Intraocular Pressure Course During the Femtosecond Laser-Assisted Cataract Surgery in Porcine Cadaver Eyes

Abstract

PURPOSE. Femtosecond laser-assisted cataract surgery (FLACS) is an increasingly common procedure. Most laser systems require corneal applanation and thereby increase intraocular pressure (IOP). The purpose of the present study was to evaluate the IOP changes that occur during the FLACS procedure performed using the Catalys femtosecond laser system. METHODS. IOP was measured by direct cannulation of the vitreous body of porcine cadaver eyes (N ¼ 20). By inserting a second cannula connected to a water column, all the eyes were set to a baseline IOP of 20 mm Hg. The eyes were lifted by custom-made stands to achieve the appropriate height and position under the Catalys system. The standard FLACS procedure was performed using varying fragmentation times to assess the influence of tissue fragmentation times on IOP peaks. RESULTS.We identified significant IOP elevations from baseline IOP levels during all steps of the FLACS procedure (baseline: 20.28 6 1.32 mm Hg; vacuum: 34.48 6 4.21 mm Hg; capture: 47.90 6 13.02 mm Hg; lock: 48.41 6 9.04 mm Hg; analysis: 47.15 6 5.97 mm Hg; capsulotomy: 45.74 6 6.52 mm Hg; fragmentation: 48.41 6 6.80 mm Hg; end: 17.81 6 1.61 mm Hg; all P < 0.001). Furthermore, the tissue fragmentation time had a significant effect on the peak IOP values detected (R ¼ 0.62, P ¼ 0.04, n ¼ 9).CONCLUSIONS. The present study reveals significant IOP increases during FLACS procedures carried out using the Catalys system.

Preoperative intraocular pressure as a strong predictive factor for intraocular pressure rise during vacuum application in femtosecond laser‐assisted cataract surgery

“…; Sperl et al. ). However, comparison of the results of those two studies indicates a correlation between the baseline IOP and the IOP during vacuum application.…”

“…; Sperl et al. ). In contrast, studies investigating the Ziemer LDV Z8 platform showed about 10 mmHg higher IOP values with comparable preoperative baseline IOP (Williams et al.…”

“…; Sperl et al. ). Despite the clear trend that vacuum and much more the preoperative IOP were predictive factors for IOP rise during femtosecond laser‐assisted cataract surgery, an experimental ex‐vivo setup as used in our study, should always be considered with regards to its limitations when interpreting the results.…”

Microvascular changes in macula and optic nerve head after femtosecond laser-assisted LASIK: an optical coherence tomography angiography study

“…Besides, the rapid development of femtosecond (10 − 15 s) lasers over the past two decades has opened up new applications in ophthalmic surgery [12] such as FLEx (FS laser lenticular extraction), SMILE (small-incision lenticular extraction), FLACS (FS laserassisted cataract surgery), etc. Many studies have revealed significant IOP increases during FS laser-assisted procedures [15][16][17]. In spite of changes in intraocular pressure, a phenomenon called retinal autoregulation [18][19][20][21] is able to maintain blood flow and oxygen supply to the fundus at a constant level.…”

Anatomic Studies of the Miniature Swine Cornea

“…Swine are increasingly being used in ophthalmology and vision science research to model various ocular diseases (Stricker-Krongrad et al, 2016), develop surgical techniques (Tasaka et al, 2013; Ibarz et al, 2016; McQuaid et al, 2016; Nanavaty and Kubrak-Kisza, 2017; Speri et al, 2017; Tandogan et al, 2016), novel therapies and intervention strategies (Umazume et al ., 2013; Scott et al, 2015; Wang et al, 2016; Lin et al, 2017; Drozhz- hyna et al, 2017; Cong et al, 2018) to prevent vision loss in humans due to similar ocular anatomy and physiology (Beauchemin, 1974; De Schaepdrijver et al, 1992; Gerke et al, 1995; Bartholomew et al, 1997; Ninomiya and Inomata, 2006; Acosta et al ., 2009; Sanchez et al ., 2011). Although studies (Bartholomew et al, 1997; Faber et al, 2008; Jay et al, 2008) have examined anatomical features of the domestic swine cornea, none have compiled a characterization of miniature corneal morphology at both the light and electron microscopic level.…”