CSF-Related Complications After Intradural Spinal Tumor Surgery: Utility of an Autologous Fat Graft

Single-Center Experience of Resection of 120 Cases of Intradural Spinal Tumors

BACKGROUND

Our study presents a single-center experience of resection of intradural spinal tumors either with or without using intraoperative computed tomography-based registration and microscope-based augmented reality (AR). Microscope-based AR was recently described for improved orientation in the operative field in spine surgery, using superimposed images of segmented structures of interest in a two-dimensional or three-dimensional mode.

METHODS

All patients who underwent surgery for resection of intradural spinal tumors at our department were retrospectively included in the study. Clinical outcomes in terms of postoperative neurologic deficits and complications were evaluated, as well as neuroradiologic outcomes for tumor remnants and recurrence.

RESULTS

112 patients (57 female, 55 male; median age 55.8 ± 17.8 years) who underwent 120 surgeries for resection of intradural spinal tumors with the use of intraoperative neuromonitoring were included in the study, with a median follow-up of 39 ± 34.4 months. Nine patients died during the follow-up for reasons unrelated to surgery. The most common tumors were meningioma (n = 41), schwannoma (n = 37), myopapillary ependymomas (n = 12), ependymomas (n = 10), and others (20). Tumors were in the thoracic spine (n = 46), lumbar spine (n = 39), cervical spine (n = 32), lumbosacral spine (n = 1), thoracic and lumbar spine (n = 1), and 1 tumor in the cervical, thoracic, and lumbar spine. Four biopsies were performed, 10 partial resections, 13 subtotal resections, and 93 gross total resections. Laminectomy was the common approach. In 79 cases, patients experienced neurologic deficits before surgery, with ataxia and paraparesis as the most common ones. After surgery, 67 patients were unchanged, 49 improved and 4 worsened. Operative time, extent of resection, clinical outcome, and complication rate did not differ between the AR and non-AR groups. However, the use of AR improved orientation in the operative field by identification of important neurovascular structures.

CONCLUSIONS

High rates of gross total resection with favorable neurologic outcomes in most patients as well as low recurrence rates with comparable complication rates were noted in our single-center experience. AR improved intraoperative orientation and increased surgeons' comfort by enabling early identification of important anatomic structures; however, clinical and radiologic outcomes did not differ, when AR was not used.

Clinical management of dural defects: A review

Dural defects are common in spinal and cranial neurosurgery. A series of complications, such as cerebrospinal fluid leakage, occur after rupture of the dura. Therefore, treatment strategies are necessary to reduce or avoid complications. This review comprehensively summarizes the common causes, risk factors, clinical complications, and repair methods of dural defects. The latest research progress on dural repair methods and materials is summarized, including direct sutures, grafts, biomaterials, non-biomaterial materials, and composites formed by different materials. The characteristics and efficacy of these dural substitutes are reviewed, and these materials and methods are systematically evaluated. Finally, the best methods for dural repair and the challenges and future prospects of new dural repair materials are discussed.

Clinical and Biomechanical Study of Laminoplasty for Thoracic and Lumbar Intradural Tumors

