Single-cell analysis reveals diversity of tumor-associated macrophages and their interactions with T lymphocytes in glioblastoma.

Glioblastoma (GBM) is an aggressive primary CNS malignancy and clinical outcomes have remained stagnant despite introduction of new treatments. Understanding the tumor microenvironment (TME) in which tumor associated macrophages (TAMs) interact with T cells has been of great interest. Although previous studies examining TAMs in GBM have shown that certain TAMs are associated with specific clinical and/or pathologic features, these studies used an outdated M1/M2 paradigm of macrophage polarization and failed to include the continuum of TAM states in GBM. Perhaps most significantly, the interactions of TAMs with T cells have yet to be fully explored. Our study uses single-cell RNA sequencing data from adult IDH-wildtype GBM, with the primary aim of deciphering the cellular interactions of the 7 TAM subtypes with T cells in the GBM TME. Furthermore, the interactions discovered herein are compared to IDH-mutant astrocytoma, allowing for focus on the cellular ecosystem unique to GBM. The resulting ligand-receptor interactions, signaling sources, and global communication patterns discovered provide a framework for future studies to explore methods of leveraging the immune system for treating GBM.

A New Finding on Magnetic Resonance Imaging for Diagnosis of Hemifacial Spasm with High Accuracy and Interobserver Correlation.

Among patients with clinical hemifacial spasm (HFS), imaging exams aim to identify the neurovascular conflict (NVC) location. It has been proven that the identification in the preoperative exam increases the rate of surgical success. Despite the description of specific magnetic resonance image (MRI) acquisitions, the site of neurovascular compression is not always visualized. The authors describe a new MRI finding that helps in the diagnosis of HFS, and evaluate the sensitivity, specificity, and interobserver correlation of the described sign. A cross-sectional study including cases of hemifacial spasm treated surgically from 1 August 2011 to 31 July 2021 was performed. The MRIs of the cases were independently evaluated by two experienced neuroradiologists, who were blinded regarding the side of the symptom. The neuroradiologists were assigned to evaluate the MRIs in two separate moments. Primarily, they evaluated whether there was a neurovascular conflict based on the standard technique. Following this initial analysis, the neuroradiologists received a file with the description of the novel sign, named Prevedello Sign (PS). In a second moment, the same neuroradiologists were asked to identify the presence of the PS and, if it was present, to report on which side. A total of 35 patients were included, mostly females (65.7%) with a mean age of 59.02 (+0.48). Since the 35 cases were independently evaluated by two neuroradiologists, a total of 70 reports were included in the analysis. The PS was present in 66 patients (sensitivity of 94.2%, specificity of 91.4% and positive predictive value of 90.9%). When both analyses were performed in parallel (standard plus PS), the sensitivity increased to 99.2%. Based on the findings of this study, the authors conclude that PS is helpful in determining the neurovascular conflict location in patients with HFS. Its presence, combined with the standard evaluation, increases the sensitivity of the MRI to over 99%, without increasing risks of harm to patients or resulting in additional costs.

A silent corticotroph adenoma: making the case for a pars intermedia origin. Illustrative case.

BACKGROUND: Silent corticotroph adenomas (SCAs) are the only pituitary adenomas thought to originate from the pars intermedia. This case report presents the rare finding of a multimicrocystic corticotroph macroadenoma displacing the anterior and posterior lobes of the pituitary gland on magnetic resonance imaging (MRI). This finding supports the hypothesis that silent corticotroph adenomas may originate from the pars intermedia and should be considered in the differential for tumors arising from this location. OBSERVATIONS: A 55-year-old man presented with an episode of confusion and blurred vision. MRI demonstrated separation of the anterior and posterior glands by a solid-cystic lesion located within the pars intermedia that superiorly displaced the optic chiasm. Endocrinologic evaluation was unremarkable. The differential diagnosis included pituitary adenoma, Rathke cleft cyst, and craniopharyngioma. The tumor was confirmed to be an SCA on pathology and was completely removed through the endoscopic endonasal transsphenoidal approach. LESSONS: The case highlights the importance of preoperative screening for subclinical hypercortisolism for tumors arising from this location. Knowledge of a patient's preoperative functional status is critical and dictates their postoperative biochemical assessment to determine remission. The case also illustrates surgical strategies for resecting pars intermedia lesions without injuring the gland.

Spontaneous rhinorrhea: a possible concealing initial symptom of ecchordosis physaliphora. Illustrative case.

