gms | German Medical Science

Objective: Spinal arachnoid cysts are rare, mostly idiopathic intradural space-occupying lesions with imminent compression of the spinal cord and clinical signs of radiculo- and/or myelopathy. We retrospectively analyzed the radiological and clinical characteristics of our pat. with surgical treatment of spinal arachnoid cysts including a subgroup with evaluation of long-term outcome and QoL.

Methods: 72 pat. (f:m=1.9:1) with spinal arachnoid cysts treated between 1993 and 2017 were evaluated retrospectively. Craniocaudal (c.c.) and a.p. cyst diameters were measured pre- and post-OP. McCormick and Odom score for myelopathy and general outcome were recorded (mean follow-up 44.8±60 mo). Long-term data were available from 25 pat. (FU 78.2±63.9 mo) with assessment of QoL (SF-36, EORTC-QLQ30).

Results: All pat. had surgery due to solitary cysts: 12 cervical (16.7%), 43 thoracic (59.7%) and 17 lumbosacral (23.6%) - the majority (68.1%) located dorsally. Main symptoms were gait disturbance (80%), dysaesthesia (64%), lower limb paresis (56%) Pat. had (hemi-)laminectomy with cyst fenestration in 48 (66.7%) and complete resection in 18 cases (25.0%). 4 cases (5.5%) were treated by cystoperitoneal shunt and 2 by marsupialization (2.8%). IOM (available in 41% of pat.) showed improved or stable SEPs/MEPs after cyst resection/fenestration in all cases, no deterioration was detected. Re-OP was done in 7/72 (9.7%) pat. for wound revision (n=1), epidural hematoma (n=1) and for additional cyst wall resection (n=5, after 3.0-76.2 mo) due to insufficient shrinking of multiple septated, mostly post-hemorrhagic cysts. The mean c.c. cyst size decreased from 5.2±3.7 cm pre-OP to 2.7±3.9 cm (p<0.05), the a.p. diameter decreased from 1.0±0.5 cm to 0.3±0.3 cm (p<0.0001) without significant differences between pat. with fenestration or resection. McCormick and Odom scores revealed significantly improved symptoms, particularly of gait disturbance, sensory deficits, and general performance. Long-term follow-up displayed satisfying QoL performance without differences of fenestration or resection.

Conclusion: Spinal intradural arachnoid cysts mostly affect women and are predominantly located in the thoracic spine, becoming apparent with clinical myelopathy. After imaging exclusion of multiple intracyst compartments, both fenestration and resection of the cyst wall provided a significant reduction of cyst size and clinical improvement.