Surgical management of a Symptomatic Sacral Tarlov cyst:A case reportPrakash Regmi1, Sandeep Bohara1,Alok C Thakur1, Dipendra K Shrestha1, Gopal Sedain11 Department of Neurosurgery, Tribhuvan University Institute of Medicine, Maharajgunj 44600, NepalAbstractTarlov cyst is a type II meningeal cyst most commonly found in the sacral region. It is mostly asymptomatic, but it may present with low back pain and bowel or bladder symptoms. Most of these cysts are incidentally found on imaging. Symptomatic Tarlov cysts are extremely rare, commonly presenting as sacral or lumbar syndromes or rarely as cauda equina syndrome. We present a 28-year-old male with sacral Tarlov cyst, back pain, and urinary symptoms who was successfully managed surgically. We report this case to increase awareness of this rare entity.Keywords: Surgical management, Tarlov cyst, urinary symptomsIntroductionThe perineural cyst was found incidentally during an autopsy by Tarlov in 1938 and is known as the Tarlov cyst. It is a benign cerebrospinal fluid (CSF) filled cyst of the spinal roots[1]. The etiology of the Tarlov cyst is unknown, but cyst growth may result from valve-like microcommunication permitting only the influx of CSF [2]. These cysts are often multiple and appear on dorsal nerve roots, most commonly in the sacral region. Most cysts remain asymptomatic and are found incidentally on imaging for other symptoms and signs. Few give symptoms like pain, which can also be associated with bowel or bladder symptoms.Surgical removal of perineural cysts is recommended if it is symptomatic and not manageable medically [3]. These cysts can also be managed conservatively with oral steroids and transforaminal epidural steroids.[4]We report a case of a 28-year-old male who had low back pain with bladder and bowel symptoms caused by a sacral perineural cyst. He was treated surgically with cyst fenestration.Case history and examinationA 28-year-old right-handed male presented with a history of difficulty in passing stool for one and a half years, which was then followed by increased frequency of urination. Constipation was gradual in onset and progressive. He then developed lower back pain, which radiated to the right lower limb. He occasionally developed a tingling sensation in the lateral aspect of the left lower limb up to the ankle, which was aggravated due to constipation and was relieved only after passing stool. The patient developed difficulty in passing urine and had to use clean intermittent catheterization (CIC) to clear the bladder. There was no history of trauma, fever, or limb weakness. In the past, he had undergone a right inguinal hernioplasty.On examination, the patient had a normal straight leg raising test and normal power and sensations in bilateral lower limbs.For the urinary symptoms, the patient was evaluated by a Urologist with a cystoscopy, which showed a normal compliant bladder with a thin stream of urine flow. Equivocal obstruction was observed with slightly weak contractibility. Micturating cystourethrogram (MCU) found a cone-shaped urinary bladder with increased volume.Differential diagnosis, investigation and treatmentHis lower back pain was persistent and was later evaluated with MRI of the lumbosacral spine, which showed a fluid signal intensity lesion (82x22x11mm) in the central spinal canal in the S2, S3, S4, and S5 sacral vertebra. The lesion extends into the right neural foramina of the S3-S4 level. (fig1)
