Intradural Tumors Research Articles

MANAGEMENT OF EXTRAMEDULLARY INTRADURAL SPINAL TUMORS

Spinal tumors are relatively uncommon, accounting for approximately 5%–10% of all central nervous system tumors, with an estimated 70%–80% being located in the intradural extramedullary space. The most common intradural extramedullary tumors are schwannomas, followed by meningiomas. Other less common intradural extramedullary tumors include myxopapillary ependymomas. The clinical presentation of these tumors is often rather nonspecific, and clinicians must maintain a high index of suspicion when evaluating patients with chronic back pain. Approximately 50% of affected individuals experience nonspecific back pain, whereas radiating pain, motor deficits, and sensory loss often progress gradually. This study examines the surgical management of intradural spinal tumors treated in our department, focusing on surgical techniques Some of these benign lesions can pose a surgical challenge due to their location to spinal cord, tumor consistency (densely mineralized / calcified). Posterior approaches involving laminectomy while preserving facet joints are typically sufficient for the surgical resection of dorsal and dorsolateral tumors. In conclusion the total surgical removal of these tumors while preserving neurological function remains can pose a surgical challenge especially for those that are densely calcifed and situated anterolateral to spinal cord, but employing standard microsurgical techniques often makes these resections possible.

Update on the management of extradural primary pediatric spinal tumors

Osseous/extradural pediatric spine tumors are uncommon and divided into benign and malignant. The Enneking classification is used to divide the benign tumors into latent, benign aggressive and aggressive. The malignant spine tumors include osteosarcoma, Ewing's sarcoma and lymphoma. A tissue biopsy is crucial for diagnosis and is essential to manage these tumors in a multi-disciplinary manner.

Analysis of 398 cases of intradural spinal tumor resection with primary dural closure: surgical outcomes based on the suture material.

Cerebrospinal fluid (CSF) leak after resection of intradural spinal tumors (IST) represents a significant postoperative challenge. Although various dura suture techniques and materials have been explored experimentally, direct clinical comparative studies are lacking. This study evaluated the effectiveness of specific suture materials in primary dural closure post-IST resection and identified associated risk factors for CSF leak. A retrospective review was conducted of patients who underwent IST resection surgery at a single institution from January 2012 to February 2021. Patients were categorized on the basis of the dura suture materials used. Eligibility for the study required a posterior midline surgical approach, primary dural closure after durotomy, and absence of closed-suction drainage. Of 398 patients who met the inclusion criteria, the overall CSF leak-related surgical complication rate was 4.27% (17/398). The sutures used were 6-0 Prolene for 163 patients and 5-0 silk for 235 patients. Significant differences were observed between the suture groups in the CSF leak rate (Prolene 1.8% vs silk 6.0%, p = 0.046), lumbar drainage insertion rate (Prolene 0.6% vs silk 4.3%, p = 0.031), and length of postoperative bed rest (Prolene 1.07 days vs silk 3.25 days, p < 0.001). Logistic regression analysis indicated a significant association of CSF leak with the use of 5-0 silk (OR 4.11, p = 0.006) and revision surgical procedures (OR 6.73, p = 0.001). Surgical complications related to CSF leaks were significantly lower with the use of 6-0 Prolene sutures compared to 5-0 silk sutures in primary dural closure after IST resection.

Lumbar Spinal Meningioma- A common tumor in an uncommon location: A case report

Meningioma in the spinal canal commonly appears as intradural extramedullary spinal tumors at the dorsal and cervical region but is rare in the lumbar area. A 36-year-old man presented to us with complaints of left sciatica, weakness, and difficulty in movements of his left toes for a couple of months. Magnetic Resonance Imaging revealed an enhancing oval-shaped lesion at the level of L4, and histopathology revealed a meningioma. The complete removal has been done with hemilaminectomy for this common tumor in an uncommon location. J Shaheed Suhrawardy Med Coll 2023; 15(1): 78-82

Unilateral Hemilaminectomy as Primary Treatment for Spinal Cord Tumors: Retrospective Cohort of 38 Cases with a Minimum Follow-Up of 24 Months

