Ex vivo Confocal Microscopy of Human Corneal Nerves

Mouhamed Al-Aqaba (1) , Thaer S Alomar (1) , Ammar Miri (1) , Usama Fares (1) , Ahmad Muneer Otri (1) , Harminder Singh Dua (2)

1 UON - University of Nottingham, UK
2 University Hospital

Aims: To evaluate the distribution, morphometry and the post-mortem changes of the central and peripheral human corneal nerves by ex-vivo laser-scanning confocal microscopy (EVCM). Methods: 24 eyes from 14 cadavers were retrieved at different time intervals after death and examined by EVCM. Five regions were examined in each eye namely central, superior, inferior, temporal and nasal. In each region, corneal nerve images were categorized according to their anatomical location in the cornea into sub-basal, stromal and limbal nerves. Five nerve parameters were measured; density, orientation, diameter, numbers and branching pattern. Results: Ex-vivo confocal scanning of a motionless eye allows high quality imaging and tracking of corneal and limbal nerves. Stromal nerves from the sub-Bowman's plexus perforate the Bowman's zone and terminate in blub like structures, from each of which a leash of sub-basal nerves arise. Following death, sub-basal nerve parameters showed significant changes. The density decreased from 9.23±4.48 to 0.45±0.07 mm/mm2; the diameter from 4.01±0.81 to 2.08±0.20 ìm; the numbers from 8.3 to 1.0 and branching pattern from 39.38% to 0% (p<0.05) from day one to day five post-mortem. Stromal and limbal nerves showed no significant changes in their density and diameter. Conclusions: This study establishes a direct link between sub-basal nerves and the sub-Bowmans nerves via distinct terminal bulbs. Limbal nerves are the thickest, are seen in all quadrants and can be traced to the corneal centre. The sub-basal nerve plexus rapidly degenerates after death but stromal and limbal nerves survive during the first five days after death.

Mots clés: Cornea; Anatomy; Imaging

Mouhamed Al-Aqaba, Thaer S Alomar, Ammar Miri, Usama Fares, Ahmad Muneer Otri, et al.. Ex vivo Confocal Microscopy of Human Corneal Nerves. British Journal of Ophthalmology, 2010, 94 (9), pp.1251. ⟨10.1136/bjo.2009.178244⟩. ⟨hal-00557363⟩