This article is more than 5 years old. Information may no longer be current.
Venturi vacuum yields efficiency without increasing risk for capsular breakage
Click Here to Manage Email Alerts
WAIKOLOA, Hawaii – Venturi vacuum is not more likely than peristaltic vacuum to break the capsular bag during phacoemulsification, according to a study presented here.
“Venturi vacuum does not increase the risk of capsular breakage with ultrasound,” Randall J. Olson, MD, said at Hawaiian Eye. “[Capsular breakage] comes from tip contact and not occlusion of the overall tip. You need ultrasound. And transversal [ultrasound] is significantly more likely to break the capsule.”
Randall J. Olson
Olson and colleagues set out to determine whether venturi vacuum, while more efficient than peristaltic vacuum, increases the risk for capsular breakage.
“We had to look and see if there is a price to pay for that increased efficiency. Physics is like a double-edged sword. Typically, if you get one thing on one side, you lose something on the other. It’s hard to get something for nothing. So, we thought that there was a potential risk factor for that increased efficiency,” Olson said.
Venturi and peristaltic vacuum were set at 550 mm Hg and bottle height was set at 50 cm, resulting in a flow rate of 40 mL/min for peristaltic and more than 100 mL/min for venturi. Phaco power was set at 50%. The venturi and peristaltic systems were tested with the phaco tip bevel up and down.
Results showed that with the bevel up, the capsule broke in 66.3% of cases with peristaltic vacuum and 60.3% of cases with venturi vacuum. With the bevel down, there was a 0% rate of capsular breakage, Olson said.
With transversal ultrasound, the capsule broke in 71% of cases with peristaltic vacuum and in 68.5% of cases with venturi vacuum. With micropulse, the capsule broke in 61.5% of cases with peristaltic vacuum and 52% with venturi, he said.
“I think that motion being side to side is a little bit more dangerous,” Olson said. – by Matt Hasson and Patricia Nale, ELS
Reference:
Olson RJ. Is venturi vacuum more likely to break the capsule? Presented at: Hawaiian Eye; Jan. 16-22, 2016; Waikoloa, Hawaii.
Disclosure: Olson reports no relevant financial disclosures.
Collapse
Click Here to Manage Email Alerts