Immediate Cranioplasty for Postcranioplasty Infection in Patients with Ventriculoperitoneal Shunt

World Neurosurg. (2018) 119:311-314

Patients with a ventriculoperitoneal (VP) shunt tend to develop epidural fluid accumulation after cranioplasty and also have a higher frequency of syndrome of the trephined after bone flap removal. Thus treatment of patients with postcranioplasty infection and a VP shunt is often challenging.

CASE DESCRIPTION: We treated 2 patients with postcranioplasty infection and a VP shunt. One patient had undergone decompressive craniectomy for cerebral hemorrhage, and the other patient had a large frontal dead space following resection of a brain tumor. Both patients were treated by immediate cranioplasty with obliteration of the epidural dead space by using a vascularized free latissimus dorsi muscle flap. In both of them, the postoperative course was uneventful without any complications.

CONCLUSIONS: Immediate cranioplasty and obliteration of the epidural dead space with a vascularized free latissimus dorsi muscle flap is an alternative for patients with postcranioplasty infection who are unfavorable candidates for temporary bone flap removal because of the risk of neurologic deterioration

Predictors of Poor Outcome in Patients Submitted to Minimally Invasive Transforaminal Lumbar Interbody Fusion

World Neurosurg. (2018) 119:488-493

Minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) has become an increasingly popular method for lumbar arthrodesis. While having similar long-term outcomes when compared with open TLIF, it decreases the amount of intraoperative blood loss and iatrogenic muscle damage, the intensity of postoperative pain, and the duration of hospital stay. However, uncertainty remains about which factors contribute to outcomes in these patients. The purpose of this study was to retrospectively analyze a cohort of patients submitted to MI-TLIF and to identify factors that can be associated with a worse postoperative outcome.

METHODS: Clinical records from 283 patients were assessed and, according to Odom’s criteria, postoperative clinical outcome at 12 months was classified as excellent, good, fair, and poor. Demographic variables, clinical data, and surgery-related data were analyzed, looking for associations between them and clinical outcome. A binomial logistic regression analysis was then performed to include those associations.

RESULTS: The main variables associated with worse prognosis (“poor” class according to Odom’s criteria) were a period of sick leave longer than 3 months before the surgery, age younger than 50 years, lytic spondylolisthesis, L5-S1 level, and occurrence of complications. These 5 conditions were included in a logistic regression analysis, and 3 of them were independently associated with poor outcome: operative complications, age younger than 50 years, and sick leave longer than 3 months before surgery. –

CONCLUSIONS: Younger patients, those on a sick leave for more than 3 months before surgery, or those who suffered surgical complications tended to have less satisfactory results after MI-TLIF.

Drivers of Variability in 90-Day Cost for Elective Anterior Cervical Discectomy and Fusion for Cervical Degenerative Disease

Neurosurgery 83:898–904, 2018

Value-based episode of care reimbursement models is being investigated to curb unsustainable health care costs. Any variation in the cost of index spine surgery can affect the payment bundling during the 90-d global period.

OBJECTIVE: To determine the drivers of variability in cost for patients undergoing elective anterior cervical discectomy and fusion (ACDF) for degenerative cervical spine disease.

METHODS: Four hundred forty-five patients undergoing elective ACDF for cervical spine degenerative diagnoses were included in the study. The direct 90-d cost was derived as sum of cost of surgery, cost associated with postdischarge utilization. Multiple variable linear regression models were built for total 90-d cost.

RESULTS: The mean 90-d direct cost was $17685 ± $5731. In a multiple variable linear regression model, the length of surgery, number of levels involved, length of hospital stay, preoperative history of anticoagulation medication, health-care resource utilization including number of imaging, any complications and readmission encounter were the significant contributor to the 90-d cost. The model performance as measured by R2 was 0.616.

CONCLUSION: There was considerable variation in total 90-d cost for elective ACDF surgery. Our model can explain about 62% of these variations in 90-d cost. The episode of care reimbursement models needs to take into account these variations and be inclusive of the factors that drive the variation in cost to develop a sustainable payment model. The generalized applicability should take in to account the differences in patient population, surgeons’ and institution-specific differences.

