OBJECTIVE: The goal of this study was to develop a novel pupil and iris segmentation algorithm. We evaluated segmentation performance based on a fractal model. Two methods were compared: Daugman's and our new proposed method. METHODS: We received 200 anterior segment images with 3,872x2,592 pixels. Here we present an active contour model that accurately detects pupil boundaries in order to improve the performance of segmentation systems. We propose a method that uses iris segmentation based on a fractal model. We compared the performance of Daugman's method and the proposed new method and statistically analyzed the results. RESULTS: We manually compared segmentation with the Daugman's method and the new proposed method. The findings showed that the proposed segmentation accuracy was about 2.5 percent higher than Daugman's method. There was a significant difference (p<0.05) between the under and over data between the two methods. CONCLUSION: The results of this study show that the new proposed method was more accurate than the conventional method for the measurement of segmentation of the eye by CAD (Computer-aided Diagnosis).
Eye ; Fractals ; Iris ; Pupil

In this report, we want to propose new one-dimensional parameters for eye-image correction through manipulations of lid elevation. The eye ball exposure area could be divided to three subdivisional areas: iris, medial sclera and lateral sclera. Ratios among these subdivisional square measures of eye ball exposure are the most important and effective factors to present for the eye-image. But, for the surgeons, it is not easy to measure this areas. So we came to propose paramedian widths, mid-scleral widths. We suggest several compositions of one-dimensional measures which would represent for eye-image like the ratios of square measures of subdivisional areas. However, there would be no exact rule in this ratios because there have been no exact rule also in the beautiful face, they would be useful rules for eye-image. It is entirely up to every surgeon to decide the rules of these parameters.
Iris ; Sclera

There are 2 subluxations of Binkhorst 2-loop lens among my 70 cases of intraocular lens implantation during 4 years duration. One Worst Medallion lens that was implanted by American doctor had subluxation 10 months after operation and managed with medical treatment by the author. One of the Binkhorst 2-loop lens was reposited by surgical method and another 2-loop lens was removed due to incomplete constriction of the pupil with vitreous prolapse during surgical manipulation. The two reposited caSeS had good vision but the removed case had very poor vision(20/200) due to Severe corneal endothelial dystrophy.
Constriction ; Iris* ; Lens Implantation, Intraocular ; Lenses, Intraocular* ; Prolapse ; Pupil

PURPOSE: To describe that Computer image recognition technique is more accurately and less invasive than other methods, which using contact lens with a search probe or electrodes for record of eye movements. METHODS: A reference marker which was infrared was attached to the center of the forehead of the patients and the infrared light was illuminated to both eyes. Video image sequences were recorded using digital CCD camera and the captured image frames (640 X 480) were processed using a image analysis program. From which each image frame captured, pupil area was saperated using difference of brightness in pupil and iris. And then the pupil center was determined by calculating the center-of-mass of black pixels to meet the pupil threshold criteria. RESULTS: In a post-processing process, we could acquire horizontal and vertical eye position and velocity data. Inverse fast fourier transformation(FFT) and digital filtering algorithm were applied to filter out noise due to limited resolution of the CCD camera and sampling rates. Experimental result showed that the system could detect about 0.2mm positional location and 30Hz horizontal and vertical eye movements simultaneously. CONCLUSIONS: We could accurately measure and record two dimensional eye movements of patients (horizontal and vertical simultaneously) in real time with some head movements.
Electrodes ; Eye Movements* ; Forehead ; Head Movements ; Humans ; Iris ; Noise ; Pupil

PURPOSE: To evaluate surgical results of phacoemulsification cataract surgery with respect to pupil size and iris retractors and to compare the effects of iris retractors according to the pupil size. METHODS: This retrospective study included 90 eyes that underwent phacoemulsification cataract surgery. All of the eyes had a maximally dilated pupil size of 7 mm or smaller. RESULTS: When the patients were evaluated according to pupil size, we found no difference in BCVA (best-corrected visual acuity) and phaco power x time between patients who had surgery involving iris retractors and those who did not. However, in patients with pupil sizes 3 mm or smaller, we did observe a statistically significant decrease in endothelial cell density (CD) when the iris retractor was used compared to when the retractor was not used (p<0.05). A comparison of preoperative and postoperative BCVA measurements revealed a significant BCVA increase in eyes with pupils larger than 3 mm. In contrast, in eyes with pupils smaller than 5 mm, significant decreases in CD were found when the preoperative and postoperative measurements were compared. CONCLUSIONS: In this study, we found that the iris retractor is useful for protecting corneal endothelial cells when the pupil size is smaller than 3 mm.
Cataract* ; Endothelial Cells ; Humans ; Iris ; Phacoemulsification* ; Pupil* ; Retrospective Studies