To evaluate the efficacy of hemilaminectomy as an approach to intradural tumors and to assess the risk of postoperative spinal instability. This is a retrospective cohort study of 38 patients who underwent surgical resection of intradural tumors between November 2014 and March 2019. Clinical and radiological data were documented in medical records, from which we obtained clinical data including age, gender, tumor etiology, lesion level, type of resection, and postoperative instability during follow-up. Schwannomas and meningiomas were the most commonly treated tumors. The lesion locations were as follows: 8 cervical (21%), 19 thoracic (50%), 10 lumbar (26%), and 1 sacral (3%). The mean follow-up time was 28 months. In all cases, hemilaminectomy allowed for the removal of the tumors without clinical or radiologic evidence of postoperative mechanical instability. Hemilaminectomy was primarily performed on 2 segments but was extended to up to 6 levels in some cases. Unilateral hemilaminectomy is an effective technique that facilitates complete tumor removal with a low rate of postoperative instability in the operated segments.

Surgical Outcome of Tumors of Spinal cord, Nerve roots, Meninges, and Vertebral column – Our Experience in Tertiary level Hospital

Background: Spinal cord tumors can result in dramatic neurological and functional disabilities in the patients. We aimed to know the different types of spinal tumors and the correlation between clinical presentation and pathological findings and compare the outcomes of these tumors postoperatively. Methods: A total of 410 patients were included in the retrospective study group. The duration of the study was January 2016 to October 2022 (82 months). After a thorough clinical evaluation, patients were subjected to magnetic resonance imaging (MRI) and then surgery. They were described based on age, sex, location of the tumor, type of the tumor, symptoms, histopathological type, surgical resection, and complications. Results: The study included 229 (56%) males and 181 (44%) females and their ages ranged from 6 years to 74 years. Out of the 410 patients, 203(49.51%) had intradural extramedullary, 121(29.51%) had extradural and 86(20.98%) had intradural intramedullary spinal tumors. A predilection towards the thoracic region (39.50%) and cervical region (28.40%). Lumbar region (20.10%) and Sacral region (4.10%), Cervicodorsal region (1.40%), Dorsolumbar region (3.00%), and Craniovertebral junction (3.50%) were seen. The tumors were excised completely in 72.68% of the patients while neartotal resection was done in 17.82%, subtotal resection in 7.32%, and only biopsy in 2.2% of patients. Histopathologically most of the tumors were Schwannoma (38.78%), then Meningioma (11.71%), Ependymoma (11.70%), Astrocytoma (10.98%), and others were found. There was significant improvement (33.66%) in the modified McCormicks score at discharge follow-up. Conclusions: Intradural extramedullary is the most common spinal cord tumor. The majority of the cases presented with sensorimotor symptoms and pain is the predominant clinical complaint. Spinal cord tumors are most commonly observed in the 2nd to 4th decade of life with a gradual decline in the incidence towards the extremes of age group. Surgery is the definitive treatment and the aim of the surgery is gross total resection Bang. J Neurosurgery 2024; 13(2): 112-120

Spine Stereotactic Radiosurgery Provides Long-Term Local Control and Overall Survival for Benign Intradural Tumors.