(1) Background: Primary intraspinal tumors account for 2-15% of all central nervous system (CNS) tumors. Most intraspinal tumors are benign, and about 40% of them occur intradurally, for which early surgery is the preferred treatment. Laminectomy with pedicle screw fixation is the conventional surgical treatment. However, laminectomy with pedicle screw fixation is likely to reduce the spinal range of motion (ROM), with many other complications, although it can maintain the stability of the spine. The aim of this study is to determine whether laminoplasty as a new surgical approach for thoracic and lumbar intradural tumors is superior to laminectomy in preserving spinal ROM, maintaining spinal stability and reducing postoperative complications. (2) Methods: We retrospectively analyzed 50 patients who received intradural tumor resection, including 23 who received traditional laminectomy with pedicle screw fixation and 27 who received new laminoplasty. Spinal ROM was evaluated by lumbar flexion/extension radiograph and biomechanical evaluation. Spinal stability was evaluated by imaging observations of the spinal Cobb angle and laminar bone fusion. Postoperative complications were evaluated according to cerebrospinal fluid (CSF) leakage and the length of hospital stay. (3) Results: Compared with the laminectomy group, patients in the laminoplasty group exhibited a better spinal ROM (31.6 ± 12.0° vs. 21.7 ± 11.8°, p = 0.013), a smaller Cobb angle (9.6 ± 4.3 vs. 12.5 ± 5.3, p = 0.034), a lower incidence of CSF leakage (4/14.8% vs. 11/47.8%, p = 0.015), and a shorter length of hospital stay (13.1 ± 1.8 vs. 15.1 ± 2.3 days, p = 0.001). Most patients in the laminoplasty group had satisfactory bone fusion. The biomechanical experiment also demonstrated that spinal ROM in laminoplasty was larger than that in the laminectomy group. (4) Conclusions: Compared with the traditional surgery, the new laminoplasty surgery can better maintain the stability of the spine, preserve spinal ROM, and reduce postoperative complications. It is a surgical method that can be clinically popularized.

Tensile properties of human spinal dura mater and pericranium

Autologous pericranium is a promising dural graft material. An optimal graft should exhibit similar mechanical properties to the native dura, but the mechanical properties of human pericranium have not been characterized, and studies of the biomechanical performance of human spinal dura are limited. The primary aim of this study was to measure the tensile structural and material properties of the pericranium, in the longitudinal and circumferential directions, and of the dura in each spinal region (cervical, thoracic and lumbar) and in three directions (longitudinal anterior and posterior, and circumferential). The secondary aim was to determine corresponding constitutive stress-strain equations using a one-term Ogden model. A total of 146 specimens were tested from 7 cadavers. Linear regression models assessed the effect of tissue type, region, and orientation on the structural and material properties. Pericranium was isotropic, while spinal dura was anisotropic with higher stiffness and strength in the longitudinal than the circumferential direction. Pericranium had lower strength and modulus than spinal dura across all regions in the longitudinal direction but was stronger and stiffer than dura in the circumferential direction. Spinal dura and pericranium had similar strain at peak force, toe, and yield, across all regions and directions. Human pericranium exhibits isotropic mechanical behavior that lies between that of the longitudinal and circumferential spinal dura. Further studies are required to determine if pericranium grafts behave like native dura under in vivo loading conditions. The Ogden parameters reported may be used for computational modeling of the central nervous system. Graphical abstract.

Perioperative lumbar subarachnoid drainage could not prevent postoperative CSF leakage after spinal cord tumor resection using an artificial dura mater

BACKGROUND

Cerebrospinal fluid (CSF) leakage occurs in patients who undergo dural repair using artificial dura mater. This study aimed to determine if perioperative lumbar subarachnoid drainage could reduce the incidence of postoperative CSF leakage in cases of dural repair using artificial dura mater.

METHODS

We retrospectively analyzed 84 patients (41 men, 43 women; mean age, 52.2 ± 20.1 years) who underwent intradural spinal cord tumor resection and dural repair using artificial dura mater. These patients were divided according to whether they underwent perioperative lumbar subarachnoid drainage (39 patients: D group) or had no drainage (45 patients: ND group). The incidence of radiographic and symptomatic CSF leakage as well as baseline characteristics and operative data were compared between the two groups.

RESULTS

Radiographic CSF leakage was observed in 21 patients (25.0%), including 10 (25.6%) in the D group and 11 (24.4%) in the ND group. Symptomatic CSF leakage was observed in 12 patients (14.2%), including six (15,4%) in the D group and 11 (13.3%) in the ND group. There were no significant differences in the incidence of subcutaneous CSF accumulation and symptomatic CSF leakage between the two groups. In cases with symptomatic CSF leakage, the onset time of CSF leakage tended to be earlier (5.7 days vs 15.7 days), and the treatment period tended to be longer (5.8 weeks vs 2.8 weeks) in the ND group than in the D group.

