Cryopexy May Reduce Retinal Detachment After Scleral Buckle in Stickler Syndrome

Peripheral cryopexy in scleral buckle (SB) lowered the risk of retinal detachment (RD) in patients with Stickler syndrome, according to research published in Retina.

Prior research has shown that, in certain cases, ophthalmologists can detect Stickler syndrome, a rare genetic disorder which carries an estimated 80% risk of RD. Treatments to protect the vision in the fellow eye and avoid bilateral detachment are under investigation. Laser and cryopexy treatments may increase retinal adhesion but do not address vitreous traction, which the researchers proposed SB could achieve.

“Due to the high incidence of RD in untreated fellow-eyes and the specificity of genetic testing confirming the diagnosis, Stickler syndrome would represent an ideal condition for systematic prophylaxis if a proven, safe and efficient treatment indeed existed,” according to the investigators.

Data from 52 patients (29 boys, 23 girls mean age at surgery 10.7±2.3 years) with diagnosed (n=49) or suspect (n=3) type 1 Stickler syndrome (n=49) who underwent prophylactic fellow-eye encircling SB from 1996 to 2004 were included in the study. The patients had previously experienced RD in 1 eye. Rhegmatogenous retinal lesions (39 eyes) were treated with cryopexy. Those lesions included retinal tears, lattice degeneration, atrophic retinal holes, and retinal tufts.

The researchers evaluated the patients’ best corrected visual acuity (BCVA), retinal attachment, and need for ancillary or adjunctive treatment through a mean follow-up period of 15.6±2.41 years.

RD with localized detachment and single break occurred in 5 patients (0 with cryopexy, 5 without cryopexy) a mean of 2.6±0.55 years after prophylactic treatment (P =.001). Those eyes were re-attached with revised episcleral surgery and adjunctive cryopexy, with post-op refraction of -1.9±0.74 D and BCVA of 20/25 (0.1±0.07 LogMAR) by end of follow-up.

Mean spherical equivalent changed from -15.1±3.2 diopters at baseline to -18.8±3.4 D at end of follow-up.

Visual acuity at baseline and end of follow-up, the need for adjunctive or ancillary treatment, and BCVA at end of follow-up were not significantly different between the groups.

“Our results suggest vitreous traction relief is important but not as much as the rhegmatogenous component, taking care of which (with cryopexy alone in the Cambridge Protocol, for instance) yields a 12.5% RD rate. The notion that treating only ‘visible’ lesions does not seem to confer enough protection is somewhat discouraging and also implies the inadequacy of a ‘watchful wait,’” according to the researchers. 

“Our results indeed suggest that applying cryo treatment to visible lesions only, which implies not treating unremarkable healthy retina on ophthalmoscopy, does not confer enough protection. In other words, Stickler syndrome does not seem to send premonitory signals of RD, reducing the role of periodical observation and urging preventive action. Applying 360° cryo treatment regardless of the presence of retinal degeneration as advocated by the Cambridge Protocol reached better results than SB alone and could be beneficial for this very reason.”

According to researchers, the invasive procedure of fellow-eye SB is a challenging decision for families of pediatric patients who are “often reluctant to face further risks.”

Reference

Ripandelli G, Rossi T, Pesci FR, et al. The prophylaxis of fellow-eye retinal detachment in Stickler syndrome. A retrospective series. Retina. Published online September 14, 2021. doi:10.1097/IAE.0000000000003304