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Maged M Roshdy,1,2 Sherine S Wahba,1,2 Ramy R Fikry2,3 1Ophthalmology Department, Ain Shams University, Cairo, Egypt; 2Ophthalmology Department, Al Watany Eye Hospital, Cairo, Egypt; 3Ophthalmology Department, Cairo University, Cairo, Egypt Purpose: The aim of this study was to find indices for keratoconus (KC) detection with higher sensitivity and specificity than the currently available ones with the rotating Scheimpflug imaging (Oculyzer I, Pentacam) software.Patients and methods: Data of 103 normal and 73 KC eyes imaged by Oculyzer I, including slit-lamp examination, refraction, Scheimpflug images, and follow-up data were collected. Logistic regression was done to find new indices with higher area under receiver operating characteristic curves using the currently available ones.Results: The Corneal Assessment Index from Relational thickness and other OCULUS Values 9 (CAIRO 9) index, deduced from the Ambrosio relational thickness-maximum and the anterior elevation at thinnest point from 9 mm best-fit sphere, and the CAIRO 8, deduced from Ambrosio relational thickness-maximum and anterior elevation at thinnest point from 8 mm best-fit sphere, have a very high area under receiver operating characteristic curves for KC detection (0.997 and 0.995, respectively).Conclusion: New corneal assessment index is deduced with better sensitivity and specificity for KC detection. Keywords: keratoconus, pentacam, keratoconus indices, elevation, pachymetry, keratoconus diagnosis

Mohamed M Mahgoub,1,2 Maged M Roshdy,1,2 Sherine S Wahba1,2 1Ophthalmology Department, Ain Shams University, 2Ophthalmology Department, Al Watany Eye Hospital, Cairo, Egypt Purpose: To study the subconjunctival silicone oil (SCSO) parameters associated with dellen formation following microincision vitrectomy (MIV).Patients and methods: This was a case–control study of 20 eyes with SCSO following MIV. Ten of them suffered postoperative dellen formation. Dellen occurrence, their sizes, number of loci, and distance between SCSO and the limbus were recorded. The outcome after silicone-oil removal was evaluated.Results: The SCSO was at 3.1±1.2 mm from the limbus. All cases with dellen had SCSO within 2 mm of the limbus (P<0.001). No other factors were found to be associated with dellen formation (age, P=0.414; sex, P=0.656; laterality, P=1; indication for pars plana vitrectomy, P=0.655; instrument gauge, P=0.211; circumference involved by SCSO, P=0.252). All the dellen healed after surgical evacuation of SCSO (P<0.001), leaving scars.Conclusion: Dellen can be associated with MIV secondary to SCSO near the limbus. Resolution with scarring occurred following SCSO evacuation. Therefore, SCSO should be evacuated as early as possible to avoid long-term peripheral corneal morbidity. Keywords: silicone oil-removal, subconjunctival silicone oil, dellen, vitrectomy

Fathy Fawzy,1,2 Sherine S Wahba,1,3 Nader Fawzy1,4 1Al Watany Eye Hospital, 2Ophthalmology Department, Military Medical Academy, 3Ophthalmology Department, Ain Shams University, Cairo, Egypt; 4Sehkraft Augenzentrum, Cologne, Germany Abstract: We present an observational sign that ensures perfect alignment during femtosecond laser-assisted in situ keratomileusis (FS LASIK). Alignment is assured when a microsponge is used to dry the flap and the area of dryness exceeds the area of direct touch of the microsponge. The area might even reach the whole circumference of the flap at the first touch. This sign of alignment can be explained by microcapillary action. This sign was not elicited in flaps created by a microkeratome. Keywords: capillarity, femtosecond LASIK flap, corneal flap alignment

Amany R Wissa, Sherein S Wahba, Maged M RoshdyAin Shams University and National Eye Hospital, Cairo, EgyptPurpose: To find the relationship between axial length (AL) and anterior chamber depth (ACD) measurements, using partial coherence interferometry (PCI) and A-scan ultrasonography (US).Setting: National Eye Hospital, Cairo, Egypt.Method: Retrieving and comparing biometric data from the files of 163 consecutive patients seeking cataract extraction by PCI (IOLMaster) and US (Sonomed).Results: AL measured using US range from 20.93 to 33.17 mm (mean ± SD = 24.45 ± 2.73 mm). AL measured by PCI range from 20.90 to 33.27 mm (24.05 ± 2.76 mm). The range of ACD measured by US was 2.09 to 4.48 mm (3.32 ± 0.46 mm). The range of ACD measured by PCI was 2.15 to 4.29 mm (3.31 ± 0.45 mm). There is very high agreement between both methods; the intraclass correlation coefficient = 0.999 for AL, and 0.966 for ACD measurements. A linear regression model of two formulae fits the AL values (one for eyes longer than 29 mm, and the other for the shorter eyes), with no significant departure from linearity (P > 0.1). One formula fits the ACD values with significant departure from linearity (P < 0.05).Conclusion: Both US and PCI methods for measurements of AL and ACD are highly correlated. Therefore, the value of AL measured by one method can be predicted, with high accuracy, from the other method.Keywords: axial length, anterior chamber depth, A-scan US, partial coherence interferometry

Sherein S Wahba, Riad F Riad, Fathy F Morkos, Abdallah K Hassouna, Maged M RoshdyNational Eye Hospital and Ain Shams University, Cairo, EgyptSynopsis: The aspheric, one-piece design of the Tecnis® ZCB00 intraocular lens provided higher mesopic contrast sensitivity and relatively constant refraction at different pupil sizes compared to the Sensar® AR40e.Purpose: Comparing the impact on functional vision of the aspheric Tecnis® ZCB00 one-piece lens compared to the spherical Sensar® AR40e three-piece lens.Setting: National Eye Hospital, Cairo, Egypt.Methods: In this prospective study, we implanted 32 Tecnis ZCB00 (Abbott Medical Optics, Santa Ana, CA) and 30 Sensar AR40e (Pharamacia and Upjohn LLC, North Peapack, NJ) lenses. Twenty-three patients in the ZCB00 group and 13 patients in the AR40e group provided reliable, reproducible data, and were therefore included in the statistical analysis. After 8 weeks, we measured photopic contrast sensitivity (PCS) at 85 cd/m² and mesopic contrast sensitivity (MCS) at 5 cd/m². Uncorrected and best-corrected visual acuity were measured. Myopic shift was analyzed by comparing the manifest refraction spherical equivalent at 3 days and 8 weeks after surgery in the normal and dilated pupil.Results: The Tecnis ZCB00 group showed significantly better MCS than the Sensar AR40e group at a spatial frequency of six cycles per degree (cpd) (P = 0.037), but not at 3, 12, or 18 cpd (P = 0.299, P = 0.226, and P = 0.396, respectively). There were no significant differences between groups in corrected distance visual acuity (P = 0.175) or PCS at 3, 6, 12, or 18 cpd spatial frequencies (P = 0.440, P = 0.176, P = 0.365, and P = 0.251, respectively). The ZCB00 group showed less myopic shift in normal and dilated pupils between 3 days and 8 weeks after surgery compared to the AR40e group, but this difference was not significant.Conclusion: The Tecnis one-piece ZCB00 provided higher MCS at moderate spa