BACKGROUND: Spontaneous rhinorrhea may be the initial manifestation of ecchordosis physaliphora (EP). There are currently 47 published cases of symptomatic EP, with spontaneous rhinorrhea being one of the most prevalent symptoms. The authors report 1 case as a cause of cerebrospinal fluid (CSF) fistula. OBSERVATIONS: A 46-year-old woman presented to the authors' clinic with meningitis secondary to nasal CSF leakage. The computed tomography (CT) scan indicated an imperceptibly thin/dehiscent focus along the posterior wall of the sphenoid air cell's midline. A tumor was identified during endoscopic endonasal CSF repair surgery. EP was diagnosed in the frozen and final pathology. LESSONS: EP should be considered as a potential cause of spontaneous rhinorrhea. This initial clinical manifestation accounts for 35% of symptomatic EP cases. The prepontine and posterior sphenoid sinus wall appear to be the locations with the highest susceptibility. Surgical therapy of the fistula without excision of the lesion may result in insufficient issue resolution and recurrence.

Long-term tumor control after endoscopic endonasal resection of craniopharyngiomas: comparison of gross-total resection versus subtotal resection with radiation therapy.

OBJECTIVE: Surgical management of craniopharyngiomas (CPAs) is challenging. Controversy exists regarding the optimal goals of surgery. The purpose of this study was to compare the long-term outcomes of patients who underwent gross-total resection with the outcomes of those who underwent subtotal resection of their CPA via an endoscopic endonasal approach. METHODS: From a prospectively maintained database of all endoscopic endonasal approaches performed at Weill Cornell Medicine, only patients with CPAs with > 3 years of follow-up after surgery were included. The primary endpoint was radiographic progression. Data were collected on baseline demographics, imaging, endocrine function, visual function, and extent of resection. RESULTS: A total of 44 patients with a mean follow-up of 5.7 ± 2.6 years were included. Of these patients, 14 (31.8%) had prior surgery. GTR was achieved in 77.3% (34/44) of all patients and 89.5% (34/38) of patients in whom it was the goal of surgery. Preoperative tumor volume < 10 cm3 was highly predictive of GTR (p < 0.001). Radiation therapy was administered within the first 3 months after surgery in 1 (2.9%) of 34 patients with GTR and 7 (70%) of 10 patients with STR (p < 0.001). The 5-year recurrence-free/progression-free survival rate was 75.0% after GTR and 25.0% after STR (45% in subgroup with STR plus radiotherapy; p < 0.001). The time to recurrence after GTR was 30.2 months versus 13 months after STR (5.8 months in subgroup with STR plus radiotherapy; p < 0.001). Patients with GTR had a lower rate of visual deterioration and higher rate of return to work or school compared with those with STR (p = 0.02). Patients with GTR compared to STR had a lower rate of CSF leakage (0.0% vs 30%, p = 0.001) but a higher rate of diabetes insipidus (85.3% vs 50%, p = 0.02). CONCLUSIONS: GTR, which is possible to achieve in smaller tumors, resulted in improved tumor control, better visual outcome, and better functional recovery but a higher rate of diabetes insipidus compared with STR, even when the latter was supplemented with postoperative radiation therapy. GTR should be the goal of craniopharyngioma surgery, when achievable with minimal morbidity.

Defining the relative utility of lumbar spine surgery: A systematic literature review of common surgical procedures and their impact on health states.

Degenerative lumbar spondylosis is a common indication for patients undergoing spine surgery. As healthcare costs rise, measuring quality of life (QOL) gains after surgical procedures is critical in assessing value. We set out to: 1) compare baseline and postoperative EuroQol-5D (EQ-5D) scores for lumbar spine surgery and common surgical procedures to obtain post-operative quality-adjusted life year (QALY) gain, and 2) establish the relative utility of lumbar spine surgery as compared to other commonly performed surgical procedures. A systematic literature review was conducted to identify all studies reporting preoperative/baseline and postoperative EQ-5D scores for common surgical procedures. For each study, the number of patients included and baseline/preoperative and follow-up mean EQ-5D scores were recorded, and mean QALY gained for each intervention was calculated. A total of 67 studies comprising 95,014 patients were identified. Patients with lumbar spondylosis had the worst reported QOL at baseline compared to other surgical cohorts. The greatest QALY gain was seen in patients undergoing hip arthroplasty (0.38), knee arthroplasty (0.35) and lumbar spine surgery (0.32), nearly 2.5-fold greater QALY gained than for all other procedures. The low preoperative QOL, coupled with the improvements offered with surgery, highlight the utility and value of lumbar spine surgery compared to other common surgical procedures.

Bone Cement Cranioplasty Reduces Cerebrospinal Fluid Leak Rate after Microvascular Decompression: A Single-Institutional Experience.

