Postoperative Neurological Outcome Research Articles

Diagnostic accuracy of intraoperative neuromonitoring in transcarotid artery revascularization

BackgroundIn recent years, transcarotid artery revascularization (TCAR) has emerged as a safe and effective alternative to carotid artery stenting. While intraoperative neuromonitoring (IONM) techniques such as electroencephalogram (EEG) and somatosensory...

Neurophysiological identification and differentiation between the motor and sensory roots in pediatric spinal cord lipoma surgery

BackgroundRadical resection of spinal cord lipomas reduces the rate of re-tethering. Current conventional neurophysiological mapping techniques are not able to differentiate between crucial motor nerve roots and sensory roots. Enhanced differentiation could contribute to complete resection. We present our experience with a double-train paradigm to differentiate between motor and sensory roots.MethodsIn children undergoing spinal cord lipoma resection, the double-train mapping paradigm was used with an inter-train interval of 60 ms. Given the longer recovery time due to the H-reflex, a single muscle response was presumed to be elicited from a sensory root, and a double muscle response from a motor root. The primary endpoint was postoperative neurological outcome and bladder function at discharge.ResultsWe included 8 children undergoing 10 lipoma resections between 2016 and 2023. Double-train mapping was used in all cases. Motor and sensory roots were clearly differentiated in 6 cases and altered the course of surgery in 4 cases.Post-surgery, no sensory and motor function worsened within 3 months. Bladder function was stable in six and improved in two children. In two patients, bladder function worsened slightly at 3 months and 6 months, at which point one patient was re-operated on for re-tethering.ConclusionIntraoperative mapping with the double-train paradigm reliably differentiated between motor and sensory nerve roots. Informing the surgeon on the specific function of a tethering root may help to maximize resection without risking major neurological deficits.

Evaluation of needle to nerve interaction for neurological complications in ultrasound-guided interscalene brachial plexus blocks

BackgroundThe use of regional anesthesia techniques carries a well-known risk of perioperative neurological complications. The interscalene approach to brachial plexus block (ISB) is associated with the largest risk of neurological complications of any peripheral nerve block. The reported incidence of nerve injury after ISB varies, with estimates ranging from 0.5 % to 3 % of cases. In this prospective study, we sought to correlate the needle-to-nerve interaction during ISB procedures with the development of post-operative neurological outcomes. MethodsA novel grading system was developed to categorize various needle tip positions during ISB procedures. De-identified ultrasound recordings were graded post-procedure by two independent radiologists. These video grades were correlated with the incidence of post-procedural numbness or paresthesia and post-operative pain scores in the PACU and 24 hours postoperatively. Results108 patient videos were included for analysis. Zero videos received grade 1 (intraneural injection), 20 % received grade 2 (injection with needle against nerve root), 68 % received grade 3 (injection inside brachial plexus sheath), and 12 % received grade 4 (injection external to sheath). There was no statistical difference in terms of post-operative neurological complications or pain scores across the grades. Only four patients experienced post-operative neurologic complications on day one, and seven patients had neurological symptoms on day two. All symptoms resolved by post-operative day five. ConclusionsOur scoring system did not reveal relationship between more aggressive needling techniques and adverse post-procedural neurological symptoms. There was also no difference in pain scores across video grades, indicating that injection within the nerve sheath did not lead to better postoperative pain scores compared to injection outside the sheath. Since no procedures were found to be intraneural by the reviewing radiologists, no relationship between intraneural needling and adverse neurological outcomes could be elucidated. Larger studies in diverse settings may be required to capture greater variation in the block grades for more statistical power.

