Lumbar discal cysts: a systematic literature review of diagnostic features and treatment strategies

Purpose: Discal cysts are epidural masses connected to the intervertebral disk, primarily affecting younger individuals. Distinguishing discal cysts from other cystic masses within the epidural space is challenging due to overlapping clinical symptoms and neuroimaging characteristics. This systematic review aims to analyze the diagnostic features and management strategies of lumbar discal cysts. Methods: A comprehensive literature search was conducted following PRISMA guidelines. Relevant studies published between January 1990 and July 2023 were included. Data on diagnostic features, management strategies, and outcomes were extracted. The quality of included studies was assessed using the Newcastle–Ottawa Scale. Results: This systematic review examined a total of 52 articles and 118 cases of discal cysts, including one institutional case. The median age of the patients was 30 years, with a higher prevalence of males. The median follow-up period was 12 months. The most common symptoms reported were leg pain (87.3%) and low back pain (71.2%). Physical examination findings were positive in 45.5% of patients, including hypoesthesia (23.2%), leg weakness (18.8%), and positive straight leg raise test (19.6%). All patients underwent spinal lumbar MRI, which revealed discal nodularity that appeared hypointense in T1-weighted sequences with cystic wall enhancement and hyperintense in T2-weighted sequences. Contrast-enhanced MRI showed enhancement of the cyst wall in the cases where it was performed. Discal cysts were mainly at the L4–L5 level (44.9%) and L5-S1 level (26.3%), with a ventrolateral (94.9%), ventral (4.2%), or lateral position (0.8%). Various treatment modalities were used, including conservative management (5.9%), microscopic cyst resection and discectomy (32.2%), microscopic cyst resection (28.8%), microendoscopic cyst resection (22.1%), and CT-guided cyst aspiration (11%). The majority of patients experienced progressive improvement of symptoms. Conclusion: Discal cysts generally present with low back and radicular pain and can be diagnosed using MRI. Differential diagnoses must be considered to ensure accurate diagnosis and appropriate management. Conservative treatment is typically the initial approach, while surgical interventions are considered for refractory cases.