Background Microvascular decompression (MVD) is a common surgical treatment for cranial nerve compression, though cerebrospinal fluid (CSF) leak is a known complication of this procedure. Bone cement cranioplasty may reduce rates of CSF leak. Objective To compare rates of CSF leak before and after implementation of bone cement cranioplasty for the reconstruction of cranial defects after MVD. Methods Retrospective chart review was performed of patients who underwent MVD through retrosigmoid craniectomy for cranial nerve compression at a single institution from 1998 to 2017. Study variables included patient demographics, medical history, type of closure, and postoperative complications such as CSF leak, meningitis, lumbar drain placement, and ventriculoperitoneal shunt insertion. Cement and noncement closure groups were compared, and predictors of CSF leak were assessed using a multivariate logistic regression model. Results A total of 547 patients treated by 10 neurosurgeons were followed up for more than 20 years, of whom 288 (52.7%) received cement cranioplasty and 259 (47.3%) did not. Baseline comorbidities were not significantly different between groups. CSF leak rate was significantly lower in the cement group than in the noncement group (4.5 vs. 14.3%; p < 0.001). This was associated with significantly fewer patients developing postoperative meningitis (0.7 vs. 5.2%; p = 0.003). Multiple logistic regression model demonstrated noncement closure as the only independent predictor of CSF leak (odds ratio: 3.55; 95% CI: 1.78-7.06; p < 0.001). Conclusion CSF leak is a well-known complication after MVD. Bone cement cranioplasty significantly reduces the incidence of postoperative CSF leak and other complications. Modifiable risk factors such as body mass index were not associated with the development of CSF leak.

Long-term outcomes after endoscopic endonasal surgery for nonfunctioning pituitary macroadenomas.

OBJECTIVE: Nonfunctioning pituitary adenomas are benign, slow-growing tumors. After gross-total resection (GTR) or subtotal resection (STR), tumors can recur or progress and may ultimately require additional intervention. A greater understanding of long-term recurrence and progression rates following complete or partial resection and the need for further intervention will help clinicians provide meaningful counsel for their patients and assist data-driven decision-making. METHODS: The authors retrospectively analyzed their institutional database for patients undergoing endoscopic endonasal surgery (EES) for nonfunctioning pituitary macroadenomas (2003-2014). Only patients with follow-up of at least 5 years after surgery were included. Tumor volumes were measured on pre- and postoperative MRI. Tumor recurrence was defined as the presence of a 0.1-cm3 tumor volume after GTR, and tumor progression was defined as a 25.0% increase in residual tumor after STR. RESULTS: A total of 190 patients were included, with a mean age of 63.8 ± 13.2 years; 79 (41.6%) were female. The mean follow-up was 75.0 ± 18.0 months. GTR was achieved in 127 (66.8%) patients. In multivariate analysis, age (p = 0.04), preoperative tumor volume (p = 0.03), Knosp score (p < 0.001), and Ki-67 (p = 0.03) were significant predictors of STR. In patients with GTR, the probability of recurrence at 5 and 10 years was 3.9% and 4.7%, and the probability of requiring treatment for recurrence was 0.79% and 1.6%, respectively. In 63 patients who underwent STR, 6 (9.5%) received early postoperative radiation and did not experience progression, while the remaining 57 (90.5%) were observed. Of these, the probability of disease progression at 5 and 10 years was 21% and 24.5%, respectively, and the probability of requiring additional treatment for progression was 17.5% and 21%. Predictors of recurrence or progression in the entire group were Knosp score (p < 0.001) and elevated Ki-67 (p = 0.03). Significant predictors of progression after STR in those who did not receive early radiotherapy were cavernous sinus location (p < 0.05) and tumor size > 1.0 cm3 (p = 0.005). CONCLUSIONS: Following GTR for nonfunctioning pituitary adenomas, the 10-year chance of recurrence is low and the need for treatment even lower. After STR, although upfront radiation therapy may prevent progression, even without radiotherapy, the need for intervention at 10 years is only approximately 20% and a period of observation may be warranted to prevent unnecessary prophylactic radiation therapy. Tumor volume > 1 cm3, Knosp score ≥ 3, and Ki-67 ≥ 3% may be useful metrics to prompt closer follow-up or justify early prophylactic radiation therapy.

Endoscopic Endonasal Transclival Resection of a Pontine Metastasis: Case Report and Operative Video.