The Improvement of Intraoperative Motor Evoked Potential after Decompression in Cervical Compressive Myelopathy: Its Significance and Related Factors

Objective: This study investigated the relationship between intraoperative motor evoked potential (MEP) improvement after decompression surgery for cervical compressive myelopathy (CCM) and postoperative neurological outcomes, and preoperative factors influencing MEP improvement.Methods: MEP amplitudes were measured prospectively before and after decompression in 38 patients with CCM. The patients were categorized into three groups according to whether the intraoperative MEP slightly decreased, slightly increased, or significantly increased. Functional outcomes were assessed using the recovery rate (RR) and absolute improvement (AI) of the modified Japanese Orthopaedic Association score on postoperative days (PODs) 7 and 28. The preoperative characteristics and intraoperative MEP changes among the three groups were compared. Additionally, the correlation between the increase in MEP amplitude during surgery and the extent of improvement in functional outcomes was investigated.Results: The significantly increased MEP group had a lower baseline MEP amplitude (152.46 µV; p=0.009). In the slightly decreased MEP group, the RR was 27.98 ± 32.29% at POD 7 (p=0.010) and 11.61 ± 69.84% at POD 28 (p=0.200); the AI was 0.79 ± 0.80 at POD 7 (p=0.010) and 0.79 ± 1.42 at POD 28 (p=0.100). In the slightly increased MEP group, the RR was 23.75 ± 28.36% at POD 7 (p=0.040) and 28.47 ± 43.38% at POD 28 (p=0.070); the AI was 1.00 ± 1.21 at POD 7 (p=0.030) and 1.08±1.88 at POD 28 (p=0.100). In the significantly increased MEP group, the RR was 41.06 ± 32.01% at POD 7 (p=0.009) and 59.78 ± 34.52% at POD 28 (p=0.006); the AI was 3.08 ± 2.07 at POD 7 (p=0.009) and 4.33 ± 2.54 at POD 28 (p=0.006). Greater intraoperative MEP improvement correlated with better postoperative recovery at 1 month (RR, p=0.010; AI, p<0.001).Conclusion: Intraoperative MEP monitoring is valuable for predicting postoperative neurological outcomes in CCM patients, particularly those with lower baseline MEP amplitudes. Significant intraoperative MEP improvements are associated with better functional recovery. These findings underscore the importance of MEP monitoring in optimizing surgical strategies and predicting neurological recovery.

Surgical Outcomes of Patients with Benign Spinal Tumors: Insights from A Prospective Quasi Experimental Study

Background: Spinal tumor is one of the causes of back pain, sensory motor deficit and bowel bladder dysfunction. Evaluation of postoperative mortality, morbidity and outcomes after resection of spinal cord tumors is critical to the practice of evidencebased medicine. Hence, it is important to carefully examine surgical outcomes at an institutional level. Objectives: The aim of the study was to describe the results of benign spinal tumor after surgical treatment according to location. Materials & Method: This quasi-experimental study was conducted in the Department of Neurosurgery, Chittagong Medical College and Hospital for a period of 12 months. Twenty eight cases of benign spinal tumor underwent surgical treatment were enrolled in the study. Average hospital stay from surgery to discharge was 12-15 days. Postoperative neurological outcome in Frankel’s grade and bowel bladder involvement were assessed from 1st POD to 3rd month after surgery and data were recorded at 7th POD, 1st month and 3rd month after surgery. Collected data were analyzed by using SPSS-23. Results: Among the 28 cases, 15 were men and 13 were women. The mean age was 36.19 (±14.29) years and age range was 15 to 62 years. Twenty three (82.14%) patients improved by at least one Frankel grade and remaining five (17.86%) patients maintained their preoperative Frankel grade. Out of eight (28.6%) cases with absent bowel bladder dysfunction before surgery six (75%) recovered within three months. Postoperative deterioration was not observed in any of the included case. Ten (35.7%) patients had excellent outcome (having Frankel grade E with normal bowel bladder control) and 18 patients (64.3%) had good/fair outcome (partial recovery or clinically insignificant recovery) after 3 months. Age, gender and location (axial and sagittal) of benign spinal tumor were not found to have significant variation of neurological outcome. Conclusion: Majority of patients irrespective of the location (axial/sagittal) of the tumor had a favorable clinical outcome three months after the operation. Bang. J Neurosurgery 2024; 13(2): 130-139

Effect of surgical resection extent on neurological prognosis of adult intradural spinal teratomas.

