Posters

Postural changes in Ocular Perfusion Pressure correlates with RNFL thickness in Normal Tension Glaucoma

Poster Details

First Author: F.Lim SINGAPORE

Co Author(s):    N. Porporato   B. Mani   T. Aung   C. Ho           

Abstract Details

Purpose:

To investigate how IOP and OPP change with posture in untreated NTG patients compared to controls.

Setting:

Observational, non-interventional, single centre, hospital-based cohort study in Singapore national eye centre

Methods:

95 NTG patients and 20 controls. IOP was measured after lying supine for 0 minutes, 30 minutes and 60 minutes. Blood pressure and pulse rate were measured in both sitting and supine positions at 0 mins, 30 mins and 60 mins. OPP was calculated from IOP and mean arterial pressure (MAP). Main outcome measures are mean IOP, change in IOP, OPP, change in OPP between NTG patients and controls in sitting and supine positions at 0, 30 and 60 minutes and the correlation of these parameters with the retinal nerve fibre layer (RNFL) thickness.

Results:

There is a significant rise in mean IOP from lying to supine position in both groups, most pronounced in the first 30 minutes after lying supine (p<0.001), thereafter the IOP remains similar from 30 to 60 minutes. Amongst the NTG patients, the group that experienced a negative postural change in OPP (i.e. the OPP dropped after adopting the supine position) had significantly thinner RNFL compared with those with small (0-10%) and great (>10%) postural change.

Conclusions:

Besides IOP, mean arterial pressure (OPP) and related autonomic dysregulation resulting from postural change plays a role in glaucoma pathophysiology in NTG patients.

Financial Disclosure:

None