Abstract
Purpose: :
To investigate the correlation of blood pressure with normal–tension glaucoma (NTG) with asymmetric visual field change and asymmetric intraocular pressure (IOP).
Methods: :
The subjects were 50 eyes in 25 patients with untreated NTG(15 males and 10 females) whose mean age was 50.0 ±12.6 years. The exclusion criteria were that patients had the absolute value of difference in mean deviation (MD) between right and left eye<1dB, the absolute value of difference in 24–hour mean IOP (mean of untreated 24–hour IOP measured at all time points) <0.5 mmHg between right and left eye , and the absolute value of difference in refractive error between right and left eye>2D . Patients were hospitalized, and IOP was measured at 10 AM, 1 PM, 4 PM, 7 PM, 10 PM, 1 AM, 3 AM, and 7 AM with a Goldmann applanation tonometer in the sitting position. Blood pressure was measured at 9∼11 AM. The subjects were divided into a group with higher 24–hour mean IOP in the eye that had a better mean MD (concordant group) and a group with higher 24–hour mean IOP in the eye that had worse MD (discordant group).
Results: :
There were 15 patients in the concordant group and 10 in the discordant group.The systolic, diastolic and mean blood pressure were significantly higher in the concordant group than the discordant group(P=0.0426,P=0.0350 and P=0.0198,respectively). There were 5 patients with history of systemic hypertension in the concordant group but none in the discordant group (P=0.0455) . The ocular perfusion pressure(OPP) was significantly lower in the discordant group than in the concordant group [OPP of the eye with worse MD (%):concordant group :52.3±10.7, discordant group:42.7±4.8, P=0.0171,OPP of the eye with better MD(%): concordant group :52.1±11.0, discordant group :42.3±4.7,P=0.0136].
Conclusions: :
The progression of visual field disorders in some patients with NTG may be affected not only by the IOP but also by their systemic blood pressure.
Keywords: intraocular pressure • visual fields • circadian rhythms