Intradural spinal teratomas are very rare in adults and may cause severe neurological deficits. Tumors often tightly attached to the spinal cord, making complete resection difficult. The purpose of this study was to evaluate the impact of surgical resection extent on neurologic outcomes in these patients. A retrospective study of IST patients who underwent microsurgery in our center was performed. Age, sex, symptoms, duration of symptoms, tumors size, neurologic status, extent of resection, and surgical outcome were reviewed for each patient. The Kruskal-Wallis test and multivariate logistic regression were used to assess affecting factors on neurological outcomes. A total of 26 adult patients underwent microsurgical management were studied. The mean age at surgery was 41.3 years (range 23-66 years). The mean follow-up was 109.5 months (range 17-216 months). Gross total resection (GTR) was achieved in 12 (46.2%) cases and subtotal resection (STR) in 14 (53.8%) cases. 6 patients (23.1%) had recurrence, and the mean time to recurrence (TTR) was 86.0 months (range 3-168 months) after the first surgery. No recurrence was found after the second surgery during follow-up. All tumors were pathologically confirmed as mature teratomas. In analysis of neurological outcomes, patients with shorter symptom duration (p = 0.035) and lower MMcS grade (p = 0.025) had better postoperative neurological outcomes. The neurological prognosis of STR patients was better than that of GTR patients (p = 0.041). Multivariate logistic regression confirmed that the extent of resection differences remained significant (p = 0.017). Surgical resection is optimal therapeutical management of IST and can obtain a good prognosis. STR appeared to be superior to GTR in terms of neurological improvement. Considering the characteristics of slow growth and long TTR of IST, STR may be a feasible option for highly adherent tumors.

Intraoperative Neurophysiologic Monitoring Improves Neurologic Outcomes in Eloquent Brain Areas and Aids in Increasing the Volume of Resected Glioma: Current Results Compared With Historical Controls.

This study aims to show the impact of multimodal intraoperative neurophysiologic monitoring (IOM) in glioma surgery in preventing severe neurologic injury and increasing tumor removal by comparing the historical cases where IOM was not used. Fifty-nine patients with glial tumors located nearby the eloquent area, operated by the same surgeon, were included in the study. Between 2008 and 2012, 21 patients were operated on without IOM (non-IOM); between 2018 and 2021, 38 patients were operated on with IOM. The preoperative Karnofsky performance status scale (KPSS) scores were not statistically significant between non-IOM and IOM groups (P = 0.351). Postoperative KPSS (mean 97.9) scores were 15.7% higher than preoperative KPSS (mean 84.6) in the IOM group (P < 0.001). Conversely, there was no significant difference between preoperative and postoperative KPSS scores (mean 78.5 and 81.5, respectively) in the non-IOM group (P = 0.472). Moreover, postoperative KPSS scores were 20% higher in the IOM group than in the non-IOM group (P < 0.001). Preoperative tumor sizes were double the size in the non-IOM group compared with those in the IOM group (P = 0.007). Nevertheless, the postsurgery tumor residue volume was almost four times higher in the non-IOM group than that in the IOM group (P = 0.035). A median of 93.35% of the tumor volume was resected in the IOM group, but only 77.26% of the tumor was removed in the non-IOM group (P < 0.001). Intraoperative neurophysiologic monitoring helps in a more radical tumor resection in glial tumors located close to the eloquent area, improves postoperative neurologic outcomes, and maintains the patient's quality of life.

Correlation of older age with better progression-free survival despite less aggressive resection in nonfunctioning pituitary adenomas.

Nonfunctioning pituitary adenomas (NFPAs) present at a wide range of ages; it is possible that variable outcomes are based on patient age at presentation. This study aimed to explore long-term outcomes of patients with NFPAs following endonasal transsphenoidal surgery (ETS), considering age stratification. This retrospective study included 228 patients with NFPAs who underwent ETS, with a median follow-up period of 63 months. The outcomes included progression-free survival (PFS) rates and neurological and endocrinological outcomes. Age-stratified Kaplan-Meier and Cox proportional hazards analyses were performed. Patients were classified into four age groups: ≤ 49, 50-59, 60-69, and ≥ 70 years. Age-stratified analysis showed a significant correlation between age and PFS in NFPAs (5-year PFS rates: 63.0% in those ≤ 49 years, 76.7% in those 50-59 years, 85.0% in those 60-69 years, and 88.1% in those ≥ 70 years; p = 0.001, log-rank test). Bivariate (HR 1.03, 95% CI 1.01-1.05; p = 0.001) and multivariable (HR 1.03, 95% CI 1.02-1.05; p = 0.001) analyses demonstrated that older age was significantly associated with longer PFS. Multivariable analysis also demonstrated that smaller maximum tumor diameter (HR 0.77, 95% CI 0.60-0.99; p = 0.036) and gross-total resection (HR 8.55, 95% CI 3.90-18.75; p = 0.001) were significantly associated with longer PFS. Multivariable logistic regression analysis demonstrated that only younger age was associated with postoperative improvement of male hypogonadism (HR 0.91, 95% CI 0.84-0.99; p = 0.019). Other postoperative neurological and endocrinological outcomes were not significantly associated with age. Older patients with NFPAs treated with ETS demonstrated a longer PFS. Of endocrinological outcomes studied, only male hypogonadism improvement was associated with younger patient age.

