Bead-like schwannomas at the cauda equina are rare but benign intraspinal tumors. They can involve multiple nerve roots and spread within the spinal canal, and open resection would cause significant trauma. The authors have successfully applied a novel minimally invasive technique for the total removal of such schwannomas. A 68-year-old woman presented with a 1-month history of left waist and leg pain. MRI demonstrated multiple intraspinal lesions located from L1 to S1. The diagnosis was bead-like schwannomas at the cauda equina. Two incisions were made at the T12 and L5 levels. A flexible endoscope was introduced into the spinal canal following hemisemilaminectomy under a microscope to identify the relationship between the tumors and the carrying nerves. After dissecting both cranial and caudal ends of the carrying nerve, the string of bead-like tumors was gently pulled out from the caudal end as a whole. The endoscope was reintroduced into the spinal canal to ensure complete tumor removal. The patient recovered quickly, and no tumor residual was found at postoperative MRI. Flexible endoscope–assisted visualization plus microscopic hemisemilaminectomy via 2 incisions is a feasible minimally invasive approach for selected patients with bead-like schwannomas at the cauda equina.
Yu-Cheng Ren, Bin-Jie Zhao, Zhi-Yi Xie, Guang-Yu Ying, Fang Shen, and Yong-Jian Zhu
Yong-Jian Zhu, Guang-Yu Ying, Ai-Qin Chen, Lin-Lin Wang, Dan-Feng Yu, Liang-Liang Zhu, Yu-Cheng Ren, Chen Wang, Peng-Cheng Wu, Ying Yao, Fang Shen, and Jian-Min Zhang
Posterior midline laminectomy or hemilaminectomy has been successfully applied as the standard microsurgical technique for the treatment of spinal intradural pathologies. However, the associated risks of postoperative spinal instability increase the need for subsequent fusion surgery to prevent potential long-term spinal deformity. Continuous efforts have been made to minimize injuries to the surrounding tissue resulting from surgical manipulations. The authors report here their experiences with a novel minimally invasive surgical approach, namely the interlaminar approach, for the treatment of lumbar intraspinal tumors.
A retrospective review was conducted of patients at the Second Affiliated Hospital of Zhejiang University School of Medicine who underwent minimally invasive resection of lumbar intradural-extramedullary tumors. By using an operative microscope, in addition to an endoscope when necessary, the authors were able to treat all patients with a unilateral, paramedian, bone-sparing interlaminar technique. Data including preoperative neurological status, tumor location, size, pathological diagnosis, extension of resections, intraoperative blood loss, length of hospital stay, and clinical outcomes were obtained through clinical and radiological examinations.
Eighteen patients diagnosed with lumbar intradural-extramedullary tumors were treated from October 2013 to March 2015 by this interlaminar technique. A microscope was used in 15 cases, and the remaining 3 cases were treated using a microscope as well as an endoscope. There were 14 schwannomas, 2 ependymomas, 1 epidermoid cyst, and 1 enterogenous cyst. Postoperative radiological follow-up revealed complete removal of all the lesions and no signs of bone defects in the lamina. At clinical follow-up, 14 of the 18 patients had less pain, and patients' motor/sensory functions improved or remained normal in all cases except 1.
When meeting certain selection criteria, intradural-extramedullary lumbar tumors, especially schwannomas, can be completely and safely resected through a less-invasive interlaminar approach using a microscope, or a microscope in addition to an endoscope when necessary. This approach was advantageous because it caused even less bone destruction, resulting in better postoperative spinal stability, no need for facetectomy and fusion, and quicker functional recovery for the patients. Individualized surgical planning according to preoperative radiological findings is key to a successful microsurgical resection of these lesions through the interlaminar space.
Chen Wang, Chien-Min Chen, Fang Shen, Xiao-Dong Fang, Guang-Yu Ying, Yu-Cheng Ren, Dan-Feng Yu, Liang-Liang Zhu, Yong-Jian Zhu, and Jian-Min Zhang
Spinal dural arteriovenous fistulas (SDAVFs) are the most common type of spinal arteriovenous malformations, and microsurgical ligation is the treatment modality most frequently used for these lesions. Developments in endoscopic techniques have made endoscopy an even less invasive alternative to routine microsurgical approaches in spine surgery, but endoscopic management of SDAVF or other intradural spinal lesions has not been reported to date.
The authors describe the use of a microscope-assisted endoscopic interlaminar approach for the ligation of the proximal draining vein of an L-1 SDAVF in a 58-year-old man. A complete cure was confirmed by postoperative angiography. The postoperative course was uneventful, and short-term follow-up showed improvements in the patient's neurological function. The authors conclude that the endoscopic interlaminar approach with microscope assistance is a safe, minimally invasive, innovative technique for the surgical management of SDAVFs in selected patients.
Xiao-hui Ren, Chun Chu, Chun Zeng, Yong-ji Tian, Zhen-yu Ma, Kai Tang, Lan-bing Yu, Xiang-li Cui, Zhong-cheng Wang, and Song Lin
Intracranial epidermoid cysts are rare, potentially curable, benign lesions that are sometimes associated with severe postoperative complications, including hemorrhage. Delayed hemorrhage, defined as one that occurred after an initial unremarkable postoperative CT scan, contributed to most cases of postoperative hemorrhage in patients with epidermoid cyst. In this study, the authors focus on delayed hemorrhage as one of the severe postoperative complications in epidermoid cyst, report its incidence and its clinical features, and analyze related clinical parameters.
There were 428 cases of intracranial epidermoid cysts that were surgically treated between 2002 and 2008 in Beijing Tiantan Hospital, and these were retrospectively reviewed. Among them, the cases with delayed postoperative hemorrhage were chosen for analysis. Clinical parameters were recorded, including the patient's age and sex, the chief surgeon's experience in neurosurgery, the year in which the operation was performed, tumor size, adhesion to neurovascular structures, and degree of resection. These parameters were compared in patients with and without delayed postoperative hemorrhage to identify risk factors associated with this entity.
The incidences of postoperative hemorrhage and delayed postoperative hemorrhage in patients with epidermoid cyst were 5.61% (24 of 428) and 4.91% (21 of 428), respectively, both of which were significantly higher than that of postoperative hemorrhage in all concurrently treated intracranial tumors, which was 0.91% (122 of 13,479). The onset of delayed postoperative hemorrhage ranged from the 5th to 23rd day after the operation; the median time of onset was the 8th day. The onset manifestation included signs of intracranial hypertension and/or meningeal irritation (71.4%), brain herniation (14.3%), seizures (9.5%), and syncope (4.8%). Neuroimages revealed hematoma in 11 cases and subarachnoid hemorrhage in 10 cases. The rehemorrhage rate was 38.1% (8 of 21). The mortality rate for delayed postoperative hemorrhage was 28.6% (6 of 21). None of the clinical parameters was correlated with delayed postoperative hemorrhage (p > 0.05), despite a relatively lower p value for adhesion to neurovascular structures (p = 0.096).
Delayed postoperative hemorrhage contributed to most of the postoperative hemorrhages in patients with intracranial epidermoid cysts and was a unique postoperative complication with unfavorable outcomes. Adhesion to neurovascular structures was possibly related to delayed postoperative hemorrhage (p = 0.096).