Improving the aesthetic outcome with burr hole cover placement in chronic subdural hematoma evacuation

Acta Neurochirurgica (2018) 160:2129–2135

The aesthetic outcome after burr hole trepanation for the evacuation of chronic subdural hematomas (cSDH) is often unsatisfactory, as the bony skull defects may cause visible skin depressions. The purpose of this study was to evaluate the efficacy of burr hole cover placement to improve the aesthetic outcome.

Methods We reviewed consecutive patients treated by burr hole trepanation for cSDH with or without placement of burr hole covers by a single surgeon between October 2016 and May 2018. The clinical data, including complications, were derived from the institution’s prospective patient registry. The primary endpoint was the aesthetic outcome, as perceived by patients on the aesthetic numeric analog (ANA) scale, assessed by means of a standardized telephone interview. Secondary endpoints were skin depression rates and wound pain, as well as complications.

Results From n = 33, outcome evaluation was possible in n = 28 patients (n = 24 male; mean age of 70.4 ± 16.1 years) with uni- (n = 20) or bilateral cSDH (n = 8). A total of 14 burr hole covers were placed in 11 patients and compared to 50 burr holes that were not covered. Patient satisfaction with the aesthetic outcome was significantly better for covered burr holes (mean ANA 9.3 ± 0.74 vs. 7.9 ± 1.0; p < 0.001). Skin depressions occurred over 7% (n = 1/14) of covered and over 92%(n = 46/50) of uncovered burr holes (p < 0.001). There was no difference in wound pain (p = 0.903) between covered and uncovered sites. No surgical site infection, cSDH recurrence, or material failure was encountered in patients who had received a burr hole plate.

Conclusions In this retrospective series, placement of burr hole covers was associated with improved aesthetic outcome, likely due to reduction of skin depressions. A randomized controlled trial is developed to investigate whether adding burr hole covers results in superior aesthetic outcomes, without increasing the risk for complications.

Reliable Identification of Benign Clinical Course in Aneurysmal Subarachnoid Hemorrhage

Neurosurgery 83:948–956, 2018

A reliable method to specifically identify low vasospasm risk in aneurysmal subarachnoid hemorrhage (aSAH) patients has not been previously proposed.

OBJECTIVE: To develop a clinical algorithm using admission aSAH clinical severity and subarachnoid blood distribution to identify patients at low risk of clinical vasospasm.

METHODS: Clinical severities, admission noncontrasted head computerized tomography (CT) scan, and incidences of vasospasm among 291 aSAH patients treated at our institutionwere evaluated. Admission head CTswere assessed for distributions of cisternal and ventricular blood. Patients with the following 4 criteria experienced considerably lower risk of vasospasm: (1) Hunt Hess grade 1 to 2, (2) Lack of thick subarachnoid blood filling 2 adjacent cisterns, (3) Lack of thick interhemispheric blood, and (4) Lack of biventricular intraventricular hemorrhage.

RESULTS: One hundred thirty-three patients (45.7%) developed cerebral vasospasm. Hunt Hess grade greater than 2 (odds ratio [OR] 4.52, 95% confidence interval [CI] 2.74-7.46), adjacent cistern blood (OR 4.1, 95% CI 2.51-6.7), interhemispheric thick blood (OR 5.72, 95% CI 3.41-9.59), and biventricular intraventricular hemorrhage (OR 1.92, 95% CI 1.19-3.02) were significant risk factors. Application of our algorithm yielded a sensitivity of 29%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 54.5%, which was superior compared to metrics from current institutional practice criteria. Inter-rater agreement was substantial at mean kappa = 0.75.

CONCLUSION: Application of our novel clinical algorithm produced successful identification of aSAH patients who experience zero risk of clinical vasospasm. Our algorithm is simple to apply with high reliability and is superior to currently available clinical and radiographic metrics.

The relationship between repeat resection and overall survival in patients with glioblastoma: a time-dependent analysis

J Neurosurg 129:1231–1239, 2018

Previous studies assessed the relationship between repeat resection and overall survival (OS) in patients with glioblastoma, but ignoring the timing of repeat resection may have led to biased conclusions. Statistical methods that take time into account are well established and applied consistently in other medical fields. The goal of this study was to illustrate the change in the effect of repeat resection on OS in patients with glioblastoma once timing of resection is incorporated.

