Innovative intra-corneal ring-supported graft surgery for treatment of keratoconus and cornea regeneration: Surgical technique and case report

Therapeutic options for corneal ectasia are evolving, with emphasis on the intra-stromal corneal ring for delaying or eliminating the need for penetrating keratoplasty. A 33-year-old man with grade 4 keratoconus and rising intolerance of the hard contact lens underwent a combination of a new innovative ring and graft with suture in the left eye. Excellent structural support and stability of the cornea were observed immediately post-operatively and 12 months after surgery. It appears as a feasible and safe therapy option for keratoconus eyes with reference to the instability and asymmetry of the cornea. Hence, as a safe and effective technique, it can be performed easily.

Evaluation of choroidal thickness and retinal nerve fiber layer thickness in patients with unilateral amblyopia: a prospective study / Avaliação da espessura da coroide e da camada de fibras nervosas da retina em pacientes com ambliopia unilateral: um estudo prospectivo

ABSTRACT Purpose: to compare the Subfoveal choroidal thickness (SFCT) and Retinal Nerve Fiber Layer Thickness (RNFL) of amblyopic and normal fellow eyes. Design: Prospective, cross-sectional, observational case series. Methods: Forty patients age 12 to 41 years (mean 23.73 ± 6.42) with unilateral amblyopia were studied. Among them, 11(28.2%) patients had amblyopia secondary to strabismus and 29(71.8 %) had anisometropic amblyopia. Optical coherence tomography (OCT) of the peripapillary RNFL thickness of amblyopic and fellow eyes was performed. RNFL thickness measurements were taken from the superior, inferior, nasal and temporal quadrants in the peripapillary region. Also, subfoveal choroidal thickness (SFCT) was measured using spectral domain optical coherence tomography (SD-OCT). Results: Mean global RNFL thickness of the amblyopic and fellow eyes was 104.48 microns and 102.83 microns, respectively. The difference between the two groups was not statistically significant (p>0.05%). The thicknesses of the superior, inferior, nasal and temporal quadrants of the retinal nerve fiber layer between the amblyopic and normal fellow eyes showed no statistically significant difference (p>0.05%). However, the SFCT of amblyopic eye was 11 or more microns thicker than the fellow eye and this was statistically significant different (p<0.05%). Conclusions: This study demonstrated SFCT in amblyopic eyes was significantly thicker than the normal fellow eyes. The amblyopic process may involve the choroid, but not the prepapillary NFL.

RESUMO Objetivo: comparar a espessura da coroide subfoveal (CSF) e da camada de fibra nervosa retinal (CFNR) de olhos amblíopes e normais. Design: série de casos prospectivos, transversais e observacionais. Métodos: Quarenta pacientes com idade entre 12 e 41 anos (média 23,73 ± 6,42) com ambliopia unilateral foram estudados. Entre eles, 11 (28,2%) pacientes apresentavam ambliopia secundária a estrabismo e 29 (71,8%) apresentavam ambliopia anisometrópica. Foi realizada tomografia de coerência óptica (TCO) da espessura da CFNR peripapilar do olho amblíope e do outro olho. As medidas de espessura da CFNR foram realizadas nos quadrantes superior, inferior, nasal e temporal na região peripapilar. Além disso, a espessura da coroide subfoveal (CSF) foi medida através de tomografia de coerência óptica de domínio espectral (TCO-DE). Resultados: A espessura média global da CFNR do olho amblíope e do outro olho foi de 104,48 mícrons e 102,83 mícrons, respectivamente. A diferença entre os dois grupos não foi estatisticamente significativa (p > 0,05%). As espessuras dos quadrantes superior, inferior, nasal e temporal da camada de fibras nervosas da retina entre o olho amblíope e o normal não apresentaram diferença estatisticamente significativa (p > 0,05%). No entanto, a CSF do olho amblíope foi 11 mícrons mais espessa (ou mais) do que a do outro olho - essa diferença foi estatisticamente significativa (p < 0,05%). Conclusões: Este estudo demonstrou que a CSF dos olhos amblíopes foi significativamente mais espessa do que a dos olhos normais. O processo amblíope pode envolver a coroide, mas ele não envolve a CFNR peripapilar.

