Neuro-ophthalmic features of patients with spontaneous cerebrospinal fluid leaks

Increased intracranial pressure is a potential cause of spontaneous cerebrospinal fluid (sCSF) leak. Associated neuro-ophthalmic features have not been well studied, particularly relationships with idiopathic intracranial hypertension (IIH). We hypothesized that neuro-ophthalmic features routinely used in evaluations for IIH can be useful in the investigation of a causal relationship between IIH and sCSF leak. We reviewed the neuro-ophthalmic examination and office-based ophthalmic imaging data of all consecutive patients with sCSF leaks and at least one repair to investigate the clinical and neuro-ophthalmic features of increased intracranial pressure.

We conducted a retrospective longitudinal study at a single institution by querying the electronic medical record system for CSF leak Current Procedural Terminology (CPT) codes (G96.00 and G96.01) from June 1, 2019, to July 31, 2022. For patients with a confirmed diagnosis of sCSF leak, demographic information, eye examination results, and ophthalmic imaging details for both eyes were collected.

A total of 189 patients with CSF leaks were identified through CPT coding; 159 had iatrogenic or traumatic CSF leaks, and 30 individuals (3 male, 27 female) had confirmed sCSF leaks. The mean age of patients with sCSF leaks was 46 years (range: 29 - 81), with a mean body mass index of 35.2 kg/m² (range: 18.2 - 54.1). Only 11 of 30 underwent eye examinations (8 before surgical repair and 10 after). The mean pre-repair and post-repair best-corrected visual acuity were 20/30 (range: 20/20 - 20/55) and 20/25 (range: 20/20 - 20/40), respectively (P = 0.188). The mean retinal nerve fiber layer thickness was 99 µm (range: 96 - 104) pre-repair and 97 µm (range: 84 - 103) post-repair (P = 0.195). The mean ganglion cell complex thickness was 84 µm (range: 72 - 94) pre-repair and 82 µm (range: 71 - 94) post-repair (P = 0.500). Humphrey visual field average mean deviation was -5.1 (range: -12.4 - -1.8) pre-repair and -1.0 (range: -10.1 - 2.1) post-repair (P = 0.063).

Serial neuro-ophthalmic examinations are recommended for patients with sCSF leaks to screen for signs of current or prior increased intracranial pressure. Larger studies are required to clarify the longitudinal changes in neuro-ophthalmic features, to investigate the incidence of IIH in cases of sCSF leak development or recurrence after surgical repair, and to explore potential causal relationships to guide post-repair management and prevent recurrent leaks. A multicenter consortium is also suggested to develop a standard clinical protocol for comprehensive management of sCSF leaks.