Spinal extradural arachnoid cysts: a rare entity and review of the literature.

OBJECTIVE: Spinal extradural arachnoid cysts (SEDC) are rare primary spinal lesions, accounting for less than 1% of all spinal epidural lesions. The literature contains only case reports of this pathology, and treatment remains controversial due to its rarity. Major reported SEDC cases are caused by leaking out of cerebrospinal fluid through a dural defect in the thecal sac forming an extradural cyst. Other reports describe non-communicating SEDC cases where the dural defect was not identified. We report a literature review on SEDC and the case of a 53 year­old female who presented with type IA extradural cyst with subarachnoid space communication. METHODS: Literature review, preoperative imaging and surgical technique. RESULTS: The extradural cyst was excised completely and the dural defect was repaired. After surgical decompression, neurological symptoms gradually recovered. CONCLUSIONS: The extradural arachnoid cyst is an uncommon entity. Preoperative imaging is one of the determining elements in orienting the therapeutic management of the SEDCs. The choice of the surgical technique must be the least invasive in order to avoid postoperative complications. Subtotal or complete excision of the cyst, followed by obliteration of the communication stalk and repair of the dural defect is the gold standard treatment.

Cysts associated with intramedullary ependymomas of the spinal cord: clinical, MRI and oncological features.

PURPOSE: Few published articles have explicitly focused on cysts associated with intramedullary (IM) ependymomas. The objective was to assess the clinical, MRI, and oncological results of patients operated for an IM ependymoma associated with a cystic portion. METHODS: During the study period, 23 IM tumors resected were cystic ependymomas. The modified McCormick scale was used to assess the neurological function of patients. The diagnosis of cystic spinal cord tumor was made on preoperative MRI. RESULTS: Two types of cysts were identified according to their location: either intra-tumoral cysts (ITC) or satellite cysts (SC). ITC (52.2%) were more frequent than SC (21.7%), but 26.1% of patients presented both. ITC were enhanced by gadolinium while SC were not. The solid portion of ependymomas with ITC was significantly larger than the one of ependymomas with SC (p = 0.002). The mean time to the first occurrence of symptoms was significantly shorter in patients with neurological deficit than those without a deficit (p = 0.04). GTR was achieved in 78.2% of cases. Complete excision of the cysts was easier when they were larger (p = 0.006). Sixty percent of cysts disappear postoperatively. Persistence of satellite cysts despite GTR of the tumor, and with no recurrence of a tumor on the post-operative MRI, was observed for 3 patients. CONCLUSION: ITC and SC are different in location, volume, gadolinium enhancement. Their surgical management is different since ITC are resected while SC are drained. Cystic recurrence and/or persistence are not synonymous with tumor recurrence.

Transdural Spinal Cord Herniation: An Exceptional Complication of Thoracoscopic Discectomy: 2-Dimensional Operative Video.

Thoracic disc herniation is a rare and severe condition, whose treatment may have complications including dural tears. Although benign in most cases, dural tears may induce iatrogenic transdural herniation of the spinal cord. The video demonstrates the diagnosis and surgical treatment of iatrogenic transdural herniation of the spinal cord. Here, we report a case of spinal cord herniation after thorascopic treatment of a thoracic disc herniation (DH). A 28-yr-old male presented with several years of left lower extremity weakness and was found to have a T6-7 DH. He underwent DH resection through video assisted mini-thoracotomy at another institution. In the immediate postoperative period, he developed a Brown-Sequard syndrome with left leg weakness. The surgeon decided not to reoperate and the patient improved with rehabilitation, allowing him to walk again. At 6 mo postop, he experienced sudden neurologic worsening but did not present to our clinic until 6 mo later. At this time, he had near complete paraplegia with bilateral lower extremity spasticity and central neuropathic pain. MRI showed a pseudo-meningocele and features suggesting a lateral spinal cord herniation. After a multidisciplinary meeting, we elected to perform a posterolateral approach with costo-arthro-pediculectomy and durotomy to repair the SC herniation. Immediately postop, the patient had a slight improvement in right lower extremity function, with decreased pain and spasticity. This case shows a transdural SC herniation, a rare complication after resection of DH. It is possible that an unreported or unrecognized dural tear at the time of the initial surgery, combined with the negative pressure of the thoracic cavity, put the patient at risk for this particular complication. The authors state that the patient gave his informed consent.

A rare, high cervical traumatic spinal subdural hematoma.

Spinal subdural hematomas (SSDH) are rare lesions occurring in association with a wide variety of conditions, including anticoagulation, coagulation disorders, spinal anesthesia, lumbar puncture, spinal tumors and vascular malformations. SSDH resulting from trauma are the exception. We present a 62-year-old woman with a rare post-traumatic focal SSDH at C1 with bulbomedullary compression, treated successfully with surgery. A review of the literature revealed 26 patients with traumatic SSDH. The aim of this report is to describe the clinical presentation, imaging characteristics and management of traumatic SSDH. The controversial pathogenesis is also discussed.