PURPOSE: To determine the corneal topographic appearance in a pair of monozygotic twins and family members of the twins because one of the twins had keratoconus and the other appeared normal by clinical examination. METHODS: Clinical examination and videokeratography (Topographic Modeling System, Tomey) of the patient, his monozygotic twin brother, an older brother, and his parents were performed. The I-S values (difference in the average dioptric powers of symmetrical points between the inferior and superior cornea) were calculated. RESULTS: The patient, a 28-year-old man, had clinical keratoconus confirmed with videokeratography. Clinical examination of family members including a twin brother, an older brother and both parents revealed no corneal abnormalities. Videokeratography of the clinically normal twin brother showed inferior steepening with progression over time. The I-S value of the clinically normal brother was 1.36 (right eye) (greater than 2.00 SD of normal controls), which progressed to 1.69 (right eye), 1.32 (left eye) 5 months later and to 1.87 (right eye), 1.43 diopters (D) (left eye) 14 months later. Minimal asymmetric inferior steepening was noted in an older brother who had an I-S value of 0.81 (right eye), 1.27 (left eye). The mother appeared topographically normal. CONCLUSIONS: This study lends support to the existence of subclinical keratoconus detectable by videokeratography only.
PURPOSE: To determine the corneal topographic appearance in a pair of monozygotic twins and family members of the twins because one of the twins had keratoconus and the other appeared normal by clinical examination. METHODS: Clinical examination and videokeratography (Topographic Modeling System, Tomey) of the patient, his monozygotic twin brother, an older brother, and his parents were performed. The I-S values (difference in the average dioptric powers of symmetrical points between the inferior and superior cornea) were calculated. RESULTS: The patient, a 28-year-old man, had clinical keratoconus confirmed with videokeratography. Clinical examination of family members including a twin brother, an older brother and both parents revealed no corneal abnormalities. Videokeratography of the clinically normal twin brother showed inferior steepening with progression over time. The I-S value of the clinically normal brother was 1.36 (right eye) (greater than 2.00 SD of normal controls), which progressed to 1.69 (right eye), 1.32 (left eye) 5 months later and to 1.87 (right eye), 1.43 diopters (D) (left eye) 14 months later. Minimal asymmetric inferior steepening was noted in an older brother who had an I-S value of 0.81 (right eye), 1.27 (left eye). The mother appeared topographically normal. CONCLUSIONS: This study lends support to the existence of subclinical keratoconus detectable by videokeratography only.
Authors: Dimitrios Karamichos; Paulina Escandon; Brenda Vasini; Sarah E Nicholas; Lyly Van; Deanna H Dang; Rebecca L Cunningham; Kamran M Riaz Journal: Prog Retin Eye Res Date: 2021-11-02 Impact factor: 19.704
Authors: Vishal Shinde; Nara Sobreira; Elizabeth S Wohler; George Maiti; Nan Hu; Giuliana Silvestri; Sonia George; Jonathan Jackson; Aravinda Chakravarti; Colin E Willoughby; Shukti Chakravarti Journal: Hum Mol Genet Date: 2021-05-17 Impact factor: 6.150
Authors: Ewelina Synowiec; Katarzyna A Wójcik; Anna Czubatka; Piotr Polakowski; Justyna Izdebska; Jerzy Szaflik; Janusz Błasiak; Jacek P Szaflik Journal: Arch Med Sci Date: 2015-10-12 Impact factor: 3.318
Authors: Ewelina Synowiec; Katarzyna A Wojcik; Justyna Izdebska; Ewelina Binczyk; Janusz Blasiak; Jerzy Szaflik; Jacek P Szaflik Journal: Dis Markers Date: 2013-09-25 Impact factor: 3.434