METHODS The authors conducted a retrospective study of patients initially diagnosed with glioblastoma between January 2005 and December 2014 who were treated at Memorial Sloan Kettering Cancer Center. Patients underwent at least 1 craniotomy with both pre- and postoperative MRI data available. The effect of repeat resection on OS was assessed with time-dependent extended Cox regression controlling for extent of resection, initial Karnofsky Performance Scale score, sex, age, multifocal status, eloquent status, and postoperative treatment.

RESULTS Eighty-nine (55%) of 163 patients underwent repeat resection with a median time between resections of 7.7 months (range 0.5–50.8 months). Median OS was 18.8 months (95% confidence interval [CI] 16.3–20.5 months) from initial resection. When timing of repeat resection was ignored, repeat resection was associated with a lower risk of death (hazard ratio [HR] 0.62, 95% CI 0.43–0.90, p = 0.01); however, when timing was taken into account, repeat resection was associated with a higher risk of death (HR 2.19, 95% CI 1.47–3.28, p < 0.001).

CONCLUSIONS In this study, accounting for timing of repeat resection reversed its protective effect on OS, suggesting repeat resection may not benefit OS in all patients. These findings establish a foundation for future work by accounting for timing of repeat resection using time-dependent methods in the evaluation of repeat resection on OS. Additional recommendations include improved data capture that includes mutational data, development of algorithms for determining eligibility for repeat resection, more rigorous statistical analyses, and the assessment of additional benefits of repeat resection, such as reduction of symptom burden and enhanced quality of life.

 

Lateral lumbar interbody fusion in the elderly

J Neurosurg Spine 29:525–529, 2018

Elderly patients, often presenting with multiple medical comorbidities, are touted to be at an increased risk of peri- and postoperative complications following spine surgery. Various minimally invasive surgical techniques have been developed and employed to treat an array of spinal conditions while minimizing complications. Lateral lumbar interbody fusion (LLIF) is one such approach. The authors describe clinical outcomes in patients over the age of 70 years following stand-alone LLIF.

METHODS A retrospective query of a prospectively maintained database was performed for patients over the age of 70 years who underwent stand-alone LLIF. Patients with posterior segmental fixation and/or fusion were excluded. The preoperative and postoperative values for the Oswestry Disability Index (ODI) were analyzed to compare outcomes after intervention. Femoral neck t-scores were acquired from bone density scans and correlated with the incidence of graft subsidence.

RESULTS Among the study cohort of 55 patients, the median age at the time of surgery was 74 years (range 70–87 years). Seventeen patients had at least 3 medical comorbidities at surgery. Twenty-three patients underwent a 1-level, 14 a 2-level, and 18 patients a 3-level or greater stand-alone lateral fusion. The median estimated blood loss was 25 ml (range 5–280 ml). No statistically significant relationship was detected between volume of blood loss and the number of operative levels. The median length of hospital stay was 2 days (range 1–4 days). No statistically significant relationship was observed between the length of hospital stay and age at the time of surgery. There was one intraoperative death secondary to cardiac arrest, with a mortality rate of 1.8%. One patient developed a transient femoral nerve injury. Five patients with symptomatic graft subsidence subsequently underwent posterior instrumentation. A lower femoral neck t-score < -1.0 correlated with a higher incidence of graft subsidence (p = 0.006). The mean ODI score 1 year postoperatively of 31.1 was significantly (p = 0.003) less than the mean preoperative ODI score of 46.2.

CONCLUSIONS Stand-alone LLIF can be safely and effectively performed in the elderly population. Careful evaluation of preoperative bone density parameters should be employed to minimize risk of subsidence and need for additional surgery. Despite an association with increased comorbidities, age alone should not be a deterrent when considering stand-alone LLIF in the elderly population.

 

Supratotal Resection of Diffuse Frontal Lower Grade Gliomas with Awake Brain Mapping, Preserving Motor, Language, and Neurocognitive Functions

World Neurosurg. (2018) 119:30-39

Extended margin tumor resection beyond the abnormal area detected by magnetic resonance imaging, defined as supratotal resection, could improve the outcomes of patients with lower grade gliomas (LGGs). The aim of the present study was to assess the surgical outcomes of awake brain mapping to achieve supratotal resection with determination of the normal brain tissue boundaries beyond the tumor of frontal LGGs, in both dominant and nondominant hemispheres.

METHODS: We analyzed the data from 9 patients with diffuse frontal LGGs who had undergone supratotal resection with awake surgery from January 2016 to November 2017.