The role of radiosurgery in the treatment of benign intracranial tumors is well established. However, there are limited long-term follow-up studies on outcomes after stereotactic radiosurgery (SRS) for benign intradural spinal tumors. In this article, we report a large single-institution experience in using SRS to treat patients with benign intradural tumors of the spine. Overall, 184 patients (55% female) and 207 benign intradural tumors were treated. The median patient age was 52 years (range: 19-93). Tumor histology included schwannoma (38%), meningioma (15%), neurofibroma (21%), hemangioma (9%), hemangioblastoma (8%), hemangiopericytoma (5%), and paraganglioma (4%). Thirty-four (16%) lesions underwent resection before radiosurgery. Twenty-three (11%) lesions were NF1-mutated. The median single-fraction margin dose was 14 Gy (range: 11-20), and the median multifraction margin dose was 21 Gy (range: 15-30). The median follow-up was 63 months (range: 1-258). At last follow-up, tumors volumetrically regressed (15%), remained stable (77%), or locally progressed (8%, median: 20 months [range: 3-161]) after SRS. The 1-, 5-, and 10-year local control rates were 97%, 92%, and 90%, respectively. On multivariable analysis, the absence of the NF1 mutation (P = .004, hazard ratio: 0.23, 95% CI: 0.08-0.63) and single-fraction SRS (P = .007, hazard ratio: 0.24, 95% CI: 0.08-0.68) correlated with improved local control. The median overall survival was 251 months (range: 1-258), and 1-, 5-, and 10-year overall survival rates were 95%, 85%, and 70%, respectively. For patients with pre-existing symptoms, tumor-associated pain and neurological deficits were noted to improve or remain stable in 85% and 87% of cases, respectively. Adverse radiation effects included delayed myelopathy (1%), acute pain flare (9%), dermatitis (0.5%), dysphagia (0.5%), and dysphonia (0.5%). With long-term follow-up, spine radiosurgery is a safe and effective treatment for benign intradural tumors. In carefully selected patients, even with an NF1 mutation, SRS is associated with a high likelihood of local tumor control.

Does the presence or absence of preoperative lower extremity neurologic symptoms influence postoperative clinical outcome in patients with cervical intradural extramedullary tumors?: a single-center retrospective comparative study.

Retrospective comparative study OBJECTIVES: To investigate whether the presence or absence of preoperative lower extremities neurological symptoms (LENS) influences clinical outcomes following tumor resection in patients with cervical intradural extramedullary (IDEM) tumors. The single institution in Japan. Ninety-two patients with cervical IDEM tumors requiring surgical resection were included. Based on the degree of preoperative LENS assessed using the modified McCormick scale (MMCS), patients were categorized into LENS (-) and (+) groups. Demographic and surgical characteristics were compared between both groups. There were no significant differences observed in sex, tumor location, tumor size, surgical time, estimated blood loss, approach for tumorectomy, or tumor histopathology between the two groups. Additionally, the overall surgical outcomes were favorable for both groups. At the final follow-up, 91.1% of the patients in the LENS (+) group were able to walk without support. Improvement in LENS was observed after surgery in most patients with preoperative MMCS II-IV, but it persisted in approximately 40% of patients with preoperative MMCS V. In the LENS (+) group, there were no significant differences in demographic or surgical data between the patients with MMCS I and II-III at the final follow-up. Regardless of the presence or absence of preoperative LENS, clinical improvement was observed after tumor resection in most patients with cervical IDEM tumors. These findings suggest that neurological status is likely to improve sufficiently if tumor resection is performed before preoperative LENS deteriorates to an extremely severe stage as MMCS V.

Management of intradural extramedullary and intramedullary spinal tumors

Intradural spine tumors are relatively uncommon and include tumors outside (extramedullary) or within the spinal cord (intramedullary). The proximity of these tumors to important neural structures can cause significant neurologic morbidity and prompt management is critical for maintaining function. Surgical intervention is generally the primary treatment depending on presenting symptoms, radiologic features, and the likelihood of a clear surgical planes vis-à-vis the spinal cord. Adjuvant radiation, chemotherapy, or other novel therapeutic strategies may play a role in postoperative management. Here we review management strategies for common intradural extramedullary (meningiomas, schwannomas, and neurofibromas) and intradural intramedullary tumors (astrocytomas, ependymomas, and hemangioblastomas).

Endoluminal Sigmoid Sinus Occlusion During Jugular Foramen Tumor Surgery: Novel Technique, Operative Nuances, and Clinical Experience With 33 Patients.