BACKGROUND AND IMPORTANCE: Brainstem lesions are challenging to manage, and surgical options have been controversial. Stereotactic radiosurgery (SRS) has been used for local control, but life-threatening toxicities from 0% to 9.5% have been reported. Several microsurgical approaches involving safe entry zones have been developed to optimize the exposure and minimize complications in different portions of the brainstem, but require extensive drilling and manipulation of neurovascular structures. With recent advancements, the endoscopic endonasal approach (EEA) can provide direct visualization of ventral brainstem. No case has been reported of EEA to remove a brainstem metastasis. CLINICAL PRESENTATION: We present an illustrative case of a 68-yr-old female with metastatic colon cancer who presented with 2.8 × 2.7 × 2.1 cm (7.9 cm3) heterogeneously enhancing, right ventral pontine lesion with extensive edema. She underwent endoscopic endonasal transclival approach, and gross total resection of the lesion was achieved. CONCLUSION: The endoscopic approach may offer certain advantages for removal of ventral brainstem lesions, as it can provide direct visualization of important neurovascular structures, especially, if the lesion displaces the tracts and comes superficial to the pial surface.

Endoscopic transorbital approach to the infratemporal fossa and parapharyngeal space: a cadaveric study.

OBJECTIVE: The infratemporal fossa (ITF) and parapharyngeal space are anatomical regions that can be challenging to access without the use of complex, cosmetically disfiguring approaches. With advances in endoscopic techniques, a new group of surgical approaches to access the intracranial space through the orbit has been recently referred to as transorbital neuroendoscopic surgery (TONES). The objective of this study was to establish a transorbital endoscopic approach utilizing the inferior orbital fissure (IOF) to gain access to the ITF and parapharyngeal space and provide a detailed endoscopic anatomical description of this approach. METHODS: Four cadaveric heads (8 sides) were dissected using a TONES approach through the IOF to reach the ITF and parapharyngeal space, providing stepwise dissection with detailed anatomical findings and a description of each step. RESULTS: An inferior eyelid approach was made with subperiosteal periorbital dissection to the IOF. The zygomatic and greater wing of the sphenoid were drilled, forming the boundaries of the IOF. The upper head of the lateral pterygoid muscle in the ITF and parapharyngeal space was removed, and 7 distinct planes were described, each with its own anatomical contents. The second part of the maxillary artery was mainly found in plane 1 between the temporalis laterally and the lateral pterygoid muscle in plane 2. The branches of the mandibular nerve (V3) and middle meningeal artery (MMA) were identified in plane 3. Plane 4 was formed by the fascia of the medial pterygoid muscle (MTM) and the tensor veli palatini muscle. The prestyloid segment, found in plane 5, was composed mainly of fat and lymph nodes. The parapharyngeal carotid artery in the poststyloid segment, found in plane 7, was identified after laterally dissecting the styloid diaphragm, found in plane 6. V3 and the origin of the levator and tensor veli palatini muscles serve as landmarks for identification of the parapharyngeal carotid artery. CONCLUSIONS: The transorbital endoscopic approach provides excellent access to the ITF and parapharyngeal space compared to previously described complex and morbid transfacial or transcranial approaches. Using the IOF is an important and useful landmark that permits a wide exposure.

Incidence and risk factors associated with reoperation for sellar hematoma following endoscopic transsphenoidal pituitary surgery.

OBJECTIVE: Postoperative sellar hematoma is an uncommon complication of endonasal endoscopic transsphenoidal surgery (EETS) for pituitary adenoma that often requires emergency surgical evacuation. Sellar hematomas can cause mass effect and compress parasellar structures, leading to clinically significant symptoms such as visual impairment and severe headache. The objective of this study was to determine the incidence and risk factors associated with reoperation for postoperative hematoma after EETS for pituitary adenoma. METHODS: The authors reviewed a prospectively acquired database of EETS for pituitary adenoma over 13 years at Weill Cornell Medicine, NewYork-Presbyterian Hospital and identified cases that required reoperation for confirmed hematoma. They also reviewed clinical and radiographic data of a consecutive series of patients undergoing EETS for pituitary adenoma who did not have postoperative hematoma, which served as the control group. Demographic data and risk factors were compared between the groups using univariate and multivariate analyses via binary logistic regression. RESULTS: Among a cohort of 583 patients undergoing EETS for pituitary adenoma, 9 patients (1.5%) required operation for sellar hematoma evacuation. All 9 patients with reoperation for sellar hematoma presented with worsening in their vision, and severe headache was present in 67%. New postoperative endocrine dysfunction developed in 78%. Clot evacuation improved vision in 88%. The mean time to hematoma evacuation was 4.5 days. The median length of stay for patients with sellar hematoma was 8 days (range 4-210 days) compared with a median length of stay of 3 days (range 1-32 days) for the control patients (p < 0.005). Significant risk factors in univariate analysis were tumor diameter ≥ 30 mm (p < 0.005), suprasellar extension (p < 0.005), tumor volume (p < 0.005), cavernous sinus invasion (p < 0.05), gonadotroph histology (p < 0.05), antiplatelet use (p < 0.05), and elevated BMI (p < 0.05). On multivariate analysis, tumor diameter ≥ 30 mm (OR 4.555, CI 1.30-28.90; p < 0.05) and suprasellar extension (OR 1.048, CI 1.01-1.10; p < 0.05) were found to be the only independent predictors of sellar hematoma. The incidence of hematoma in tumors ≥ 30 mm was 5% (7/139). CONCLUSIONS: Postoperative sellar hematoma requiring reoperation is a rare phenomenon after transsphenoidal surgery, often presenting with visual loss and headache. Clot evacuation results in improvement in vision, but long-term endocrinopathy often ensues. Tumor diameter ≥ 30 mm and suprasellar extent are the most reliable risk factors. Close postoperative scrutiny should be given to patients at high risk.

