: In this study, we aimed to explore the extent and clinical relevance of brain volume dynamics in relapsing remitting multiple sclerosis (RRMS). Methods: Sixty-three patients with RRMS with a disease duration of about 5 years (36 women, mean age 39.9 ± 9.4 years; mean EDSS1.4 ± 1.2, mean relapse rate 0.98 ± 1.17) and 50 healthy control individuals (24 women, mean age 39.1 ± 10.2 years) were recruited and imaged on a MRI scanner by using post-gadolinium high-resolution3D T1W sequences. Cross-sectional and longitudinal volumetric data were obtained by using SIENA(X) and FIRST software. Results: Patients showed significantly lower subcortical volumes compared to healthy controls. Interestingly, the educational level predicted the rate of right thalamus atrophy. The mean annualized percentage of brain volume change (aPBVC) was -0.92% (±1.64%) and was presented in higher rates during the first five years after MS diagnosis. Conclusion: Brain atrophy mainly involved subcortical grey matter structures and was more conspicuous during the first years of MS diagnosis. The buffering role of education in atrophy was also corroborated by this study.

Complications after Anterior Temporal Lobectomy for Medically Intractable Epilepsy: A Systematic Review and Meta-Analysis.

BACKGROUND: The efficacy of surgery in the management of patients with longstanding temporal lobe epilepsy has been established. Anterior temporal lobectomy (ATL) is the most frequently implemented procedure. However, there is an obvious need to assess its perioperative safety. OBJECTIVE: We conducted a meta-analysis to estimate the postoperative mortality (Q1) and morbidity (Q2) associated with ATL for medically intractable epilepsy. In addition, we tried to identify the most frequent complications after ATL and assess their relative frequency (Q3) in children and adults. METHODS: Fixed- and random-effects model meta-analysis was conducted to assess the proportion estimate for each outcome individually. RESULTS: The postoperative mortality and cumulative morbidity were estimated to be as high as 0.01 (95% CI: 0.01, 0.02) and 0.17 (95% CI: 0.12, 0.24), respectively. Psychiatric disorders were the most common postoperative complications after ATL, with an estimated frequency as high as 0.07 (95% CI: 0.04, 0.10), followed by visual field defects (0.06; 0.03, 0.11), and cognitive disorders (0.05; 0.02, 0.10). Less frequent complications included hemiparesis and language disorders (0.03; 0.01, 0.06), infections (0.03; 0.02, 0.04), hemorrhage (0.02; 0.01, 0.05), cranial nerve deficits (0.03; 0.02, 0.05), extra-axial fluid collections (0.02; 0.01, 0.03), and medical complications (0.02; 0.01, 0.03). CONCLUSIONS: Even though the mortality after ATL is minimal, the overall morbidity cannot be ignored. Psychiatric disturbances, visual field defects, and cognitive disorders are the most common postoperative complications, and should be considered during the preoperative planning and consultation.