Cystic dilation of the ventriculus terminalis.

Object. The ventriculus terminalis, an embryological remnant consisting of the ependymal-lined space of the conus medullaris, can occasionally become symptomatic after cystic dilation. In the existing literature, consisting of 32 cases, the preferred type of management (conservative vs surgical) is still debated. The object of this study was to report the surgical results in a consecutive series of 10 adult patients with cystic dilation of the ventriculus terminalis (CDVT), to match them with data retrieved from the relevant literature, and specifically to validate a new recent clinical classification. Methods. The authors reported 13 new cases of CDVT treated in the Department of Neurosurgery at University Hospital in Verona, Italy. Treatment modalities and clinical and radiological outcomes, both early and at follow-up, were analyzed and compared with a preoperative classification of clinical presentation, as established by de Moura Batista and colleagues (2008). Results. Surgical treatment seemed to guarantee the resolution of CDVT. Dorsolumbar laminotomy, myelotomy, and cystic drainage were performed in 10 patients. Patients with Type I symptoms (nonspecific complaints) often presented with comorbidities (herniated disc or facet hypertrophy) confusing their clinical status. The surgical treatment of patients with Type I symptoms promoted good results only if the diagnosis of CDVT was definitive and symptoms had rapidly evolved. In patients with Type II (focal neurological deficits) and III (sphincter disturbances) symptoms, surgical treatment sustained improvement even at the late follow-up. Conclusions. While confirming the usefulness of de Moura Batista and colleagues' classification in its impact on prognosis, the authors propose a revision of the classification with subgroups Type Ia (nonspecific symptoms without clear relation to CDVT), which is best treated conservatively, and Type Ib (rapid onset and invalidating unspecific complaints without comorbidities), which may benefit from surgical evacuation. (http://thejns.org/doi/abs/10.3171/2012.4.SPINE11504)