Genomic profile of a primary squamous cell carcinoma arising from malignant transformation of a pineal epidermoid cyst.

Malignant transformation of intracranial epidermoid cysts is a rare occurrence. We present the second case of such an event occurring in the pineal region and the first case sent for detailed genomic profiling. MRI demonstrated two lesions: a cyst in a quadrigeminal cistern with restricted diffusion on DWI-weighted images and an adjacent, peripherally enhancing tumor with cerebellar infiltration. Both the lesions were completely resected with a small residual of the epidermoid cyst. The final pathology of both lesions was consistent with epidermoid cyst and squamous cell carcinoma (SCC), respectively. The tumor specimen was sent for comprehensive genomic profiling which revealed stable microsatellite status and loss of CDKN2A/B, MTAP (exons 2-8), and PTEN (exons 6-9). Although reports of primary SCC originating from the epidermoid cyst have been previously described, this is the first description of the genomic profile of such a tumor.

Anterior cervical discectomy and fusion in the outpatient ambulatory surgery setting compared with the inpatient hospital setting: analysis of 1000 consecutive cases.

OBJECTIVE In an era of escalating health care costs and pressure to improve efficiency and cost of care, ambulatory surgery centers (ASCs) have emerged as lower-cost options for many surgical therapies. Anterior cervical discectomy and fusion (ACDF) is one of the most prevalent spine surgeries performed, and the frequency of its performance is rapidly increasing as the aging population grows. Although ASCs offer significant cost advantages over hospital-based surgical centers, concern over the safety of outpatient ACDF has slowed its adoption. The authors intended to 1) determine the safety of the first 1000 consecutive ACDF surgeries performed in their outpatient ASC, and 2) compare the safety of these outpatient ACDFs with that of consecutive ACDFs performed during the same time period in the hospital setting. METHODS A total of 1000 consecutive patients who underwent ACDF in an ACS (outpatient ACDF) and 484 consecutive patients who underwent ACDF at Vanderbilt University Hospital (inpatient ACDF) from 2006 to 2013 were included in this retrospective study of patients' medical records. Data were collected on patient demographics, comorbidities, operative details, and perioperative and 90-day morbidity. Perioperative morbidity and hospital readmission were compared between the outpatient and inpatient ACDF groups. RESULTS Of the first 1000 outpatient ACDF cases performed in the authors' ASC, 629 (62.9%) were 1-level and 365 (36.5%) were 2-level ACDFs. Mean patient age was 49.5 ± 8.6, and 484 (48.4%) were males. All patients were observed postoperatively at the ASC postanesthesia care unit (PACU) for 4 hours before being discharged home. Eight patients (0.8%) were transferred from the surgery center to the hospital postoperatively (for pain control [n = 3], chest pain and electrocardiogram changes [n = 2], intraoperative CSF leak [n = 1], postoperative hematoma [n = 1], and profound postoperative weakness and surgical reexploration [n = 1]). No perioperative deaths occurred. The 30-day hospital readmission rate was 2.2%. All 90-day surgical morbidity was similar between outpatient and inpatient cohorts for both 1-level and 2-level ACDFs. CONCLUSIONS An analysis of 1000 consecutive patients who underwent ACDF in an outpatient setting demonstrates that surgical complications occur at a low rate (1%) and can be appropriately diagnosed and managed in a 4-hour ASC PACU window. Comparison with an inpatient ACDF surgery cohort demonstrated similar results, highlighting that ACDF can be safely performed in the outpatient ambulatory surgery setting without compromising surgical safety. In an effort to decrease costs of care, surgeons can safely perform 1- and 2-level ACDFs in an ASC environment.

