Phacoemulsification tip vacuum pressure: Comparison of 4 devices.

PURPOSE: To determine the vacuum pressure generated by 4 phacoemulsification devices measured at the phacoemulsification tip. SETTING: University ophthalmology department. METHODS: The effective vacuum pressures generated by the Sovereign (AMO), Millennium (Bausch & Lomb), Legacy AdvanTec (Alcon Laboratories), and Infiniti (Alcon Laboratories) phacoemulsification machines were measured with a device that isolated the phacoemulsification tip in a chamber connected to a pressure gauge. The 4 machines were tested at multiple vacuum limit settings, and the values were recorded after the foot pedal was fully depressed and the pressure had stabilized. The AdvanTec and Infiniti machines were tested with and without occlusion of the Aspiration Bypass System (ABS) side port (Alcon Laboratories). The Millennium machine was tested using venturi and peristaltic pumps. RESULTS: The machines generated pressures close to the expected at maximum vacuum settings between 100 mm Hg and 500 mm Hg with few intermachine variations. There was no significant difference between pressures generated using 19- or 20-gauge tips (Millennium and Sovereign). The addition of an ABS side port decreased vacuum by a mean of 12.1% (P < .0001). CONCLUSION: Although there were some variations in vacuum pressures among phacoemulsification machines, particularly when an aspiration bypass tip was used, these discrepancies are probably not clinically significant.

Continuous Curvilinear Capsulorhexis Performed With the VERUS Ophthalmic Caliper.

PURPOSE: To compare size, circularity, and centration outcomes of continuous curvilinear capsulorhexis (CCC) performed with or without assistance from the VERUS ophthalmic caliper (Mile High Ophthalmics, Denver, CO). METHODS: This was a multicenter retrospective consecutive case controlled series review. RESULTS: Data from 40 consecutive cases using the VERUS device for CCC were compared to 40 consecutive cases with standard manual CCC. VERUS-assisted CCC size, circularity, and centration were closer to target compared to that of manual only procedures (P < .05). The average time from initiation to completion of the capsulotomy was shorter with manual (40 ± 11 seconds) compared to VERUS-assisted (71 ± 13 seconds) cases (P < .0001). CONCLUSIONS: The VERUS ophthalmic caliper is effective at improving size, circularity, and centration of the CCC in a time-efficient manner when compared to manual procedures performed without VERUS guidance. [J Refract Surg. 2016;32(10):654-658.].

Emergency lateral canthotomy and cantholysis: a simple procedure to preserve vision from sight threatening orbital hemorrhage.

Retrobulbar hemorrhage is an uncommon, but potentially devastating complication associated with facial trauma. It can rapidly fill the orbit and cause an "orbital compartment syndrome" that subsequently cuts off perfusion to vital ocular structures, leading to permanent visual loss. Treatment must be initiated within a limited time in order to prevent these effects; however, specialty consultation is not always available in remote field environments. This article addresses the mechanism, diagnosis, and treatment ofretrobulbar hemorrhage via lateral canthotomy and cantholysis, and recommends that 18D medical sergeants be properly trained to evaluate and perform this sight-saving procedure in emergent settings where upper echelons of care are not immediately available.