PURPOSE: To investigate new diagnostic criteria of keratoconus using Orbscan II Slit Scanning Corneal Topography/Pachymetry System. METHODS: Eighty eyes of 45 patients with keratoconus and 100 randomly selected eyes of 50 patients without any ophthalmologic problem were enrolled in this study. Anterior elevation from BFS, posterior elevation from BFS, Sim K (maximum), and thinnest pachymetric value were evaluated using Orbscan II. Values outside 2 standard deviations from the mean value of each parameter were estimated to the upper or lower limits in diagnosing keratoconus. RESULTS: There were significant differences of all parameters of Orbscan II between the keratoconic eyes and the control (p<0.001). Keratoconus could be diagnosed with 86.3% sensitivity and 99.0% specificity when 3 or more criteria were satisfied and with 96.3% sensitivity and 99.0% specificity when 2 or more criteria were satisfied out of the following 4 criteria; anterior elevation from BFS > 23.3 micro meter, posterior elevation from BFS > 49.8 micro meter, Sim K (maximum) > 47.0 D, thinnest pachymetric value < 455.0 micro meter. CONCLUSIONS: Orbscan II can provide useful information in the diagnosis of keratoconus with high sensitivity and specificity.
Diagnosis ; Humans ; Keratoconus* ; Sensitivity and Specificity

PURPOSE: We collected genomic DNAs of Korean patients with inherited corneal disorders, and identified mutations of the BIGH3 gene related corneal dystrophies in Korean patients: Lattice type I (CDLI), Avellino (ACD), Reis-Buckler's (CDRB). METHODS: Slit-lamp examination of 75 patients and their relatives was carried out to confirm the diagnosis of the disorders. We composed pedigree and extracted genomic DNAs from members of the CDaffected family and individual patients. Genomic DNAs of the patients with mutation in BIGH3 gene were identified using Polymerase chain reaction (PCR) and sequencing. RESULTS: The number of patients was ranked as follows: 30 patients (40.0%) with ACD, 24 patients (32.0%) with keratoconus, 7 patients (9.3%) with CDLI, 5 patients (6.7%) with Fuchs' dystrophy, 3 patients (4.0%) with CDRB. In the genetic examination, we identified R124H mutation in ACD, R124C mutation in CDLI and R555Q mutation in CDRB. During this study, we also identified a polymorphism (F540F) in exon 12. CONCLUSIONS: ACD associated with R124H mutation is the most common form of inherited corneal disorder in Korea. And in Korean patients with CDRB, this study is the first report about mutation R555Q.
Diagnosis ; DNA ; Exons ; Humans ; Keratoconus ; Korea ; Pedigree ; Polymerase Chain Reaction

Orbscan-II anterior system was used for early diagnosis of keratoconus. 48 Eyes of 24 patients with suspicious keratoconus were examined by Orbscan-II anterior system from Dec. 1999 to Dec. 2000 and followed up. The values of Diff and anterior chamber depth (ACD) were recorded. Results indicated that values of Diff and ACD were increased in 4 eyes of 2 patients with keratoconus trend during follow-up. Taking advantage of Orbscan-II anterior system to observe the values of Diff and ACD can early diagnose the sub-clinical keratoconus. The values of Diff and ACD can sensitively report the progression of keratoconus.
Anterior Chamber/pathology ; Cornea/pathology ; Corneal Topography/*instrumentation ; Corneal Topography/methods ; Evaluation Studies ; Keratoconus/*diagnosis ; Keratoconus/ultrasonography

