Clinical Outcomes and Radiographic Results of Prone Transpsoas Lateral Lumbar Interbody Fusion: A Single-Institution Case Series.

BACKGROUND AND OBJECTIVES: This study assessed feasibility, radiologic parameters, and clinical outcomes in patients who underwent the prone transpsoas (PTP) approach for lateral lumbar interbody fusion. METHODS: This retrospective observational study included consecutive patients who underwent PTP performed by a single surgeon. Data were collected including age, sex, body mass index, operative levels, retraction time, complications, radiographic measurements, and visual analog scale pain scores. Statistical analyses were performed using nonparametric Wilcoxon 2-sample tests. RESULTS: A total of 106 consecutive patients (mean [SD] age, 66 [15] years; mean [SD] body mass index, 29.3 [5.0]) underwent PTP on 173 spinal levels, with a mean (SD) follow-up of 13 (8) months. Sixty of 106 (57%) patients underwent a 1-level PTP procedure (range, 1-4 levels), most commonly on L4-5. The mean (SD) retraction time was 10.4 (3.1) minutes for L1-2, 9.7 (2.8) minutes for L2-3, 9.3 (2.3) minutes for L3-4, and 9.5 (3.2) minutes for L4-5. Adverse events included incidental anterior longitudinal ligament release (3 of 173 [2%] levels) and transient ipsilateral hip flexor weakness (1 of 106 [0.9%] patients). The mean pelvic incidence was 57°. Lumbar lordosis increased from a mean of 44° to 51° (P < .001). Pelvic tilt decreased from a mean of 20° to 12° (P < .001). Pelvic incidence-lumbar lordosis mismatch decreased from a mean of 13 to 5 (P < .001). Visual analog scale pain scores improved from a mean of 6 preoperatively to 5 postoperatively (P < .001). CONCLUSION: In this single-institution patient series, the PTP approach was effective and safe for lateral lumbar fusion, with minimal complications and improved lumbar lordosis and patient-reported pain outcomes.

Two-Level Anterior Cervical Discectomy and Fusion Performed Using a Three-Dimensional Exoscope.

Anterior cervical discectomy and fusion (ACDF) is a common neurosurgical procedure. Portions of the procedure, such as the discectomy, foraminotomy, graft placement, and plate placement, are often performed using operating microscopes to maximize visualization and minimize neurovascular injury. Although standard operating microscopes offer superb visualization, they lack ergonomic and educational utility. With modern advancements in digital imaging and stereopsis, there has been a surge of interest in evaluating modern exoscopes for their utility in cranial and spinal neurosurgery.1-3 In Video 1, we demonstrate the use of a commercial three-dimensional exoscope from skin incision through completion of a two-level ACDF. Both the lead surgeon and the assistant surgeon were able to maintain a neutral, ergonomic, and comfortable position throughout the surgery. Furthermore, we tested the utility of this technique in 15 patients undergoing ACDF (2 one-level, 9 two-level, 3 three-level, and 1 four-level). Mean (SD) overall operative time was 118 (34) minutes (2-level ACDF, 110 [12] minutes), and mean (SD) blood loss was 23 (8.0) mL. The Neck Disability Index score and visual analog scale score for neck pain improved significantly at 6 weeks postoperatively (from 59.6 [1.3] to 27.9 [3.0] and from 6.3 [1.0] to 2.5 [0.92], respectively; P < 0.001 for both). Thus, excellent clinical outcomes can be achieved using three-dimensional exoscopes with comparable operative time and blood loss compared with conventional surgical microscopes or loupes. Given the improved ergonomic and teaching potential of exoscopes, the use of three-dimensional exoscopes for neurosurgical and spine surgeries warrants further investigation.

Novel Use of Bilateral Prone Transpsoas Approach for the Treatment of Transforaminal Interbody Fusion Pseudarthrosis and Interbody Cage Subsidence.

