PURPOSE\nThe safety and efficacy of corneal collagen cross-linking (CXL) and topography-guided photorefractive keratectomy (PRK) using a different sequence and timing were evaluated in consecutive keratoconus cases.\n\n\nMETHODS\nThis study included a total of 325 eyes with keratoconus. Eyes were divided into two groups. The first group (n=127 eyes) underwent CXL with subsequent topography-guided PRK performed 6 months later (sequential group) and the second group (n=198 eyes) underwent CXL and PRK in a combined procedure on the same day (simultaneous group). Statistical differences were examined for pre- to postoperative changes in uncorrected (UCVA, logMAR) and best-spectacle-corrected visual acuity (BSCVA, logMAR), manifest refraction spherical equivalent (MRSE), keratometry (K), topography, central corneal thickness, endothelial cell count, corneal haze, and ectatic progression. Mean follow-up was 36+/-18 months (range: 24 to 68 months).\n\n\nRESULTS\nAt last follow-up in the sequential group, the mean UCVA improved from 0.9+/-0.3 logMAR to 0.49+/-0.25 logMAR, and mean BSCVA from 0.41+/-0.25 logMAR to 0.16+/-0.22 logMAR. Mean reduction in spherical equivalent refraction was 2.50+/-1.20 diopters (D), mean haze score was 1.2+/-0.5, and mean reduction in K was 2.75+/-1.30 D. In the simultaneous group, mean UCVA improved from 0.96+/-0.2 logMAR to 0.3+/-0.2 logMAR, and mean BSCVA from 0.39+/-0.3 logMAR to 0.11+/-0.16 logMAR. Mean reduction in spherical equivalent refraction was 3.20+/-1.40 D, mean haze score was 0.5+/-0.3, and mean reduction in K was 3.50+/-1.3 D. Endothelial cell count preoperatively and at last follow-up was unchanged (P<.05) in both groups. Statistically, the simultaneous group did better (P<.05) in all fields evaluated, with improvement in UCVA and BSCVA, a greater mean reduction in spherical equivalent refraction and keratometry, and less corneal haze.\n\n\nCONCLUSIONS\nSame-day simultaneous topography-guided PRK and CXL appears to be superior to sequential CXL with later PRK in the visual rehabilitation of progressing keratoconus.

Long Term Comparison of Sequential vs. Same-Day Simultaneous Collagen Cross-Linking and Topography-Guided PRK for Treatment of Keratoconus

Major review: Molecular genetics of primary open-angle glaucoma.

Objectif: Determiner les modifications du debit sanguin dans la choroide et la retine chez les sujets atteints de retinopathie myopique. Conception: Etude cas-controles. Contexte: Service d'ophtalmologie d'un centre hospitalier universitaire a Elazig, en Turquie. Sujets: Vingt-et-un patients consecutifs (40 yeux) atteints de myopie degenerative et vingt sujets volontaires (38 yeux) d'âges correspondants, emmetropes et en sante. Aucun des sujets, dans l'un et l'autre groupes, ne souffrait d'une maladie generale, comme le diabete sucre ou l'hypertension, qui aurait pu influer sur la micro- ou la macrocirculation. Mesures des resultats: Vitesse moyenne du debit sanguin, vitesse de pointe en diastole, vitesse de pointe en systole a l'artere ciliaire posterieure et a l'artere retinienne centrale (mesurees au moyen de l'echographie Doppler couleur), indice de pulsatilite et indice de resistance. Resultats: Les valeurs moyennes de la vitesse de pointe de l'ecoulement systolique (12,34 vs 16,90 cm/s) et diastolique (3,12 vs 5.10 cm/s) a l'artere ciliaire posterieure etaient significativement plus basses dans le groupe d'etude que dans le groupe temoin (p < 0,001). Il y avait une difference significative entre les deux groupes au niveau de l'indice de resistance de l'artere ciliaire posterieure (0,74 vs 0,69) (p < 0,05). Les valeurs moyennes de la vitesse de pointe de l'ecoulement systolique (6,64 vs 9,72 cm/s) et diastolique (2,01 vs 3,07 cm/s) a l'artere retinienne centrale etaient significativement plus basses dans le groupe d'etude que dans le groupe temoin (p < 0,001). Conclusion: Le debit sanguin dans la choroide et dans la retine diminue chez les sujets atteints de myopie degenerative. Cette diminution au niveau de la choroide peut etre attribuable en partie a une augmentation de la resistance vasculaire. Au niveau de la retine, il s'agit probablement d'une adaptation.

Choroidal and retinal blood flow changes in degenerative myopia

Background: To investigate the association between corneal biomechanics and optic nerve head morphology in newly diagnosed primary open-angle glaucoma patients.



Design:  Hospital based prospective study.



Participants:  Forty-two untreated newly diagnosed primary open-angle glaucoma patients.