RESULTS: The frontal aslant tract was identified as the functional boundary in 4 of 5 left frontal tumor cases (80%). Working memory impairments during dorsolateral prefrontal cortex stimulation with digit span and/or visual N-back tasks were detected in all 4 patients (100%) with right-frontal tumor. The neurocognitive outcomes were significantly improved after surgery, as shown by the mean Wechsler adult intelligence scale III scores for verbal intelligence quotient (P [ 0.04) and verbal comprehension (P [ 0.03) and the mean Wechsler memory scale-revised scores for generalized memory (P [ 0.04) and delayed recall (P [ 0.04).

CONCLUSIONS: The results of the present study have provided evidence that awake mapping can enable the preservation of higher neurocognitive function, including working memory and spatial cognition in patients with nondominant right frontal tumors. Despite the small number of cases, our findings suggest the surgical benefit of awake surgery for supratotal resection of diffuse frontal LGGs.

The microneurosurgical anatomy legacy of Albert L. Rhoton Jr., MD: an analysis of transition and evolution over 50 years

J Neurosurg 129:1331–1341, 2018

Dr. Albert L. Rhoton Jr. was a pioneer of the study of microneurosurgical anatomy. Championing this field over the past half century, he produced more than 500 publications.

In this paper, the authors review his body of work, focusing on approximately 160 original articles authored by Rhoton and his microneuroanatomy fellows.

The articles are categorized chronologically into 5 stages: 1) dawn of microneurosurgical anatomy, 2) study of basic anatomy for general neurosurgery, 3) study for skull base surgery, 4) study of the internal structures of the brain by fiber dissection, and 5) surgical anatomy dealing with new advanced surgical approaches.

Rhoton introduced many new research ideas and surgical techniques and approaches, along with better microsurgery instruments, through studying and teaching microsurgical anatomy, especially during the first stage. The characteristic features of each stage are explained and the transition phases of his projects are reviewed.

 

Endoscopic transorbital superior eyelid approach: anatomical study from a neurosurgical perspective

J Neurosurg 129:1203–1216, 2017

Recent studies have proposed the superior eyelid endoscopic transorbital approach as a new minimally invasive route to access orbital lesions, mostly in otolaryngology and maxillofacial surgeries. The authors undertook this anatomical study in order to contribute a neurosurgical perspective, exploring the anterior and middle cranial fossa areas through this purely endoscopic transorbital trajectory.

METHODS Anatomical dissections were performed in 10 human cadaveric heads (20 sides) using 0° and 30° endoscopes. A step-by-step description of the superior eyelid transorbital endoscopic route and surgically oriented classification are provided.

RESULTS The authors’ cadaveric prosection of this approach defined 3 modular routes that could be combined. Two corridors using bone removal lateral to the superior and inferior orbital fissures exposed the middle and anterior cranial fossa (lateral orbital corridors to the anterior and middle cranial base) to unveil the temporal pole region, lateral wall of the cavernous sinus, middle cranial fossa floor, and frontobasal area (i.e., orbital and recti gyri of the frontal lobe). Combined, these 2 corridors exposed the lateral aspect of the lesser sphenoid wing with the Sylvian region (combined lateral orbital corridor to the anterior and middle cranial fossa, with lesser sphenoid wing removal). The medial corridor, with extension of bone removal medially to the superior and inferior orbital fissure, afforded exposure of the opticocarotid area (medial orbital corridor to the opticocarotid area).

CONCLUSIONS Along with its minimally invasive nature, the superior eyelid transorbital approach allows good visualization and manipulation of anatomical structures mainly located in the anterior and middle cranial fossae (i.e., lateral to the superior and inferior orbital fissures). The visualization and management of the opticocarotid region medial to the superior orbital fissure are more complex. Further studies are needed to prove clinical applications of this relatively novel surgical pathway.

 

Surgical outcome in smaller symptomatic vestibular schwannomas. Is there a role for surgery?

Acta Neurochirurgica (2018) 160:2263–2275

Currently, there is no consensus in the initial management of small vestibular schwannomas (VSs). They are routinely watched and/or referred for radiosurgical treatment, although surgical removal is also an option. We hereby evaluate clinical outcomes of patients who have undergone surgical removal of smaller symptomatic VSs.

