Stem Cell Ophthalmology Treatment Study (SCOTS): bone marrow derived stem cells in the treatment of Usher syndrome

Usher syndrome is the most common form of syndromic retinitis pigmentosa and includes types I, II, and III with varying degrees of hearing loss. We present results of 10 eyes with Usher syndrome treated with autologous bone marrow derived stem cells (BMSC) within the Stem Cell Ophthalmology Treatment Study (SCOTS).

Preoperative Snellen visual acuities ranged from 20/30-1 to 20/400 with the average pre-operative Snellen acuity approximately 20/85 and the average logarithm of the minimum angle of resolution (LogMAR) acuity 0.635. All eyes had significantly impaired visual fields and patients reported hearing loss as part of this syndromic retinitis pigmentosa. Treatment using the protocols of the SCOTS study using BMSC provided by retrobulbar, subtenons, intravitreal and intravenous injections.

Following treatment, 80% of the Usher eyes showed an improvement in visual acuity. Of the eyes that improved the average increase in visual acuity was 36.4% on LogMAR with improvements ranging from 23% to 94%. The average post-operative change in all treated eyes was a gain of 0.18 LogMAR and an increase in visual acuity of 28.3% on LogMAR. The results showed high statistical significance with P<0.001. Visual fields generally improved. No patient experienced a loss of vision. One patient underwent preoperative and 4-month post-operative audiometry testing which demonstrated improvement. The procedures were performed safely and without complications.

Findings confirm meaningful improvement in visual acuity is possible in Usher syndrome using BMSC protocols developed in the SCOTS study. Statistical significance and safety were established.