Phacoemulsification using an Active Fluidics System at Physiologic versus High IOP: Impact on Anterior and Posterior Segment Physiology.

PURPOSE: Evaluate the impact of high vs low intraoperative IOP during phacoemulsification on anterior and posterior physiology. SETTING: Private practice in Des Moines, Iowa. DESIGN: Prospective, randomized, paired-eye clinical trial of patients anticipating bilateral cataract surgery. METHODS: Twenty-seven subjects randomized at the time of their first cataract surgery to either low intraocular pressure (IOP) or high IOP group. The subsequent cataract surgery was done under the alternate condition. During phacoemulsification and cortex removal, IOP was maintained either at low (≤28 mmHg) or at high (≥55-60 mmHg) levels. The primary outcome was fluid usage, with secondary outcomes of central corneal thickness, FAZ (foveal avascular zone) area, foveal and macular thickness, endothelial cell density and post-operative inflammation. RESULTS: Surgery with low IOP settings used less fluid (40.0cc v 55.6 cc, p<0.0001). Corneal thickness changes were smaller in low IOP eyes at 1 day and 1 week (3.0% v 8.1%, p=0.01; 3.1% v 4.4%, p=0.01) but were similar by 1 and 3 months. Endothelial cell density (ECD) dropped less in low IOP eyes at 1 and 3 months (-1.7%v-12.3%, p=0.001, 2.1% vs -8.9%, p=0.0003.) IOP remained a significant predictor of ECD change when relationship was controlled for fluid use and phaco energy. Retinal parameters did not vary among all eyes or when compared by IOP setting. Visual acuity was similar at all time points. CONCLUSIONS: Low IOP settings resulted in less inflammation and less corneal trauma, as evidenced by a smaller drop in endothelial cell density and less postop corneal edema, when compared to high IOP settings. Retinal parameters did not change significantly. The different outcomes did not result in a difference in visual acuity.

Suture Fixation to Reduce Graft Detachment in Descemet Stripping Endothelial Keratoplasty.

PURPOSE: The aim of this study was to report the outcomes of graft fixation using interrupted, full-thickness sutures on graft detachment after Descemet stripping endothelial keratoplasty (DSEK). METHODS: All DSEK procedures performed at Mayo Clinic, Rochester, MN, from 2015 through 2022 were retrospectively reviewed. Risk factors for graft detachment were defined as previous incisional glaucoma surgery, previous penetrating keratoplasty, or absence of the normal lens-capsule barrier. Cases were categorized into sutured, high-risk grafts; unsutured, high-risk grafts; and unsutured, low-risk grafts. The primary outcome was graft detachment, and secondary outcomes were early graft failure and graft clarity at 12 months after surgery. RESULTS: Demographics between the high-risk groups were similar for sex and age at the time of surgery. Graft detachment occurred in 4 of 97 sutured, high-risk eyes (4.1%) and 24 of 119 unsutured high-risk eyes (20.2%) ( P = 0.002). In comparison, graft detachment occurred in 18 of 181 unsutured low-risk eyes (9.9%). The incidence of early graft failure was 2.1%, 5.0%, and 3.3% and late graft failure by 12 months was 9.8%, 12.8%, and 4.2%, respectively. CONCLUSIONS: In eyes with high-risk factors for graft detachment, suture fixation of the graft in DSEK decreased graft detachment to a rate at least as low as that in low-risk eyes.

Impact of eye bank lamellar tissue cutting for endothelial keratoplasty on bacterial and fungal corneoscleral donor rim cultures after corneal transplantation.

PURPOSE: To determine if the lamellar cut of donor tissue for endothelial keratoplasty (EK) by an eye bank facility is associated with a change in the prevalence of positive bacterial or fungal donor rim cultures after corneal transplantation. METHODS: A retrospective review was conducted of bacterial and fungal cultures of donor rims used for corneal transplantation at a tertiary eye care center from January 1, 2003, to December 31, 2008, with tissue provided by a single eye bank. The cases were divided into 2 groups. Group 1 ("no-cut") included keratoplasty procedures in which a lamellar cut was not performed. Group 2 ("precut") included EK procedures in which a 4-hour period of prewarming of tissue followed by a lamellar cut was performed in the eye bank before tissue delivery to the operating surgeon. RESULTS: There were 351 donor rim cultures in group 1 and 278 in group 2. Bacterial cultures were positive in 30 donor rims (8.5%) in group 1 and 13 (4.7%) in group 2 (P = 0.058). Positive bacterial cultures were not associated with any postoperative infections. Fungal cultures were positive in 8 donor rims (2.3%) in group 1 and 7 (2.5%) in group 2 (P = 1.0). Positive fungal cultures were associated with 2 cases (13.3%) of postoperative fungal infections. CONCLUSIONS: Corneal donor tissue can be precut for EK by trained eye bank personnel without an increased risk of bacterial or fungal contamination.

Glaucoma therapy escalation in eyes with pseudophakic corneal edema after penetrating keratoplasty and Descemet's stripping automated endothelial keratoplasty.