Methods Patients with vestibular schwannomas (grade T1–T3b according to Hannover classification) were reviewed. Patients with symptomatic tumors who underwent surgery were evaluated. Their preoperative hearing status was based on the guideline of the committee on hearing and equilibriumof the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) foundation. Their postoperative facial nerve function, hearing status, vestibular symptoms, and degree of tumor resection were assessed.

Results Thirty patients were selected for surgery via a retrosigmoid approach based on their age, symptoms, and their own decision-making after discussion of management options. Most patients presented with hearing loss. Seventeen patients had useful hearing preoperatively. Among them, 10 patients (59%) preserved useful hearing (class A or B) postoperatively. MRI at 1-year follow-up confirmed complete resection in 26/29 patients. Also, 29 patients (97%) had HB grade I–II, and 1 patient had HB III at 1-year follow-up. Except for 1 patient with CSF leak, 1 patient with delayed facial nerve palsy, and 2 patients with asymptomatic sigmoid sinus occlusion, there were no other new morbidities.

Conclusion Although both observation and radiosurgery are valid options in the management of smaller size vestibular schwannomas, surgical treatment seems to offer a high rate of facial nerve preservation, a reasonable rate of hearing sparing, and a high total resection rate. Clinicians should consider surgical treatment as a valid option in the initial management of symptomatic small vestibular schwannomas in younger patients.

Esthesioneuroblastoma: A Patterns-of-Care and Outcomes Analysis of the National Cancer Database

Neurosurgery 83:940–947, 2018

BACKGROUND: The available literature to guide treatment decision making in esthesioneuroblastoma (ENB) is limited.

OBJECTIVE: To define treatment patterns and outcomes in ENB according to treatment modality using a large national cancer registry.

METHODS: This study is a retrospective cohort analysis of 931 patients with a diagnosis of ENB who were treated with surgery, radiation therapy, and/or chemotherapy in the United States between the years of 2004 and 2012. Log-rank statisticswere used to compare overall survival by primary treatment modality. Logistic regression modeling was used to identify predictors of receipt of postoperative radiotherapy (PORT). Cox proportional hazardsmodeling was used to determine the survival benefit of PORT. Subgroup analyses identified subgroups that derived the greatest benefit of PORT.

RESULTS: Primary surgery was the most common treatment modality (90%) and resulted in superior survival compared to radiation (P < .01) or chemotherapy (P < .01). On multivariate analysis, PORT was associated with decreased risk of death (hazard ratio [HR] 0.53, P<.01). PORT showed a survival benefit in Kadish stage C (HR 0.42, P<.01) and D (HR 0.09, P = .01), but not Kadish A (HR 1.17, P = .74) and B (HR 1.37, P = .80). Patients who received chemotherapy derived greater benefit from PORT (HR 0.22, P < .01) compared with those who did not (HR 0.68, P=.13). Predictors of PORT included stage, grade, extent of resection, and chemotherapy use.

CONCLUSION: Best outcomes were obtained in patients undergoing primary surgery. The benefit of PORT was driven by patients with stages C and D disease, and by those also receiving chemotherapy.

 

Telemetry in intracranial pressure monitoring: sensor survival and drift

Acta Neurochirurgica (2018) 160:21372144

Telemetric intracranial pressure (ICP) monitoring enable long-term ICP monitoring on patients during normal day activities and may accordingly be of use during evaluation and treatment of complicated ICP disorders. However, the benefits of such equipment depend strongly on the validity of the recordings and how often the telemetric sensor needs to be re-implanted. This study investigates the clinical and technical sensor survival time and drift of the telemetric ICP sensor: Raumedic Neurovent-P-tel.

Methods Implanted telemetric ICP sensors in the period from January 2011 to December 2017 were identified, and medical records reviewed for complications, explantation reasons, and parameters relevant for determining clinical and technical sensor survival time. Explanted sensors were tested in an experimental setup to study baseline drift.

Results In total, implantation of 119 sensors were identified. Five sensors (4.2%) were explanted due to skin dResultsamage, three (2.5%) due to wound infection, and two (1.7%) due to ethylene oxide allergy. No other complications were observed. The median clinical sensor survival time was 208 days (95% CI 150–382). The median technical sensor survival time was 556 days (95% CI 382–605). Explanted sensors had a median baseline drift of 2.5 mmHg (IQR 2.0–5.5).