BACKGROUND AND OBJECTIVES: Pseudarthrosis is a complication after transforaminal lumbar interbody fusion (TLIF) that leads to recurrent symptoms and potential revision surgery. Subsidence of the interbody adds to the complexity of surgical revision. In addition, we report a novel technique for the treatment of TLIF pseudarthrosis with subsidence and propose an approach algorithm for TLIF cage removal. METHODS: Cases of reoperation for TLIF pseudarthrosis were reviewed. We report a novel technique using a bilateral prone transpsoas (PTP) approach to remove a subsided TLIF cage and place a new lateral cage. An approach algorithm was developed based on the experience of TLIF cage removal. The patient was placed in the prone position with somatosensory evoked potential and electromyography monitoring. A PTP retractor was placed using standard techniques on the ipsilateral side of the previous TLIF. After the discectomy, the subsided TLIF cage was visualized but unable to be removed. The initial dilator was closed, and a second PTP retractor was placed on the contralateral side. After annulotomy and discectomy to circumferentially isolate the subsided cage, a box cutter was used to push and mobilize the TLIF cage from this contralateral side, which could then be pulled out from the ipsilateral side. A standard lateral interbody cage was then placed. RESULTS: Retractor time was less than 10 minutes on each side. The patient's symptoms resolved postoperatively. We review illustrative cases of various approaches for TLIF cage removal spanning the lumbosacral spine and recommend an operative approach based on the lumbar level, degree of subsidence, and mobility of the interbody. CONCLUSION: Bilateral PTP retractors for TLIF cage removal may be effectively used in cases of pseudarthrosis with severe cage subsidence. Careful consideration of various factors, including patient surgical history, body habitus, and intraoperative findings, is essential in determining the appropriate treatment for these complex cases.

Dehydrated human amnion/chorion membrane use in emergent craniectomies shows minimal dural adhesions.

Decompressive craniectomies (DCs) are routinely performed neurosurgical procedures to emergently treat increased intracranial pressure secondary to multiple aetiologies, such as subdural haematoma, epidural haematoma, or malignant oedema in the setting of acute infarction. The DC procedure typically induces epidural fibrosis post-cranial resection, resulting in adherence of the dura to both the brain internally and skin flap externally. This becomes especially problematic in the setting of skull flap replacement for cranioplasty as adherences can lead to bridging vein tear, damage to the underlying brain cortex, and other postoperative complications. Dural adjuvants, which can contribute to decreased rate of adherence formation, can thereby reduce both postoperative cranioplasty complications and operative duration. Dehydrated human amnion/chorion membrane (DHACM) allografts (AMNIOFIX, MIMEDX Group Inc., US) have been shown to reduce the rate of dural scar tissue formation in re-exploration of posterior lumbar interbody fusion operations which require entry into the epidural space. The purpose of this study was to evaluate whether or not the use of DHACM in the setting of emergent craniectomies decreased the rate of dural adhesion formation and subsequent cranioplasty complications. Patients (n=7) who underwent emergent craniectomy and intraoperative placement of DHACM were evaluated during replacement of either an autologous skull cap or a custom-made implant, at which point the degree of adhesions was qualitatively assessed. Placement of DHACM below and on top of the dura resulted in negligible adhesion being found during the defect exposure, and there were no intraoperative complications during cranioplasties. Reported estimated blood loss across the seven patients averaged 64.2ml, total operative time averaged 79.2 minutes, and time dedicated to exposing defect for bone flap placement was <3 minutes.

Complications of the Prone Transpsoas Lateral Lumbar Interbody Fusion for Degenerative Lumbar Spine Disease: A Multicenter Study.

BACKGROUND AND OBJECTIVES: The prone transpsoas (PTP) approach for lateral lumbar interbody fusion (LLIF) is a novel technique for degenerative lumbar spine disease. However, there is a paucity of information in the literature on the complications of this procedure, with all published data consisting of small samples. We aimed to report the intraoperative and postoperative complications of PTP in the largest study to date. METHODS: A retrospective electronic medical record review was conducted at 11 centers to identify consecutive patients who underwent LLIF through the PTP approach between January 1, 2021, and December 31, 2021. The following data were collected: intraoperative characteristics (operative time, estimated blood loss [EBL], intraoperative complications [anterior longitudinal ligament (ALL) rupture, cage subsidence, vascular and visceral injuries]), postoperative complications, and hospital stay. RESULTS: A total of 365 patients were included in the study. Among these patients, 2.2% had ALL rupture, 0.3% had cage subsidence, 0.3% had a vascular injury, 0.3% had a ureteric injury, and no other visceral injuries were reported. Mean operative time was 226.2 ± 147.9 minutes. Mean EBL was 138.4 ± 215.6 mL. Mean hospital stay was 2.7 ± 2.2 days. Postoperative complications included new sensory symptoms-8.2%, new lower extremity weakness-5.8%, wound infection-1.4%, cage subsidence-0.8%, psoas hematoma-0.5%, small bowel obstruction and ischemia-0.3%, and 90-day readmission-1.9%. CONCLUSION: In this multicenter case series, the PTP approach was well tolerated and associated with a satisfactory safety profile.