Patient-reported outcomes 3 months after spine surgery: is it an accurate predictor of 12-month outcome in real-world registry platforms?

OBJECT The health care landscape is rapidly shifting to incentivize quality of care rather than quantity of care. Quality and outcomes registry platforms lie at the center of all emerging evidence-driven reform models and will be used to inform decision makers in health care delivery. Obtaining real-world registry outcomes data from patients 12 months after spine surgery remains a challenge. The authors set out to determine whether 3-month patient-reported outcomes accurately predict 12-month outcomes and, hence, whether 3-month measurement systems suffice to identify effective versus noneffective spine care. METHODS All patients undergoing lumbar spine surgery for degenerative disease at a single medical institution over a 2-year period were enrolled in a prospective longitudinal registry. Patient-reported outcome instruments (numeric rating scale [NRS], Oswestry Disability Index [ODI], 12-Item Short Form Health Survey [SF-12], EQ-5D, and the Zung Self-Rating Depression Scale) were recorded prospectively at baseline and at 3 months and 12 months after surgery. Linear regression was performed to determine the independent association of 3- and 12-month outcome. Receiver operating characteristic (ROC) curve analysis was performed to determine whether improvement in general health state (EQ-5D) and disability (ODI) at 3 months accurately predicted improvement and achievement of minimum clinical important difference (MCID) at 12 months. RESULTS A total of 593 patients undergoing elective lumbar surgery were included in the study. There was a significant correlation between 3-month and 12-month EQ-5D (r = 0.71; p < 0.0001) and ODI (r = 0.70; p < 0.0001); however, the authors observed a sizable discrepancy in achievement of a clinically significant improvement (MCID) threshold at 3 versus 12 months on an individual patient level. For postoperative disability (ODI), 11.5% of patients who achieved an MCID threshold at 3 months dropped below this threshold at 12 months; 10.5% of patients who did not meet the MCID threshold at 3 months continued to improve and ultimately surpassed the MCID threshold at 12 months. For ODI, achieving MCID at 3 months accurately predicted 12-month MCID with only 62.6% specificity and 86.8% sensitivity. For postoperative health utility (EQ-5D), 8.5% of patients lost an MCID threshold improvement from 3 months to 12 months, while 4.0% gained the MCID threshold between 3 and 12 months postoperatively. For EQ-5D (quality-adjusted life years), achieving MCID at 3 months accurately predicted 12-month MCID with only 87.7% specificity and 87.2% sensitivity. CONCLUSIONS In a prospective registry, patient-reported measures of treatment effectiveness obtained at 3 months correlated with 12-month measures overall in aggregate, but did not reliably predict 12-month outcome at the patient level. Many patients who do not benefit from surgery by 3 months do so by 12 months, and, conversely, many patients reporting meaningful improvement by 3 months report loss of benefit at 12 months. Prospective longitudinal spine outcomes registries need to span at least 12 months to identify effective versus noneffective patient care.

Quality analysis of anterior cervical discectomy and fusion in the outpatient versus inpatient setting: analysis of 7288 patients from the NSQIP database.

OBJECT In an era of escalating health care cost and universal pressure of improving efficiency and cost of care, ambulatory surgery centers (ASCs) have emerged as lower cost options for many surgical therapies. Anterior cervical discectomy and fusion (ACDF) is one of the most prevalent spine surgeries performed and is rapidly increasing with an expanding aging population. While ASCs offer cost advantages for ACDF, there is a scarcity of evidence that ASCs allow for equivalent quality and thus superior health care value. Therefore, the authors analyzed a nationwide, prospective quality improvement registry (National Surgical Quality Improvement Program [NSQIP]) to compare the quality of ACDF surgery performed in the outpatient ASC versus the inpatient hospital setting. METHODS Patients undergoing ACDF (2005-2011) were identified from the NSQIP database based on the primary Current Procedural Terminology codes. Patients were divided into 2 cohorts (outpatient vs inpatient) based on the acute care setting documented in the NSQIP database. All 30-day surgical morbidity and mortality rates were compared between the 2 groups. Propensity score matching and multivariate logistic regression analysis were used to adjust for confounding factors and to identify the independent association of outpatient ACDF with perioperative outcomes and morbidity. RESULTS A total of 7288 ACDF cases were identified (inpatient = 6120, outpatient = 1168). Unadjusted rates of major morbidity (0.94% vs 4.5%, p < 0.001) and return to the operating room (OR) within 30 days (0.3% vs 2.0%, p < 0.001) were significantly lower in outpatient versus inpatient ACDF. After propensity matching 1442 cases (inpatient = 650, outpatient = 792) based on baseline 32 covariates, rates of major morbidity (1.4% vs 3.1%, p = 0.03), and return to the OR (0.34% vs 1.4%, p = 0.04) remained significantly lower after outpatient ACDF. Adjusted comparison using multivariate logistic regression demonstrated that ACDF performed in the outpatient setting had 58% lower odds of having a major morbidity and 80% lower odds of return to the OR within 30 days. CONCLUSIONS An analysis of a nationwide, prospective quality improvement registry representing more than 250 hospitals demonstrates that 1- to 2-level ACDF can be safely performed in the outpatient ambulatory surgery setting in patients who are appropriate candidates. In an effort to decrease cost of care, surgeons can safely consider performing ACDF in an ASC environment.