CONCLUSIONS

Perioperative lumbar subarachnoid drainage did not reduce the incidence of either radiographic or symptomatic CSF leakage. However, it might shorten the treatment period and reduce refractory CSF leakage, which requires multiple treatments over a long period.

Complication Avoidance in Surgical Management of Vertebral Column Tumors

The surgical management of spinal tumors has grown increasingly complex as treatment algorithms for both primary bone tumors of the spine and metastatic spinal disease have evolved in response to novel surgical techniques, rising complication rates, and additional data concerning adjunct therapies. In this review, we discuss actionable interventions for improved patient safety in the operative care for spinal tumors. Strategies for complication avoidance in the preoperative, intraoperative, and postoperative settings are discussed for approach-related morbidities, intraoperative hemorrhage, wound healing complications, cerebrospinal fluid (CSF) leak, thromboembolism, and failure of instrumentation and fusion. These strategies center on themes such as pre-operative imaging review and medical optimization, surgical dissection informed by meticulous attention to anatomic boundaries, and fastidious wound closure followed by thorough post-operative care.

Factors Influencing Surgical Outcomes for Intradural Spinal Tumours: A Single-Centre Retrospective Cohort Study

Introduction

Intradural spinal tumours are relatively uncommon tumours of the central nervous system. In this study, we sought to assess our current practice and determine the factors which affect the surgical outcomes of intradural spinal tumour resection.

Methods

All consecutive patients who underwent surgical resection of intradural spinal tumours from December 2011 to November 2018 were retrospectively reviewed. The Modified McCormick Scale (MMS) was used to grade patients’ neurological status both pre-operatively and at the latest follow-up. The associations between changes in MMS and variables such as patient demographics, tumour location, number and experience of consultants involved in the procedure, use of intraoperative neuro-monitoring, bony spinal exposure and dural closure methods were assessed. A multivariable binary logistic regression model was performed to identify independent predictors of improvements in MMS. All analyses were performed using IBM SPSS 22 (IBM Corp. Armonk, NY), with p<0.05 deemed to be indicative of statistical significance throughout.

Results

A total of 145 patients met the inclusion criteria, with a median age of 56.5 years; of whom 119 had extramedullary tumours and 26 had intramedullary tumours. Methods of dural closure were variable, and there was an increasing trend over time towards using the laminoplasty approach for bony exposure. Neither the experience of consultants (p=0.991) nor the number of consultants involved (p=0.084) was found to be significantly associated with the change in MMS, with the strongest predictor being the baseline MMS (p<0.001). Patients who had adjuvant therapy were also significantly more likely to have a poorer neurological outcome (p=0.001).

Conclusion

A good neurological baseline is a significant positive predictor of an improved functional outcome. The number and seniority of consultant surgeons involved in intradural spinal tumour resections did not significantly alter the postoperative outcomes of patients in our single-unit retrospective study.

Microsurgical Resection of Radiation-Induced Cervical Spinal Intradural Extramedullary Meningioma: Dural Splitting Resection

