The importance of central corneal thickness measurements and decision making in general ophthalmology clinics: a masked observational study.
BACKGROUND
To assess the impact of knowing central corneal thickness (CCT) on glaucoma management in a United Kingdom district general hospital.


METHODS
A masked observational non-interventional study included 304 eyes of 152 consecutive glaucoma cases attending general clinic. CCT was measured using a hand-held pachymeter. IOP, as measured by the Goldmann applanation tonometer (GAT), was adjusted for CCT using a normogram. Two identical study sheets were retrospectively constructed from each subject's case notes: one included the CCT and adjusted IOP information, the other excluded. Study sheets were randomly presented to a single masked observer to decide glaucoma management. The difference in management decision was noted.


RESULTS
The mean +/- standard deviation CCT was 561.5 +/- 35.7 microm, 538.9 +/- 41.4 microm, 538.3 +/- 40.3 microm for ocular hypertension (OHT), primary open angle glaucoma (POAG) and normal pressure glaucoma (NPG) subjects respectively. IOP adjustment was greater than +/-2 mmHg in 33.9%(103/304) of eyes. CCT and adjusted IOP information led to different treatment option in 37%(55/152). Of the most important changes 20.4%(31/152) cases would have been commenced on additional IOP-lowering medication, 2.0%(3/152) would have been counselled for trabeculectomy surgery and 3.3%(5/152) of the cohort would have been observed rather than treated.


CONCLUSIONS
CCT and adjusted IOP measurement can influence glaucoma management in a clinical context. It helps attribute risk and hence aids patient management decisions.
Patwardhan
Ashish A
AA
Department of Ophthalmology, Shrewsbury and Telford Hospitals NHS Trust, Shrewsbury, UK. apatwa@hotmail.com
Khan
Mohammad
M
Mollan
Susan P
SP
Haigh
Paul
P
D000368:Aged; D003315:Cornea / Q000000981:diagnostic imaging* / Q000473:pathology; D018450:Disease Progression; D005260:Female; D005902:Glaucoma, Open-Angle / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D008297:Male; D009798:Ocular Hypertension / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D011379:Prognosis; D012720:Severity of Illness Index; D016037:Single-Blind Method; D014463:Ultrasonography