LAUSR

Neurenteric cysts (NECs) are rare, congenital malformations of the central nervous system that are lined by an epithelium of an intestinal nature. They are benign lesions often found in the cervical and upper thoraco-cervical areas. The lesions commonly present in the second decade of life and are usually located ventral or ventrolateral to the cord in the intradural compartment. According to a recent review of postsurgical outcome analyses, incomplete posterior surgical excision carries a higher cumulative risk of recurrence as the follow-up period increases. However, some previous reports described cyst recurrences that needed revision surgeries. Asymptomatic cases with cyst recurrence are not well-known. We report here cervical/thoracic intradural extramedullary NECs that were surgically removed and recurred without neurological symptoms. A 4-year-old girl presented with neck pain that had persisted for 1 week. She complained of severe neck pain with difficulty urinating at the time of admission to our hospital. Neurological examination revealed spastic paralysis in both lower extremities without sensory disturbance. Magnetic resonance imaging (MRI) revealed an intradural cyst located anterior to the spinal cord at the C3 to C5 level (Fig. 1A-C). A hemilaminectomy was performed at C2 to C6. The spinal cord shifted posteriorly. A gray-white cyst appeared anterior to the spinal cord. After the cyst wall was punctured, milky white fluid was aspirated. After the operation, there was immediate improvement in the neck pain and urinary disturbance. However, 2 months later, she complained of severe neck pain again with muscle weakness in the right upper extremities. MRI revealed cyst recurrence (Fig. 1D, E). During the second surgery, we detached the cyst wall from the spinal cord, following excision. We tried to completely remove the cyst wall but found severe adhesion between the cyst wall and the pia mater. Therefore, complete removal of the wall would have involved spinal damage. Thus, we performed a cyst wall resection (Fig. 2A). Histopathological examination of the tissue demonstrated a cyst wall lined with cuboidal to columnar epithelium, suggesting a type A Wilkins and Odom neurenteric cyst histopathological classification (Fig. 2B). The patient subsequently recovered from the neurological deficit. The cyst recurred 1 year later. We monitored her for 11 years without any symptoms, and the recurrent cyst has diminished in size year by year. (Fig. 1FH). Here, we presented a NECs case that underwent surgical treatment. Although gross removal of the cyst wall was achieved, the cyst recurred without symptoms after the surgeries. During postoperative follow-up, no neurological symptom was observed. Although we performed reoperation through the previous laminectomy, it would be better to carry out laminoplasty to get a wider surgical field, enabling us to remove the cyst as much as possible. Surgical treatment in NECs should be done to prevent spinal irritation. Indeed, the dorsal wall of the cyst was adhered tightly to the spinal cord in our case. Miyoshi et al reported that if the adhesion was tough and some portion of the cyst was intramedullary, complete resection could result in postoperative neurologic deterioration. Moreover, several previous reports advised against overaggressive removal of the lesion because of the benign course after subtotal resec-