Table 2.
Baseline Functional and Structural Measures
| Clinical Diagnosis | |||
|---|---|---|---|
| Overall N=127 | USH2 N = 80 | ARRP N = 47 | |
|
| |||
| VTOT (dB-sr) a | |||
| Median (IQR) | 20.6 (7.7, 46.3) | 16.0 (3.6, 35.2) | 32.8 (15.1, 54.6) |
| [Min, Max] | [0.2, 90.5] | [0.2, 81.4] | [2.5, 90.5] |
| Mean (SD) | 27.8 (23.7) | 22.5 (21.5) | 37.1 (24.7) |
| V30 (dB-sr) a | |||
| Median (IQR) | 8.3 (3.8, 12.8) | 7.5 (2.7, 12.7) | 9.3 (5.1, 13.3) |
| [Min, Max] | [0.2, 22.7] | [0.2, 21.6] | [1.4, 22.7] |
| Mean (SD) | 9.0 (5.9) | 8.4 (5.9) | 10.0 (5.9) |
| SP mean sensitivity (dB) a | |||
| Median (IQR) | 9.3 (5.2, 14.6) | 7.8 (4.3, 13.8) | 12.1 (7.0, 16.9) |
| [Min, Max] | [0.4, 24.6] | [0.4, 24.2] | [2.4, 24.6] |
| Mean (SD) | 10.2 (6.1) | 9.3 (6.0) | 11.9 (6.0) |
| I4e seeing area (deg 2 ) b | |||
| Median (IQR) | 85.8 (22.2, 607.0) | 61.4 (12.8, 289.2) | 187.7 (27.1, 1770.0) |
| [Min, Max] | [0.0, 8883.1] | [0.0, 5619.2] | [0.0, 8883.1] |
| III4e seeing area (deg 2 ) b | |||
| Median (IQR) | 2454.6 (431.6, 8064.4) | 1362.5 (226.1, 6465.6) | 5722.6 (2112.7, 9707.6) |
| [Min, Max] | [6.7, 13467.0] | [6.7, 13335.0] | [105.9, 13467.0] |
| V4e seeing area (deg 2 ) b | |||
| Median (IQR) | 8798.5(2619, 12344.0) | 5912.5 (842.4, 11521.0) | 11062.0 (7389.4, 13035.0) |
| [Min, Max] | [18.6, 15800.0] | [18.6, 15579.0] | [405.5, 15800.0] |
| VA ETDRS letter score c | |||
| Median (IQR) | 80.0 (75.0, 85.0) | 79.0 (73.5, 85.0) | 82.0(77.0, 87.0) |
| [Min, Max] | [18.0, 94.0] | [18.0, 92.0] | [41.0, 94.0] |
| Photopic ERG 30 Hz flicker | |||
| Amplitude (μV)d | |||
| N of unmeasurable (0) amplitudes | 37 (29%) | 25 (32%) | 12 (26%) |
| Median amplitude (IQR) | 2.0 (0.0, 7.7) | 1.5 (0.0, 5.5) | 3.1 (0.0, 20.0) |
| [Min, Max] | [0.0, 82.2] | [0.0, 82.2] | [0.0, 60.0] |
| MP mean retinal sensitivity e | |||
| Median (IQR) | 4.1 (2.5, 8.5) | 3.8 (2.2, 8.6) | 5.4 (2.7, 8.6) |
| [Min, Max] | [0.2, 22.8] | [0.2, 22.8] | [0.5, 19.2] |
| Mean (SD) | 6.0 (4.9) | 5.5 (4.9) | 6.6 (5.3) |
| Presence of cysts f | |||
| Yes | 55 (43%) | 39 (49%) | 16 (34%) |
| No | 70 (55%) | 39 (49%) | 31 (66%) |
| Ungradable | 2 (2%) | 2 (2%) | 0 |
| Central subfield thickness (microns) f | |||
| Median (IQR) | 253.0 (228.0, 285.0) | 247.0 (223.0, 280.0) | 261.0 (246.0, 288.0) |
| [Min, Max] | [137.0, 519.0] | [137.0, 519.0] | [175.0, 323.0] |
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).
Kinetic perimetry results were graded by a reading center. Seeing area was calculated as isopter area minus scotoma. Scotoma not tested/measured was treated as 0 in the calculation. 49 participants in the USH2 group and 24 participants in the ARRP group have scotomas not tested/measured and treated as 0. 21 participants in the USH2group and 8 participants in the ARRP group have III4e scotomas not tested/measured and treated as 0 (1 subject was excluded for procedure issues). 28 participants in the USH2group and 14 participants in the ARRP group have V4e scotomas not tested/measured and treated as 0 (2 subjects were 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 USH2 group (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 USH2 and 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 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 USH2 group (due to ungradable image).