Conclusion In most cases, the ICP sensor provides reliable measurements beyond the approved implantation time of 90 days. Thus, the sensor should not be routinely removed after this period, if ICP monitoring is still indicated. However, some sensors showed technical malfunction prior to the CE-approval, underlining that caution should always be taken when analyzing telemetric ICP curves.

 

Image-Guided Robotic Radiosurgery for Trigeminal Neuralgia

Neurosurgery 83:1023–1030, 2018

Frameless, non-isocentric irradiation of an extended segment of the trigeminal nerve introduces new concepts in stereotactic radiosurgery for medically resistant trigeminal neuralgia (TN).

OBJECTIVE: To report the results of the largest single-center experience about imageguided robotic radiosurgery for TN.

METHODS: A cohort of 138 patients treated with CyberKnife®  (Accuray Incorporated, Sunnyvale, California) radiosurgery with a minimum follow-up of 36 mo were recruited. Pain relief, medications, sensory disturbances, rate and time of pain recurrence were prospectively analyzed.

RESULTS: Median follow-up was 52.4 mo; median dose 75 Gy; median target length 5.7- mm; median target volume 40 mm3; median prescription dose 60 Gy (80% isodose line). Actuarial pain control rate (Barrow Neurological Institute [BNI] class I-IIIa) at 6, 12, 24, and 36 mo were 93.5%, 85.8%, 79.7%, and 76%, respectively. Overall, 33 patients (24%) required a second treatment. Overall, 18.1% developed sensory disturbances after 16.4 ± 8.7 mo. One patient (0.7%) developed BNI grade IV dysfunction; 6 (4.3%) developed BNI grade III (somewhat bothersome) hypoesthesia after retreatment; BNI grade II (not bothersome) hypoesthesia was reported by 18 patients (11 after retreatment). Shorter nerve length (<6mmvs 6 mm), smaller nerve volume (<30mm3 vs>30mm3), and lower prescription dose (<58 vs>58 Gy) were associated with treatment failure (P=.01, P=.02, P=.03, respectively). Re-irradiation independently predicted sensory disturbance (P < .001).

CONCLUSION: Targeting a 6-mm segment of the trigeminal nerve with a prescribed dose of 60 Gy appears safe and effective. Persistent pain control was achieved in most patients with acceptable risk of sensory complications, which were typically found after re-irradiation.

KEYWORDS: Trigeminal neuralgia, Pain, Stereotactic radiosurgery, Robotic, Image-guided, CyberKnife

 

Long-Term Outcome Following Stereotactic Radiosurgery for Glomus Jugulare Tumors

Neurosurgery 83:1007–1014, 2018

Glomus jugulare tumors (GJTs) are rare benign tumors, which pose significant treatment challenges due to proximity to critical structures.

OBJECTIVE: To evaluate the long-term clinical and radiological outcomein patients undergoing stereotactic radiosurgery (SRS) for GJTs through retrospective study.

METHODS: Forty-two patientswith 43 GJTswere treated using Gamma Knife radiosurgery (GKRS; Elekta AB, Stockholm, Sweden) at our institute from 1997 to 2016. Clinical, imaging, and radiosurgery data were collected from an institutional review board approved database.

RESULTS: Most patients were females (n = 35, 83.3%) and median age was 61 yr (range 23- 88 yr).Median tumor volume and diameterwere 5 cc and 3 cm, respectively,with a median follow-up of 62.3 mo (3.4-218.6 mo). Overall, 20 patients (47.6%) improved clinically and 14 (33.3%) remained unchanged at last follow-up. New onset or worsening of hearing loss was noted in 6 patients (17.2%) after SRS. The median prescription dose to the tumor margin was 15 Gy (12-18 Gy). Median reduction in tumor volume and maximum tumor diameter at last follow-up was 33.3% and 11.54%, respectively. The 5-yr and 10-yr tumor control rates were 87%±6% and 69%±13%, respectively. There was no correlation between maximum or mean dose to the internal acoustic canal and post-GK hearing loss (P > .05).

CONCLUSION: SRS is safe and effective in patients with GJTs and results in durable, longterm control. SRS has lower morbidity than that associated with surgical resection, particularly lower cranial nerve dysfunction, and can be a first-line management option in these patients.

