Refractory inflammatory hydrocephalus: A case report of a rare and complicated delayed sequelae following cerebral hemispherectomy surgery for epilepsy.

Hydrocephalus is a known complication following surgical resection of a cerebral hemisphere for refractory epilepsy, yet the pathological mechanism remains poorly understood. We present a case of refractory aseptic inflammatory hydrocephalus following cerebral hemispherectomy surgery for refractory epilepsy treated with a combination of cerebral spinal fluid (CSF) diversion and immunosuppression via IL-1 receptor agonist, Anakinra. At 6 month follow up, the patient had returned to neurologic baseline, with improvement in school and physical therapy performance. Further investigation into the beneficial role of immunosuppressive therapy is needed to better understand the relationship between neuro-inflammation and improving outcomes following epilepsy surgery.

Radiographic Alignment Parameters for Lumbosacral Reconstruction in Patients With Altered S1 Morphology.

STUDY DESIGN: Retrospective quantitative analysis study. OBJECTIVES: Pelvic incidence has been established as central radiographic marker which determines patient-specific correction goals during surgery for adult spinal deformity. In cases with sacral doming or sacral osteotomy where the PI cannot be calculated, reliable radiographic parameters need to be established to determine surgical goals. We aim to determine multiple radiographic parameters and formulas that can be utilized when the S1 superior endplate is obscured. METHODS: Retrospective analysis was performed on 68 healthy volunteers without prior spine surgery with full-length radiographs. Pelvic incidence, sacral slope, and pelvic tilt were calculated for each patient. Additional measurements such as L4, L5, and S2 incidence, tilt, and slope were collected. A new radiographic parameter defined as the L4-Sciatic notch angle was measured. Regression analysis was performed on each value to determine its relationship with S1 based incidence, tilt, and slope. RESULTS: Mean values for L5 incidence, L4 incidence, and L4 sciatic notch angle were 21.8° ± 8.9, 4.4° ± 8.1, and 44.4° ± 12, respectively. The linear regression analysis produced the following formulas which can be utilized to determine deformity correction goals when pelvic incidence can be calculated pre-operatively: L5i = .65*S1i-11.4, L4i = .44*S1i-18.6, and L4SNA = -.34*S1i + 66.5. In settings where pelvic incidence cannot be calculated, the following formulas can be utilized: L5i = .66*S2i-32.3 and L4SNA = -.02*S2i2 + 1.1*S2i + 63.5. P-values for all regression analyses were <.001. CONCLUSION: This study provides target radiographic alignment values that can be utilized for patients with either pre-operative altered S1 endplates or in cases with intraoperative alteration of S1 (sacral osteotomy).

Exoscopic Retrosigmoid Approach for an Anteromedial Tentorial Meningioma: 2D Operative Video.

We present a 2-dimensional operative video (Video 1) of a suboccipital retrosigmoid approach for an anteromedial tentorial meningioma with a specific focus on the use of a surgical exoscope. The patient is a 50-year-old woman who presented to emergency room with a 6-month history of nausea, dizziness, and gait imbalance secondary to a 2.5-cm homogenously enhancing mass originating from the anteromedial tentorium on the right side with associated brainstem compression. Retrosigmoid craniotomy was selected due to the favorable surgical corridor for resection and lower risk of cerebrospinal fluid leak, hearing loss, and seizures compared with other approaches.1-5 The patient consented to the procedure. Video 1 emphasizes the advantages of the exoscope compared with the microscope in optimizing surgeon efficiency, ergonomics, and comfort.6 The unique operating room setup associated with exoscope use is highlighted. The patient underwent uncomplicated gross total resection with a mild trochlear nerve palsy noted postoperatively that was resolved at follow-up.7.

T1 Pedicle Subtraction Osteotomy With Subaxial Cervical Pedicle Screw Fixation.

Patients suffering from ankylosing spondylitis are not only predisposed to the development of rigid cervicothoracic deformities but are also at an increased risk of cervical fractures. Deformity correction and stabilization are particularly challenging in this patient population due to the brittle bone quality and low bone mineral density. Thoracic pedicle subtraction osteotomy is a workhorse approach for the correction of focal severe kyphotic deformity with lower complication rates than 3-column osteotomy. Successful execution of an upper thoracic PSO requires careful presurgical planning as well as anticipation of the patient's postoperative needs. Here, we describe the use of a T1 PSO in the correction of a rigid cervicothoracic chin-on-chest deformity in a patient with AS. The risk of implant failure was reduced by the use of a multi-rod construct, navigated cervical pedicle screws, and dual-pitched thoracic pedicle screws.

Exoscopic supraorbital approach for a suprasellar craniopharyngioma.

The authors present an operative video of a supraorbital craniotomy for resection of a suprasellar, supradiaphragmatic craniopharyngioma. The patient is a 62-year-old female who presented with 3 months of blurry vision secondary to a 2.5-cm suprasellar mass causing compression on the optic nerve. Supraorbital craniotomy was selected due to the supradiaphragmatic location of the tumor and the subsequent disadvantages, including CSF leakage, of other approaches such as the endoscopic endonasal approach. The operative video emphasizes optimizing operating room (OR) setup to improve surgeon ergonomics and comfort. The patient underwent an uncomplicated gross-total resection with subsequent discharge home the day after surgery. The video can be found here: https://stream.cadmore.media/r10.3171/2023.10.FOCVID23140.

Effectiveness of Continuous Hypertonic Saline in Acute Ischemic Infarcts: A Radiographic and Clinical Evaluation.