Radiographic alignment outcomes after the single-position prone transpsoas approach: a multi-institutional retrospective review of 363 cases.

OBJECTIVE: The aim of this paper was to evaluate the changes in radiographic spinopelvic parameters in a large cohort of patients undergoing the prone transpsoas approach to the lumbar spine. METHODS: A multicenter retrospective observational cohort study was performed for all patients who underwent lateral lumber interbody fusion via the single-position prone transpsoas (PTP) approach. Spinopelvic parameters from preoperative and first upright postoperative radiographs were collected, including lumbar lordosis (LL), pelvic incidence (PI), and pelvic tilt (PT). Functional indices (visual analog scale score), and patient-reported outcomes (Oswestry Disability Index) were also recorded from pre- and postoperative appointments. RESULTS: Of the 363 patients who successfully underwent the procedure, LL after fusion was 50.0° compared with 45.6° preoperatively (p < 0.001). The pelvic incidence-lumbar lordosis mismatch (PI-LL) was 10.5° preoperatively versus 2.9° postoperatively (p < 0.001). PT did not significantly change (0.2° ± 10.7°, p > 0.05). CONCLUSIONS: The PTP approach allows significant gain in lordotic augmentation, which was associated with good functional results at follow-up.

Chopping techniques in cataract surgery.

PURPOSE OF REVIEW: To explain reasons for phaco chop, outline strategies for transitioning to chop, and summarize recent articles discussing chopping techniques. RECENT FINDINGS: New variations of phaco chop may help with managing dense cataracts. Studies generally continue to show similar phaco time between traditional manual chopping and femtosecond laser-assisted cataract surgery. A nitinol ring prechopper compresses the lens similarly to horizontal chopping, which may reduce phaco energy for certain cases. SUMMARY: Both vertical and horizontal chopping continue to demonstrate multiple advantages over other nucleus disassembly techniques.

Pyoderma Gangrenosum Masquerading as Wound Infection in the Early Postoperative Period After Lumbar Spine Deformity Correction Surgery.

The development of pyoderma gangrenosum (PG) after surgical site trauma is a rare, poorly understood immunologic phenomenon. PG is an immunologic disorder characterized by lymphocytic infiltration of the dermis that can manifest with skin necrosis and ulceration. This rare phenomenon can mimic surgical site infection (SSI) when it occurs in the perioperative period and in the region of surgical wounds. Within the neurosurgical literature, only two cases of postoperative PG have been reported to our knowledge. We describe the clinical features and treatment of PG in the case of a 65-year-old man who underwent a three-stage surgical approach for intractable mechanical low back pain on hospital days (HDs) 1 and 2, and who subsequently developed PG around all three surgical sites in the immediate postoperative period (HD 8). The physical and laboratory findings and surgical and pharmacologic treatments are detailed. The patient was initially treated for presumed SSI, started on broad-spectrum antibiotics, and underwent surgical wound debridement twice, without resolution of symptoms. The diagnosis of PG was ultimately made by a consulting dermatologist on HD 17. The patient was started on systemic immunosuppression with steroids during his initial hospitalization; symptoms resolved within two weeks of the index surgery. Although PG is a rare entity, we suggest that it be considered in the differential diagnosis of nonhealing surgical wounds. Familiarity with PG may help mitigate unnecessary surgical morbidity and reduce the length of hospital stays and unnecessary use of antibiotics.

A Retrospective Analysis of the L3-L4 Disc and Spinopelvic Parameters on Outcomes in Thoracolumbar Fusion: Was Art Steffee Right?