Methods:  Patients underwent corneal hysteresis measurement using the Ocular Response Analyzer and confocal scanning laser ophthalmoscopy for optic nerve head topography evaluation. One eye was selected randomly for analysis. Data collected included age, race, gender, intraocular pressure and central corneal thickness.



Main Outcome Measures:  Multiple regression analysis (controlling for baseline intraocular pressure and disc area) was used to investigate factors associated with the following optic nerve head topographic parameters: linear cup-to-disc ratio and mean cup depth.



Results:  Mean age of participants was 66.7 ± 11.8 years. Corneal hysteresis was the only factor significantly associated with both mean cup depth (correlation coefficient [r] = −0.34, P = 0.03) and cup-to-disc ratio (r = −0.41, P = 0.01). Central corneal thickness was significantly associated with mean cup depth (r = −0.35, P = 0.02), but not with cup-to-disc ratio (r = −0.25, P = 0.13). Although a trend towards a positive association between age and cup-to-disc ratio was identified (r = 0.26, P = 0.08), age was not significantly associated with mean cup depth (r = 0.06, P = 0.72). When comparing fellow eyes of patients with bilateral glaucoma, the eye with higher corneal hysteresis had smaller cup-to-disc ratio in 75% of the cases.



Conclusions:  In untreated newly diagnosed primary open-angle glaucoma patients, those with thinner corneas and mainly lower corneal hysteresis values had a larger cup-to-disc ratio and deeper cup, independently of intraocular pressure values and disc size.

Association between corneal biomechanical properties and optic nerve head morphology in newly diagnosed glaucoma patients

Primary congenital glaucoma: An updated review.

Purpose : To evaluate whether changes in optic nerve head topography and visual field in patients with primary open-angle (POAG) are related to central corneal thickness (CCT). Materials and Methods : Eighty eyes of 50 patients with POAG underwent ophthalmic examination; optic nerve head imaging with the Heidelberg Retina Tomography II (HRT II), ultrasound corneal pachymetry, and visual field evaluation with the Humphrey visual field analyser (program 24-2). Correlation between CCT, age, gender, family history of glaucoma, visual acuity, intraocular pressure (IOP), optic disc surface area, vertical and horizontal cup: disc ratios, neuroretinal rim area, mean deviation of visual field, and number of glaucoma medications was analyzed. Patients were divided into a thin CCT group 540 μm. Pearson correlation was used for correlation coefficient and a P value of Results : Thin CCT was significantly correlated with vertical and horizontal cup: disc ratios, neuroretinal rim area loss, and smaller optic disc surface area (r=0.043, r=0.021, r=0.036, and 0.031 respectively). Thin CCT was also significantly associated with worsened mean deviation of visual field, and increased number of glaucoma medications (r=0.065 and r=0.423). Patients with positive family history correlated with with greater vertical cup: disc ratio, and more glaucoma medications but this was not statistically significant. Conclusions : In patients with POAG those with thinner CCT are likely to develop greater glaucomatous optic nerve and visual field damages than those with a thicker CCT.

Correlation of central corneal thickness and optic nerve head topography in patients with primary open-angle glaucoma

Purpose:To evaluate the intermediate-term efficacy and safety of micropulsed diode laser cyclophotocoagulation in recurrent pediatric glaucoma.Patients and Methods:A prospective interventional stud...

Micropulsed diode laser cyclophotocoagulation in recurrent pediatric glaucoma.

AIM To evaluate the safety and the efficacy of the ultrasound ciliary plasty (UCP) on the intraocular pressure (IOP) control in glaucomatous eyes without previous glaucoma surgery. METHODS A retrospective study included patients with primary and secondary glaucoma who underwent UCP in Dar AlShifa Hospital, Kuwait between January 2017 to June 2018. High-intensity focused ultrasound procedures were performed under peribulbar anesthesia using the 2nd generation probe with 8s duration of each of the 6 shots. Complete ophthalmologic examinations were scheduled pre-treatment, and at 1d, 1wk, 1, 3, 6 and 12mo post-treatment. Primary outcomes were the IOP reduction and success rates at 12mo, while the secondary outcomes were the occurrence of vision threatening complications and visual acuity. RESULTS The records of 62 eyes of 62 patients were analyzed with mean age of 63.8y (67.7% males). There was statistically significant reduction in the mean IOP from 35.2±8.3 mm Hg before treatment to 20.6±8.7 mm Hg at 12th month (P<0.0005) with a mean percentage IOP reduction of 42.3% with significant reduction in the mean number of antiglaucomatous drugs from 3.2±0.4 before treatment to 2.1±1.02 at 12mo (P<0.0005). Qualified success was achieved in 77.4% of eyes at 12mo. No major intra- or post-treatment complications were reported. CONCLUSION Second-generation UCP prove to be effective in reducing IOP in naive glaucoma patients with lower success rates in cases of neovascular and uveitic glaucomas.