Minimally invasive keyhole craniotomies for microsurgical clipping of cerebral aneurysms: comparative meta-analysis of the mini-pterional and supraorbital keyhole approaches.

Axel Perneczky is responsible for conceptualizing the "keyhole" philosophy as a new paradigm of minimal invasiveness within cranial neurosurgery. Keyhole neurosurgery aims to limit approach-related traumatization and minimize brain retraction while still enabling the neurosurgeon to achieve operative goals. The supraorbital keyhole craniotomy (SOKC) and minipterional (pterional keyhole, PKC) approaches have become mainstays for clipping intracranial aneurysms. While studies have compared these approaches to the traditional pterional craniotomy for clipping cerebral aneurysms, head-to-head comparisons of these workhorse keyhole approaches remain limited. The authors queried three databases per PRISMA guidelines to identify all studies comparing the SOKC to the PKC for microsurgical clipping of cerebral aneurysms. Of 148 unique studies returned on initial query, a total of 5 studies published between 2013 and 2019 met inclusion criteria. Where applicable, quantitative meta-analysis was performed via the Mantel-Haenszel method using Review Manager v5.4 (Nordic Cochrane Centre, Cochrane Collaboration, Copenhagen, Denmark). Risk of bias (ROB) was assessed using the Cochrane ROBINS-I tool, and all studies were assigned a Level of Evidence (I-V). Across all five studies, the mean age ranged from 53.0 to 57.5 years old, and the cohort consisted of more females (n = 403, 60.6%) than males. The proportion of patients presenting with ruptured aneurysmal SAH was comparable between the SOKC and PKC cohorts (p = 0.43). Clipping rate [defined as the rate of successful aneurysm clip deployment with successful intraoperative occlusion] (OR 1.52 [0.49, 4.71], I2 = 0%, p = 0.47), final occlusion rates (OR 1.27 [0.37, 4.32], p = 0.70), and operative durations (SMD 0.33 [-0.83. 1.49], I2 = 97%, p = 0.58) were comparable regardless of approach used. Furthermore, rates of intraoperative rupture (OR 1.51 [0.64, 3.55], I2 = 0, p = 0.34), postoperative hemorrhage (OR 1.49 [0.74, 3.01], I2 = 0, p = 0.26), postoperative vasospasm (OR 0.94 [0.49, 1.80], I2 = 63, p = 0.86), and postoperative infection (OR 0.70 [0.16, 2.99], I2 = 0%, p = 0.63) were equivocal across SOKC and PKC cohorts. The PKC and SOKC approaches appear to afford comparable outcomes when used for open microsurgical clipping of cerebral aneurysms in select patients with both ruptured and unruptured aneurysms. Both are associated with excellent clipping and occlusion rates, minimal perioperative complication profiles, and favorable postoperative neurologic outcomes. Further investigations are merited so clinicians can further parse out the indications and contraindications for each keyhole approach.