Spinal meningiomas constitute 10% of all meningiomas. They most commonly rise in the thoracic spine and are most common in middle aged women; symptoms include progressive myelopathy.^1,2 Radiation induced/radiotherapy-associated cranial meningiomas are well described with aggressive behavior; however, radiation-induced spinal meningiomas are extremely rare in the literature.^3-7 Our patient had a history of Hodgkin lymphoma treated with neck radiation, and thyroid cancer treated with radioactive iodine/thyroidectomy. He presented with neck pain and myelopathy from a large intradural, extramedullary tumor compressing the spinal cord (C3-C5). He had a prevertebral phlegmon that was resolved with antibiotics prior to surgery. Intraoperative neurophysiological electrodes were placed for somatosensory-evoked potential and motor-evoked potential monitoring. C3-C5 bilateral laminectomies were performed (Video 1); dura was incised over the tumor. Tumor attachments to the dura were coagulated and divided. The tumor was dissected microsurgically from the spinal cord and nerve roots. The dural layer involved by the tumor was split and resected from the uninvolved dura, achieving tumor resection. Postoperatively, the patient's myelopathy resolved. He has been followed for a 1 year now with mangetic resonance imaging scans of the cervical spine ± contrast every 6 months. To our knowledge, this is the first operative video describing resection of a spinal meningioma, which happens to be radiation-induced, using a dural splitting technique to achieve better resection and prevent tumor recurrence. The alternative treatment would be to leaving the inner layer of dura, coagulation, or excising both layers and performing duraplasty. Both alternative options, however, would increase the risk of recurrence and spinal fluid leak. Cervical spine meningiomas with spinal cord compression and myelopathy should be resected to prevent further neurological decline. Dural splitting can be utilized to achieve "radical" tumor resection to prevent recurrence, which is particularly important if the tumor is aggressive and recurrent, as is the case in radiation-induced/radiotherapy-associated meningiomas. Upon dural closure, we applied autologous fat tissue along with fibrin glue to avoid spinal fluid leak as we published earlier.⁸ The patient consented to the procedure and publication of his image.

Effectiveness of Repair Techniques for Spinal Dural Tears: A Systematic Review

BACKGROUND

Incidental or intentional durotomy in spine surgery is associated with a risk of cerebrospinal fluid (CSF) leakage and reoperation. Several strategies have been introduced, but the incomplete closure is still relatively frequent and troublesome. In this study, we review current evidence on spinal dural repair strategies and evaluate their efficacy.

METHODS

PubMed, Web of Science, and Scopus were used to search primary studies about the repair of the spinal dura with different techniques. Of 265 articles found, 11 studies, which specified repair techniques and postoperative outcomes, were included for qualitative and quantitative analysis. The primary outcomes were CSF leakage and postoperative infection.

RESULTS

The outcomes of different dural repair techniques were available in 776 cases. Pooled analysis of 11 studies demonstrated that the most commonly used technique was a combination of primary closure, patch or graft, and sealant (22.7%, 176/776). A combination of primary closure and patch or graft resulted in the lowest rate of CSF leakage (5.5%, 7/128). In this study, sealants as an adjunct to primary closure (13.7%, 18/131) did not significantly reduce the rate of CSF leakage compared with primary closure alone (17.6%, 18/102). The rates of infection and postoperative neurologic deficit were similar regardless of the repair techniques.

CONCLUSIONS

Although the use of sealants has become prevalent, available sealants as an adjunct to primary closure did not reduce the rate of CSF leakage compared with primary closure. The combination of primary closure and patches or grafts could be effective in decreasing postoperative CSF leakage.

The 270° Circumferential Microsurgical Decompression of the Foramen Magnum in Adult Chiari Malformation Type I: Single Surgeon Series of 130 Patients with Syringomyelia, Neurologic, and Headache Outcomes

OBJECTIVE

Chiari malformation type I (CM-I) is a craniocervical junction disorder associated with descent of the cerebellar tonsils >5 mm. The prevalence of CM-I is common, including 0.5%-3.5% in the general population, 0.56%-0.77% on magnetic resonance imaging, and 0.62% in anatomic dissection studies. We sought to measure our surgical outcomes related to resolution/improvement of headaches, neurologic outcomes, and syringomyelia compared with reported adult CM-I studies from 2000-2019.

METHODS

From December 2003 to June 2018, the first author (K.I.A.) performed 270° circumferential decompression on adult (>18 years) patients with CM-I. At admission and follow-up, all parameters were numerically evaluated; headaches were self-reported on the visual analog scale, neurologic condition was evaluated using Karnofsky Performance Status and European Myelopathy Score, and syrinx width (if present) was measured on magnetic resonance imaging by grades I-IV. All parameters were analyzed, compared, and statistically tested. We compared results with our previously reported and updated systematic review of operative adult CM-I studies (studies from 2000 to 2019).

