Supraorbital minicraniotomy for open Ommaya reservoir placement in pediatric craniopharyngiomas: a case series and technical report

OBJECTIVE Craniopharyngiomas with a predominant cystic component are often seen in children and can be treated with an Ommaya reservoir for aspiration and/or intracystic therapy. In some cases, cannulation of the cyst can be challenging via a stereotactic or transventricular endoscopic approach due to its size and proximity to critical structures. In such cases, a novel placement technique for Ommaya reservoirs via a lateral supraorbital incision and supraorbital minicraniotomy has been used. METHODS The authors conducted a retrospective chart review of all children undergoing supraorbital Ommaya reservoir insertion from January 1, 2000, to December 31, 2022, at the Hospital for Sick Children, Toronto. The technique involves a lateral supraorbital incision and a 3 x 4-cm supraorbital craniotomy, with identification and fenestration of the cyst under the microscope and insertion of the catheter. The authors assessed baseline characteristics and clinical parameters of surgical treatment and outcome. Descriptive statistics were conducted. A review of the literature was performed to identify other studies describing a similar placement technique. RESULTS A total of 5 patients with cystic craniopharyngioma were included (3 male, 60%) with a mean age of 10.20 +/- 5.72 years. The mean preoperative cyst size was 11.6 +/- 3.7 cm3, and none of the patients suffered from hydrocephalus. All patients suffered from temporary postoperative diabetes insipidus, but no new permanent endocrine deficits were caused by the surgery. Cosmetic results were satisfactory. CONCLUSIONS This is the first report of lateral supraorbital minicraniotomy for Ommaya reservoir placement. This is an effective and safe approach in patients with cystic craniopharyngiomas, which cause local mass effect but are not amenable to traditional Ommaya reservoir placement stereotactically or endoscopically.