Surgery of jugular foramen tumors (JFTs) often requires vascular control by means of ligating the internal jugular vein and sigmoid sinus (SS) to allow intrabulbar access. Occlusion of the SS traditionally involves presigmoid and retrosigmoid durotomies allowing introduction of ligature devices, predisposing to cerebrospinal fluid (CSF) leakage and pseudomeningoceles. We describe a simple and novel endoluminal sigmoid sinus occlusion (ESSO) technique with Gelfoam that is entirely extradural. An extended anterolateral infralabyrinthine approach with ESSO was performed in 33 patients with JFTs. After ligating the internal jugular vein, the SS is opened and Gelfoam is placed endoluminally into the proximal SS. Care is taken to avoid occlusion of the venous outflow of the vein of Labbe to avoid temporal lobe venous infarction. Hemostatic gelatin matrix is injected distally to stop venous backflow from the inferior petrosal sinus. The jugular venous system is isolated, and the outer jugular wall can be opened to expose the JFT for resection. There were no complications of temporal lobe venous infarction or postoperative hematoma observed. Four patients with intradural tumor extension developed pseudomeningoceles. For patients with purely extradural JFTs, none developed postoperative incisional CSF leaks and one had pseudomeningocele. This ESSO technique is fast and effective, permitting occlusion of the SS during JFT surgery. It has the advantage of being entirely extradural, avoiding durotomy which can result in postoperative CSF leak. It is important to keep the Gelfoam distal to the transverse-sigmoid junction to avoid occlusion of the vein of Labbe inlet and temporal lobe venous infarction.

Transcranial Corticospinal Motor-Evoked Potentials in Cases of Ventral and Ventrolateral Intradural Extramedullary Cervical Spinal Cord Tumors.

Background and Objectives: We studied the clinical significance of an amplitude decrement and disappearance alarm criteria in transcranial motor-evoked potential (MEP) monitoring during surgeries on extramedullary tumors at the cervical spine with reference to postoperative morbidity. Material and Methods: We diagnosed and surgically treated fourteen patients with intradural extramedullary ventral or ventrolateral lesions to the cervical spinal cord in the Clinic of Neurosurgery at the University Hospital St Ivan Rilski from January 2018 to July 2022. Eight cases were diagnosed with schwannoma, and the remaining six had meningiomas. The follow-up period for neurological assessment was six months. Results: A decrease in the intraoperative transcranial MEPs of 50% or more compared to baseline in two cases (14.3%) resulted in an immediate postoperative motor deficit. One patient demonstrated full neurological recovery within six months, while the other exhibited only partial improvement. In six cases (42.9%) with preoperative motor deficits, tumor resection and decompression of the cervical spinal cord led directly to an increment of the transcranial MEPs by more than 20%. Postoperatively and at the 6-month follow-up, these patients showed recovery from the preoperative deficits. In the remaining cases, MEPs were stable during surgery with no clinical deterioration of the motor function. Conclusions: The decremented MEP criteria corresponded to postoperative motor deficit, whereas the improvement of the same parameters after decompression implied future recovery of preoperative motor deficits. The combination of different MEP criteria is likely to be helpful when tailored to a specific case of ventral or ventrolateral extramedullary lesions in the cervical spine.

High-Definition 4K-3D Exoscope in Spine Surgery: A Single-Center Experience and Review of the Literature.

Background and Objectives: Binocular optical microscopy (OM) paved the way for a new era in brain and spine neurosurgery fields with the introduction of microsurgery. Despite its enormous contribution to modern neurosurgery, OM presents some intrinsic limitations that surgeons need to face during procedures such as prolonged non-ergonomic positions and decreased vision quality to the assistant eyepiece. To overcome these limitations, in recent years, new operative tools have been introduced, such as exoscopes. Here, we present our experience with exoscopes in spine surgery. Materials and Methods: In the period between January 2022 and December 2023, we gradually implemented the use of a high-definition 4K-3D exoscope (ORBEYETM, Olympus, Japan) in patients undergoing spinal surgery. Results: A total of 243 patients underwent spine surgery with exoscope magnification (47 intradural tumors, 99 lumbar degenerative cases, 79 cervical degenerative cases, 5 dorsal calcified disk herniations, 4 dural arteriovenous fistulas (dAVFs), and 9 others). We compared this cohort with a similar cohort of patients operated in the same period using OM based on different endpoints: operating time, complication rate, and infection rate. We did not find any statistically significant difference in any of the endpoints between these two groups. Conclusions: In our experience, the exoscope provides a better resolution of spinal anatomy and higher quality real-time images of the surgery for the entire OR team and improves the ergonomic posture of both surgeons, without lengthening the operating time and without increasing the rate of adverse events. Prospective studies with a larger cohort of patients are needed to further validate these findings.

