Late-onset interface fluid syndrome: A case report and literature review.

Purpose: To present a case of late-onset interface fluid syndrome (IFS) and a literature review on this rare clinical entity.

Introduction: IFS is an uncommon complication of laser in situ keratomileusis (LASIK). Although generally appearing in the early postoperative period, IFS has been reported even years after LASIK.

Methods: A case report of IFS manifesting 19 years after uneventful LASIK, which prompted a literature search for similar, late-onset cases in MEDLINE PubMed. This article reports on a case of IFS appearing 19 years after LASIK surgery, including extensive patient history and analytical presentation of clinical findings, ancillary testing, and short-term follow-up. Furthermore, a literature search for similar cases was performed on MEDLINE, focusing on the etiology and management of late-onset IFS.

Results: Through thorough ancillary testing, the interface fluid was attributed to elevated intraocular pressure (IOP) arising from primary open-angle glaucoma. Antiglaucoma drops resulted in complete fluid regression. A narrative review was conducted based on the 29 case reports that were recovered from the literature search.

Conclusion: IFS represents an uncommon complication that could appear years after LASIK. Careful clinical examination and anterior segment optical coherence tomography promote early diagnosis. Similar cases may manifest due to elevated IOP of variable etiology or as a result of endothelial dysfunction. Depending on the etiology, IOP control or keratoplasty may resolve the condition.