RESULTS

In our series, 118/121 (98%) experienced headache improvements and 100% experienced neurologic improvements. Complete syrinx resolution was experienced by 35/43 (81%); 8 (19%) showed significant improvement. In data from reported studies (2000-2019), only 79% experienced headache resolution, 77% improvement of neurologic status, and 74% resolution/improvement of syrinx (mean).

CONCLUSIONS

Our modified 270° circumferential microsurgical foramen magnum decompression for adult CM-I appears to be beneficial in improvement of outcomes, namely in resolution of the syrinx, neurologic symptoms, and headaches. We also confirm the association of body mass index with CM-I. Further studies are needed to confirm our results.

Microsurgical Resection of Lung Carcinoma Spinal Cord Metastasis: 2-Dimensional Operative Video

This video demonstrates microsurgical resection of intramedullary spinal cord metastasis of lung adenocarcinoma. Lung cancer is the predominant cause of rare metastatic intramedullary involvement of the spinal cord.1-4 Because of severe disabilities, these tumors should be considered for treatment with the goal of complete removal to preserve neurological functioning.5-9  Surgical resection improves symptoms, preserves ambulatory status, and increases survival time twice that of nonsurgical treatments.3,8,10 Surgery can be effective in arresting neurological decline.11,12 To our knowledge, this is the first video report of an intramedullary spinal cord metastasis resection.  A 69-yr-old male with history of lung cancer presented with acute onset left arm abduction, forearm flexion, and hand weakness (3/5) and gait disturbance. Cervical spine MRI revealed C4/C5 nonhomogenously enhancing intramedullary tumor measuring 22 × 10 × 7 mm. Sagittal T2-weighted image demonstrated extensive cord edema.  The C4 and C5 laminectomies were performed. Microsurgical techniques were employed.13-15 Metastasis involved the left lateral aspect of the cord with invasion of 2 left dorsal sensory nerve roots, which were resected. Further transection of the dentate ligament relaxed the spinal cord, enabling safer tumor resection. Pial dissection using bipolar forceps, microscissors, and microdissector enabled tumor delivery. Following resection, dural closure was reinforced with previously harvested fat tissue graft to prevent CSF leak.16  Postoperative MRI revealed complete macroscopic resection with improvement of spinal cord swelling. Patient improved his gate and his left arm motor strength was stable. Subsequently, patient received focal adjuvant radiotherapy. Written consent was obtained directly from the patient.

[Structure and mechanical characteristics of spinal dura mater in different segments of sheep's spine]

Objective

To clarify the structure and biomechanical characteristics of the dura mater of the cervical, thoracic, and lumbar segments of sheep, in order to provide a theoretical reference for the study of artificial dura mater.

Methods

Five adult male white sheep were sacrificed. The dura mater of C ₅, T ₁₀, and L ₃ planes were obtained. The histological HE staining was used to observe the internal structure and the thickness of dura mater; the inner and outer surfaces morphology of the dura was observed by scanning electron microscopy (SEM); transmission electron microscopy (TEM) was used to observe the internal structure of dura mater and to measure the diameter of collagen fibers in each part of dura mater. The dura mater of C ₆, C ₇, T ₁₁, T ₁₂, L ₄, and L ₅ planes were taken for uniaxial biomechanical test, and modulus of elasticity, tensile strength, and elongation at break were measured.

