This article reports the clinical presentation, ophthalmologic examination, and imaging features of a 5-year-old girl with Dandy-Walker syndrome (DWS). She underwent partial resection of an arachnoid cyst in the posterior cranial fossa after the diagnosis of DWS. However, her visual acuity continued to deteriorate after the surgery, and the ophthalmologic follow-up revealed progressive thinning of the retinal nerve fibers layer (RNFL), suggesting that the intracranial pressure (ICP) had not yet been effectively controlled, and the damage to the optic nerve was further developing. However, due to the special pathological changes of DWS, MRI and routine lumbar puncture was not able to exactly identify the supratentorial ICP, subsequent ICP measurement through the lateral ventricle confirmed that increased ICP was still existed. After performing a right ventriculoperitoneal shunt, the child's binocular vision improved, and the thickness of the RNFL in both eyes remained stable. Current treatment modalities for DWS include cystectomy, cerebrospinal fluid shunt and endoscopic third ventriculostomy. The measurement of postoperative ICP in DWS patients is complicated, because there may be a significant pressure gradient between the supratentorial and infratentorial regions, which is not accurately reflected by lumbar puncture manometry, and intraventricular manometry is much more invasive. Ophthalmologic examinations including progressive decrease in RNFL thickness, optic disc edema, and abnormal retinal vascular morphology are required to provide evidences of increased ICP. These examinations are noninvasive, simple, and repeatable. They are an effective means of assessing ICP, and are recommended to be included in the routine management of ICP in patients with DWS after surgery.