This study was performed to evaluate epidemiology and progression of keratoconus in Korean. 122 patients(223 eyes)who visited Kang-Nam St.Mary's Hospital and Bu-Pyung our lady of mercy hospital with keratoconus from 1989 to 1998 were reviewed retrospectively. At the time of diagnosis, prevalence in male(75 patients)was greater than that in female(47 patients)and the rate bilateral involvement was 84.4%(103 patients). The average age was 18.33+/-6.79 years and there is no difference between that of male and female. The greatest number of patients(63 patients, 51.6%)had been diagnosed from 15 to 24 years old. The mean astigmatism was 3.92+/-1.91 diopters. Of the 19 patients with unilateral keratoconus, 10 patients were followed up over three years(average follow period: 61months)and four reported that the disease had later been diagnosed in the contralateral eye. The greatest number of patients(107 eyes, 47.9%)had been examined from 0.02 to 0.1 in visual acuity without correction and 58 eyes(26.0%)achieved visual acuity with hard contact lens correction. Corneal findings included thinning(158 eyes), scarring(62 eyes), Fleischer ring(119 eyes), Vogt's striae(78 eyes). On corneal topography, a half of apex of cone(57 eyes of 107 eyes, 53.2%)was located in inferior temporal quadrant and highest rate of steepening(corneal power change away from the apex to the periphery along its semimeridian)was 2.70+/-1.48 diopters.
Astigmatism ; Corneal Topography ; Diagnosis ; Epidemiology ; Female ; Humans ; Keratoconus* ; Male ; Prevalence ; Retrospective Studies ; Visual Acuity ; Young Adult

We performed penetrating keratoplasty on the 40 eyes of 40 patients from Jan. 1991 through Dec. 1993, whose diagnosis was keratoconus. Among them, the opposite eyes of 5 patients had no keratoconus signs on the slit lamp biomicroscopic examination and keratometry reading. We performed computerassisted corneal topography on the 5 eyes and then they were classified as group I. We performed computer-assisted corneal topography on the 324 eyes of 324 patients. who visited our hospital to receive excimer laser photorefractive keratectomy(PRK). Among them, 7 eyes of 4 patients, which were suspected to be early keratoconus, were classified as group II. There were no signs of keratoconus by slit lamp examination and keratometry reading. Keratometry reading was 44.82D in the group I and 43.52D in the group II. Subtle mire distorsion of photokeratoscope was seen in the 1 eye of group I and 2 eyes of guoup II, but remaining 9 eyes were normal. We could not find keratoconus signs in the conventional examination such as above but on the corneal topography 12 eyes revealed cone-shaped corneal distorsion out of the corneal center. Two eyes in the group II were suspected to be early keratoconus in the corneal topographic examination, therefore we recommended them not to receive excimer laser PRK. But they received excimer laser PRK in the other hospital. They revisited our hospital due to progressively decreased visual acuity after excimer laser PRK. On the topography, 2nd and 12th months after PRK. corneal refractive power returned similarly to pre-PRK state. Therefore, computer-assisted corneal topography is a useful method in detecting corneal change in the early keratoconus stage. Performing PRK on the eye, suspected to be keratoconus, is unreasonable because corneal power is willing to return to pre-PRK state.
Corneal Topography ; Diagnosis* ; Humans ; Keratoconus* ; Keratoplasty, Penetrating ; Lasers, Excimer* ; Photorefractive Keratectomy* ; Visual Acuity

Adult ; Disease Progression ; Facial Hemiatrophy ; complications ; diagnosis ; physiopathology ; Female ; Humans ; Keratoconus ; etiology ; physiopathology ; therapy

In view of the problem that there is no standard diagnosis for early stage keratoconus disease,at the same time to assist the special examiner and ophthalmologist to make the early diagnosis effectively,the advantages and disadvantages of each testing instrument were analyzed.In order to construct an assistant system for early diagnosis of keratoconus,a deep learning technique was applied in corneal OCT examination.The system used improved VGG-16 to realize the recognition accuracy of about 68% keratoconus keratopathy,and the clinical results showed that the system can help doctors to give diagnosis confidence to a certain extent.At the same time,the physician's re-marking of OCT can help train the system for more accurate judgment.
Corneal Topography ; Deep Learning ; Early Diagnosis ; Humans ; Keratoconus ; diagnostic imaging ; Tomography, Optical Coherence

