Factors associated with hardware failure after lateral thoracolumbar fusions - A ten year case series.

OBJECTIVE: Thoracolumbar lateral interbody fusions (tLLIF) are one tool in the spine surgeon's toolbox to indirectly decompress neuroforamina while also improving segmental lordosis in a biomechanically distinct manner from posterior fusions. When part of a concomitant posterior construct, hardware failure (HF), sometimes requiring revision surgery, can occur. We sought to study the relationship between tLLIF and HF. METHODS: We conducted a retrospective study on consecutive patents who underwent tLLIF at a single academic center between January 2012 and December 2021 by seven unique neurosurgeons. Patients were excluded if they had no posterior instrumentation within their construct or if they had less than six months of follow-up. Hardware failure was defined as screw breakage or rod fracture seen on postoperative imaging. RESULTS: 232 patients were identified; 6 (2.6 %) developed HF throughout a mean follow-up of 1182 days (range =748-1647 days). Adjacent segment disease was the most common pathology addressed (75 patients (32.3 %)). The amount of posterior instrumentation both in the surgery in question and in the total construct were significantly higher in the HF cohort (4.33 ± 1.52 levels, 5.83 ± 3.36 levels) versus the non-HF cohort (2.08 ± 0.296 levels, p = 0.014; 2.86 ± 0.316 levels, p = 0.003, respectively). The number of interbody devices added in the index surgery and in the entire construct were both significantly higher in the HF cohort (3.33 ± 0.666 interbody devices, 3.33 ± 0.666 devices) than in the non-HF cohort (1.88 ± 0.152 interbody devices, p = 0.002; 2.31 ± 0.158 devices, p = 0.036, respectively). Higher amounts of lateral levels of fusion approached significance for association with HF (HF: 2.67 ± 0.844 levels, no HF: 1.73 ± 1.26 levels, p = 0.076). On multivariate analysis, only the number of interbody devices added in the index surgery was predictive of HF (Odds ratio=2.3, 95 % confidence interval=1.25-4.23, p = 0.007). CONCLUSION: Greater levels of posterior fusion, and greater numbers of interbody devices in an index surgery and in a construct as a whole, were associated with higher rates of HF in our cohort of patients with tLLIF. Greater numbers of lateral segments fused in this population may also be related to HF.

Paramedian Wiltse Approach for Giant Paraspinal Lumbar Schwannoma: Technical Note and Alternative Approaches.

BACKGROUND: Paraspinal lumbar schwannomas are primarily located outside of the spinal canal with minimal extension into the neural foramen. Approaching these tumors through a traditional posterior approach can be challenging given their lateral location to the spine and is likely to require extensive bony removal and potential destabilization of the spine. Alternatives approaches have been identified that may circumvent the need for extensive bony removal. OBJECTIVE: To examine the use of the paramedian Wiltse approach for giant extraspinal tumors and compare the approach with other nonposterior approaches. METHODS: We present 2 cases in which the paramedian Wiltse approach is used to effectively approach large paraspinal schwannomas and achieve complete tumor resection without destabilization of the spine. RESULTS: The paramedian Wiltse approach along with expandable retractors systems were able to achieve complete resection of the giant paraspinal schwannomas. Neural preservation was able to be achieved in one case which was facilitated by the exposure achieved through the posterior paramedian corridor that allowed for visualization of the proximal and distal ends of the tumor. CONCLUSION: The paramedian Wiltse approach is an ideal approach to target large extraspinal schwannomas for complete resection and potential neural preservation without the need for destabilization of the spine.

Surgical and anatomic factors predict development of leptomeningeal disease in patients with melanoma brain metastases.

BACKGROUND: Leptomeningeal disease (LMD) is a devastating complication of systemic malignancy, of which there is an unclear etiology. The aim of this study is to determine if surgical or anatomic factors can predict LMD in patients with metastatic melanoma. METHODS: A retrospective chart review was performed of 1162 patients treated at single institution for melanoma brain metastases (MBM). Patients with fewer than 3 months follow-up or lacking appropriate imaging were excluded. Demographic information, surgical, and anatomic data were collected. RESULTS: Eight hundred and twenty-seven patients were included in the final review. On multivariate analysis for the entire cohort, female gender, dural-based and intraventricular metastasis, and tumor bordering CSF spaces were associated with increased risk of LMD. Surgical resection was not significant for risk of LMD. On multivariate analysis of patients who have undergone surgical resection of a metastatic tumor, dural-based and intraventricular metastasis, ventricular entry during surgery, and metastasis in the infratentorial space were associated with increased risk of LMD. On multivariate analysis of patients who did not undergo surgery, chemotherapy after initial diagnosis and metastasis bordering CSF spaces were associated with increased risk of LMD. CONCLUSION: In a single-institution cohort of MBM, we found that surgical resection alone did not result in an increased risk of LMD. Anatomical factors such as dural-based and intraventricular metastasis were significant for developing LMD, as well as entry into a CSF space during surgical resection. These data suggest a strong correlation between anatomic location and tumor cell seeding in relation to the development of LMD.

Safety comparison of minimally invasive abdomen-only esophagectomy versus minimally invasive Ivor Lewis esophagectomy: a retrospective cohort study.

BACKGROUND: We report mortality and post-operative complications from esophageal resection in the treatment of gastroesophageal adenocarcinoma or stricture, comparing a minimally invasive abdomen-only esophagectomy (MIAE) approach with a minimally invasive Ivor Lewis esophagectomy (MIILE) approach. METHODS: A single-center retrospective cohort study of patients with esophageal adenocarcinoma or stricture treated by either MIAE or MIILE was conducted. MIAE was offered for strictures less than five centimeters or cancers that were American Joint Committee on Cancer (AJCC) Stage ≤ T2 without lymphadenopathy. Patients treated with these surgical techniques were analyzed to assess pre-operative risk, intra and post-operative variables, adverse events, and overall survival. RESULTS: This study included 17 patients undergoing MIAE and 32 patients treated with MIILE. There were a fewer median number of lymph nodes resected (p < 0.001) and shorter operative duration (p < 0.001) for MIAE compared to MIILE. MIAE patients also had significantly higher Charlson Comorbidity Index scores and ACS National Surgical Quality Improvement Program (NSQIP) surgical risk values than MIILE patients (p < 0.05). There was no difference in median estimated blood loss, length of stay, pulmonary or cardiac complications between groups. There was no significant difference in 90-day survival. CONCLUSION: A minimally invasive abdomen-only approach in a specific patient population is comparable in safety to a minimally invasive Ivor Lewis approach, with associated shorter median operative duration. MIAE patients had significantly greater pre-operative comorbidities and higher calculated peri-operative risk of complication but demonstrated similar post-operative outcomes. This suggests that MIAE may be a suitable surgical approach for treating gastroesophageal adenocarcinoma or stricture in patients deemed unsuitable for MIILE.

A Cohort Study on Prognostic Factors for Laser Interstitial Thermal Therapy Success in Newly Diagnosed Glioblastoma.

BACKGROUND: Laser interstitial thermal therapy (LITT) is a promising approach for cytoreduction of deep-seated gliomas. However, parameters contributing to treatment success remain unclear. OBJECTIVE: To identify extent of ablation (EOA) and time to chemotherapy (TTC) as predictors of improved overall and progression-free survival (OS, PFS) and suggest laser parameters to achieve optimal EOA. METHODS: Demographic, clinical, and survival data were collected retrospectively from 20 patients undergoing LITT for newly diagnosed glioblastoma (nGBM). EOA was calculated through magnetic resonance imaging-based volumetric analysis. Kaplan-Meier and multivariate Cox regression were used to examine the relationship between EOA with OS and PFS accounting for covariates (age, isocitrate dehydrogenase-1 (IDH1) mutation, O6-methylguanine-DNA methyltransferase hypermethylation). The effect of laser thermodynamic parameters (power, energy, time) on EOA was identified through linear regression. RESULTS: Median OS and PFS for the entire cohort were 36.2 and 3.5 mo respectively. Patient's with >70% EOA had significantly improved PFS compared to ≤70% EOA (5.2 vs 2.3 mo, P = .01) and trended toward improved OS (36.2 vs 11 mo, P = .07) on univariate and multivariate analysis. Total laser power was a significant predictor for increased EOA when accounting for preoperative lesion volume (P = .001). Chemotherapy within 16 d of surgery significantly predicted improved PFS compared to delaying chemotherapy (9.4 vs 3.1 mo, P = .009). CONCLUSION: Increased EOA was a predictor of improved PFS with evidence of a trend toward improved OS in LITT treatment of nGBM. A strategy favoring higher laser power during tumor ablation may achieve optimal EOA. Early transition to chemotherapy after LITT improves PFS.

Sarcoidosis-Lymphoma Syndrome Presenting As Bony Vertebral Metastasis: A Case Report and Literature Review.

Sarcoidosis preceding a diagnosis of lymphoma has been a reported phenomenon termed sarcoidosis-lymphoma syndrome. Skeletal metastasis is extremely rare. Here, we detail a case of sarcoidosis-lymphoma syndrome presenting as a lumbar vertebral metastasis with suspected associated intracranial lesions. A 72-year-old man with a history of follicular lymphoma presented with symptomatic central nervous system (CNS) lesions with concurrent lumbar vertebral metastases visualized with CT and MRI. Rituximab, cyclophosphamide, doxorubicin hydrochloride, vincristine sulfate, and prednisone (R-CHOP) with dexamethasone treatment resulted in significant radiographic regression of his intracranial lesions with dramatic symptomatic improvement. Out of concern for compression fracture of his lytic lumbar lesions, kyphoplasty with biopsy was performed showing lymphocytes that were positive for cluster-of-differentiation 10 (CD10), CD20, and B-cell lymphoma 2 (Bcl2). The patient was diagnosed with CNS and vertebral sarcoidosis-lymphoma syndrome and began treatment with high-dose methotrexate. Including the present case, only four occurrences of sarcoidosis-lymphoma syndrome with bony involvement have been described. We detail our own experience and summarize all previous literature. While rare, sarcoidosis-lymphoma may present with CNS and lytic bone involvement; in these cases, symptomatic severity, as well as an effective response to steroid treatment, underscore the importance of an accurate and prompt diagnosis.

Adult Intracranial Myxoid Mesenchymal Tumor with EWSR1-ATF1 Gene Fusion.

BACKGROUND: Intracranial myxoid mesenchymal tumors (IMMTs) carrying an EWSR1-CREB gene family fusion are extremely rare and have only been identified in 10 previous reports. All but one has been found in children or young adults. Although there appear to be similarities to a myxoid variant of angiomatoid fibrous histiocytoma (AFH), clear histologic differences exist that appear to distinguish IMMTs as a distinct and novel entity. Previous reports have lacked detailed long-term follow-up and recommendations regarding treatment approach. CASE DESCRIPTION: This case describes a 48-year-old woman who presented with a left intraventricular mass that was identified on histology as an IMMT with an EWSR1-ATF1 gene fusion. After initial resection, the tumor demonstrated local recurrence. Repeat resection was performed followed by immediate demonstration of local and distant tumor recurrence. Histologic analysis of the tumor demonstrated a myxoid mesenchymal tumor distinct from AFH. Fractionated stereotactic radiation therapy was administered after the second resection, and tumor control was achieved at 1 year. CONCLUSIONS: Intracranial myxoid mesenchymal tumor is a novel and rare entity that has been previously identified in only 10 cases. This case is particularly remarkable because it is only the second IMMT case to occur in a middle-aged adult and shares striking similarities in clinical presentation to the previously reported case. Given the aggressive recurrence seen with the presented case, we recommend the treatment plan to be surgical resection followed by adjuvant radiation therapy.

Investigating the host binding signature on the Plasmodium falciparum PfEMP1 protein family.

The Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family plays a central role in antigenic variation and cytoadhesion of P. falciparum infected erythrocytes. PfEMP1 proteins/var genes are classified into three main subfamilies (UpsA, UpsB, and UpsC) that are hypothesized to have different roles in binding and disease. To investigate whether these subfamilies have diverged in binding specificity and test if binding could be predicted by adhesion domain classification, we generated a panel of 19 parasite lines that primarily expressed a single dominant var transcript and assayed binding against 12 known host receptors. By limited dilution cloning, only UpsB and UpsC var genes were isolated, indicating that UpsA var gene expression is rare under in vitro culture conditions. Consequently, three UpsA variants were obtained by rosette purification and selection with specific monoclonal antibodies to create a more representative panel. Binding assays showed that CD36 was the most common adhesion partner of the parasite panel, followed by ICAM-1 and TSP-1, and that CD36 and ICAM-1 binding variants were highly predicted by adhesion domain sequence classification. Binding to other host receptors, including CSA, VCAM-1, HABP1, CD31/PECAM, E-selectin, Endoglin, CHO receptor "X", and Fractalkine, was rare or absent. Our findings identify a category of larger PfEMP1 proteins that are under dual selection for ICAM-1 and CD36 binding. They also support that the UpsA group, in contrast to UpsB and UpsC var genes, has diverged from binding to the major microvasculature receptor CD36 and likely uses other mechanisms to sequester in the microvasculature. These results demonstrate that CD36 and ICAM-1 have left strong signatures of selection on the PfEMP1 family that can be detected by adhesion domain sequence classification and have implications for how this family of proteins is specializing to exploit hosts with varying levels of anti-malaria immunity.