Preoperative definition and new concept design of 3D printed buttress model to seal skull base after endoscopic endonasal surgery

PurposeThis study aims to integrate design methods and additive manufacturing with the use of a thermoplastic elastomer certified for medical use and reverse engineering towards a new concept of a customized buttress model with optimized features for the reconstruction of the osteo-dural opening after endoscopic endonasal transtuberculum-transplanum approach.Design/methodology/approachAdditive manufacturing allows making of cost-effective and useable devices with tailored properties for biomedical applications. The endoscopic endonasal approach to the suprasellar area enables the management of different intradural tumours, and the craniectomy at the skull base is generally wide and irregular. Defining an optimal strategy for osteodural defect closure at the preoperative stage represents a significant challenge.FindingsUsing the results obtained from a computed tomography analysis, skull base defects were designed to plan the surgical approach. Several concepts of customized buttress models were first built up, initially focusing on thin, flexible edges characterized by different thicknesses. Finite element analyses and design optimization allowed us to achieve the optimal design solution with improved compliance/flexibility for easy intranasal manoeuvrability, maintaining an adequate mechanical stability. As the thickness of the edges decreased, an increase of strain energy values was found (i.e. 1.2 mJ – Model A, 1.7 mJ – Model B, 2.3 mJ – Model C, 4.3 mJ – Model D). However, a further optimization (Model E) led to a significant increase of the compliance (strain energy of 14.1 mJ).Originality/valueThe results obtained from clinical evaluations demonstrated the feasibility of the proposed technical solutions, improving surgery effectiveness.

Clinical evaluation of enhanced recovery versus conventional care in the perioperative period for intradural extramedullary spinal tumors: a study protocol for a multicenter, randomized controlled trial

BackgroundThis randomized clinical trial protocol aimed to investigate the comparative efficacy of an enhanced recovery after surgery (ERAS) protocol versus traditional perioperative care programs in patients with intradural extramedullary spinal tumors.MethodsThe study included 180 patients aged 18–80 years, who were randomly assigned to two groups: Group A receiving traditional perioperative care and Group B receiving accelerated rehabilitation perioperative care. The nurse responsible for patient care was informed of the group assignment, but the patients themselves remained blinded to the intervention. The primary outcome measure was the Karnofsky Performance Scale score, which assessed functional status. The secondary outcomes included the Japanese Orthopedic Association Scale, Numeric Pain Rating Scale, length of postoperative hospital stay, duration of urethral catheterization, patient satisfaction questionnaire, and complication rates. Follow-up assessments were conducted telephonically 1 month, 3 months, and 6 months after the surgery.DiscussionThis study protocol provided a structured approach to assess the potential benefits of ERAS during the perioperative period for patients with intradural extramedullary tumors, aiming to improve patient outcomes and overall care efficiency.Trial registrationThis study has been registered with the China Clinical Trials Registry (Project No: ChiCTR2200063347). Registered on September 5 2022.

Minimally Destabilizing Corridor for Resection of Dumbbell Nerve Sheath Tumors: A Novel Surgical Technique.