Results

HE staining showed that the thickness of the cervical, thoracic, and lumbar dura mater gradually decreased, and the thickness of the dura mater was (268.19±15.91), (198.16±27.25), (103.74±21.54) μm, respectively, and the differences were significant ( P<0.05). SEM observation showed that there were more collagen fibers and fewer cells on the inner surface of the dura mater, while more cells were distributed on the outer surface, and the cells on the inner and outer surface were stretched along the longitudinal axis. TEM observation showed that the collagen fibers in the dura mater were interlaced and arranged in layers. The collagen fibers in the lamina were arranged in the same direction, and the collagen fibers between the lamina were arranged vertically. The diameters of collagen fibers in the cervical, thoracic, and lumbar dura mater were (68.04±21.00), (64.54±20.64), (60.36±19.65) nm, respectively, and the differences were not significant ( P>0.05). Uniaxial biomechanical tests results showed that there was no significant difference in modulus of elasticity, tensile strength, and elongation at break between the axial and transverse dura mater of the cervical dura mater ( P>0.05); the axial data of thoracic and lumbar segments were significantly larger than the transverse data ( P<0.05). The axial modulus of elasticity, tensile strength, and elongation at break of the dura mater of the cervical, thoracic, and lumbar dura mater were significantly different ( P<0.05) from the transverse ones, and showing a decreasing trend. Among them, the ratio of axial and transverse modulus of elasticity of cervical and thoracic dura were significantly smaller than that of lumbar segment ( P<0.05), and there was no significant difference between cervical segments and thoracic segments ( P>0.05).

Conclusion

The thickness of dura mater in sheep decreased gradually from head to tail. There are more collagen fibers and fewer cells on the inner surface of dura mater, while the outer surface of dura mater is covered by cells. The collagen fiberboard layers in the dura mater are arranged alternately, and have obvious anisotropic biomechanical characteristics, and the anisotropic biomechanical characteristics get more significant from the head to the tail.

Spinal dural closure without suture: Minimizing the risk of CSF leakage with a flat non-penetrating titanium U-clip

BACKGROUND

The classic surgical spinal dural closure technique in surgery on intradural lesions is performed with continuous suture or loose stitches using 4-0 to 6-0 polypropylene monofilament or nylon suture. Dural closure with suture causes irritant damage to the dural/arachnoid interface. The penetrating suture causes new dural holes. Even the needle of the suture can cause harm to the patient and the surgeon. For these reasons, other non-penetrating techniques for dural closure have been sought.

OBJECTIVE

The purpose of this review was to show the efficacy of using the titanium clip (U-clip) (Ligaclip-MCA of Ethicon Endo-Surgery, LLC, Medical GmbH, Norderstedt, Germany) with a flat internal surface in spinal neurosurgical procedures, and to evaluate the effects of its use on post-operative magnetic resonance imaging (MRI).

METHODS

We performed a retrospective analysis of a cohort of 50 consecutive patients who underwent intradural spinal surgeries for intradural spinal lesions in the neurosurgery department of our institution between 2013 and 2018.

RESULTS

The mean follow-up period was 27 months. No patient developed a post-operative cerebrospinal fluid (CSF) dural-cutaneous fistula. CSF leakage was not observed in the control MRIs at 6 weeks.

CONCLUSIONS

We describe, for the first time, the use of this type of U-clip with a flat inner side. The non-penetrating titanium U-clip facilitates effective and rapid dural closure at all spinal levels due to its flat internal face when closed. The U-clips did not cause significant artefacts or distortions on the magnetic resonance imaging.

Microsurgical Resection of Low-Grade Spinal Cord Astrocytoma: 2-Dimensional Operative Video

This video demonstrates microsurgical resection of low-grade (Grade I) thoracic spinal cord astrocytoma. Astrocytomas are the most common pediatric intramedullary tumors and occur secondary to ependymomas in adults.^1,2 The treatment goal should be radical gross total resection while preserving neurological function with intraoperative neuromonitoring.^2-4 To our knowledge, this is the first video report on microsurgical resection of low-grade spinal cord astrocytoma.