OBJECTIVE: To determine whether the L3-L4 disc angle may be a surrogate marker for global lumbar alignment in thoracolumbar fusion surgery and to explore the relationship between radiographic and patient-reported outcomes after thoracolumbar fusion surgery. METHODS: Retrospective chart review was conducted on patients who had undergone a lumbar fusion involving levels from T9 to pelvis. EuroQol-Five Dimension (EQ-5D-3L) scores and adverse events including adjacent-segment disease and degeneration, pseudoarthrosis, proximal junctional kyphosis, stenosis, and reoperation were collected. Pre- and postoperative spinopelvic parameters were measured on weight-bearing radiographs, with the L3-L4 disc angle of novel interest. Univariate logistic and linear regression were performed to assess the associations of radiographic parameters with adverse event incidence and improvement in EQ-5D-3L, respectively. RESULTS: In total, 182 patients met inclusion criteria. Univariable analysis revealed that increased magnitude of L3-L4 disc angle, anterior pelvic tilt, and pelvic incidence measures are associated with increased likelihood of developing postoperative adverse events. Conversely, increased lumbar lordosis demonstrated a decreased incidence of developing a postoperative adverse event. Linear regression showed that radiographic parameters did not significantly correlate with postoperative EQ-5D-3L scores, although scores were significantly improved postfusion in all dimensions except Self-Care (P = 0.51). CONCLUSIONS: L3-L4 disc angle magnitude may serve as a surrogate marker of global lumbar alignment. The degree of spinopelvic alignment did not correlate to improvement in EQ-5D-3L score in the present study, suggesting that quality of life metric change may not be a sensitive or specific marker of postfusion alignment.

Comparison of rotational stability and repositioning rates of 2 presbyopia-correcting and 2 monofocal toric intraocular lenses.

PURPOSE: To compare the rotational stability of 2 commonly used toric presbyopia-correcting (PC) intraocular lenses (IOLs) and their monofocal toric counterparts. SETTING: Single 2-surgeon private practice. DESIGN: Retrospective study. METHODS: This study included 2 cohorts: (1) all eyes receiving a toric ReSTOR (n = 61 eyes, 49 patients) or toric Symfony (n = 779 eyes, 520 patients) IOL from September 2016 to January 2019; and (2) all eyes receiving an AcrySof (n = 2 393) or TECNIS (n = 731) monofocal toric IOL (TIOL) from April 2015 to January 2019. Eyes were only excluded if digital marking could not be used. All patients had image-guided digital marking to verify TIOL position at the conclusion of surgery. Postoperative rotation was determined by dilated examination performed later on the day of surgery or the following morning. RESULTS: The toric ReSTOR IOL was more likely to rotate 5 degrees or less than the toric Symfony IOL, 91.8% vs 79.0% (P = .01). This remained true for rotation of 10 degrees or less (100% vs 89.5%, P < 0.003). The mean rotation was 2.3 degrees for toric ReSTOR IOL compared with 4.5 for toric Symfony IOL (P = .01). Statistically significantly more eyes with toric Symfony IOL required a return to the operating room for repositioning (6.9% vs 0%, P < .03). More TECNIS monofocal TIOL eyes required surgical repositioning than AcrySof monofocal TIOL eyes (3.5% vs 1.2%, P < .001). CONCLUSIONS: Between these PC-TIOLs, the Symfony IOL was more likely to rotate and to require surgical repositioning than the ReSTOR IOL. The TECNIS TIOL built on the same platform as the Symfony IOL was more likely to require surgical repositioning than that by the AcrySof TIOL. Despite comparable rotational stability between the Symfony and TECNIS monofocal TIOLs, the Symfony was twice as likely to require surgical repositioning.

The effect of Gamma Knife radiosurgery on large posterior fossa metastases and the associated mass effect from peritumoral edema.