Safety and efficacy of ultrasound ciliary plasty as a primary intervention in glaucoma patients.

AIM To analyze childhood glaucoma regarding its demographics, presentations, different causes and surgical modalities used among patients in Dakahelia and to apply the Childhood Glaucoma Research Network (CGRN) classification retrospectively to evaluate its convenience. METHODS A retrospective study in which the medical files of all glaucoma patients <16 years old presented to Mansoura Ophthalmic Center, Mansoura University from 2014 to 2017, were retrieved and analyzed. Collected data included: age, gender, laterality, visual acuity (VA), refraction, intraocular pressure (IOP), corneal diameter, cup-disc ratio, types and number of surgeries and antiglaucomatous drugs (AGD) at the first and last visit. Prevalence of different subtypes was calculated and means of clinical features were compared. RESULTS A total of 305 eyes of 207 patients were included classified into 6 groups: primary congenital glaucoma (PCG), juvenile open angle glaucoma (JOAG), glaucoma associated with systemic disease, glaucoma associated with ocular anomalies, acquired glaucoma and glaucoma following cataract surgery. PCG was the predominant type (55.1%) followed by acquired glaucoma (29.5%). Males represented 63.8% of the whole studied patients. Glaucoma associated with ocular anomaly group showed the youngest age at diagnosis (21.9±30.0mo). The shortest corneal diameter was recorded in post cataract group (10.4±0.5 mm). Highest cup-disc ratio was found in the PCG group (P<0.0005). Glaucoma associated with systemic disease presented with the highest baseline IOP (34.5±5.0 mm Hg). All the cases with PCG were treated surgically with 21.8% required more than one surgery. The majority of the patients (74.2%) in the acquired group were treated medically. Combined trabeculotomy-trabeculectomy was the most frequent operation done, accounting for 34.5% of all primary surgeries. Ahmed valve implantation comprised 87% of the secondary surgeries. Acquired glaucoma group had the highest percent of eyes with good final Snellen's VA (69.4%), while glaucoma associated with ocular anomaly group had poorest final VA. CONCLUSION PCG is the most prevalent type of childhood glaucoma, followed by acquired glaucoma especially traumatic hyphema. Combined trabeculotomy-trabeculectomy and Ahmed valve implantation are the most common surgical interventions. CGRN classification is found to provide a consensus skeleton and is recommended to be integrated in our routine ongoing clinical practice.

Childhood glaucoma profile in Dakahelia, Egypt: a retrospective study.

Purpose: To evaluate the color Doppler imaging (CDI) and pattern visual evoked potential (P-VEP) examinations in primary open angle glaucoma (POAG) patients investigate the relation between flow velocities measured by CDI and P-VEP examination in POAG patients. Methods: Sixty five POAG patients and 45 control subjects underwent CDI evaluation of the ophthalmic artery (OA), short posterior ciliary artery (SPCA) and central retinal arteries (CRA). The peak systolic velocities (PSV) and end-diastolic velocities (EDV) and resistive index (RI) of all retrobulbar vessels were measured. The latency and amplitude of P100 in P-VEP were recorded. The differences of CDI and P-VEP parameters among POAG and control groups were compared. The correlations between CDI parameters, visual field indices and P-VEP in POAG patients were evaluated by Pearson’s correlation analysis. Results: POAG patients had the lower EDV and higher RI in the OA, CRA and SPCA comparing with that of control subjects. Also, POAG patients had lower PSV in OA and CRA comparing with that of control subjects. The latency of P100 in VEP delayed and the amplitude of P100 decreased in the POAG patients comparing with that of the control group. The RI of OA and SPCA were negatively correlated with the mean deviation (MD) values in the POAG patients. The RI of OA was positively correlated with the PSD value in POAG patients. The MD values in POAG patients were negatively correlated with the latency time of P100. The RI of OA was positively correlated with the latency time of P100 and negatively correlated with the amplitude of P100 in the POAG patients. Conclusions: The combination of the CDI and pattern VEP techniques provides further interpretation of ocular circulatory changes in POAG patients. Further studies are needed for assessment the relationship between circulatory and neural changes.

https://www.longdom.org/open-access/imaging-and-pattern-visual-evoked-potential-in-primary-open-angle-glaucoma-2155-9570.1000127.pdf

Tharwat H Mokbel

Papers

Correlation of central corneal thickness and optic nerve head topography in patients with primary open-angle glaucoma

Micropulsed diode laser cyclophotocoagulation in recurrent pediatric glaucoma.

Safety and efficacy of ultrasound ciliary plasty as a primary intervention in glaucoma patients.

Childhood glaucoma profile in Dakahelia, Egypt: a retrospective study.

Diagnostic Value of Color Doppler Imaging and Pattern Visual Evoked Potential in Primary Open-Angle Glaucoma