Neurosurgical resection of multiple brain metastases: outcomes, complications, and survival rates in a retrospective analysis

PurposeThis study investigates the outcomes of microsurgical resection of multiple brain metastasis (BMs).MethodsThis retrospective, monocentric analysis included clinical data from all consecutive BM patients, who underwent simultaneous resection of ≥ 2 BMs between January 2018 and May 2023. Postoperative neurological and functional outcomes, along with perioperative complications, as well as survival data were evaluated.ResultsA total of 47 patients, with a median age of 61 years (IQR 48–69), underwent 73 craniotomies (median 2; range 1–3) for resection of 104 BMs. Among patients, 80.8% presented with symptomatic BMs, causing focal neurological deficits in 53% of cases. Gross total resection was achieved in 87.2% of BMs. Karnofsky Performance Scale (KPS) scores improved in 42.6% of patients, remained unchanged in 46.8%, and worsened in 10.6% after surgery. Perioperative complications were observed in 29.8% of cases, with transient complications occurring in 19.2% and permanent deficits in 10.6%. The 30-days mortality rate was 2.1%. Logistic regression identified eloquent localization (p = 0.036) and infratentorial craniotomy (p = 0.018) as significant predictors of postoperative complications. Concerning overall prognosis, patients with permanent neurological deficits post-surgery (HR 11.34, p = 0.007) or progressive extracranial disease (HR: 4.649; p = 0.006) exhibited inferior survival.ConclusionMicrosurgical resection of multiple BMs leads to clinical stabilization or functional improvement in most patients. Although transient complications do not affect overall survival, the presence of persistent neurological deficits (> 3 months post-surgery) and progressive extracranial disease negatively impact overall survival. This highlights the importance of careful patient selection for resection of multiple BMs.

The Potential Neurological Impact of Intraoperative Hyponatremia Using Histidine-Tryptophan-Ketoglutarate Cardioplegia Infusion in Adult Cardiac Surgery.

Background and Objectives: The relationship between histidine-tryptophan-ketoglutarate (HTK)-induced hyponatremia and brain injury in adult cardiac surgery patients is unclear. This study analyzed postoperative neurological outcomes after intraoperative HTK cardioplegia infusion. Materials and Methods: A prospective cohort study was conducted on 60 adult patients who underwent cardiac surgery with cardiopulmonary bypass. Of these patients, 13 and 47 received HTK infusion and conventional hyperkalemic cardioplegia, respectively. The patients' baseline characteristics, intraoperative data, brain injury markers, Mini-Mental State Examination (MMSE) scores, and quantitative electroencephalography (qEEG) data were collected. Electrolyte changes during cardiopulmonary bypass, the degree of hyponatremia, and any associated brain insults were evaluated. Results: The HTK group presented with acute hyponatremia during cardiopulmonary bypass, which was intraoperatively corrected through ultrafiltration and normal saline administration. Postoperative sodium levels were higher in the HTK group than in the conventional cardioplegia group. The change in neuron-specific enolase levels after cardiopulmonary bypass was significantly higher in the HTK group (p = 0.043). The changes showed no significant differences using case-control matching. qEEG analysis revealed a significant increase in relative delta power in the HTK group on postoperative day (POD) 7 (p = 0.018); however, no significant changes were noted on POD 60. The MMSE scores were not significantly different between the two groups on POD 7 and POD 60. Conclusions: HTK-induced acute hyponatremia and rapid correction with normal saline during adult cardiac surgeries were associated with a potential short-term but not long-term neurological impact. Further studies are required to determine the necessity of correction for HTK-induced hyponatremia.

Prevalence of carotid artery stenosis and intra-cranial lesions in patients with aortic arch aneurysm and its association with intraoperative regional cerebral oxygen saturation and postoperative neurological outcomes.