The aim of this study was to evaluate the effect of cavity shape, bond quality of bonding agent and volume of resin composite on shrinkage stress developed at the cavity floor. This was done by measuring the shear bond strength with respect to iris materials (cavity shape; adhesive-coated dentin as a high C-factor and Teflon-coated metal as a low C-factor), bonding agents (bond quality; Scotchbond(TM) Multi-purpose and Xeno(R)III) and iris hole diameters (volume; 1 mm or 3 mm in diameter x 1.5 mm in thickness). Ninety-six molars were randomly divided into 8 groups (2 x 2 x 2 experimental setup). In order to simulate a Class I cavity, shear bond strength was measured on the flat occlusal dentin surface with irises. The iris hole was filled with Z250 restorative resin composite in a bulk-filling manner. The data was analyzed using three-way ANOVA and the Tukey test. Fracture mode analysis was also done. When the cavity had high C-factor, good bond quality and large volume, the bond strength decreased significantly. The volume of resin composite restricted within the well-bonded cavity walls is also be suggested to be included in the concept of C-factor, as well as the cavity shape and bond quality. Since the bond quality and volume can exaggerate the effect of cavity shape on the shrinkage stress developed at the resin-dentin bond, resin composites must be filled in a method, which minimizes the volume that can increase the C-factor.
Dentin* ; Iris ; Molar

The objectiveness of this study was to evaluate whether low-viscosity composite can bond effectively to dentin surface without bonding resin. The low-viscosity composites being 50wt% filler content were made by the inclusion of bonding resin of two self-etching systems(Clearfil SE Bond, Unifil Bond) varied with contents as 0, 10, 20, 30, 40, 50wt%. Exposed dentin surfaces of extracted 3rd molars are used. Dentin bond strengths were measured. The tests were carried out with a micro-shear device placed testing machine at a CHS of 1mm/min after a low-viscosity composite was filled into an iris cut from micro tygon tubing with internal diameter approximately 0.8mm and height of 1.0mm. 1. Flexural strength and modulus was increased with the addition of bonding resin. 2. Micro-shear bond strength to dentin was improved according to content of bonding resin irrespective of applying or not bonding resin in bonding procedure, and that of Clearfil SE Bond groups was higher than Unifil Bond. 3. There were no significant difference whether use of each bonding resin in bonding procedure for S-40, S-50, U-50(p>0.05). 4. In SEM examination, resin was well infiltrated into dentin after primed with self-etching primer only for S-50 and U-50 in spite of the formation of thinner hybrid layer. Low viscosity composite including some functional monomer may be used as dentin bonding resin without an intermediary bonding agent. It makes a simplified bonding procedure and foresees the possibility of self-adhesive restorative material.
Dentin* ; Iris ; Molar ; Viscosity

This study was performed to evaluate histopathologic and physical characteristics of anterior capsule during capsulorhexis with a new high-frequency diathermy.The authors investigated the histopathologic characteristics of anterior capsule according to coagulation time and anterior capsular diameter in diathermy capsulorhesxis(DC),comparing with those in continuous curvilinear capsulorhexis(CCC). Thermally induced histopathologic alter-ation was localized at anterior capsule with coagulation for 0.5 second, while it was extended into cortex with coagulation for 2 seconds.When capsulorhexis was performed with diameter of 6 mmand the margin was pulled with iris retractor,anterior capsular edge was fully extended both in CCC and DC.But with diameter of 3.5 mm,DC mostly led to tear of capsular edge on its extension,while CCC permitted full extension of anterior capsular edge.These results suggest that strength of anterior capsular edge in DC is inferior to that in CCC.However diathermy capsulorhexis is a useful alternative technique in cases,which CCC is difficult to perform,such ashypermature or congenital cataracts.
Capsulorhexis* ; Cataract ; Diathermy* ; Iris

Polycoria is a rare congenital anomaly of iris. In a wider sense polycoria is including iris dehiscence and iris diastasis as well as true polycoria. A case of binocular iris dehiscence accompanied with congenital anomalies of teeth was reported and literatures were reviewed.
Iris ; Telescopes* ; Tooth

Rieger's anomaly refers to a dysgenesis that features bilateral hypoplasia of the iris stroma, posterior embryotoxon and the associated angle anomalies, pupillary distortion, polycoria, and a high likelihood of glaucoma. In addition to glaucoma, other defects, usually dental, may be present in Rieger's anomaly. When glaucoma occurs, it usually develops during the first to third decades but infrequently occurs in infancy. Frequently mesodermal dysgenesis accompanies ectopia of the pupil and polycoria. In these anomalies no new synechias are formed such as occur in essential iris atrophy. Cataracts are occasionally part of the picture. The anomaly is extremely variable in its expression with the full-blown disease in one member of a family and only minimun signs in another. The authors experienced a case of Rieger's anomaly which occurred in both eyes of 18 year old male who had above characteristic ocular findings and associated juvenile onset glaucoma.
Adolescent ; Atrophy ; Cataract ; Glaucoma ; Humans ; Iris ; Male ; Mesoderm ; Pupil ; Pupil Disorders