OBJECTIVE: Gamma Knife radiosurgery (GKRS) as monotherapy is an option for the treatment of large (≥ 2 cm) posterior fossa brain metastases (LPFMs). However, there is concern regarding possible posttreatment increase in peritumoral edema (PTE) and associated compression of the fourth ventricle. This study evaluated the effects and safety of GKRS on tumor and PTE control in LPFM. METHODS: The authors performed a single-center retrospective review of 49 patients with 51 LPFMs treated with GKRS. Patients with at least 1 clinical and radiological follow-up visit were included. Tumor, PTE, and fourth ventricle volumetric measurements were used to assess efficacy and safety. Overall survival was a secondary outcome. RESULTS: Fifty-one lesions in 49 consecutive patients were identified; 57.1% of patients were male. At the time of GKRS, the median age was 61.5 years, and the median Karnofsky Performance Status score was 90. The median number of LPFMs and overall brain metastases were 1 and 2, respectively. The median overall tumor, PTE, and fourth ventricle volumes at diagnosis were 4.96 cm3 (range 1.4-21.1 cm3), 14.98 cm3 (range 0.6-71.8 cm3), and 1.23 cm3 (range 0.3-3.2 cm3), respectively, and the median lesion diameter was 2.6 cm (range 2.0-5.07 cm). The median follow-up time was 7.3 months (range 1.6-57.2 months). At the first follow-up, 2 months posttreatment, the median tumor volume decreased by 58.66% (range -96.95% to +48.69%, p < 0.001), median PTE decreased by 78.10% (range -99.92% to +198.35%, p < 0.001), and the fourth ventricle increased by 24.97% (range -37.96% to +545.6%, p < 0.001). The local control rate at first follow-up was 98.1%. The median OS was 8.36 months. No patient required surgical intervention, external ventricular drainage, or shunting between treatment and first follow-up. However, 1 patient required a ventriculoperitoneal shunt at 23 months from treatment. Posttreatment, 65.30% received our general steroid taper, 6.12% received no steroids, and 28.58% required prolonged steroid treatment. CONCLUSIONS: In this retrospective analysis, patients with LPFMs treated with GKRS had a statistically significant posttreatment reduction in tumor size and PTE and marked opening of the fourth ventricle (all p < 0.001). This study demonstrates that GKRS is well tolerated and can be considered in the management of select cases of LPFMs, especially in patients who are poor surgical candidates.

The efficacy of intraoperative multimodal monitoring in pedicle subtraction osteotomies of the lumbar spine.

OBJECTIVE: Iatrogenic spine injury remains one of the most dreaded complications of pedicle subtraction osteotomies (PSOs) and spine deformity surgeries. Thus, intraoperative multimodal monitoring (IOM), which has the potential to provide real-time feedback on spinal cord signal transmission, has become the gold standard in such operations. However, while the benefits of IOM are well established in PSOs of the thoracic spine and scoliosis surgery, its utility in PSOs of the lumbar spine has not been robustly documented. The authors' aim was to determine the impact of IOM on outcomes in patients undergoing PSO of the lumbar spine. METHODS: All patients older than 18 years who underwent lumbar PSOs at the authors' institution from 2007 to 2017 were analyzed via retrospective chart review and categorized into one of two groups: those who had IOM guidance and those who did not. Perioperative complications were designated as the primary outcome measure and postoperative quality of life (QOL) scores, specifically the Parkinson's Disease Questionnaire-39 (PDQ-39) and Patient Health Questionnaire-9 (PHQ-9), were designated as secondary outcome measures. Data on patient demographics, surgical and monitoring parameters, and outcomes were gathered, and statistical analysis was performed to compare the development of perioperative complications and QOL scores between the two cohorts. In addition, the proportion of patients who reached minimal clinically important difference (MCID), defined as an increase of 4.72 points in the PDQ-39 score or a decrease of 5 points in the PHQ-9 score, in the two cohorts was also determined. RESULTS: A total of 95 patients were included in the final analysis. IOM was not found to significantly impact the development of new postoperative deficits (p = 0.107). However, the presence of preoperative neurological comorbidities was found to significantly correlate with postoperative neurological complications (p = 0.009). Univariate analysis showed that age was positively correlated with MCID achievement 3 months after surgery (p = 0.018), but this significance disappeared at the 12-month postoperative time point (p = 0.858). IOM was not found to significantly impact MCID achievement at either the 3- or 12-month postoperative period as measured by PDQ-39 (p = 0.398 and p = 0.156, respectively). Similarly, IOM was not found to significantly impact MCID achievement at either the 3- or 12-month postoperative period, as measured by PHQ-9 (p = 0.230 and p = 0.542, respectively). Multivariate analysis showed that female sex was significantly correlated with MCID achievement (p = 0.024), but this significance disappeared at the 12-month postoperative time point (p = 0.064). IOM was not found to independently correlate with MCID achievement in PDQ-39 scores at either the 3- or 12-month postoperative time points (p = 0.220 and p = 0.097, respectively). CONCLUSIONS: In this particular cohort, IOM did not lead to statistically significant improvement in outcomes in patients undergoing PSOs of the lumbar spine (p = 0.220). The existing clinical equipoise, however, indicates that future studies in this arena are necessary to achieve systematic guidelines on IOM usage in PSOs of the lumbar spine.

Combined use of minimal access craniotomy, intraoperative magnetic resonance imaging, and awake functional mapping for the resection of gliomas in 61 patients.

