DeCure for Stromal corneal dystrophy

A 32-year-old male with pre-Descemet membrane corneal dystrophy was examined by three imaging modalities. In vivo confocal microscopy showed pleomorphic hyperreflective particles both inside and outside cells in the anterior and mid stroma, with increased reflectivity of some keratocytes that remained normal in size; these changes grew more severe from anterior to mid stroma. The posterior stroma contained grossly enlarged hyperreflective keratocytes with prominent processes, and hyperreflective particles were scattered on the endothelium. Anterior segment optical coherence tomography revealed a well-delineated homogeneous band of increased reflectivity about 70 μm wide in the posterior stroma only, with a normal-appearing anterior and mid stroma. Scheimpflug corneal densitometry measured a higher amount of backscattered light from the posterior stroma, with a posterior-to-anterior ratio of 0.8. The authors concluded that although structural changes appear limited to the posterior stroma clinically and on OCT, the pathology involves the entire corneal stroma and endothelium.

A separate report described a 31-year-old man with bilateral symmetric central discoid corneal stromal opacification who underwent bilateral penetrating keratoplasties for decreased visual acuity, glare, and photophobia. Light microscopy showed multiple extracellular vacuoles concentrated in the anterior half of the central stroma; material within the vacuoles stained intensely with alcian blue and colloidal iron, consistent with glycosaminoglycan deposition. Transmission electron microscopy demonstrated non-membrane-bound vacuoles containing a faintly osmiophilic matrix and black circular profiles. Immunohistochemistry identified chondroitin sulfate as the primary glycosaminoglycan. No systemic storage disorder was found, and genetic analysis revealed no mutation in the coding region of the CHST6 gene. The authors considered this a previously unreported dominantly inherited stromal dystrophy, with nearly identical findings in the patient’s father and one of four brothers.

A 2024 study tested a new surgical technique called intracorneal selective stromal transplantation in a 62-year-old patient with stromal degeneration and intact corneal layers between the altered stroma and Descemet’s membrane posteriorly and Bowman’s layer anteriorly; the patient also had immature senile cataract. The pathologically altered stroma was removed and replaced with a graft in the optical centre, while endothelium, Descemet’s membrane, and Bowman’s layer remained intact. Best-corrected visual acuity improved from 0.01 to 0.6, and mean endothelial cell density did not change over 24 months of follow-up. The authors concluded that the method can be used in patients with preserved endothelial cells, intact Descemet’s membrane, and intact Bowman layer, but noted that only one clinical case has been reported and that further long-term observation and more cases are required.

A 2023 review summarised that corneal dystrophies are bilateral genetically determined non-inflammatory diseases, usually autosomal dominant, and that mutations in genes including CHST6, KRT3, KRT12, PIP5K3, SLC4A11, TACSTD2, TGFBI, and UBIAD1 have been identified. Diagnosis is still typically made on clinical grounds. Treatment depends on opacity location and visual acuity; observation is recommended for asymptomatic cases with high acuity, while phototherapeutic keratectomy or various keratoplasty modifications are used for pronounced opacities. What remains missing are large prospective trials comparing surgical techniques, validated patient stratification by genetic subtype and disease stage, and funding for long-term follow-up of novel procedures such as intracorneal selective stromal transplantation.