Do Patient Demographics and Patient-Reported Outcomes Predict 12-Month Loss to Follow-Up After Spine Surgery?

STUDY DESIGN: Analysis of patients in a prospective registry. OBJECTIVE: To determine the association between patient demographics, outcomes, and loss to follow-up 12 months after spine surgery. SUMMARY OF BACKGROUND DATA: Obtaining outcomes 12 months after spine surgery remains a challenge. Loss to follow-up is believed to introduce biases and portend poor outcomes. Associations between follow-up, patient demographics, and outcomes in the degenerative spine population have not been studied. METHODS: Patients undergoing surgery for degenerative spine disease at a single institution over a 2-year period were enrolled in a prospective registry. Patient demographics, comorbidities, treatment variables, readmissions/reoperations, and all 90-day surgical morbidity were collected. Patient-reported outcomes were recorded at baseline, 3-months, and 12-months after surgery. Multivariate logistic regression analysis was done to identify predictors of loss to follow-up. RESULTS: A total of 1484 patients with baseline and 3-month outcomes were included. Two hundred thirty-three (15.7%) patients were lost to follow-up at 12 months. There was no difference in the baseline demographics (Sex: P = 0.46) and comorbidities (American Society of Anesthesiologists Grade: P = 0.06) of patients who had follow-up at 12-months versus those who did not, except age and employment status. Patients lost to follow-up at 12 months were younger (51.0 vs. 57.1 years; P < 0.001) and a higher proportion were employed preoperatively (45.9% vs. 41.7%, P = 0.24). Preoperative pain, disability, and quality of life was similar between the two groups (P > 0.05). There was no difference in 90-day morbidity (17.2% vs. 16.2%; P = 0.70) and 3-month pain, disability, quality of life, and patient satisfaction (85.0% vs. 88.3%; P = 0.63) (P > 0.05). In multivariate model, only younger age (P < 0.001) was an independent predictor of loss to follow-up at 12 months. CONCLUSION: In our prospective spine registry the 12-month loss to follow-up rate is approximately 15%. The only independent predictor of loss to follow-up is younger age and preoperative employment. LEVEL OF EVIDENCE: 3.

Quality of Life and General Health After Elective Surgery for Cervical Spine Pathologies: Determining a Valid and Responsive Metric of Health State Utility.

BACKGROUND: As part of the Affordable Care Act, health utility metrics are being investigated to define a cost-effective, value-based health care model. EuroQOL-5D (EQ-5D) and Short Form-6D (SF-6D) are commonly used quality-of-life instruments. Domains in the EQ-5D questionnaire are thought to be less responsive in measuring quality of life after cervical surgery. OBJECTIVE: To evaluate the validity and responsiveness of SF-6D and EQ-5D in determining health and quality of life after elective cervical spine surgery. METHODS: A total of 420 patients undergoing elective cervical spine surgery over a period of 2 years were enrolled in a prospective longitudinal registry. Patient-reported outcomes Neck Disability Index (NDI), EQ-5D, and SF-12 were recorded. Based on previously published equations, SF-6D was calculated using NDI and SF-12 scores. Patients were asked whether "surgery met their expectations" (meaningful improvement). The validity and relative responsiveness of SF-6D (NDI), SF-6D (SF-12), and EQ-5D to discriminate between meaningful and nonmeaningful improvement were calculated. RESULTS: Sixty-six percent of patients (277) reported a level of improvement after surgery that met their expectations (meaningful improvement). SF-6D (NDI) (area under the curve [AUC] = 0.69) was a more valid discriminator of meaningful improvement compared with the SF-6D (SF-12) (AUC = 0.65) and EQ-5D (AUC = 0.62). SF-6D (NDI) was also a more responsive measure compared with SF-6D (SF-12) and EQ-5D (standardized response mean difference: 0.66, 0.48, and 0.44, respectively). CONCLUSION: SF-6D is a more valid and responsive measure of general health and quality of life compared with EQ-5D. SF-6D derived from disease-specific disability scores was more valid and responsive than that derived from the generic preference-based SF-12. Cost-effective studies should use SF-6D as a measure of QALY after cervical spine surgery.