OBJECTIVECurrent management of gliomas involves a multidisciplinary approach, including a combination of maximal safe resection, radiotherapy, and chemotherapy. The use of intraoperative MRI (iMRI) helps to maximize extent of resection (EOR), and use of awake functional mapping supports preservation of eloquent areas of the brain. This study reports on the combined use of these surgical adjuncts.METHODSThe authors performed a retrospective review of patients with gliomas who underwent minimal access craniotomy in their iMRI suite (IMRIS) with awake functional mapping between 2010 and 2017. Patient demographics, tumor characteristics, intraoperative and postoperative adverse events, and treatment details were obtained. Volumetric analysis of preoperative tumor volume as well as intraoperative and postoperative residual volumes was performed.RESULTSA total of 61 patients requiring 62 tumor resections met the inclusion criteria. Of the tumors resected, 45.9% were WHO grade I or II and 54.1% were WHO grade III or IV. Intraoperative neurophysiological monitoring modalities included speech alone in 23 cases (37.1%), motor alone in 24 (38.7%), and both speech and motor in 15 (24.2%). Intraoperative MRI demonstrated residual tumor in 48 cases (77.4%), 41 (85.4%) of whom underwent further resection. Median EOR on iMRI and postoperative MRI was 86.0% and 98.5%, respectively, with a mean difference of 10% and a median difference of 10.5% (p < 0.001). Seventeen of 62 cases achieved an increased EOR > 15% related to use of iMRI. Seventeen (60.7%) of 28 low-grade gliomas and 10 (30.3%) of 33 high-grade gliomas achieved complete resection. Significant intraoperative events included at least temporary new or worsened speech alteration in 7 of 38 cases who underwent speech mapping (18.4%), new or worsened weakness in 7 of 39 cases who underwent motor mapping (18.0%), numbness in 2 cases (3.2%), agitation in 2 (3.2%), and seizures in 2 (3.2%). Among the patients with new intraoperative deficits, 2 had residual speech difficulty, and 2 had weakness postoperatively, which improved to baseline strength by 6 months.CONCLUSIONSIn this retrospective case series, the combined use of iMRI and awake functional mapping was demonstrated to be safe and feasible. This combined approach allows one to achieve the dual goals of maximal tumor removal and minimal functional consequences in patients undergoing glioma resection.

Utility of repeat magnetic resonance imaging in surgical patients with lumbar stenosis without disc herniation.

BACKGROUND CONTEXT: Routine use of magnetic resonance imaging (MRI) as a diagnostic tool in lumbar stenosis is becoming more prevalent due to the aging population. Currently, there is no clinical guideline to clarify the utility of repeat MRI in patients with lumbar stenosis, without instability, neurological deficits, or disc herniation. PURPOSE: To evaluate the utility of routine use of MRI as a diagnostic tool in lumbar stenosis, and to help formulate clinical guidelines on the appropriate use of preoperative imaging for lumbar stenosis. STUDY DESIGN/SETTING: Retrospective radiographic analysis. PATIENT SAMPLE: Retrospective chart review was performed to review patients with lumbar stenosis, who underwent lumbar decompression without fusion from 2011 to 2015 at a single institution. OUTCOME MEASURES: Previously established stenosis grading systems were used to measure and compare the initial and the subsequent repeat lumbar MRIs performed preoperatively. If patients were found to have a moderate or severe grade change, and if the surgical plan was altered due to such exacerbated radiographic findings, then their grade changes were considered clinically meaningful. METHODS: We identified patients with lumbar stenosis without radiographic instability or neurological deficits, who had at least two preoperative lumbar MRIs performed and underwent decompressive surgeries. At each pathologic disc level, the absolute value of the change in grade for central and lateral recess stenosis, right foraminal stenosis, and left foraminal stenosis from the first preoperative MRI to the repeated MRI was calculated. These changed data were then used to calculate the mean and median changes in each of the three types of stenosis for each pathologic disc level. Identical calculations were carried out for the subsample of patients who only underwent discectomy or had a discectomy included as part of their surgery. RESULTS: Among the 103 patients who met the inclusion criteria, 37 of those patients had more than one level surgically addressed, and a total of 161 lumbar levels were reviewed. Among the subset of patients that had any grade change, the majority of the grades only had a mild change of 1 (36 out of 42 patients, 85.7%, 95% confidence interval [CI]: 73.1%-94.1%); there was a moderate grade change of 2 in two patients (4.8%, CI: 0.8%-14.0%), and a severe change of 3 in one patient (2.4%, CI: 0.2%-10.1%). There were three patients with decreased grade change (7.1%, CI: 1.8%-17.5%). All clinically meaningful grade changes were from the subset of patients who had only discectomy or discectomy as part of the procedure. Lastly, both patients that had a clinically meaningful grade change had their MRIs performed at an interval of greater than 360 days. CONCLUSIONS: The radiographic evaluation of the utility of routinely repeated MRIs in lumbar stenosis without instability, neurological deficits, or disc herniations demonstrated that there were no significant changes found in the repeated MRI in the preoperative setting, especially if the MRIs were performed less than one year apart. The results of this present study can help to standardize the diagnostic evaluation of lumbar stenosis and to formulate clinical guidelines on the appropriate use of preoperative imaging for lumbar stenosis patients.

