Table 6.
Correlation of VTOT with Other Baseline Functional and Structural Measures
| Overall | Clinical Diagnosis | Correlation Coefficientb | P Valueb | |||||
|---|---|---|---|---|---|---|---|---|
| USH2 | ARRP | |||||||
|
| ||||||||
| N=126a | VTOTa Mean (SD) |
N=80 | VTOTa Mean (SD) |
N=46 | VTOTa Mean (SD) |
|||
|
| ||||||||
| III4e seeing area (deg 2 ) c | 0.93 | <0.001 | ||||||
| <710 | 40 | 5.8 (6.1) | 36 | 5.8 (6.3) | 4 | 5.4 (4.0) | ||
| [710, 4000) | 33 | 19.0 (8.7) | 19 | 20.8 (9.0) | 14 | 17.0 (8.2) | ||
| [4000, 8000) | 25 | 38.7 (12.4) | 13 | 37.4 (11.4) | 12 | 40.1 (13.9) | ||
| >=8000 | 27 | 61.8 (15.5) | 12 | 58.8 (17.4) | 15 | 64.1 (13.9) | ||
| VA ETDRS letter score (approx. Snellen equivalent) d | 0.59 | <0.001 | ||||||
| <69 (<20/40) | 14 | 8.6 (12.6) | 11 | 3.3 (3.1) | 3 | 27.9 (16.4) | ||
| 69–73 (20/40) | 13 | 15.8 (19.4) | 9 | 12.7 (17.6) | 4 | 22.9 (23.9) | ||
| 74–78 (20/32) | 24 | 19.1 (15.8) | 17 | 17.8 (12.5) | 7 | 22.1 (22.8) | ||
| 79–83 (20/25) | 33 | 24.1 (20.9) | 18 | 19.2 (18.1) | 15 | 30.0 (23.1) | ||
| >=84 (>=20/20) | 42 | 45.8 (22.6) | 25 | 39.9 (23.1) | 17 | 54.5 (19.5) | ||
| Photopic ERG 30 Hz flicker amplitudes (μV)e | 0.54 | <0.001 | ||||||
| 0 | 37 | 16.9 (16.6) | 25 | 14.5 (16.7) | 12 | 22.1 (15.8) | ||
| (0, 1.8) | 20 | 13.9 (12.4) | 15 | 12.8 (13.0) | 5 | 17.2 (10.8) | ||
| [1.8, 6.8) | 34 | 27.1 (21.2) | 24 | 27.7 (22.9) | 10 | 25.7 (17.6) | ||
| >=6.8 | 34 | 48.9 (23.9) | 15 | 37.7 (24.2) | 19 | 57.8 (20.2) | ||
| MP mean retinal sensitivity (dB) f | 0.55 | <0.001 | ||||||
| <2 | 16 | 20.6 (18.6) | 12 | 14.4 (15.8) | 4 | 39.3 (14.0) | ||
| [2, 4) | 28 | 23.3 (19.2) | 17 | 20.9 (16.3) | 11 | 27.0 (23.4) | ||
| [4, 8) | 21 | 31.0 (23.6) | 11 | 24.4 (21.2) | 10 | 38.3 (25.0) | ||
| >=8 | 26 | 53.3 (20.5) | 15 | 47.1 (21.9) | 11 | 61.8 (15.4) | ||
| Presence of cysts g | N/A | 0.03 | ||||||
| Yes | 55 | 23.1 (23.0) | 39 | 20.2 (20.3) | 16 | 30.4 (28.0) | ||
| No | 69 | 32.2 (23.7) | 39 | 25.6 (22.8) | 30 | 40.7 (22.4) | ||
| Ungradable | 2 | 6.4 (6.2) | 2 | 6.4 (6.2) | 0 | NA | ||
| Central subfield thickness (μm) g | 0.48 | <0.001 | ||||||
| <230 | 32 | 11.7 (12.9) | 28 | 8.7 (10.4) | 4 | 32.2 (10.6) | ||
| [230, 250) | 22 | 28.8 (23.1) | 13 | 28.7 (24.6) | 9 | 28.9 (22.2) | ||
| [250, 280) | 33 | 30.2 (25.3) | 18 | 24.6 (23.4) | 15 | 36.8 (26.7) | ||
| >=280 | 38 | 39.2 (23.1) | 20 | 36.2 (19.6) | 18 | 42.6 (26.5) | ||
Static perimetry results were graded by a reading center. Results are based on the average of 3 fields when 3 tests were performed (primary cohort); otherwise they based on just the 1 test performed (secondary cohort). Static perimetry data is not included for 1 participant in the ARRP group (participant was not tested).
Correlation coefficients and p-values are based on analyses combining all participants (both USH2and ARRP groups). Factors are presented categorically to show the data but were analyzed using continuous version of the factor in the analysis.
Kinetic perimetry results were graded by a reading group and 8 participants in ARRP group have III4e scotoma not tested/measured and treated as 0 (1 subject was excluded for procedure issues).
5 sites used an ETDRS chart, 10 sites use an electronic visual acuity tester, and 1 site used both
Photopic ERG 30 Hz flicker amplitudes are not included for 1 participant in the USH2group (participant was not tested)
Microperimetry mean retinal sensitivity results were graded by a reading center. Results are based on the average of first two (out of three) tests. Microperimetry mean retinal sensitivity data are not included for 25 participants in the USH2and 10 participants in the ARRP group (reasons include: 22 not performed in secondary cohort per protocol; in the primary cohort, 10 were not performed because the site did not have the equipment, 2 were MP not done, 1 was ungradable).
Presence of any cyst and central subfield thickness on OCT were graded by a reading center. Central subfield thickness data are not included for 1 participant in the USH2group (due to ungradable image). The P-value for presence of any cyst was calculated using T-test.