Incidence of Low Back Pain After Lumbar Discectomy for Herniated Disc and Its Effect on Patient-reported Outcomes.

BACKGROUND: Long-term postdiscectomy degenerative disc disease and low back pain is a well-recognized disorder; however, its patient-centered characterization and quantification are lacking. QUESTIONS/PURPOSES: We performed a systematic literature review and prospective longitudinal study to determine the frequency of recurrent back pain after discectomy and quantify its effect on patient-reported outcomes (PROs). METHODS: A MEDLINE search was performed to identify studies reporting on the frequency of recurrent back pain, same-level recurrent disc herniation, and reoperation after primary lumbar discectomy. After excluding studies that did not report the percentage of patients with persistent back or leg pain more than 6 months after discectomy or did not report the rate of same level recurrent herniation, 90 studies, which in aggregate had evaluated 21,180 patients, were included in the systematic review portion of this study. For the longitudinal study, all patients undergoing primary lumbar discectomy between October 2010 and March 2013 were enrolled into our prospective spine registry. One hundred fifteen patients were more than 12 months out from surgery, 103 (90%) of whom were available for 1-year outcomes assessment. PROs were prospectively assessed at baseline, 3 months, 1 year, and 2 years. The threshold of deterioration used to classify recurrent back pain was the minimum clinically important difference in back pain (Numeric Rating Scale Back Pain [NRS-BP]) or Disability (Oswestry Disability Index [ODI]), which were 2.5 of 10 points and 20 of 100 points, respectively. RESULTS SYSTEMATIC REVIEW: The proportion of patients reporting short-term (6-24 months) and long-term (> 24 months) recurrent back pain ranged from 3% to 34% and 5% to 36%, respectively. The 2-year incidence of recurrent disc herniation ranged from 0% to 23% and the frequency of reoperation ranged from 0% to 13%. PROSPECTIVE STUDY: At 1-year and 2-year followup, 22% and 26% patients reported worsening of low back pain (NRS: 5.3 ± 2.5 versus 2.7 ± 2.8, p < 0.001) or disability (ODI%: 32 ± 18 versus 21 ± 18, p < 0.001) compared with 3 months. CONCLUSIONS: In a systematic literature review and prospective outcomes study, the frequency of same-level disc herniation requiring reoperation was 6%. Two-year recurrent low back pain may occur in 15% to 25% of patients depending on the level of recurrent pain considered clinically important, and this leads to worse PROs at 1 and 2 years postoperatively.

Transforaminal lumbar interbody graft placement using an articulating delivery arm facilitates increased segmental lordosis with superior anterior and midline graft placement.

OBJECTIVE: Transforaminal lumbar interbody fusion (TLIF) is a frequently performed method of lumbar arthrodesis in patients failing medical management of back and leg pain. Accurate placement of the interbody graft and restoration of lordosis has been shown to be crucial when performing lumbar fusion procedures. We performed a single-surgeon, prospective, randomized study to determine whether a novel articulating versus traditional straight graft delivery arm system allows for superior graft placement and increased lordosis for single-level TLIF. METHODS: Thirty consecutive patients undergoing single-level TLIF were included and prospectively randomized to one of the 2 groups (articulated vs. straight delivery arm system). Three radiographic characteristics were evaluated at 6-week follow-up: (1) degree of segmental lumbar lordosis at the fused level; (2) the percent anterior location of the interbody graft in disk space; and (3) the distance (mm) off midline of the interbody graft placement. RESULTS: Randomization yielded 16 patients in the articulated delivery arm cohort and 14 in the straight delivery arm cohort. The articulating delivery arm system yielded an average of 14.7-degree segmental lordosis at fused level, 35% anterior location, and 3.6 mm off midline. The straight delivery arm system yielded an average of 10.7-degree segmental lordosis at fused level, 46% anterior location, and 7.0 mm off midline. All 3 comparisons were statistically significant (P<0.05). CONCLUSIONS: The study suggests that an articulating delivery arm system facilitates superior anterior and midline TLIF graft placement allowing for increased segmental lordosis compared with a traditional straight delivery arm system.