Abstract
Purpose:
Retinitis Pigmentosa (RP), the most common inherited retinal degenerative disease is genetically and clinically heterogeneous and affects approximately 1 in 4,000 individuals worldwide. The severity and progression is variable and difficult to determine due to the wide range of genetic mutations, however knowledge of inheritance pattern, duration of the disease and mutation type all have a bearing on prognosis. In 2005 our group constructed and presented data on the Retinitis Pigmentosa Severity Assessment Scale (RPSAS) (ARVO abstract number 1419). The aim of the RPSAS was to devise a tool to facilitate quantification of phenotypic progression, which would be useful for patient counselling and in future clinical trials. The aims of the current project are: 1) To refine the original RPSAS now entitled the REtinal ASSESsment Scale (REASSESS) 2) To present progression scores on patients with longitudinal data (not available in 2005) 3) To correlation progression scores with inheritance pattern and genotypes where available.
Methods:
The REASSESS scoring sheet includes data on the following parameters. Best corrected distance and near visual acuity, visual fields and contrast sensitivity. Standard images have been constructed for grading of pigmentary changes, optic disc pallor and vascular attenuation. The predominant type of retinal pigmentation, degree of macular atrophy and electrophysiology results are also scored. The maximum score for the REASSESS form is 45 points. We have repeated the assessment on the patients with retinitis pigmentosa (RP) who had a RPSAS score in 2005 with a view to determining progression.
Results:
We selected four patient groups, Autosomal Recessive, Autosomal Dominant RP, Sporadic RP and Usher Syndrome. To date 19 patients have been re-examined and the trend is that the REASSESS score shows an increase from 2005 to 2013. Correlations with inheritance pattern and genotypes are ongoing.
Conclusions:
The new REASSESS is more specific when used to determine phenotype progression. Results from our pilot study show an increase in the REASSESS score from 2005 to 2013, which would indicate progression. We believe this scale to be a valuable tool for patient counselling and to document progression in clinical trials.
Keywords: 696 retinal degenerations: hereditary •
494 degenerations/dystrophies