Intraoperative Multimodal Monitoring in Pedicle Subtraction Osteotomies of the Lumbar Spine: A Narrative Literature Review.

The use of intraoperative multimodal monitoring (IOM) in spinal deformity surgeries is well documented. In particular, pedicle subtraction osteotomy (PSO), a corrective procedure for sagittal deformity of the spine, often involves IOM usage. By providing immediate feedback to the operating surgeon, IOM has the potential to eliminate or at least minimize the risk of iatrogenic neurological injury. However, despite the widespread usage of IOM, there is currently no standardization of IOM usage in complex spine surgeries, including lumbar PSOs, and decisions concerning IOM utilization are often driven by surgeon experience and preference. This creates a state of clinical equipoise, which is further complicated by the varying degrees of benefit that IOM has on patient outcomes depending on the operation and spinal levels involved. For instance, while IOM use in thoracic PSOs has been shown to be effective, there is no established consensus on the net impact of IOM use in PSOs of the lumbar spine. Although IOM has the potential to mitigate neurological damage, it also increases operation time and cost; thus, it should only be used in operations where it will have a net positive impact on patient outcomes. The question thus becomes whether PSO of the lumbar spine is one such operation. To address this, we examine the most frequently used IOM modalities and evaluate their current usage and efficacy in lumbar PSOs. Furthermore, we will also examine the utility of IOM for other surgeries of the lumbar spine, including corrective procedures for idiopathic scoliosis and degenerative scoliosis, and routine lumbar procedures, such as discectomies and decompression surgeries for foraminal and canal stenosis.

Upfront Magnetic Resonance Imaging-Guided Stereotactic Laser-Ablation in Newly Diagnosed Glioblastoma: A Multicenter Review of Survival Outcomes Compared to a Matched Cohort of Biopsy-Only Patients.

BACKGROUND: Laser ablation (LA) is used as an upfront treatment in patients with deep seated newly diagnosed Glioblastoma (nGBM). OBJECTIVE: To evaluate the outcomes of LA in patients with nGBM and compare them with a matched biopsy-only cohort. METHODS: Twenty-four nGBM patients underwent upfront LA at Cleveland clinic, Washington University in St. Louis, and Yale University (6/2011-12/2014) followed by chemo/radiotherapy. Also, 24 out of 171 nGBM patients with biopsy followed by chemo/radiotherapy were matched based on age (< 70 vs ≥ 70), gender, tumor location (deep vs lobar), and volume (<11 cc vs ≥11 cc). Progression-free survival (PFS), overall survival (OS), and disease-specific PFS and OS were outcome measures. Three prognostic groups were identified based on extent of tumor ablation by thermal-damage-threshold (TDT)-lines. RESULTS: The median tumor volume in LA (n = 24) and biopsy only (n = 24) groups was 9.3 cm3 and 8.2 cm3 respectively. Overall, median estimate of OS and PFS in LA cohort was 14.4 and 4.3 mo compared to 15.8 mo and 5.9 mo for biopsy only cohort. On multivariate analysis, favorable TDT-line prognostic groups were associated with lower incidence of disease specific death (P = .03) and progression (P = .05) compared to other groups including biopsy only cohort. Only age (<70 yr, P = .02) and tumor volume (<11 cc, P = .03) were favorable prognostic factors for OS. CONCLUSION: The maximum tumor coverage by LA followed by radiation/chemotherapy is an effective treatment modality in patients with nGBM, compared to biopsy only cohort. The TDT-line prognostic groups were independent predictor of disease specific death and progression after LA.

