97th DOG Annual Meeting 1999

P365

AUTOREGULATION OF RETINAL PERFUSION IN HEALTHIES AND PATIENTS WITH ATHEROSCLEROSIS OR LOW TENSION GLAUCOMA

D. Werner, J. Harazny*, J. Welzenbach*, J.-U. Voigt, G. Michelson*, W. G. Daniel

Pneumatic external counterpulsation (PECP, Vasomedical Inc., Westbury, USA) is a new therapy to increase coronary and cerebral perfusion. ECG-triggered diastolic compression of the lower extremities causes second retrograde pulse wave. First studies demonstrated a visual improvement in pts with occlusion of central retinal artery or ischemic optic neuropathy after PECP. In this study, effect of PECP on blood flow in the ophthalmic artery (AO) was investigated.

Method: Flow velocity (v) in AO was measured in 12 volunteers and 12 pts with severe atherosclerosis by sonography before and during PECP. The same investigation was carried out in 8 pts with low-tension-glaucoma (LTG).

Results: * p<0,01

 

v [cm/s]

  

Mean

Systolic

Diastolic

Volunteers

At rest

28.1

36.1

21.6

PECP

26.5 (-5.7%)

28.9 (-19.9%)*

23.7 (+9.7%)

Atheroscl.

At rest

26.3

34.2

19.7
 

PECP

29.3 (+11.4%)*

32.6 (-4.7%)

23.9(+21.3%)*

 

 5 LTG-pts had normal, 3 (38 %) had disturbed autoregulation during PECP.

Discussion: In healthy volunteers, diastolic augmentation leads to a reduced systolic flow velocity and no significant change in mean flow velocity. In atherosclerotic arteries, mean flow velocity increased as a result of disturbed autoregulation. Pattern of flow during PECP can be used to assess autoregulation and explains the clinical benefits of PECP in ocular diseases caused by disturbed perfusion. Disturbed regulation in some LTG pts indicates a vascular component of this disease.

II. Med. Clinic and Eye Clinic*, FAU, Erlangen

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