Table 24: Impact of CXL on Critical Ocular Structures^*.

Author, Year	Patients	Ocular Structure	Findings
Henriquez M, 2011 (44)	10	Macular thickness	By optical coherence tomography - decreased thickness compared to baseline (216 µm) at 1, 3, 6 and 12-months 191 µm, 191µm, 198 µm and 200 µm
Grewel D, 2009 (97)	102	Lens density	By Scheimpflug imaging - no change in lens density (8.7 µm to 8.7 µm]
		Retinal nerve fiber layer	By Scheimpflug imaging - no change in retinal nerve fiber layer (101 µm to 103 µm)
		Foveal thickness	By Scheimpflug imaging - decreased foveal thickness NS -change from baseline to 12-months 175.7 ± 35.6 µm to 146.4 ± 8.5 µm
Knappe S, 2011 (104)	8	Junction region between Bowman’s membrane and the sub-basal nerve plexus	By confocal microscopy the preoperatively tortuous and branched nerve fiber pattern of the sub-basal nerve plexus typical of KC could not be visualized in the central cornea immediately postoperatively and at 3-months postoperatively. At 4 months, the sub-basal nerve fibers again became visible on confocal microscopy.
Kymionis G, 2009 (90)	10	Subepithelial nerve plexus	By confocal microscopy– subepithelial nerve plexus absent at 1 month and regenerated between 3 to 6 months
Mazzotta C, 2006 (105)	10	Subepithelial stromal nerve fibers	By confocal microscopy – normal regeneration and morphological structure of corneal epithelium after 5 days, complete absence of nerve fibers 15 to 30 days post with regeneration continuing and restoring corneal sensitivity after 6 months. No evidence of altered corneal transparency.
Mazzotta C, 2008 (92)	40	Limbus	By confocal microscopy- no damage to the limbal region
		Epithelial nerve plexus	By confocal microscopy, disappearance of subepithelial plexus and anterior-midstromal nerve fibers, restored around 6 months
		Epithelial layer	By confocal microscopy, epithelial regrowth completed after 4 days

^*KC indicates keratoconus; NS, not significant