Responsiveness of the Scale for the Assessment and Rating of Ataxia and Natural History in 884 Recessive and Early Onset Ataxia Patients.

OBJECTIVE: The Scale for the Assessment and Rating of Ataxia (SARA) is the most widely applied clinical outcome assessment (COA) for genetic ataxias, but presents metrological and regulatory challenges. To facilitate trial planning, we characterize its responsiveness (including subitem-level relations to ataxia severity and patient-focused outcomes) across a large number of ataxias, and provide first natural history data for several of them. METHODS: Subitem-level correlation and distribution-based analysis of 1,637 SARA assessments in 884 patients with autosomal recessive/early onset ataxia (370 with 2-8 longitudinal assessments) were complemented by linear mixed effects modeling to estimate progression and sample sizes. RESULTS: Although SARA subitem responsiveness varied between ataxia severities, gait/stance showed a robust granular linear scaling across the broadest range (SARA < 25). Responsiveness was diminished by incomplete subscale use at intermediate or upper levels, nontransitions ("static periods"), and fluctuating decreases/increases. All subitems except nose-finger showed moderate-to-strong correlations to activities of daily living, indicating that metric properties-not content validity-limit SARA responsiveness. SARA captured mild-to-moderate progression in many genotypes (eg, SYNE1-ataxia: 0.55 points/yr, ataxia with oculomotor apraxia type 2: 1.14 points/yr, POLG-ataxia: 1.56 points/yr), but no change in others (autosomal recessive spastic ataxia of Charlevoix-Saguenay, COQ8A-ataxia). Whereas sensitivity to change was optimal in mild ataxia (SARA < 10), it substantially deteriorated in advanced ataxia (SARA > 25; 2.7-fold sample size). Use of a novel rank-optimized SARA without subitems finger-chase and nose-finger reduces sample sizes by 20 to 25%. INTERPRETATION: This study comprehensively characterizes COA properties and annualized changes of the SARA across and within a large number of ataxias. It suggests specific approaches for optimizing its responsiveness that might facilitate regulatory qualification and trial design. ANN NEUROL 2023;94:470-485.

Scleral buckling versus primary vitrectomy in rhegmatogenous retinal detachment study (SPR study): Risk assessment of anatomical outcome. SPR study report no. 7.

PURPOSE: The 'Scleral buckling versus primary vitrectomy in rhegmatogenous retinal detachment study' (SPR study) is a randomized multicentre trial comparing primary vitrectomy (PV) and scleral buckling surgery (SB) for rhegmatogenous retinal detachment (RRD). This subanalysis was conducted to identify risk factors associated with anatomical outcomes. METHODS: Relating the anatomical success results at the 1-year follow-up visit to pre- and intraoperative findings using multivariate statistical methods. RESULTS: In the phakic subtrial, anatomical success was negatively associated with the number of breaks (p < 0.0001), break extension > 1 clock hour (p = 0.0005) and intraoperative use of cryotherapy (p = 0.0484). It was positively associated with retinal breaks with irregular edges (p = 0.0353) and subretinal fluid drainage (p = 0.0155). In the pseudophakic/aphakic subtrial, anatomical success was negatively associated with the number of retinal breaks (p = 0.0004) and previous YAG capsulotomy (p = 0.0256), and the combined effect of the surgical procedure and intraoperative use of laser (p = 0.0229). CONCLUSION: Primary anatomical success is an important result for patients undergoing RRD surgery. Our data demonstrate that the final anatomical outcome is related to a higher preoperative number of breaks and cryotherapy in phakic eyes. Additional risk factors varied between phakic and pseudophakic subgroups. Our findings may be used to facilitate the prognosis of future patients with RRD.