Although aortic aneurysm is associated with vascular aging and atherosclerosis, carotid and intracranial vascular disease prevalence in patients with aortic arch aneurysm remains unclear. Similarly, the effect of carotid and intracranial lesions on postoperative outcomes is unknown. This study aimed to investigate the prevalence of carotid artery stenosis and intracranial lesions in patients with aortic arch aneurysm and its association with intraoperative regional cerebral oxygen saturation (rScO2) and postoperative neurological outcomes, including delirium and cerebral infarction. This retrospective observational study included 133 patients with true aortic arch aneurysm who underwent preoperative magnetic resonance imaging (MRI). We evaluated the prevalence of carotid and intracranial arterial lesions. Symptomatic cerebral infarction and delirium, defined by the confusion assessment method for the intensive care unit, were evaluated for their association with preoperative cerebrovascular lesions. Additionally, changes in regional saturation of the cerebral tissue at different surgical phases were evaluated for patients with and without cerebrovascular lesions. Fifteen (11.3%) patients experienced symptomatic cerebral infarction, and 64 (48.1%) had postoperative delirium. Preoperative MRI showed old infarction, microbleeds, significant carotid artery stenosis, and intracranial lesions in 21.1%, 14.3%, 10.5%, and 7.5% of the patients, respectively. White matter hyperintensities with Fazekas scale 2 were observed in 40.6% of the patients, while Fazekas scale 3 were observed in 18.8% of the patients. Preoperative MRI findings and postoperative neurological outcomes were not significantly different. Seventy-six patients underwent rScO2 monitoring intraoperatively. Changes in rScO2 in patients with and without carotid/cerebrovascular lesions were not significantly different. However, rScO2 was significantly lower in patients who developed cerebral infarction. Significant carotid artery stenosis and intracranial lesions were observed in 10.5% and 7.5% of the patients, respectively. Although preoperative MRI findings and changes in rScO2 or postoperative outcomes showed no significant association, patients with postoperative cerebral infarction showed significantly lower rScO2 intraoperatively.

A critical event frequent lead to reversible spinal cord injury during vertebral column resection surgery.

To report a "critical phase" (between osteotomy completion and correction beginning) that will frequently lead to the reversible intraoperative neurophysiological monitoring (IOM) change during posterior vertebral column resection (PVCR) surgery. The study sample consisted of 120 patients with severe spine deformity who underwent PVCR and deformity correction surgeries. Those patients were recruited consecutively from 2010 to 2018 January in our spine center. The detailed IOM data (the amplitude of MEP & SEP) and its corresponding surgical points were collected prospectively. Early and long-term postoperative neurologic outcomes were assessed for the following functions: motor, sensory, and pain at immediate postoperative and 1-year post-operation in this cases series. A total of 105 (105/120) patients presented varying degrees of IOM reduction in the critical phase; the mean IOM amplitude retention vs rescue rate was 27% ± 11.2 versus 58% ± 16.9, P < 0.01 (MEP) & 34% ± 8.3 versus 66% ± 12.4 P < 0.01 (SEP). Patients with postoperative spinal deficits often had a significantly longer IOM-alerting duration than the patients without (p < 0.01, Mann-Whitney U-test), and IOM-alerting duration greater than 39.5min was identified as an independent predictor of the risk of postoperative spinal deficits. The reversible IOM events probably often appear in the critical phase during PVCR surgery. The new postoperative spinal deficits are possible for patients without satisfied IOM recovery or alerting duration greater than 39.5min. Timely and suitable surgical interventions are useful for rescuing the IOM alerts.

Advanced perioperative assessment of neurological function in acute Stanford A aortic dissection

Objective Acute Stanford Type A aortic dissection (AAAD) is a critical condition in vascular surgery, and total aortic arch replacement surgery is the preferred method to save patients’ lives. In recent years, as clinical research has advanced, there has been a growing realization of the close association between poor postoperative outcomes in patients and neurological functional deficits. Neurological function monitoring is a medical technique used to evaluate and monitor the functional status of the nervous system. Methods This monitoring involves the assessment of various aspects of the nervous system, including but not limited to nerve conduction velocity, neuromuscular function, electroencephalographic activity, and sensory nerve transmission. Neurological function monitoring has broad clinical applications and can be used to diagnose and monitor many neurological disorders, helping physicians understand patients’ neurological functional status and guide treatment plans. During the postoperative recovery process, neurological function monitoring can assist physicians in assessing the potential impact of surgery on the nervous system and monitor the recovery of patients’ neurological function. Results Studies have shown that neurological function monitoring holds promise in predicting neurological functional prognosis and interventions for patients with aortic dissection. Conclusion Therefore, the primary objective of this study is to evaluate the effectiveness and reliability of various intraoperative neurological monitoring techniques, neuroimaging examinations, and biomarkers in predicting and assessing postoperative neurological outcomes in patients undergoing AAAD surgery.

Three-Stage Surgical Resection in Semisitting Position of Sphenocavernopetroclival-Foramen Magnum Meningioma: 3-Dimensional Operative Video.

