OBJECTIVE To determine the central retinal vessel collapse pressure in patients with dilated episcleral veins. METHODS This clinical noninterventional comparative study included a study group of 10 eyes (6 patients) with dilated episcleral veins, and a control group consisting of 50 eyes of 40 patients with cataract or refractive problems. With topical anesthesia, a Goldmann contact lens fitted with a pressure sensor in its holding ring was placed onto the cornea. Pressure was asserted onto the globe by pressing the contact lens, and the pressure value at the time when the central retinal artery and vein started pulsating was noted as central retinal artery and vein collapse pressure. RESULTS Central retinal vein collapse pressure was significantly higher (P<0.001) in the study group with dilated episcleral veins than in the control group (37.9 +/- 33.8 vs 5.1 +/- 8.4 relative units [RU]). In the central retinal artery, there was not significant difference in diastolic collapse pressure measured between the study and control groups (78.2 +/- 22.8 vs 74.2 +/- 18.8 RU, respectively; P = 0.74). CONCLUSIONS As measured by a new ophthalmodynamometer with biomicroscopic visualization of the central retinal vessels during the examination, the central retinal vein collapse pressure measurements were significantly higher in eyes with dilated episcleral veins than in control eyes. Ophthalmodynamometric estimation of the central retinal vein collapse pressure may be helpful in the assessment of patients with dilated episcleral veins.