Evaluating the association of VSX1 mutation with keratoconus and the granular corneal dystrophy in an Iranian family / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To evaluate association between mutations in the visual system homeobox 1 (VSX1) gene and keratoconus (KCN) complicated with granular corneal dystrophy (GCD), direct sequencing was performed in an Iranian family affected by KCN and GCD in four generations.METHODS: An Iranian pedigree with keratoconus spanning four generations along with GCD was identified.Whole blood sample was used for genomic DNA extraction.The molecular analysis by using polymerase chain reaction (PCR) of the entire coding region and intron-exon boundaries of VSX1 gene was preformed to investigate the possible linkage between KCN and GCD.Subsequently, direct sequencing was used for PCR products and mutation analysis was conducted in the patients and controls.RESULTS: Mutation analysis in VSX1 gene did not detect evidence for association between KCN and GCD diseases and VSX1 gene.Our data excluded VSX1 as the disease-causing gene for KCN/GCD in this specific pedigree.CONCLUSION: Despite of no association between KCN patients with GCD and VSX1 gene variations, other probable genes involved in pathogenesis of the KCN and GCD diseases need to be investigated in the patients.

Comparison of preoperative and postoperative intraocular lens power values in eyes with Keraring implantation / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To evaluate intraocular lens power (IOL) calculation and biometry before and 3mo after implantation of Keraring 355° intrastromal corneal ring segment (ICRS;Mediphacos, Belo Horizonte, Brazil) in keratoconic eyes.METHODS: In this cohort study, data of 19 keratoconus eyes of 18 patients which undergone ICRS implantations were gathered before and 3mo after surgery.Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), manifest refraction, IOL power calculation formulas, axial lenght (AL) and keratometry were analayzed.RESULTS: Mean age of participants was 29.58±0.6.UCVA improved from 0.84 (0.35) logMAR to 0.43 (0.31) logMAR significantly (P<0.001).BCVA and AL didn`t change significantly after 3mo.All Sphere, cylinder and spherical equivalent (SE) were improved significantly (P<0.001).On the other hand, keratometry 1 (K1) and keratometry 2 (K2) decreased significantly.It was a considerable change in SRK/Ⅱ (P<0.001), Hoffer Q (P<0.001) and Holladay Ⅰ(P<0.001) after 3-month`s follow-up.Among this formula SRK/II had the lowest change.CONCLUSION: In addition to improvement in visual, refractive, and keratometry outcomes after Keraring implantation, there was a significantly changes in IOL calculation formulas values.However, ICRS procedure doesn`t interfere considerably AL in eyes, but it seems reduced keratometric values lead to IOL power calculations more accurately and all formulas suggested same IOL power.

Isolation, culture, characterization and optimization of human corneal stem cells

The effects of human versus mouse EGF on cell growth and culture duration were studied to optimize a human limbal stem cells culture method for therapeutical autologous transplantation. Limbal cells were obtained by trypsin digestion and transferred to a culture medium. The time needed to reach full confluence in culture was determined. Specific antibodies to corneal stem cell marker (P63) versus corneal epithelial differentiation marker (K3) were used for histochemical determinations. A high proportion of P63 positive cells (85 +/- 4.6%), and a correspondingly low proportion K3 positive cells (15 +/- 3.8%) indicated that most cultured cells remained undifferentiated and were considered as stem cells (mean +/- SE, n=10). Cultures reached full confluency after 17.3 +/- 1.2 days when the medium was supplemented with human EGF, while 21.7 +/- 1.5 days were needed when the medium was supplemented with mouse EGF. The results showed that limbal stem cells proliferate more easily and reach to full confluency in a shorter time if the medium is supplemented with hEGF rather than with mEGF.