spinal meningocele is associated with spina bifida cysts and may occur at any age . however , intrapelvic meningocele is rare and , without spinal compression , this type of meningocele does not cause any discomfort . for this reason , intrapelvic meningocele has not attracted much attention for a long time . here , we report a case of an asymptomatic intrapelvic meningocele found incidentally during a sigmoidectomy due to megacolon in a 30-year old male patient . a 30-year - old male , admitted because of constipation , was scheduled to undergo sigmoidectomy . preoperative magnetic resonance ( mr ) scan indicated that a cyst was in front of the third sacral vertebrae ( s3 ) ( fig . after sigmoidectomy , this cyst was resected . however , on the first postoperative day , 150 ml of amber liquid was drained from pelvic drainage tube . over the following several days 1c and 1d ) . because the patient had just undergone sigmoidectomy , conservative treatment consisting of three main steps was considered : drainage , anti - infection therapy ( cefpiramide combined with tinidazole ) and posturing by raising the position of the lumbosacral region to reduce liquorrhoea . at the beginning , we drained the cerebrospinal fluid ( csf ) via a pelvic drainage tube . however , because the volume still exceeded 150 ml / d , we placed another drainage tube into the subarachnoid space . on the first day , approximately 300 ml csf drained from the subarachnoid tube , and 50 ml drained from the pelvic cavity . over the following three days , the volume of liquid from the pelvic cavity began to reduce generally . the subarachnoid drainage tube was removed on the fourth day and there was no liquorrhoea over the next two days . mr scan reveals the presence of a cyst 3 cm in diameter ( arrow ) in front of s3 in a 30-year - old male patient ( a : coronal section ; b : median sagittal section ) . histological examination ( c : 40 ; d : 100 ) showed that the cyst was mixed with nerve collagen tissue ( h&e ) . intrapelvic meningocele is defined as a csf - filled sac within the spinal meningeal wall which protrudes into the intrapelvic cavity through an enlarged intervertebral foramen or bone defect . acquired meningocele is relatively common as a laminectomy complication , while congenital meningocele is commonly associated with neurofibromatosis , . the clinical manifestation of an intrapelvic meningocele is closely related to its size and relationship with surrounding structures . it may include back pain , urinary and fecal incontinence , and lower limbs weakness or paralysis . a small lesion may be asymptomatic and discovered incidentally , as it was in our case . for small- and medium - sized lesions , the most common surgical management is resection of the meningocele and repair of the dural defect through laminectomy , . in this case , surgery was performed with removal of the meningocele pouches and shunting of the cyst to the subarachnoid region . however , liquorrhoea occurred after the operation . although liquorrhoea is a common occurance with cystectomy , it may result in infection of the central nervous system . specific posture and drainage in combination with anti - infection therapy were performed instead of surgery . this conservative method can also treat liquorrhoea effectively and at the same time help patients avoid a second operation .