Anterior sacral meningocele in an adult with chronic constipation: Surgical management through a posterior approach

Background: Anterior sacral meningocele (ASM) is a rare form of congenital spinal dysraphism in which the meninges herniate through an anterior sacral defect into the presacral space. Symptomatic lesions may present with pelvic or gastrointestinal symptoms and may be correlated with preserved neurological function. Case Description: A 32-year-old female presented with progressive constipation, abdominal distension, and pelvic fullness but remained neurologically intact with normal sphincter function. The magnetic resonance imaging (MRI) demonstrated a 9 × 6.5 cm cerebrospinal fluid (CSF)-containing presacral lesion communicating with the thecal sac through an anterior sacral S4–S5 defect, with anterior displacement of the rectum. The patient underwent a posterior sacral approach with decompression of the meningocele, closure of the communicating fistulous defect, preservation of the functional sacral roots, and watertight dural closure. Postoperatively, her bowel symptoms improved. The follow-up MRI demonstrated marked reduction of the lesion without recurrent CSF collection. Conclusion: Symptomatic ASM may present in adults with gastrointestinal symptoms despite preserved neurological and sphincter function. MRI scans best define the sacral defect and identify the site of thecal communication with the meningocele, thus helping to guide surgical occlusion of the fistulous/CSF tract.