RESUMEN
AIM: To evaluate the efficacy of recombinant human nerve growth factor-loaded amniotic membrane (rhNGF-AM) on corneal epithelial and nerve regeneration in rabbit model. METHODS: Freshly prepared human amniotic membrane (AM) were immersed into PBS buffer containing 100 or 500 µg/mL rhNGF for 15, 30, and 60min at 4°C. The in vitro release kinetics of rhNGF was measured with ELISA. For in vivo evaluation, the AM were immersed with 500 µg/mL rhNGF for 30min. Fifty-seven rabbits were selected to establish corneal epithelial defect model. In addition to the 19 rabbits in control group, 38 rabbits received AM transplantation with or without rhNGF after the removal of central epithelium. Corneal epithelial defect area, sub-epithelial nerve fiber density, corneal sensitivity, rhNGF contents in resident AM and corneas were measured after the surgery. RESULTS: rhNGF was sustained release from the AM within 14d in vitro, with the positive correlation with initial immersion concentration. The immersion of AM in 500 µg/mL rhNGF for 30min achieved the most stable release within 14d. After transplantation in rabbit cornea, a high concentration of rhNGF in resident rhNGF-AM and cornea was maintained within 8d. Corneal epithelial healing, nerve fiber regeneration and the recovery of corneal sensitivity were significantly accelerated after the rhNGF-AM transplantation when compared to simple AM transplantation (all P<0.05). CONCLUSION: Simple immersion of AM achieves the sustained release of rhNGF, and promotes corneal epithelial wound healing and nerve regeneration, as well as the recovery of corneal sensitivity in rabbit.
RESUMEN
AIM: To investigate the therapeutic effects of simultaneous horizontal and vertical operations on dissociated vertical deviation (DVD) associated with other deviations. METHODS: Forty-five cases of DVD with horizontal and torsional strabismus underwent combined operation were collected retrospectively. All clinical records were analyzed. All patients were followed up for 6 to 24mo. Wilcoxon signed-ranks test was performed to evaluate the changes of vertical and horizontal deviation. χ 2 test was used to evaluate the changes of binocular visual function. RESULTS: Forty-five cases included 36 patients with intermittent exotropia and binocular inferior oblique overaction (IOOA), 5 patients with concomitant esotropia and binocular IOOA, 4 patients with intermittent exotropia and monocular superior oblique palsy. The superior rectus recession (SRR) combined with horizontal rectus recession and the myectomy of inferior oblique or anterior transposition were operated simultaneously to correct all types of strabismus. There were 43 cases who achieved normal eye position in vertical direction, while 2 cases were with undercorrection of 5Δ to 6Δ. In patients with horizontal strabismus, 2 cases of exotropia were with overcorrection of 6Δ to 8Δ, 1 case of esotropia was with undercorrection of 6Δ, and 1 case of monocular superior oblique palsy with compensatory head posture was not significantly improved. The binocular visual function of most patients recovered after operation. The difference of the binocular visual function and eye position were significant compared with that before operation (P<0.05). CONCLUSION: The simultaneous operation on DVD with horizontal and torsional strabismus is successful.
