Table 2.
Summary of the Results of Quantitative Corneal Nerves Assessment with IVCCM in Diabetic Neuropathya
| Studies, first author | n | Age, years | Type of IVCCM | Acquisition method/images assessed per subject | Corneal nerve fiber density | Corneal nerve branch density | Corneal nerve fiber length | Study limitations |
| Sellers58 | 12 | 14.8 ± 2.1 | LSCM | Section/5 images | 24.1 ± 3.1 no/mm2 | 43.7 ± 13.7 no/mm2 | 18.2 ± 2.4 mm/mm2 | Small sample size |
| Zhivov59 | 18 | 68.8 ± 8.8 | LSCM | Section/not specified | 0.006 ± 0.002 mm/mm2 | 25.3 ± 28.6 no/frame | 6222 ± 2419 μm | Small sample size |
| Ahmed43 | 33 | 50 ± 14.3 | LSCM | Volume/2 images | 28.0 ± 9.0 no/mm2 | 17.0 ± 12.0 no/mm2 | 11.1 ± 3.6 mm/mm2 | Image selection criteria |
| Edwards38 | 88 | 58 ± 9 | LSCM | Section/8 images | — | Graphical | Graphical | Corneal nerve fiber density not presented |
| Nitoda60 | 139 | 63 ± 2 | LSCM | Sequence/3–5 images | 23.3 ± 0.8 no/mm2 | 31.8 ± 2.6 no/mm2 | 12.5 ± 2.6 mm/mm2 | — |
| Tavakoli61 | 25 | 52 ± 2 | SSCM | Section/3–5 images | 18.8 ± 2.1 no/mm2 | 6.9 ± 1.5 no/mm2 | 8.3 ± 0.9 mm/mm2 | Small sample size |
| Hertz49 | 26 | 43 ± 16.9 | LSCM | Volume/2 images | 32.5 ± 9.7 no/mm2 | 26.0 ± 17.1 no/mm2 | 13.6 ± 3.5 no/mm2 | Image selection criteria |
| Ishibashi62 | 38 | 46.7 ± 1.6 | LSCM | Not specified/4–5 images | 25.3 ± 1.0 no/mm2 | — | 9.8 ± 0.3 mm/mm2 | — |
| Tavakoli39 | 101 | 58.3 ± 2.2 | SSCM | Section/3–5 images | 24.1 ± 2.6 no/mm2 | 10.3 ± 1.7 no/mm2 | 4.9 ± 0.5 mm/mm2 | — |
| Messmer40 | 67 | 54 | LSCM | Volume and sequence/ 5 images | 16.5 no/mm2 | 17.5 no/m m 2 | 10.2 mm/mm2 | Sample demographics |
| De Cillà63 | 50 | 62.6 ± 6 | LSCM | Not specified/1 image | 2.4 ± 1.0 no/frame | — | — | Image selection and analysis criteria |
| Midena44 | 42 | — | SSCM | — | 2.2 ± 0.3 no/frame | 0.8 ± 0.1 (degree) | — | — |
| Chang41 | 42 | 63.8 ± 7.2 | SSCM | Not specified | 16.1 ± 5.7 no/mm2 | 24.9 ± 7.7 no/mm2 | — | Image selection and analysis criteria |
| Quattrini16 | 54 | 58 ± 10.9 | SSCM | Section/3–5 images | 23.7 ± 3.2 no/mm2 | 7.31 ± 1.98 no/mm2 | 3.94 ± 0.63 mm/mm2 | — |
| Mocan64 | 35 | 58.4 ± 10 | SSCM | Not specified/1 image | 28.3 ± 10.4 | 39.7 ± 13.2 no/mm2 | — | Image analysis criteria |
| Malik42 | 18 | 57 ± 12.8 | SSCM | Section/3–5 images | 27.8 ± 6.5 no/mm2 | 27.2 ± 13.2 no/mm2 | 7.5 ± 1.1 mm/mm2 | Sample size |
| Rosenberg56 | 23 | 46 ± 8.3 | TSCM | Section/2 images | 3.1 ± 1.2 no/frame | — | — | Type of IVCCM |
a
LSCM, laser-scanning confocal microscope; SSCM, slit-scanning confocal microscope; TSCM, tandem-scanning confocal microscope