Impact of fluidic parameters during phacoemulsification on the anterior vitreous face behavior: Experimental study

Abstract

Purpose:To evaluate the eff ect of different aspiration flow rates (AFR) and bottle heights (BH) on vitreous face (AVF) during phacoemulsifi cation.Methods:Experimental study in 20 porcine eyes. Transzonular viscodissection was performed between the posterior capsule(PC) and AVF to dissect out the Berger's space. Triamcinolone acetonide was injected into this space to aid visualization with ultrasound B-Scan(USG). Realtime USG was performed during phacoemulsifi cation. Eyes were divided randomly into–Group I: Low parameters(AFR = 20 cc/min, BH = 90 cm, vacuum = 400 mmHg), and Group II: High parameters (AFR = 40 cc/min, BH = 110 cm, vacuum=650 mm Hg).Results:15 eyes were analysed (8 in Group I; 7 in Group II). In all eyes, forward and backward movement of the PC was seen when going from foot position 0 to 1, or on occlusion break. Amplitude of these movements was much greater in Group II compared to Group I. There was no PC rupture in either group. In 2 of the 7 eyes in Group II, USG showed a sudden, spontaneous dispersion appearance of sono-opaque echoes in the vitreous cavity alongwith disappearance of the well-defi ned, crescentic stained space despite an intact PC. This suggests rupture of the AVF, leading to dispersion of the triamcinolone into the entire vitreous cavity. No AVF rupture was seen in Group I.Conclusion:We report a rarely described entity of AVF rupture with intact PC. The use of high AFR and BH may have clinically invisible detrimental consequences to the anterior vitreous face.

Anterior vitreous detachment and retrolental material during cataract surgery: incidence and risk factors, with pathological evidence

“…Vasavada et al showed that the incidence of AHM rupture during phacoemulsification was positively correlated with the aspiration flow rates and bottle heights. 14 Similarly, in porcine eyes, Kawasaki et al showed that AHM rupture is associated with intraocular pressure. 13 However, there were few reports of AHM rupture in human eyes in the literature.…”

Incidence and Risk Factors for Berger’s Space Development after Uneventful Cataract Surgery: Evidence from Swept-Source Optical Coherence Tomography

“…Crucially, BS may be enlarged by excessive irrigation fluid circulation that moves through weakened zonules and incomplete attachment of the Wieger ligament during phacoemulsification. Vasavada et al [33] reported that using high fluidic parameters during phacoemulsification caused partial AHD with an intact posterior lens capsule. We observed that eyes with BS had higher irrigation pressures (p < 0.001, Table 1).…”

“…The presence or increasing width of BS or AHD may lead to complications during or after cataract surgery. Vasavada et al [33] reported that the use of high bottle heights and aspiration flow rates may have detrimental consequences on the anterior vitreous face, which are clinically undetectable. This causes decompartmentalization and allows the diffusion of infectious microbes and inflammatory mediators through zonules into BS, consequently increasing the risk of vitritis, macular edema, or even endophthalmitis.…”

Does low infusion pressure microincision cataract surgery (LIPMICS) reduce frequency of post-occlusion breaks?

“…Vasavada et al also examined the anterior vitreous face during phacoemulsification using different AFR and target IOP settings on porcine eyes. They reported 2 cases of ruptured anterior vitreous face in the higher fluidic settings (AFR = 40 cc/ min, bottle height = 110 cm, vacuum = 650 mm Hg) [ 10 ]. Hejsek et al evaluated IOP fluctuations and calculated the mean ocular perfusion pressure during phacoemulsification on patients.…”