Spinal arachnoid cysts in adults: diagnosis and management. A single-center experience

Abstract

<jats:sec><jats:title>OBJECTIVE</jats:title><jats:p>Adult spinal arachnoid cysts (SACs) are rare entities of indistinct etiology that present with pain or myelopathy. Diagnosis is made on imaging studies with varying degrees of specificity. In symptomatic cases, the standard treatment involves surgical exploration and relief of neural tissue compression. The aim of this study was to illustrate features of SACs in adults, surgical management, and outcomes.</jats:p></jats:sec><jats:sec><jats:title>METHODS</jats:title><jats:p>The authors searched medical records for all SACs in adults in the 10-year period ending in December 2016. Radiology and pathology reports were reviewed to exclude other spine cystic disorders. Recurrent or previously treated patients were excluded. Demographic variables (age, sex) and clinical presentation (symptoms, duration, history of infection or trauma, and examination findings) were extracted. Radiological features were collected from radiology reports and direct interpretation of imaging studies. Operative reports and media were reviewed to accurately describe the surgical technique. Finally, patient-reported outcomes were collected at every clinic visit using the SF-36.</jats:p></jats:sec><jats:sec><jats:title>RESULTS</jats:title><jats:p>The authors’ search identified 22 patients with SACs (mean age at presentation 53.5 years). Seventeen patients were women, representing an almost 3:1 sex distribution. Symptoms comprised back pain (n = 16, 73%), weakness (n = 10, 45%), gait ataxia (n = 11, 50%), and sphincter dysfunction (n = 4, 18%). The mean duration of symptoms was 15 months. Seven patients (32%) exhibited signs of myelopathy. All patients underwent preoperative MRI; in addition, 6 underwent CT myelography. SACs were located in the thoracic spine (n = 17, 77%), and less commonly in the lumbar spine (n = 3, 14%) and cervical/cervicothoracolumbar region (n = 2, 9%). Based on imaging findings, the cysts were interpreted as intradural SACs (n = 11, 50%), extradural SACs (n = 6, 27%), or ventral spinal cord herniation (n = 2, 9%); findings in 3 patients (14%) were inconclusive. Nineteen patients underwent surgical treatment consisting of laminoplasty in addition to cyst resection (n = 13, 68%), ligation of the connecting pedicle (n = 4, 21%), or fenestration/marsupialization (n = 2, 11%). Postoperatively, patients were followed up for an average of 8.2 months (range 2–30 months). Postoperative MRI showed complete resolution of the SAC in 14 of 16 patients. Patient-reported outcomes showed improvement in SF-36 parameters. One patient suffered a delayed wound infection.</jats:p></jats:sec><jats:sec><jats:title>CONCLUSIONS</jats:title><jats:p>In symptomatic patients with imaging findings suggestive of spinal arachnoid cyst, surgical exploration and complete resection is the treatment of choice. Treatment is usually well tolerated, carries low risks, and provides the best chances for optimal recovery.</jats:p></jats:sec>

Rare dorsal thoracic arachnoid web mimics spinal cord herniation on imaging

“…Also, a dorsal indentation of cord (e.g., the "scalpel sign") and/ or an abnormal lesion on T-2 axial images in the dorsal subarachnoid space. [1][2][3]6] Further supporting, the diagnosis of DAW is CSF flow quantitative study using a cardiacgated phase-contrast cine-mode that can show a marked reduction in rostral CSF flow in the dorsal subarachnoid space. [1] Alternatively, the diagnosis of VSCH would be better confirmed by an MR or myelo-CT documenting a segment of cord parenchyma extending outside the dura mater, while for SAC, there would be no such pathognomonic MR signs.…”

“…For DAW, there are no pathognomonic signs on CT myelogram. [1][2][3][4][5][6][7] Alternatively, with VSCH, the CT myelogram shows herniation of the cord through a dural defect with no contrast seen anterior to the cord itself while for SAC; the flow of contrast on a myelo-CT study is interrupted by a space-occupying lesion in the dorsal subarachnoid space. [1,7]…”

Intradural Thoracic Arachnoid Cyst Fenestration for Spinal Cord Compression: A Case Illustration and Video Demonstration

“…We describe a case of progressive back pain, lower extremity weakness and incontinence caused by a long segment dorsal arachnoid cyst of the thoracic spine. Traditionally, the surgical approach will entail one long incision spanning the T4-T10 spinal segments in other to gain access to the entire lesion [3]. This will require a large incision, resulting in more blood loss intraoperatively with a large area of wound exposed to potential infections.…”

“…Spinal arachnoid cysts are usually diagnosed either as an incidental finding or in patients with a long history of back pain with or without myelopathy who finally undergo neuroimaging [2]. On magnetic resonance imaging (MRI), they are usually dorsal lesions with an intensity that is similar to cerebrospinal fluid (CSF) [3]. It occurs most commonly in the thoracic spine, followed by the cervical spine and least in the lumbar spine [4].…”

Microsurgical excision of a compressive thoracic arachnoid cyst: Technical pearls

“…The key clinical message of this case is that it is critical to differentiate between arachnoid cysts (Figure ) and spinal cord herniation. This is performed by evaluating the ventral dura to assure that it remains intact …”