Current surgical strategies for dumbbell nerve sheath tumors (DNSTs) with cord compression have primarily involved wide spinal exposures with total laminectomy and unilateral facetectomy, often leading to spinal destabilization and requiring fusion, or staged procedures separately addressing the intraspinal and extraforaminal tumor components. This study highlights technical nuances of a novel approach for DNST resection to minimize spinal destabilization and avoid fusion while facilitating safe, single-stage complete resection. A retrospective chart review was conducted on patients undergoing DNST resection. Using unilateral subperiosteal dissection, hemilaminotomy and medial facetectomy procedures are performed. The extradural tumor component is resected, followed by internal decompression of the intradural tumor. A small horizontal incision at the origin of the nerve root sleeve releases the underlying dural stricture, facilitating delivery of the remaining intradural tumor and allowing section of the nerve root of origin. Ultrasonography confirms complete tumor resection and return of cord pulsation, and excludes intradural hemorrhagic complications. The dura is reconstructed using a dural substitute bolstered with fat graft and sealant. Twelve consecutive patients undergoing this approach from 2014 to 2021 were included. Mean patient age was 53.5 years, and 58.3% were male. Nine tumors were cervical and 3 were lumbar. Five patients presented with myelopathy, 4 with radiculopathy, and 4 with axial pain. Two cases had transient intraoperative neuromonitoring signal changes. Eleven tumors were diagnosed as schwannomas and 1 as neurofibroma. All patients had complete resection of the intraspinal component; 2 had far distal extraforaminal residual. No patient has had recurrence, progression of residual, or signs of spinal instability during follow-up (median 28.5 months, range 6-66 months). This study highlights technical considerations for DNST resection, focusing the approach at the center of the tumor, with minimal bone removal and ligamentous disruption. Intraoperative ultrasound is instrumental in the safety of this approach.

Epidemiological features of spinal intradural tumors, a single-center clinical study in Beijing, China

BackgroundSpinal intradural tumors are rare and heterogeneous in histological type, aggressiveness, and symptomatology, and there is a lack of data about them. This study investigated the epidemiological features of spinal intradural tumors.MethodsThis retrospective analysis included patients with spinal intradural tumors who underwent surgical treatment at the Myelopathy and Spondylosis Ward Beijing Jishuitan Hospital between January 2012 and December 2022.ResultsThis study included 1321 patients [aged 47.19 ± 14.90 years, 603 (45.65%) males] with spinal intradural tumors. The most common histological subtype was schwannoma [n = 511 (38.68%)], followed by spinal meningioma [n = 184 (13.93%)] and ependymoma [n = 101 (7.65%)]. Fifteen (1.14%) patients were diagnosed with metastatic spinal intradural tumors as a presentation of another primary cancer type. The spinal intradural tumors were mostly found in the lumbar region [n = 436 (33.01%)], followed by the thoracic vertebrae [n = 390 (29.52%)], cervical vertebrae [n = 154 (11.66%)], and thoracolumbar region [n = 111 (8.40%)]. Schwannomas mostly affected the lumbar region [n = 256 (52.64%)], spinal meningiomas in the thoracic region [n = 153 (83.15)], and ependymomas in the lumbar region [56 (55.45%)]. The de novo metastases were mostly found in the lumbar region [n = 8 (53.33%)].ConclusionAccording to the results of our single-center study, the most common spinal intradural tumor in Northern China is schwannoma, followed by spinal meningioma and ependymoma.

A Concise Guide to D-Wave Monitoring during Intramedullary Spinal Cord Tumour Surgery.

D-waves (also called direct waves) result from the direct activation of fast-conducting, thickly myelinated corticospinal tract (CST) fibres after a single electrical stimulus. During intraoperative neurophysiological monitoring, D-waves are used to assess the long-term motor outcomes of patients undergoing surgery for intramedullary spinal cord tumours, selected cases of intradural extramedullary tumours and surgery for syringomyelia. In the present manuscript, we discuss D-wave monitoring and its role as a tool for monitoring the CST during spinal cord surgery. We describe the neurophysiological background and provide some recommendations for recording and stimulation, as well as possible future perspectives. Further, we introduce the concept of anti D-wave and present an illustrative case with successful recordings.

Resection and postoperative pazopanib for intraspinal recurrent solitary fibrous tumor: illustrative case.