The purpose of this study was to determine and compare the prevalence of glaucoma therapy escalation (GTE) after penetrating keratoplasty (PKP) and Descemet's stripping automated endothelial keratoplasty (DSAEK) in eyes with a surgical indication of pseudophakic corneal edema. A retrospective review was conducted of the medical records of all patients who underwent PKP or DSAEK to treat pseudophakic corneal edema at a tertiary eye care center from January 1 2003 to December 31, 2006. Eyes that were treated with PKP from January 1, 2003 to December 31, 2004 and with DSAEK from January 1, 2005 to December 31, 2006 were included in the statistical analysis. Inclusion criteria included satisfactory preoperative control of intraocular pressure (IOP) and follow-up of at least 12 months. The main outcome measure was GTE, which was defined as a sustained requirement for escalation of topical medical therapy or the need to provide surgical intervention to maintain a satisfactory postoperative IOP. Among 54 eyes that met the inclusion criteria, GTE occurred in 7 (35.0%) of 20 eyes after PKP and in 14 (41.2%) of 34 eyes after DSAEK (P = 0.78) during a mean follow-up period of 27.6 and 28.6 months, respectively. Surgical escalation occurred in 2 (10.0%) eyes after PKP and 2 (5.9%) eyes after DSAEK (P = 0.62), and was associated with late-onset endothelial graft failure in all four eyes. Glaucoma therapy escalation is relatively common and occurs with comparable frequency in eyes with pseudophakic corneal edema after PKP and DSAEK.

Initial resident refractive surgical experience: outcomes of PRK and LASIK for myopia.

PURPOSE: To evaluate and compare the outcome of initial resident surgical experience with photorefractive keratectomy (PRK) and LASIK. METHODS: Retrospective review of all cases performed with the VISX Star S4 platform (Abbott Medical Optics) between July 1, 2003 and June 30, 2007. Inclusion criteria were spherical equivalent of -0.50 to -10.00 diopters (D), refractive astigmatic error of ≤3.00 D, intention to provide full distance correction, and minimum 3-month postoperative follow-up after initial ablation or retreatment (if performed). RESULTS: A total of 153 cases performed by 20 different residents met the inclusion criteria; 38 eyes underwent PRK and 115 eyes had LASIK. After initial treatment, mean Snellen uncorrected distance visual acuity (UDVA) after PRK was 20/17.3 and after LASIK was 20/19.5. Photorefractive keratectomy was associated with a significantly better approximation between preoperative corrected distance visual acuity (CDVA) and postoperative UDVA (ΔlogMAR 0.009 vs 0.091; P=.004) and a greater percentage of eyes that achieved UDVA of 20/20 or better (94.7% vs 78.3%; P=.02) or 20/30 or better (100% vs 87.8%; P=.02). There was a higher prevalence of retreatment in eyes that underwent LASIK (7.0% vs 0%; P=.20). One (0.9%) eye lost 2 lines of CDVA after LASIK. CONCLUSIONS: Supervised refractive surgery residents can achieve excellent visual outcomes in patients operated during their initial refractive experience. Photorefractive keratectomy was associated with better visual outcome than LASIK.

Surgical management of a posterior dislocated intraocular lens after descemet stripping automated endothelial keratoplasty.

PURPOSE: To describe the occurrence and management of a posterior chamber intraocular lens (IOL) dislocation into the vitreous cavity after Descemet stripping automated endothelial keratoplasty (DSAEK). METHODS: We describe the clinical course of a pseudophakic patient with Fuchs endothelial dystrophy and previous Neodymium: Yttrium-Aluminum-Garnet (Nd:YAG) laser capsulotomy who underwent DSAEK. On postoperative day 10, the patient was examined and a detachment of the DSAEK graft was noted. After disc reattachment with use of an air bubble, the patient's vision did not clear because of persistent edema, but he appreciated a new large floater. A diagnosis of iatrogenic graft failure was made, and ultrasound examination confirmed dislocation of a plate-haptic silicone IOL into the vitreous cavity. The patient was treated with pars plana vitrectomy and concurrent penetrating keratoplasty. RESULTS: One year after penetrating keratoplasty, the patient had a visual acuity of 20/60 with mild neurotrophic keratopathy and irregular astigmatism. CONCLUSION: The use of intraocular air at the time of graft repositioning can induce posterior dislocation of an IOL in the setting of a YAG capsulotomy opening.

Parachute-like harness to position patients with severe kyphosis during cataract surgery.

We describe a technique to position patients with severe kyphosis so the head is horizontal. The legs are lifted into the Trendelenburg position, and the patient is supported with straps similar to those of a parachute. Although the patient's legs are high above the head and jugular distension has been observed, we have not noticed posterior pressure in the 2 cases we describe. This technique is similar to that described by others but has the additional security of the parachute-like straps.

Genotoxin-induced Rad9-Hus1-Rad1 (9-1-1) chromatin association is an early checkpoint signaling event.

Rad17, Rad1, Hus1, and Rad9 are key participants in checkpoint signaling pathways that block cell cycle progression in response to genotoxins. Biochemical and molecular modeling data predict that Rad9, Hus1, and Rad1 form a heterotrimeric complex, dubbed 9-1-1, which is loaded onto chromatin by a complex of Rad17 and the four small replication factor C (RFC) subunits (Rad17-RFC) in response to DNA damage. It is unclear what checkpoint proteins or checkpoint signaling events regulate the association of the 9-1-1 complex with DNA. Here we show that genotoxin-induced chromatin binding of 9-1-1 does not require the Rad9-inducible phosphorylation site (Ser-272). Although we found that Rad9 undergoes an additional phosphatidylinositol 3-kinase-related kinase (PIKK)-dependent posttranslational modification, we also show that genotoxin-triggered 9-1-1 chromatin binding does not depend on the catalytic activity of the PIKKs ataxia telangiectasia-mutated (ATM), ataxia telangiectasia and Rad3-related (ATR), or DNA-PK. Additionally, 9-1-1 chromatin binding does not require DNA replication, suggesting that the complex can be loaded onto DNA in response to DNA structures other than stalled DNA replication forks. Collectively, these studies demonstrate that 9-1-1 chromatin binding is a proximal event in the checkpoint signaling cascade.