Large meningiomas extending through the middle cranial fossa, posterior fossa, and foramen magnum (FM) represent a surgical challenge even for experienced skull base surgeons.1 Although decompression may be necessary for offering clinical improvement, surgical risks may involve cranial nerves and vascular injury. We present a case of a sphenocavernopetroclival-FM meningioma, with our surgical plan extending through the sphenoid region, FM, and posterior fossa to the anterior arch of C1. We designed a 2-day, 3-stage surgical strategy to achieve complete surgical resection for offering better long-term prognosis and satisfactory postoperative neurological outcome.2 The surgical plan was completed in 2 days of surgery: the first day the extradural part for achieving optimal tumor exposure and the second day the intradural part to tackle tumor resection in a 3-stage fashion. The first stage consisted in a far lateral approach to access the lower portion of the tumor extending from the FM to the spinal region; the second stage focused on the portion of the tumor extending through the inferior clivus and the petroclival region; and the third stage consisted in resecting the tumor extending from the petroclival region to the sphenoid region.3 A near-total resection was achieved, with a very small tumor remnant observed at the level of the tentorium on postoperative MRI, which was treated with radiosurgery owing to the young age of the patient. This is a 3-dimensional operative video showing the surgical steps of the tumor resection. The patient consented to the procedure and to the publication of her image.

1230 Intraventricular Meningioma Resection and Visual Outcomes

INTRODUCTION: Intraventricular meningiomas (IVMs) of the lateral ventricle are rare tumors that present surgical challenges due to their location. Visual field deficits (VFDs) are one risk associated with these tumors and their treatment. VFDs may be present preoperatively due to the tumor and mass effect (i.e. tumor-VFDs) or may develop postoperatively due to the surgical approach (surgical-VFDs). METHODS: Patients who received IVM resection at one academic institution (1996-2021) were retrospectively reviewed. Diffusor tensor imaging (DTI) reconstructions of the optic radiations around the tumor were performed from preoperative imaging. VFD course and resolution were documented. A systematic review was conducted for studies on surgical resection for IVMs that included &gt;5 patients and reported postoperative neurologic outcomes. RESULTS: In the institutional series, thirty-two adult patients underwent IVM resection, with gross total resection in 30 patients (93.8%). Pre-operatively, tumor-VFDs were present in 6 patients, resolving after surgery in 5. Five other patients (without pre-operative VFD) had new persistent surgical-VFDs postoperatively (5/32 patients, 15.6%) that persisted to most recent follow-up. Of the 5 patients in the institutional cohort with persistent surgical-VFD, 4 had trans-temporal and 1 had a trans-parietal approach, and all of these occurred prior to regular use of DTI in preoperative imaging. In the systematic review, 14 studies met inclusion criteria and 12 commented on visual outcomes postoperatively. Median rate of tumor-VFDs improving postoperatively was 50% (range 0 to 100%) and median rate of new postoperative surgical-VFDs was 11% (range 0 to 23%). CONCLUSIONS: Half of presenting tumor-VFDs from IVMs improve with surgery. However, new surgical-VFDs are a common neurologic deficit after IVM resection. Preoperative DTI may demonstrate distortion of the optic radiations around the tumor, thus revealing safe operative corridors to prevent surgical-VFDs.

Effect of oxygen delivery during cardiopulmonary bypass on postoperative neurological outcomes in patients undergoing cardiac surgery: A scoping review of the literature.

Reduced oxygen delivery (DO2) during cardiopulmonary bypass (CPB) was proposed as a risk factor for the development of postoperative neurological complications (PONCs), including cerebrovascular accidents (CVA), delirium, and postoperative cognitive dysfunction (POCD). We aimed to review the current evidence on the association between intraoperative DO2 and the incidence of PONCs. MEDLINE, Embase, the Cochrane Library, and Web of Science were electronically searched to identify comparative studies from inception until July 2023 that reported the association between intraoperative DO2 levels and the incidence of PONCs (as defined by the scales and diagnostic tools utilized by the studies' authors) in adults patients undergoing cardiac surgery using CPB. Of the 2513 papers identified, 10 studies, including 21,875 participants, were included. Of these, three studies reported on delirium, two on POCD, and five on CVA. Eight studies reported reduced intraoperative DO2 in patients who developed delirium and CVA. There was a lack of consensus on the cut-off of DO2 levels or the correlation between the period below these threshold values and the development of PONC. Limited data suggest that maintaining intraoperative DO2 above the critical threshold levels and ensuring adequate intraoperative cerebral perfusion may play a role in minimizing the incidence of neurological events in adult patients undergoing cardiac surgery on cardiopulmonary bypass.

