Ossified pseudomeningocele after the removal of an intradural neurinoma in the lumbar spine. A case report and literature review

Abstract

The study objective is to describe a case of ossified pseudomeningocele after spinal surgery and to develop an optimal treatment strategy for this disorder.Materials and methods. We report a case of ossified pseudomeningocele developed after the removal of an intradural neurinoma in the lumbar spine in a female patient treated in the Clinic for Nervous Diseases, University Clinical Hospital No. 3 of the I.M. Sechenov First Moscow State Medical University in 2017. We also reviewed research literature describing this pathological condition.Results. Upon admission, the patient was diagnosed with paresis of the left foot occurring in ankle joint dorsiflexion (score 4), absence of the Achilles reflex on the left side, and hypoesthesia of two first toes of the left foot. Magnetic resonance imaging revealed a postoperative cyst of irregular shape located in soft tissues at the level of L vertebral body and compressing the dural sac. The patients underwent surgery that included separation of the pseudomeningocele cavity from the dural sac and placement of an external lumbar drainage. In the postoperative period, we observed a complete regression of neurological symptoms.Conclusion. Since ossified pseudomeningocele in the lumbar spine is extremely rare, an optimal treatment strategy has not been developed so far. We believe that maximum possible excision of the cyst wall and anastomotic sealing with a muscular or fat flap with biological glue followed by flap fixation from the extradural space is a simple and robust method of decompression and separation of the anastomosis. To eliminate the cavity in soft tissue of the paravertebral space, we recommend reconstruction of epidural fat with additional sealing using biological glue. To prevent anastomosis recurrence, we recommend placing an external lumbar drainage.