OBJECTIVE: The role of continuous hypertonic saline (HS) infusion in the management of malignant cerebral edema is controversial. We evaluated patients presenting with large anterior circulation territory infarcts and compared radiographic and clinical outcomes to evaluate the effects of continuous HS. METHODS: This was a retrospective review of patients with malignant ischemic strokes who were initially managed with continuous HS versus routine medical management. Radiographic parameters of cerebral edema and clinical parameters were collected at different time intervals after admission. Rates and timing of surgery, mortality, and complications were also collected. RESULTS: The study included 43 patients: 26 in group 1 (HS) and 17 in group 2 (no HS). Both cohorts had comparable baseline clinical and radiographic parameters. There was no difference between rates and timing of surgery, complications, and mortality. Mean midline shift was significantly greater in the HS group at interval 1 (12-36 hours, P = 0.003) and interval 2 (36-60 hours, P = 0.030), and mean change in midline shift from initial interval to interval 1 was significantly greater in the HS group (P = 0.019). CONCLUSIONS: Despite the widespread use of continuous HS in acute ischemic infarcts, only a limited number of studies have evaluated its efficacy, and virtually no studies have studied its effect on radiographic progression and rates of decompressive surgery. Results of this study indicate that there is no benefit of continuous HS. In fact, there may be worsening of cerebral edema with administration of continuous HS. In addition, there are no differences in prevention or delay of decompressive surgery or in overall mortality.

Factors associated with adjacent-level tumor progression in patients receiving surgery followed by radiosurgery for metastatic epidural spinal cord compression.

OBJECTIVE: Separation surgery followed by spine stereotactic radiosurgery (SSRS) has been shown to achieve favorable rates of local tumor control and patient-reported outcomes in patients with metastatic epidural spinal cord compression (MESCC). However, rates and factors associated with adjacent-level tumor progression (ALTP) in this population have not yet been characterized. The present study aimed to identify factors associated with ALTP and examine its association with overall survival (OS) in patients receiving surgery followed by radiosurgery for MESCC. METHODS: Thirty-nine patients who underwent separation surgery followed by SSRS for MESCC were identified using a prospectively collected database and were retrospectively reviewed. Radiological measurements were collected from preoperative, postoperative, and post-SSRS MRI. Statistical analysis was conducted using the Kaplan-Meier product-limit method and Cox proportional hazards test. Subgroup analysis was conducted for patients who experienced ALTP into the epidural space (ALTP-E). RESULTS: The authors' cohort included 39 patients with a median OS of 14.7 months (range 2.07-96.3 months). ALTP was observed in 16 patients (41.0%) at a mean of 6.1 ± 5.4 months postradiosurgery, of whom 4 patients (10.3%) experienced ALTP-E. Patients with ALTP had shorter OS (13.0 vs 17.1 months, p = 0.047) compared with those without ALTP. Factors associated with an increased likelihood of ALTP included the amount of bone marrow infiltrated by tumor at the index level, amount of residual epidural disease following separation surgery, and prior receipt of radiotherapy at the index level (p < 0.05). Subgroup analysis revealed that primary tumor type, amount of preoperative epidural disease, time elapsed between surgery and radiosurgery, and prior receipt of radiotherapy at the index level were significantly associated with ALTP-E (p < 0.05). CONCLUSIONS: To the authors' knowledge, this study is the first to identify possible risk factors for ALTP, and they suggest that it may be associated with shorter OS in patients receiving surgery followed by radiosurgery for MESCC. Future studies with higher power should be conducted to further characterize factors associated with ALTP in this population.

Reducing Wrong-level Spinal Surgeries Through Root Cause Analyses: A 10-year Longitudinal Analysis of a Single Tertiary Institution's Iterative Policy Improvements.

MINI: This study is a comprehensive narrative of all wrong-level spine surgeries and prevention strategies employed at our institution between 2008 and 2019, and aims to provide a roadmap for developing a rigorous prevention protocol. We systematically track root cause analyses and policy changes to determine which prevention strategies are most effective.

Retrospective review. We aim to create a comprehensive narrative of all wrong-level spinal surgeries (WLSS) and subsequent prevention strategies employed at our institution and provide a roadmap for developing a rigorous prevention protocol. There is currently no published evidence-based protocol to prevent WLSS. Previous studies are limited to multi-institution surgeon surveys and opinion pieces; the impact of serial interventions to eliminate WLSS is lacking. No studies have longitudinally analyzed a single institution's serial root cause analyses (RCA) of individual WLSS cases and the stepwise impact of targeted interventions to reduce WLSS occurrence. We reviewed all wrong-site spine surgeries and prevention strategies employed at our institution between 2008 and 2019, and corresponding WLSS-related RCAs were collected from institutional records. We conducted a longitudinal analysis of these reports and tracked policy implementations that resulted along with the incidence of WLSS following each policy. Fifteen WLSS were identified with 13 corresponding RCAs of 21,179 spine surgeries between 2008 and 2019. Three policy categories emerged: imaging, operating room (OR) culture, and vertebral body marking. The salient changes from each category were: requiring two immovable vertebral markers (2013); requiring intraoperative radiographs with markers and retractors positioned (2014); open-ended questioning during spinal level verification by residents and fellows (2015); and requiring an impartial radiologist to have verbal contact with the operating surgeon intraoperatively to collaboratively discuss localization (2018). Each change resulted in WLSS incidence decline (five in 2014, three in 2015, 0 in 2019). Stepwise process improvement based on WLSS case review is necessary, as no one change in standard operating procedure effectively eliminated WLSS. Improvements in communication between OR staff, surgeon, and radiologist, as well as intraoperative imaging and marking optimization all contributed to improvements in WLSS rates. By focusing on lessons learned from RCAs using this methodology, institutions can iteratively improve rates of WLSS. Level of Evidence: 4.