Supratotal Resection of Diffuse Frontal Lower Grade Gliomas with Awake Brain Mapping, Preserving Motor, Language, and Neurocognitive Functions

World Neurosurg. (2018) 119:3039

Extended margin tumor resection beyond the abnormal area detected by magnetic resonance imaging, defined as supratotal resection, could improve the out- comes of patients with lower grade gliomas (LGGs). The aim of the present study was to assess the surgical outcomes of awake brain mapping to achieve supratotal resection with determination of the normal brain tissue boundaries beyond the tumor of frontal LGGs, in both dominant and nondominant hemispheres.

METHODS: We analyzed the data from 9 patients with diffuse frontal LGGs who had undergone supratotal resection with awake surgery from January 2016 to November 2017.

RESULTS: The frontal aslant tract was identified as the functional boundary in 4 of 5 left frontal tumor cases (80%). Working memory impairments during dorsolateral prefrontal cortex stimulation with digit span and/or visual N-back tasks were detected in all 4 patients (100%) with right-frontal tumor. The neurocognitive outcomes were significantly improved after surgery, as shown by the mean Wechsler adult intelligence scale III scores for verbal in- telligence quotient (P [ 0.04) and verbal comprehension (P [ 0.03) and the mean Wechsler memory scale-revised scores for generalized memory (P [ 0.04) and delayed recall (P [ 0.04).

CONCLUSIONS: The results of the present study have provided evidence that awake mapping can enable the preservation of higher neurocognitive function, including working memory and spatial cognition in patients with nondominant right frontal tumors. Despite the small number of cases, our findings suggest the surgical benefit of awake surgery for supratotal resection of diffuse frontal LGGs.

Conscious sedation with dexmedetomidine compared with asleep-awake-asleep craniotomies in glioma surgery

J Neurosurg 129:1223–1230, 2018

Awake craniotomies have become a feasible tool over time to treat brain tumors located in eloquent regions. Different techniques have been applied in neurooncology centers. Both “asleep-awake-asleep” (asleep) and “conscious sedation” were used subsequently at the authors’ neurosurgical department. Since 2013, the authors have only performed conscious sedation surgeries, predominantly using the alfa2-receptor agonist dexmedetomidine as the anesthetic drug. The aim of this study was to compare both mentioned techniques and evaluate the clinical use of dexmedetomidine in the setting of awake craniotomies for glioma surgery.

METHODS The authors retrospectively analyzed patients who underwent operations either under the asleep condition using propofol-remifentanil or under conscious sedation conditions using dexmedetomidine infusions. In the asleep group patients were intubated with a laryngeal mask and extubated for the assessment period. Adverse events, as well as applied drugs with doses and frequency of usage, were recorded.

RESULTS From 224 awake surgeries between 2009 and 2015, 180 were performed for the resection of gliomas and included in the study. In the conscious sedation group (n = 75) significantly fewer opiates (p < 0.001) and vasoactive (p < 0.001) and antihypertensive (p < 0.001) drugs were used in comparison with the asleep group (n = 105). Furthermore, the postoperative length of stay (p < 0.001) and the surgical duration (p < 0.001) were significantly lower in the conscious sedation group.

CONCLUSIONS Use of dexmedetomidine creates excellent conditions for awake surgeries. It sedates moderately and acts as an anxiolytic. Thus, after ceasing infusion it enables quick and reliable clinical neurological assessment of patients. This might lead to reducing the amount of administered antihypertensive and vasoactive drugs as well as the length of hospitalization, while likely ensuring more rapid surgery.

 

Decision Making in theWait-and-Scan Approach for Vestibular Schwannomas: Is There a Price to Pay in Terms of Hearing, Facial Nerve, and Overall Outcomes?

Neurosurgery 83:858–870, 2018

The wait-and-scan modality has emerged as an important strategy in the management of vestibular schwannoma (VS) as it has been demonstrated that many tumors grow slowly or do not show any growth over long periods.

OBJECTIVE: To analyze long-term outcomes of wait-and-scan in the treatment of patients with VS, discuss the factors contributing to the decision making, determine the inherent risks of the policy, and compare our results with literature.

METHODS: In total, 576 patients with sporadic unilateral VS who were managed with wait-and-scan were reviewed retrospectively. Of these, a subset of 154 patients with 5-yr follow-up was separately analyzed. The tumor characteristics including patterns of growth, rate of growth, hearing outcomes, and likely factors affecting the above parameters were analyzed.