Intercollicular Approach for Midbrain Cavernous Malformation: 2-Dimensional Operative Video.

Previously reported midbrain cavernous malformations often exhibit lateral expansion, making their excision through the nearest brain surface incision easier.1-5 Nevertheless, excising a midbrain cavernous malformation that lacks lateral extension can be particularly challenging because of limited access.5 The anterior midline approach is typically conducted through the interpeduncular fossa zone.3,5 Still, it restricts surgical maneuverability because of the presence of the posterior communicating artery, the posterior cerebral artery, and the oculomotor nerve. On the other hand, the posterior midline approach through the intercollicular region, although reported in only a single case, lacks technical details and postoperative neurological status.3,5 In this report, we elaborate on the feasibility of surgical manipulations for midline-located midbrain cavernous angiomas through the intercollicular region and discuss the resulting postoperative neurological outcomes.

Effect of temperature and duration of cardiopulmonary bypass on cerebral saturation.

Maintaining cerebral oxygenation is advocated to decrease these central nervous system morbidity and mortality after cardiopulmonary bypass (CPB). This study aimed to assess the effect of temperature and duration of CPB on cerebral saturation during open-heart surgeries and its correlation with postoperative neurological outcomes. Patients aged 18-60 years of either sex undergoing open-heart surgeries on CPB were included in the study. Near-infrared spectroscopy was used to monitor regional cerebral saturation (rSO2). Postoperative cognitive dysfunction (POCD) was assessed by mini-mental state examination (MMSE) and trail-making test (TMT-A). Postoperative neurological deficit was assessed clinically and by the western perioperative neurologic scale (WPNS). All patients were followed up for 6 months. Sixty patients were included in the study. After the institution of CPB, mean core body temperature (CBT) decreased from baseline (36.29 ± 0.21) till 40 min and mean rSO2 decreased from baseline (72.48 ± 3.81) till 60 min. No significant correlation was found between mean CBT and mean rSO2. For every 5-min increase in total CPB duration, a decrease of minimum rSO2 by 2.48 was observed (P < 0.001). Based on the MMSE score and TMT-A, minimum rSO2 values and POCD were significantly associated at postextubation and 24 h postextubation. Based on the WPNS score, minimum rSO2 and postoperative neurological deficit were significantly associated with 24 h postextubation (P = 0.040). Early rewarming on CPB is associated with relatively low rSO2. Intraoperative rSO2 desaturation showed a significant association with early cognitive decline, but its role is debatable in assessing late cognitive decline.

Diagnostic utility of different types of somatosensory evoked potential changes in pediatric idiopathic scoliosis correction surgery.

To evaluate the diagnostic accuracy of intraoperative somatosensory evoked potential (SSEP) monitoring and types of SSEP changes in predicting the risk of postoperative neurological outcomes during correction surgery for idiopathic scoliosis (IS) in the pediatric age group (≤ 21years). Database review was performed to identify literature on pediatric patients with IS who underwent correction with intraoperative neuromonitoring. The sensitivity, specificity, and diagnostic odds ratio (DOR) of transient and persistent SSEP changes and complete SSEP loss in predicting postoperative neurological deficits were calculated. Final analysis included 3778 patients. SSEP changes had a sensitivity of 72.9%, specificity of 96.8%, and DOR of 102.3, while SSEP loss had a sensitivity of 41.8%, specificity of 99.3%, and DOR of 133.2 for predicting new neurologic deficits. Transient and persistent SSEP changes had specificities of 96.8% and 99.1%, and DORs of 16.6 and 59, respectively. Intraoperative SSEP monitoring can predict perioperative neurological injury and improve surgical outcomes in pediatric scoliosis fusion surgery. Level 2. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .