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A 540° posterior-anterior-posterior approach for 360° fused rigid severe cervical kyphosis: patient series

Qiang Jian, Zhenlei Liu, Wanru Duan, Jian Guan, Fengzeng Jian, and Zan Chen

BACKGROUND

Treatment of severe rigid 360° fused cervical kyphosis (CK) is challenging and often requires a combined approach for ankylosis release, establishment of sagittal balance, and fixation with fusion.

OBSERVATIONS

四医源性患者360°融合严重的国际扶轮gid CK (Cobb angle ≥40°) were enrolled for this retrospective analysis. All patients in the case series were female, with an average age of 27 years. All patients previously underwent posterior laminectomy/laminoplasty and cervical tumor resection when they were children (13–17 years). They underwent correction surgery with a 540° posterior-anterior-posterior approach. Preoperative and final follow-up radiography and computed tomography (CT) were used to evaluate kyphosis correction, internal fixation implants, and bone fusion. The preoperative and final follow-up average C2–7 Cobb angles were −32.4° ± 12.0° and 5.3° ± 7.1°, respectively. Preoperative and final follow-up CK angles averaged −47.2° ± 7.4° and −0.9° ± 16.1°, respectively. The mean correction angle was 46.3° ± 9.6°. At final follow-up, CT showed stable fixation and solid bone fusion.

LESSONS

The rare iatrogenic severe kyphosis with 360° ankylosis requires a combined approach. The 540° posterior-anterior-posterior approach can completely release the bony fusion, and the CK can be corrected using an anterior plate. This technique can achieve good results and is an effective strategy.

InJournal of Neurosurgery: Case Lessons Volume 3 (2022): Issue 3 (Jan 2022)

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Prognostic role of mitochondrial pyruvate carrier in isocitrate dehydrogenase–mutant glioma

Michael Karsy, Jian Guan, and L. Eric Huang

OBJECTIVE

Gliomas are one of the most common types of primary brain tumors. Recent studies have supported the importance of key genetic alterations, including isocitrate dehydrogenase (IDH) mutations and 1p19q codeletion, in glioma prognosis. Mutant IDH produces 2-hydroxyglutarate from α-ketoglutarate, a key metabolite of the Krebs cycle. The mitochondrial pyruvate carrier (MPC) is composed of MPC1 and MPC2 subunits and is functionally essential for the Krebs cycle. The authors sought to explore the impact ofMPC1andMPC2expression on patient prognosis.

开云体育世界杯赔率

Genomic and clinical data in patients with lower-grade glioma (WHO grades II and III) from The Cancer Genome Atlas (TCGA) were evaluated using Kaplan-Meier analysis and hazards modeling. Validation was conducted with additional data sets, including glioblastoma.

RESULTS

A total of 286 patients with lower-grade glioma (mean age 42.7 ± 13.5 years, 55.6% males) included 54 cases of IDH–wild type (18.9%); 140 cases of IDH-mutant, 1p19q-intact (49.0%); and 85 cases of IDH-mutant, 1p19q-codeleted (29.7%) tumors. Kaplan-Meier analysis showed that anMPC1z-score > 0 distinguished better survival, particularly in IDH-mutant (p < 0.01) but not IDH–wild type tumors. Conversely, anMPC2z-score > 0 identified worsened survival, particularly in IDH-mutant (p < 0.01) but not IDH–wild type tumors. Consistently, neitherMPC1norMPC2was predictive in a glioblastoma data set containing 5% IDH-mutant cases. Within the IDH-stratified lower-grade glioma data set,MPC1status distinguished improved survival in 1p19q-codeleted tumors (p < 0.05), whereasMPC2expression delineated worsened survival in 1p19q-intact tumors (p < 0.01). A hazards model identified IDH and 1p19q status, age (p = 0.01, HR = 1.03), Karnofsky Performance Scale (KPS) score (p = 0.03, HR = 0.97), andMPC1(p = 0.003, HR = 0.52) but notMPC2(p = 0.38) as key variables affecting overall survival. Further validation confirmedMPC1as an independent predictor of lower-grade glioma. A clinical risk score using IDH and 1p19q status, age, KPS score, andMPC1andMPC2z-scores defined 4 risk categories for lower-grade glioma; this score was validated using a secondary glioma data set.

CONCLUSIONS

These results support the importance of MPC, especiallyMPC1, in improving prognostication of IDH-mutant tumors. The generation of a risk score system directly translates this finding to clinical application; however, further research to improve the molecular understanding of the role of MPC in the metabologenomic regulation of gliomas is warranted.

InJournal of Neurosurgery Volume 130: Issue 1 (Jan 2019)

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Chiari-related hydrocephalus: assessment of clinical risk factors in a cohort of 297 consecutive patients

Jian Guan, Jay Riva-Cambrin, and Douglas L. Brockmeyer

OBJECTIVE

Patients treated for Chiari I malformation (CM-I) with posterior fossa decompression (PFD) may occasionally and unpredictably develop postoperative hydrocephalus. The clinical risk factors predictive of this type of Chiari-related hydrocephalus (CRH) are unknown. The authors' objective was to evaluate their experience to identify risk factors that may predict which of these patients undergoing PFD will develop CRH after surgery.

开云体育世界杯赔率

The authors performed a retrospective clinical chart review of all patients who underwent PFD surgery and duraplasty for CM-I at the Primary Children's Hospital in Utah from June 1, 2005, through May 31, 2015. Patients were dichotomized based on the need for long-term CSF diversion after PFD. Analysis included both univariate and multivariable logistic regression analyses.

RESULTS

The authors identified 297 decompressive surgeries over the period of the study, 22 of which required long-term postoperative CSF diversion. On multivariable analysis, age < 6 years old (OR 3.342, 95% CI 1.282–8.713), higher intraoperative blood loss (OR 1.003, 95% CI 1.001–1.006), and the presence of a fourth ventricular web (OR 3.752, 95% CI 1.306–10.783) were significantly associated with the need for long-term CSF diversion after decompressive surgery.

CONCLUSIONS

Younger patients, those with extensive intraoperative blood loss, and those found during surgery to have a fourth ventricular web were at higher risk for the development of CRH. Clinicians should be alert to evidence of CRH in this patient population after PFD surgery.

InNeurosurgical Focus Volume 41 (2016): Issue 5 (Nov 2016): Pediatric Hydrocephalus

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Sequelae and management of radiation vasculopathy in neurosurgical patients

Spencer Twitchell, Michael Karsy, Jian Guan, William T. Couldwell, and Philipp Taussky

术语“辐射血管病变”定义了一个异性geneous and poorly defined complex of vessel injury due to radiation. Radiation vasculopathy remains underrecognized and poorly treated with respect to head and neck radiotherapy. Distinct injury patterns to small (≤ 100-μm), medium (> 100-μm), and large (> 500-μm) vessels can occur, resulting in carotid stenosis, intracranial stenosis, and vascular anomalies (e.g., cavernous malformations, aneurysms). Because of the lack of clinical evidence and guidelines, treatment plans involve medical management, carotid endarterectomy, and carotid artery stenting and are developed on a patient-by-patient basis. In this review, the authors discuss the current pathophysiology, imaging, clinical impact, and potential treatment strategies of radiation vasculopathy with clinical pertinence to practicing neurosurgeons and neurologists. A review of 4 patients with prior head and neck tumors in whom delayed radiation vasculopathy developed after radiotherapy demonstrates the application of various treatment options in a case-by-case manner. Earlier recognition of radiation vasculopathy disease patterns may enable earlier initiation of treatment and monitoring for complications. Standardized terminology and treatments may assist with improving clinical outcomes.

InJournal of Neurosurgery Volume 130: Issue 6 (Jun 2019)

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评估的成本动因和成本变化lumbar interbody fusion procedures using the Value Driven Outcomes database

Spencer Twitchell, Michael Karsy, Jared Reese, Jian Guan, William T. Couldwell, Andrew Dailey, and Erica F. Bisson

OBJECTIVE

Efforts to examine the value of care—combining both costs and quality—are gaining importance in the current health care climate. This thrust is particularly evident in treating common spinal disease where both incidences and costs are generally high and practice patterns are variable. It is often challenging to obtain direct surgical costs for these analyses, which hinders the understanding of cost drivers and cost variation. Using a novel tool, the authors sought to understand the costs of posterior lumbar arthrodesis with interbody devices.

开云体育世界杯赔率

The Value Driven Outcomes (VDO) database at the University of Utah was used to evaluate the care of patients who underwent open or minimally invasive surgery (MIS), 1- and 2-level lumbar spine fusion (Current Procedural Terminology code 22263). Patients treated from January 2012 through June 2017 were included.

RESULTS

A total of 276 patients (mean age 58.9 ± 12.4 years) were identified; 46.7% of patients were men. Most patients (82.2%) underwent 1-level fusion. Thirteen patients (4.7%) had major complications and 11 (4.1%) had minor complications. MIS (β = 0.16, p = 0.002), length of stay (β = 0.47, p = 0.0001), and number of operated levels (β = 0.37, p = 0.0001) predicted costs in a multivariable analysis. Supplies and implants (55%) and facility cost (36%) accounted for most of the expenditure. Other costs included pharmacy (7%), laboratory (1%), and imaging (1%).

CONCLUSIONS

These results provide direct cost accounting for lumbar fusion procedures using the VDO database. Efforts to improve the value of lumbar surgery should focus on high cost areas, i.e., facility and supplies/implant.

InNeurosurgical Focus Volume 44: Issue 5 (May 2018): Neurosurgical Economics and Cost-Effectiveness

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The genetic basis of intradural spinal tumors and its impact on clinical treatment

Michael Karsy, Jian Guan, Walavan Sivakumar, Jayson A. Neil, Meic H. Schmidt, and Mark A. Mahan

Genetic alterations in the cells of intradural spinal tumors can have a significant impact on the treatment options, counseling, and prognosis for patients. Although surgery is the primary therapy for most intradural tumors, radiochemothera-peutic modalities and targeted interventions play an ever-evolving role in treating aggressive cancers and in addressing cancer recurrence in long-term survivors. Recent studies have helped delineate specific genetic and molecular differences between intradural spinal tumors and their intracranial counterparts and have also identified significant variation in therapeutic effects on these tumors. This review discusses the genetic and molecular alterations in the most common intradural spinal tumors in both adult and pediatrie patients, including nerve sheath tumors (that is, neurofibroma and schwannoma), meningioma, ependymoma, astrocytoma (that is, low-grade glioma, anaplastic astrocytoma, and glioblastoma), hemangioblastoma, and medulloblastoma. It also examines the genetics of metastatic tumors to the spinal cord, arising either from the CNS or from systemic sources. Importantly, the impact of this knowledge on therapeutic options and its application to clinical practice are discussed.

InNeurosurgical Focus Volume 39 (2015): Issue 2 (Aug 2015): Intradural Spinal Tumors

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Factors influencing management of unruptured intracranial aneurysms: an analysis of 424 consecutive patients

Jian Guan, Michael Karsy, William T. Couldwell, Richard H. Schmidt, Philipp Taussky, Joel D. MacDonald, and Min S. Park

OBJECTIVE

The choice between treating and observing unruptured intracranial aneurysms is often difficult, with little guidance on which variables should influence decision making on a patient-by-patient basis. Here, the authors compared demographic variables, aneurysm-related variables, and comorbidities in patients who received microsurgical or endovascular treatment and those who were conservatively managed to determine which factors push the surgeon toward recommending treatment.

开云体育世界杯赔率

A retrospective chart review was conducted of all patients diagnosed with an unruptured intracranial aneurysm at their institution between January 1, 2013, and January 1, 2016. These patients were dichotomized based on whether their aneurysm was treated. Demographic, geographic, socioeconomic, comorbidity, and aneurysm-related information was analyzed to assess which factors were associated with the decision to treat.

RESULTS

A total of 424 patients were identified, 163 who were treated surgically or endovascularly and 261 who were managed conservatively. In a multivariable model, an age < 65 years (OR 2.913, 95% CI 1.298–6.541, p = 0.010), a lower Charlson Comorbidity Index (OR 1.536, 95% CI 1.274–1.855, p < 0.001), a larger aneurysm size (OR 1.176, 95% CI 1.100–1.257, p < 0.001), multiple aneurysms (OR 2.093, 95% CI 1.121–3.907, p = 0.020), a white race (OR 2.288, 95% CI 1.245–4.204, p = 0.008), and living further from the medical center (OR 2.125, 95% CI 1.281–3.522, p = 0.003) were all associated with the decision to treat rather than observe.

CONCLUSIONS

而有几个因素将considered in the decision to treat unruptured intracranial aneurysms, including age, Charlson Comorbidity Index, aneurysm size, and multiple aneurysms, other factors such as race and proximity to the medical center were unanticipated. Further studies are needed to identify such biases in patient treatment and improve treatment delineation based on patient-specific aneurysm rupture risk.

