Visual restoration with KPro after face allotransplantation with a grade III phthisical eye.

The Boston Keratoprosthesis type I (KPro-I) has been shown to be successful in restoring vision after severe ocular burns; however, its long-term outcomes in phthisical eyes have rarely been reported. A monocular woman with a history of severe alkali chemical injury necessitating facial transplantation presented with a light perception left eye after a complicated course, including failed KPro-I, therapeutic penetrating keratoplasty, endophthalmitis, hypotony, total retinal detachment, and structural changes, including a shrunken 18 mm axial length and eye wall thickening. The patient underwent a combined vitrectomy with silicone oil and KPro-I implantation, resulting in her regaining ambulatory visual acuity (20/250) at 3 years' follow-up.

Effect of topical latanoprost on choroidal thickness and vessel area in Guinea pigs.

The aim of this study was to investigate the effect of latanoprost, an ocular hypotensive agent and prostaglandin analog, on choroidal thickness and structure in young adult guinea pigs. Young (three-month-old) guinea pigs (n = 10) underwent daily monocular treatment with topical 0.005% latanoprost for 2 weeks, followed by a washout period of 2 weeks. Tonometry (iCare) and retinoscopy were undertaken to monitor intraocular pressure (IOP) and refractive error (recorded as spherical equivalent refractive error; SER), respectively. Axial length (AL) and choroidal thickness (ChT) were measured using high frequency A-scan ultrasonography, with additional ChT data, as well as choroidal vessel (ChV) areas obtained from posterior segment imaging using Spectral Domain-Optical Coherence Tomography (SD-OCT). Image J was used to analyze SD-OCT images. As expected, latanoprost significantly reduced IOP in treated eyes. Mean interocular IOP difference (±SE) changed from -0.40 ± 0.31 mmHg at baseline to -2.23 ± 0.43 mmHg after 2 weeks of treatment (p = 0.05). However, SER and AL were unaffected; interocular difference changed from 0.41 ± 0.58 to 0.38 ± 0.43 D and from -0.002 ± 0.02 mm to -0.007 ± 0.01 mm (p > 0.05), respectively. Latanoprost had minimal effect on ChT. Interocular ChT differences were 0.01 ± 0.06 µm at baseline and 0.04 ± 0.06 µm after 2 weeks of treatment (SD-OCT; p > 0.05). However, treated eyes had significant increased ChV areas; interocular differences changed from -0.76 ± 69.2 to 100.78 ± 66.9 µm2 after treatment (p = 0.04). While this study was limited to otherwise untreated young adult guinea pigs, the possibility that choroidal vessel enlargement contributes to the previously reported inhibitory effect of topical latanoprost on myopia progression in young guinea pigs warrants investigation.

Strain-Dependent Differences in Sensitivity to Myopia-Inducing Stimuli in Guinea Pigs and Role of Choroid.

Purpose: To investigate differences in sensitivity to myopia-inducing stimuli of two strains of pigmented guinea pigs. Methods: Eleven-day-old animals (New Zealand [NZ], n = 24 and Elm Hill strains [EH], n = 26) wore either a +2 or -2 diopter (D) lens over one eye and a plano lens over the fellow eye for 5 days; other 10-day-old EH (n = 9) and 7-day-old NZ (n = 9) animals were monocularly form-deprived (FD) for 28 days. Choroidal thickness and axial length were measured using A-scan ultrasonography at baseline and after 1 and 5 days for optical defocus treatments, and at baseline and after 28 days for the FD treatment. Refractive errors were measured by retinoscopy. Choroids of untreated animals were also evaluated using spectral-domain optical coherence tomography. Results: One day of optical defocus induced bidirectional (optical sign-dependent) choroidal responses in EH animals only (P < 0.01). Similar responses were detected in NZ animals after 5 days (P < 0.01), with concordant spherical equivalent refraction changes (P < 0.01). Compared with NZ animals, EH animals developed minimal myopia with FD after 28 days (-4.58 ± 0.97 vs. -0.69 ± 0.75 D for NZ versus EH, P < 0.001). Yet, EH animals showed paradoxical choroidal thickening, 20 ± 9 vs. -8 ± 8 µm for EH versus NZ, P < 0.001. Untreated EH animals also had significantly thicker choroids than NZ animals (147 ± 19 vs. 132 ± 16 µm, P < 0.05), with well-defined layering. Conclusions: As previously reported in chicks, guinea pigs show strain-related differences in response to myopia-inducing stimuli. The finding of a thicker, multilayered choroid in the strain showing decreased sensitivity to FD is provocative, suggesting a possible protective role of the choroid.