RESULTS: The mean period of follow-up was 36.9 ± 30.2 mo. The mean age was 59.2 ± 11.6 yr. Thirteen different patterns of tumor growth were observed. Eighty-four (54.5%) of 154 tumors with 5-yr follow-up showed no growth throughout 5 yr. Fifty-six (36.4%) tumors showedmixed growth rates. Only 57 (37%) patients had serviceable hearing at the start of follow-up, but 32 (56.1%) maintained it at the end of follow-up. One hundred fifty (26%) of the 576 patients who failed wait-and-scan had to be taken up for surgery.

CONCLUSION: While there may be no price to pay in wait-and-scan as far as hearing is concerned, this may not be the case for facial nerve outcomes, wherein the results may be better if the patients are taken earlier for surgery.

Outcomes of Operative Treatment for Adult Cervical Deformity

Neurosurgery 83:1031–1039, 2018

Despite the potential for profound impact of adult cervical deformity (ACD) on function and health-related quality of life (HRQOL), there are few high-quality studies that assess outcomes of surgical treatment for these patients.

OBJECTIVE: To determine the impact of surgical treatment for ACD on HRQOL.

METHODS: We conducted a prospective cohort study of surgically treated ACD patients eligible for 1-yr follow-up. Baseline deformity characteristics, surgical parameters, and 1-yr HRQOL outcomes were assessed.

RESULTS: Of 77 ACD patients, 55 (71%) had 1-yr follow-up (64% women, mean age of 62 yr, mean Charlson Comorbidity Index of 0.6, previous cervical surgery in 47%). Diagnoses included cervical sagittal imbalance (56%), cervical kyphosis (55%), proximal junctional kyphosis (7%) and coronal deformity (9%). Posterior fusion was performed in 85% (mean levels = 10), and anterior fusion was performed in 53% (mean levels = 5). Three-column osteotomy was performed in 24%of patients.One year following surgery, ACD patients had significant improvement in Neck Disability Index (50.5 to 38.0, P<.001), neck pain numeric rating scale score (6.9 to 4.3, P<.001), EuroQol 5 dimension (EQ-5D) index (0.51 to 0.66, P< .001), and EQ-5D subscores: mobility (1.9 to 1.7, P=.019), usual activities (2.2 to 1.9, P=.007), pain/discomfort (2.4 to 2.1, P < .001), anxiety/depression (1.8 to 1.5, P = .014).

CONCLUSION: Based on a prospective multicenter series of ACD patients, surgical treatment provided significant improvement in multiple measures of pain and function, including Neck Disability Index, neck pain numeric rating scale score, and EQ-5D. Further follow-up will be necessary to assess the long-term durability of these improved outcomes.

 

Impact of aneurysm shape on morbidity after clipping of unruptured intracranial aneurysms

Acta Neurochirurgica (2018) 160:2169–2176

Complex aneurysm shape is a predominant risk factor for aneurysm rupture but its impact on clinical outcome after clipping remains unclear. The objective of the present study was to compare complications and morbidity after clipping of unruptured single-sac aneurysms (SSAs) and aneurysms with multiple sacs (MSAs).

Methods A retrospective, single-center study was conducted for patients that were treated between 2010 and 2018. We analyzed
surgical parameters, treatment-related complications, and morbidity, defined as any increase in the modified Rankin scale at 3-
month follow-up.

Results We identified 101 patients (mean age: 52.9 ± 10.5 years) that underwent clipping for 57 SSAs and 44 MSAs. The two
groups were comparable regarding aneurysm size and neck width. Clipping of MSAs was associated with a longer operation time
(p = 0.008) and increased use of intraoperative indocyanine green (p = 0.016) than SSAs. Complications occurred more often in
the MSA group (29.5%) than in the SSA group (14.0%; p = 0.057). Morbidity was significantly higher in the MSA group
(20.5%) than in the SSA group (3.5%, p = 0.009). In the univariate analysis, the odds of morbidity were 7.1 times greater for
MSAs than for SSAs (95% CI 1.4–34.7).

Conclusions Morbidity after microsurgical clipping is significantly increased in MSAs as compared to SSAs. This may be
attributed to a more difficult clip placement with stronger manipulation of the aneurysm dome and the surrounding brain tissue.