InJournal of Neurosurgery Volume 127: Issue 1 (Jul 2017)

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Letter to the Editor. Rotational thromboelastometry-guided transfusion protocol

Thomas J. Buell, Davis G. Taylor, Ching-Jen Chen, and Bhiken I. Naik

InJournal of Neurosurgery: Spine Volume 29: Issue 1 (Jul 2018)

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Utility of intraoperative rotational thromboelastometry in thoracolumbar deformity surgery

Jian Guan, Chad D. Cole, Meic H. Schmidt, and Andrew T. Dailey

OBJECTIVE

Blood loss during surgery for thoracolumbar scoliosis often requires blood product transfusion. Rotational thromboelastometry (ROTEM) has enabled the more targeted treatment of coagulopathy, but its use in deformity surgery has received limited study. The authors investigated whether the use of ROTEM reduces transfusion requirements in this case-control study of thoracolumbar deformity surgery.

开云体育世界杯赔率

Data were prospectively collected on all patients who received ROTEM-guided blood product management during long-segment (≥ 7 levels) posterior thoracolumbar fusion procedures at a single institution from April 2015 to February 2016. Patients were matched with a group of historical controls who did not receive ROTEM-guided therapy according to age, fusion segments, number of osteotomies, and number of interbody fusion levels. Demographic, intraoperative, and postoperative transfusion requirements were collected on all patients. Univariate analysis of ROTEM status and multiple linear regression analysis of the factors associated with total in-hospital transfusion volume were performed, with p < 0.05 considered to indicate statistical significance.

RESULTS

15个病人ROTEM-guided疗法were identified and matched with 15 non-ROTEM controls. The mean number of fusion levels was 11 among all patients, with no significant differences between groups in terms of fusion levels, osteotomy levels, interbody fusion levels, or other demographic factors. Patients in the non-ROTEM group required significantly more total blood products during their hospitalization than patients in the ROTEM group (8.5 ± 4.2 units vs 3.71 ± 2.8 units; p = 0.001). Multiple linear regression analysis showed that the use of ROTEM (p = 0.016) and a lower number of fused levels (p = 0.022) were associated with lower in-hospital transfusion volumes.

CONCLUSIONS

ROTEM use during thoracolumbar deformity correction is associated with lower transfusion requirements. Further investigation will better define the role of ROTEM in transfusion during deformity surgery.

InJournal of Neurosurgery: Spine Volume 27 (2017): Issue 5 (Nov 2017)

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Comparing clinical outcomes of repeat discectomy versus fusion for recurrent disc herniation utilizing the N2QOD

Jian Guan, Vijay M. Ravindra, Meic H. Schmidt, Andrew T. Dailey, Robert S. Hood, and Erica F. Bisson

OBJECTIVE

Recurrent lumbar disc herniation (RLDH) is a significant cause of morbidity in patients undergoing lumbar discectomy and has been reported to occur in up to 18% of cases. While repeat discectomy is often successful in treating these patients, concern over repeat RLDH may lead surgeons to advocate instrumented fusion even in the absence of instability. The authors' goal was to compare clinical outcomes for patients undergoing repeat discectomy versus instrumented fusion for RLDH.

开云体育世界杯赔率

The authors used the National Neurosurgery Quality and Outcomes Database (N2QOD) to assess outcomes of patients who underwent repeat discectomy versus instrumented fusion at a single institution from 2012 to 2015. Primary outcomes included Oswestry Disability Index (ODI) score, visual analog scale (VAS) score, and quality-adjusted life year (QALY) measures. Secondary outcomes included hospital length of stay, discharge status, and hospital charges.

RESULTS

The authors identified 25 repeat discectomy and 12 instrumented fusion patients with 3- and 12-month follow-up records. The groups had similar ODI and VAS scores and QALY measurements at 3 and 12 months. Patients in the instrumented fusion group had significantly longer hospitalizations (3.7 days vs 1.0 days, p < 0.001) and operative times (229.6 minutes vs 82.7 minutes, p < 0.001). They were also more likely to be female (p = 0.020) and to be discharged to inpatient rehabilitation instead of home (p = 0.036). Hospital charges for the instrumented fusion group were also significantly higher ($54,458.29 vs $11,567.05, p < 0.001). Rates of reoperation were higher in the repeat discectomy group (12% vs 0%), but the difference was not statistically significant (p = 0.211).

CONCLUSIONS

Repeat discectomy and instrumented fusion result in similar clinical outcomes at short-term follow-up. Patients undergoing repeat discectomy had significantly shorter operative times and length of stay, and they incurred dramatically lower hospital charges. They were also less likely to require acute rehabilitation postoperatively. Further research is needed to compare these two management strategies.

InJournal of Neurosurgery: Spine Volume 26 (2017): Issue 1 (Jan 2017)

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