Intracranial solitary fibrous tumors (SFTs) rarely recur in the spinal space. Only 4 cases of spinal recurrence from intracranial SFT have been reported; therefore, the optimal treatment of recurrent spinal SFT remains unclear. A 53-year-old woman with a history of resection of a right occipital anaplastic SFT presented with progressive back and side pain. She was diagnosed with an intradural extramedullary tumor ventral to the spinal cord at the T5-7 level. She underwent tumor resection with T5-6 laminectomy and T4 and T7 partial laminectomy. The tumor was completely removed in a piecemeal fashion using an ultrasonic aspirator with careful control of bleeding. Her symptoms quickly improved after the surgery, and she returned to normal life. The tumor was diagnosed as SFT. Pazopanib was administered postoperatively. Despite the recurrence of the intracranial tumor, the patient was alive without recurrence of the spinal tumor 14 months after resection. Although rare, intracranial SFTs have a risk of spinal recurrence. Complete resection of a recurrent spinal SFT can be achieved even in the ventral location. Pazopanib could be a possible therapeutic option for preventing local tumor recurrence in the management of recurrent spinal SFT. https://thejns.org/doi/10.3171/CASE24217.

Functional outcome after introduction of hemilaminectomy in management of spinal schwannomas and meningiomas

BackgroundSchwannomas and meningiomas are intradural extramedullary spinal tumors which are regularly encountered in the neurosurgical clinic. These tumors cause neurological deficit by compression on the spinal cord and commonly pain when affecting the cauda equina. The traditional treatment with standard laminectomy (SL) can cause instability to the dorsal segments of the spinal column, and the less invasive option of hemilaminectomy (HL) has therefore been developed. We aim in this study to investigate transition from SL to HL in a population-based cohort. MethodsAdult patients (18 years and older) undergoing primary surgery due to spinal meningioma or schwannoma between 2007 and 2022 at the neurosurgical clinic were included. Data related to clinical, surgical and outcome variables were retrospectively collected. ResultsA total of 187 patients were identified: 155 in the SL group, 26 in the HL group and in 6 patients a combination of SL and HL. The mean age of the SL group was 62.7 years (SD14.2) compared to 58.0 (SD15.7) in the HL group (p = 0.16). Preoperative motor deficit was more common in SL group compared to HL group (76.8 % and 61.5 %, respectively, p = 0.14). Thoracal location was most common for both groups (SL 65.8 % and HL 61.5 %). Postoperative change in McCormick grades and early complications were similar between groups. ConclusionOutcome after hemilaminectomy due to intradural extramedullary schwannoma or meningioma is comparable to standard laminectomy with regards to postoperative complications and neurological improvement. Our findings support the transition to hemilaminectomy in selected cases.

Intradural Melanotic Schwannoma of the Sacral Spine: An Illustrated Case Report of Diagnostic Conundrum

Schwannomas are benign and slow-growing peripheral nerve sheath neoplasms of Schwann cells. These are generally encountered in the neck, head, and flexor areas of the extremities. Even though many schwannomas are easily diagnosable, their variable morphology can occasionally create difficulty in diagnosis. In this study, we present a rare case of melanotic schwannoma of the sacrum, emphasizing the need for routine biopsy to understand the etiology. A 46-year-old man presented to the Department of Neurosurgery, Taipei Medical University Hospital, with buttock pain in the sacrum area for 1 year, which worsened in the last 1–2 months. The patient had no known history of trauma or malignancy. We evidenced an intradural extramedullary neurogenic tumor at the caudal end from S1 to S3. Histologic analysis revealed melanin deposition in the tumor cells. Round to oval tumor cells were positive for HMB-45 and S-100 proteins, suggestive of melanotic Schwannoma, which were removed by laminectomy. After 1 month, the tumor recurred and was further removed surgically. Conclusively, we observed the sacrum as an unusual anatomic site for the possible occurrence of melanotic schwannoma, especially in patients with no known history of trauma and malignancy. The possibility of melanotic schwannoma is very high. We hypothesize that melanotic schwannoma was possible because it occurred in the intradural and extramedullary regions of the spine. Hence, a routine biopsy should be performed to corroborate the exact cause and prevent incorrect presumptions.