PURPOSE: To report the confocal morphological changes of keratoconus in comparison with that of normal cornea. METHODS: Confocal microscopy (ConfoScan 2.0, Fortune Technology, Italy) was used to obtain data from healthy volunteers and keratoconus. We evaluated corneal morphological images of the corneal epithelium, Bowman's layer, stromal layer (anterior, middle, and posterior keratocyte), Descemet's membrane, and endothelium. RESULTS: In keratoconus cornea, the wing cells of epithelium had somewhat irregular margin, and the subepithelial nerve bundle was slightly enlarged. Near Bowman's membrane, highly reflective changes and tear like structure were visible. While the anterior stromal keratocyte had nuclei with a highly reflective density and indefinite cell border, posterior keratocyte had a more distinct shape with less cellularity. Near descemet's membrane, vertical fold (Vogt's striae) was observed and keratocytes with long processes arranged nearly in parallel. Morphological change was not observed in the endothelium. CONCLUSIONS: Our confocal microscopic findings of keratoconus may help early diagnosis and assessment of prognosis in the management of keratoconus.
Bowman Membrane ; Cornea ; Descemet Membrane ; Early Diagnosis ; Endothelium ; Epithelium ; Epithelium, Corneal ; Healthy Volunteers ; Keratoconus* ; Microscopy, Confocal ; Prognosis

We conducted a retrospective study of 45 penetrating keratoplasties (39 patients) for keratoconus from March 1986 to February 1991 at St. Mary's Hospital, Catholic University Medical College. The follow-up period was at least over 1 year. The penetrating keratoplasties were performed most commonly in the interval between 1 and 5 years after the diagnosis of keratoconus (25 patients; 64.1%). The hard contact lenses were the most commonly used for visual correction before penetrating keratoplasty. Corneal scar was the most common indication for keratoplasty (35 eyes: 77.8%). The most common postoperative complication was loose suture (14 eyes; 31.1%). Overall, 43 out of the 45 corneal transplants (95.6%) remained clear and these eyes attained best-corrected visual acuity of 0.5 or better.
Cicatrix ; Contact Lenses ; Corneal Transplantation ; Diagnosis ; Follow-Up Studies ; Humans ; Keratoconus* ; Keratoplasty, Penetrating* ; Postoperative Complications ; Retrospective Studies ; Sutures ; Visual Acuity

The purpose of this study was to investigate the correlations between endothelial cell loss rate at one week, one month, three months, and six months after penetrating keratoplasty and clinical factors including recipient age, donor age, preoperative endothelial cell densities of the donors and preoperative diagnoses of the recipients. Among the 70 patients who underwent penetrating keratoplasty at Chonbuk University Hospital from December 1996 to January 1999, 30 eyes of 30 patients that showed reasonable endothelial resolution by non-contact specular microscopy during the follow up period of 6 months were chosen and evaluated.The cell density decreased continuously during the observation period. Endothelial cell loss rate averaged 11.5%at one week, 19.0% at one month, 25.0%at three months and 30.0%at six months after penetrating keratoplasty. Endothelial cell loss rate showed no significant correlation with donor age, recipient age, preoperative cell density at any examination period[r+/-0.4, p0.05]. Preoperative endothelial cell density showed significant correlation with postoperative endothelial cell density at each examination period[r0.7, p<0.05]. The rate of endothelial loss in the keratoconus group was significantly lower than those of bullous keratopathy or corneal leukoma groups at three months after penetrating keratoplasty[Wilcoxon test, p<0.05].
Cell Count ; Corneal Opacity ; Diagnosis ; Endothelial Cells* ; Follow-Up Studies ; Humans ; Jeollabuk-do ; Keratoconus ; Keratoplasty, Penetrating* ; Microscopy ; Tissue Donors