Tarlov Cyst Mimicking Large Symptomatic Ovarian Cyst: A Case Report

Introduction: Tarlov cyst are usually formed between endoneurium and perineurium, and their lining contain nerve fibers or ganglion cells.Large symptomatic cysts are considered rare. This case is reported due to its unique presentation in which the Tarlov cyst presented in a pregnant patient and was asymptomatic despite its large size. Case: A 28 year old primigravida was suspected to have an ovarian cyst after a baseline antenatal early ultrasound scan She was managed conservatively as she was asymptomatic. She started to have lower abdominal pain at 17 weeks of POA.The gynaecologist advised for laparotomy and cystectomy.Intra operatively the cyst appeared to arise from retroperitoneal space. Diagnostic aspiration was done.MRI done post operatively that showed a huge cystic lesion, measuring 8.3 cm x 9.1cm x 10cm and associated with another lobulated multiseptated cystic lesion in the spinal canal at L5 vertebra and sacrum. Patient remained asymptomatic and was planned for elective C section with a repeat MRI post delivery.Discussion: The common symptoms are pain in the lower back, coccyx, lower extremities or groin. Other symptoms can be hypesthesia or paresthesia over buttocks, between legs and lower body with bladder incontinence with lower body weakness and impotence.Giant Tarlov cyst is when the diameter is more than 3cm and it is exceedingly rare with about only 10 cases reported so far.The best way to assess and diagnose Tarlov cyst is by MRI. It has the highest diagnostic value because there will be no bony interference and enhanced resolution of tissue density. Management can be surgical or non surgical.Conclusion: Tarlov cyst is a rare occurrence and can be symptomatic if the size is large. Surgical treatment will resolve symptoms with low rate of recurrence. There are many surgical treatments available however non is proven superior to the other. Despite its rare nature, Tarlov cyst should be considered and diagnosed promptly.