 A 58-yr-old female presented with gait disturbances has been featured in this video. A spinal MRI revealed T1/T2 hyperintense intramedullary tumor at T4, suggesting spinal cord astrocytoma versus ependymoma. Dura was opened in the midline and tacked to the surrounding muscle tissue with tacking sutures. The arachnoid was opened separately with microscissors, keeping it intact for closure at the end of surgery. Liga clips were applied to hold the arachnoid to the dura. Myelotomy was done in the midline,⁵ opening the posterior median sulcus over the length of the tumor and extending proximally and distally a few millimeters beyond the tumor.^3,5 The tumor reduction was achieved by coagulation or debulking. Once sufficient debulking was achieved, dissection of the tumor margins toward surrounding cord was performed. Preoperative recording of motor-evoked potentials (MEPs) compared with continuous intraoperative MEPs were essential for preserving the neurological function and quality of life. The intraoperative finding of a clear tumor plane of resection carries positive prognostic significance and reduces the risk of complications.^2,3,6

 A pathohistological diagnosis showed a low-grade (Grade I) spinal cord astrocytoma (pilocytic). Follow-up MRI showed no sign of tumor or recurrence. The patient recovered fully and was neurologically intact.

Written consent was obtained directly from the patient.

SPINAL DUMBBELL EPIDURAL HEMANGIOMA: TWO STAGE/SAME SITTING/SAME POSITION POSTERIOR MICROSURGICAL AND TRANSTHORACIC ENDOSCOPIC RESECTION - CASE REPORT AND REVIEW OF THE LITERATURE

- Spinal dumbbell tumors are defined by a narrowing at the point where they penetrate the intervertebral foramina or dura mater, assuming an hourglass or dumbbell shape. Dumbbell-shaped spinal hemangiomas are extremely rare. We describe a dumbbell spinal tumor (epidural cavernous hemangioma) resected by a 2-stage single-sitting combined approach. We also conduct a substantial literature review of the subject. We present a case of a 78-year-old male who was found to have a homogeneously enhancing, dumbbell-shaped, intraspinal, extradural tumor mass extending into the left chest cavity. The tumor was resected with a single-sitting 2-stage posterior technique: a microsurgical approach, followed by endoscopic resection via a thoracoscopic approach. There are several reports in the literature on the combined approach for dumbbell tumors of the spinal cord. Our case is the first to describe 2-stage combined surgery in 1 sitting for dumbbell hemangioma with the patient in the lateral decubitus position for the thoracoscopic part of the surgery; and the use of a fat pad, which was applied in the neuroforamen via the posterior route, as a marker for resection during the transthoracic procedure.

Microsurgical Resection of Spinal Cord Hemangioblastoma: 2-Dimensional Operative Video

This video demonstrates microsurgical resection of spinal cord hemangioblastoma. Hemangioblastomas are rare, benign, highly vascularized tumors classified as grade I according to World Health Organization classification systems. About 3% of all intramedullary tumors are hemangioblastomas.1,2 Spinal cord hemangioblastomas are either sporadic3,4 or manifestations of von Hippel-Lindau (VHL) disease in 20% to 45% of patients.5,6 A 30-year-old male presented with sudden onset urinary incontinence. Magnetic resonance imaging showed contrast enhancing intramedullary tumor with adjacent cyst in T11, and syringomyelia extending to C1. Surgical resection followed rules that apply to resection of arteriovascular malformations: coagulation of arterial feeders precedes the coagulation of the draining vein, which is preserved until the end of surgery.2,4,5,7,8 First, posterior midline myelotomy was performed and the tumor cyst was drained in order to develop a dissection plane. Following this, we continuously separated dorsal nerve roots from the tumor nodule using microsurgical technique. The key step in tumor resection is devascularization of the tumor, achievable in 2 ways.2,7,9-13 The circumferential detachment of the normal pia from the tumor pia is crucial in developing a plane of dissection. The coagulation and division of arterial feeders while preserving the drainage vein further devascularizes the tumor. Once the tumor mural nodule was detached from the spinal cord, the drainage vein was coagulated last and the tumor was removed. The patient fully recovered from his incontinence and was neurologically intact. Screening for VHL disease was negative. Written consent was obtained directly from the patient.