Assessment of postoperative outcomes in spinal epidural abscess following surgical decompression.

BACKGROUND CONTEXT: A spinal epidural abscess (SEA) is a serious condition that may be managed with antibiotics alone or with decompressive surgery combined with antibiotics. PURPOSE: The objectives of this study were to assess the clinical outcomes of SEA after surgical management and to identify the patient-level factors that are associated with outcomes following surgical decompression and removal of SEA. STUDY DESIGN/SETTING: Retrospective chart review analysis. PATIENT SAMPLE: An analysis of 154 consecutive patients who initially presented to a tertiary-care, academic medical center with SEA, and were subsequently treated with surgery between 2010 and 2015 was performed. OUTCOME MEASURES: Postoperative predischarge American Spinal Injury Association Impairment Scale (AIS) scores, 6-month follow-up encounter AIS scores, need for revision surgery, and mortality during SEA surgery were the primary outcomes.Physiological Measures: AIS scores. METHOD: Fisher's exact and Wilcoxon rank-sum tests were used to assess the associations between patient-level factors and surgical outcomes. Moreover, an interactive, predictive model for postoperative predischarge AIS score was developed using a proportional odds regression model. There was no funding secured for this study and there is no conflict of interest-associated biases. RESULTS: One hundred fifty-four patients (mean age of 58 years) were treated using surgical decompression in addition to antibiotics. The majority of patients were Caucasian (81%) and male (61%). No intraoperative mortality was reported. A second SEA surgery was performed in 8% of patients. A comparison of the preoperative and postoperative predischarge AIS scores showed that 49% of patients maintained a score of E or improved, while 45% remained at their preoperative status and 6% worsened. Among a subset of patients (n=36; 23%) for whom a 6-month follow-up encounter occurred, 75% maintained an AIS score of E or improved, 19% remained at their preoperative status, and 6% worsened. Both the presence and longer duration of preoperative paresis was associated with an increased risk of remaining at the same AIS score or worsening at the predischarge encounter (both p< .001). A predictive model for predischarge AIS scores was developed based on several patient characteristics. CONCLUSIONS: Surgical decompression can contribute to improving or maintaining AIS scores in a high percentage of SEA patients. The presence and duration of preoperative paresis are prognostic for poorer outcomes and suggest that rapid surgical intervention before paresis develops may lead to improved postoperative outcomes. Our modeling tool enables an estimation of probabilities of patients' predischarge condition.

The effect of C2-3 disc angle on postoperative adverse events in cervical spondylotic myelopathy.

OBJECTIVEComplete radiographic and clinical evaluations are essential in the surgical treatment of cervical spondylotic myelopathy (CSM). Prior studies have correlated cervical sagittal imbalance and kyphosis with disability and worse health-related quality of life. However, little is known about C2-3 disc angle and its correlation with postoperative outcomes. The present study is the first to consider C2-3 disc angle as an additional radiographic predictor of postoperative adverse events.METHODSA retrospective chart review was performed to identify patients with CSM who underwent surgeries from 2010 to 2014. Data collected included demographics, baseline presenting factors, and postoperative outcomes. Cervical sagittal alignment variables were measured using the preoperative and postoperative radiographs. Univariable logistic regression analyses were used to explore the association between dependent and independent variables, and a multivariable logistic regression model was created using stepwise variable selection.RESULTSThe authors identified 171 patients who had complete preoperative and postoperative radiographic and outcomes data. The overall rate of postoperative adverse events was 33% (57/171), and postoperative C2-3 disc angle, C2-7 sagittal vertical axis, and C2-7 Cobb angle were found to be significantly associated with adverse events. Inclusion of postoperative C2-3 disc angle in the analysis led to the best prediction of adverse events. The mean postoperative C2-3 disc angle for patients with any postoperative adverse event was 32.3° ± 17.2°, and the mean for those without any adverse event was 22.4° ± 11.1° (p < 0.0001).CONCLUSIONSIn the present retrospective analysis of postoperative adverse events in patients with CSM, the authors found a significant association between C2-3 disc angle and postoperative adverse events. They propose that C2-3 disc angle be used as an additional parameter of cervical spinal sagittal alignment and predictor for operative outcomes.