Kendall E. Donaldson

Femtosecond laser-assisted cataract surgery.

Femtosecond laser-assisted cataract surgery provides surgeons an exciting new option to potentially improve patient outcomes and safety. Over the past 2 years, 4 unique laser platforms have been introduced into the marketplace. The introduction of this new technology has been accompanied by a host of new clinical, logistical, and financial challenges for surgeons. This article describes the evolution of femtosecond laser technology for use in cataract surgery. It reviews the available laser platforms and discusses the necessary modifications in cataract surgery technique and the logistics of incorporating a femtosecond laser into ones practice.

Energy expenditure and symptom severity in men with heart failure

Our results demonstrate a graded increase in resting metabolic rate based on symptom severity as reflected in the New York Heart Association classification. This finding supports the hypothesis that clinical severity of illness corresponds to the magnitude of the increase in resting energy demands.

Anterior chamber and sutured posterior chamber intraocular lenses in eyes with poor capsular support.

Purpose: To compare the clinical outcomes and complications of patients who had surgical placement of anterior chamber (AC IOLs) and sutured posterior chamber intraocular lenses (PC IOLs) after cataract surgery resulting in poor capsular support. Setting: Department of Ophthalmology, Bascom Palmer Eye Institute, Miami, Florida. Methods: A retrospective interventional comparative case series of 181 eyes of 181 patients that had implantation of an intraocular lens with inadequate capsular support was conducted. A chart review of all patients that had implantation of AC IOLs or sutured PC IOLs at a tertiary care eye hospital between 1995 and 2001 was conducted. Results: Outcome measures included final best‐corrected visual acuity, spherical equivalent, and postoperative complications (pseudophakic bullous keratopathy, elevated intraocular pressure [IOP] inflammation, retinal detachment, suture erosion, cystoid macular edema). Of 702 charts reviewed, 181were found to fit inclusion and exclusion criteria. The postoperative complication risk ratio was 0.80 (95% confidence interval [CI]: 0.52–1.23) for AC IOLs compared with PC IOLs. The most common complication experienced by patients having implantation of either lens type was elevated IOP (AC IOL: 38%; PC IOL: 42%). The incidence of other complications was similar between the groups. Best‐corrected visual acuity was similar; however, final spherical equivalent trended toward more myopic values in the PC IOL group (−0.82 ± 1.67 for AC IOL versus −1.32 ± 2.12 for PC IOL). Conclusions: The findings suggest that no significant differences in outcome exist when comparing AC IOLs to sutured PC IOLs in complicated cataract extraction with poor capsular support. Recent advances in AC IOL design have yielded lenses that provide a safe, effective alternative to sutured PC IOLs.

Femtosecond Lasers for LASIK Flap Creation: A Report by the American Academy of Ophthalmology

OBJECTIVE To review the published literature to assess the safety, efficacy, and predictability of femtosecond lasers for the creation of corneal flaps for LASIK; to assess the reported outcomes of LASIK when femtosecond lasers are used to create corneal flaps; and to compare the differences in outcomes between femtosecond lasers and mechanical microkeratomes. METHODS Literature searches of the PubMed and Cochrane Library databases were last conducted on October 12, 2011, without language or date limitations. The searches retrieved a total of 636 references. Of these, panel members selected 58 articles that they considered to be of high or medium clinical relevance, and the panel methodologist rated each article according to the strength of evidence. Four studies were rated as level I evidence, 14 studies were rated as level II evidence, and the remaining studies were rated as level III evidence. RESULTS The majority of published studies evaluated a single laser platform. Flap reproducibility varied by device and the generation of the device. Standard deviations in flap thicknesses ranged from 4 to 18.4 μm. Visual acuities and complications reported with LASIK flaps created using femtosecond lasers are within Food and Drug Administration safety and efficacy limits. Of all complications, diffuse lamellar keratitis is the most common after surgery but is generally mild and self-limited. Corneal sensation was reported to normalize by 1 year after surgery. Unique complications of femtosecond lasers included transient light-sensitivity syndrome, rainbow glare, opaque bubble layer, epithelial breakthrough of gas bubbles, and gas bubbles within the anterior chamber. CONCLUSIONS Available evidence (levels I and II) indicates that femtosecond lasers are efficacious devices for creating LASIK flaps, with accompanying good visual results. Overall, femtosecond lasers were found to be as good as or better than mechanical microkeratomes for creating LASIK flaps. There are unique complications that can occur with femtosecond lasers, and long-term follow-up is needed to evaluate the technology fully.

No evidence for a higher resting metabolic rate in noninstitutionalized Alzheimer's disease patients.

OBJECTIVE: It has previously been suggested that Alzheimers disease patients have higher resting energy requirements than healthy individuals, which may contribute to their unexplained weight loss. We examined whether resting metabolic rate, the largest component of daily energy expenditure, is elevated in Alzheimers patients compared with healthy older controls.

Evaluation and treatment of children with ocular rosacea.

Purpose: To describe the clinical presentation and treatment of ocular rosacea in children, an often unrecognized entity. Methods: Retrospective chart review of 20 patients (age, 22 months to 17 years) who presented during childhood with corneal pathology, lid margin disease, and skin changes consistent with ocular rosacea. All patients were evaluated by the Cornea/External Disease Division of a tertiary-care facility, Bascom Palmer Eye Institute, Miami, FL, between 1990 and 2003. Results: Sixty percent of patients improved after treatment with systemic erythromycin or doxycycline and topical low-dose steroid preparations. Ten percent of patients experienced no change in symptoms with treatment, and 30% of patients had incomplete follow-up to determine success of treatment. The patients maintained remission for up to 4 years after a slow taper of systemic treatment. The mean length of follow-up was 19.6 months (range, 0-9 years). Conclusions: Early recognition and treatment of ocular rosacea in children may improve patient outcome by limiting progression of corneal pathology, including scarring and vascularization.

Operating times of experienced cataract surgeons beginning femtosecond laser-assisted cataract surgery

Purpose To compare the time a patient spent in the operating room during femtosecond laser–assisted with that during traditional cataract surgery. Setting Academic tertiary referral center. Design Retrospective review. Methods Data from 3 attending surgeons who operated in the room that housed the femtosecond laser were collected from the first 6 months of the femtosecond laser’s use. The time in the operating room was measured from when the patients entered the room to the time they left. Traditional‐approach cases done in the room were compared with cases performed using the femtosecond laser (Catalys Precision Laser System). Results During the first 6 months, 420 cataract cases were performed in the operating room housing the femtosecond laser; the femtosecond laser was used in 162 cases (38.6%). Femtosecond laser–assisted surgeries were 11.1 to 12.1 minutes longer than traditional surgeries (P<.0001). When only routine cases were included in the comparison, the femtosecond laser–assisted approach remained 11.6 to 13.4 minutes longer (P<.0001). Conclusion The additional steps required to perform femtosecond laser–assisted cataract surgery resulted in a statistically significant longer time per case than the time required with a traditional approach. Financial Disclosures Dr. Culbertson is a consultant to Abbott Medical Optics, Inc., and Optimedica Corp. Dr. Yoo is a consultant to Alcon Laboratories, Inc., and Abbott Medical Optics, Inc. No other author has a financial or proprietary interest in any material or method mentioned.

Femtosecond Lasers for LASIK Flap Creation

OBJECTIVE To review the published literature to assess the safety, efficacy, and predictability of femtosecond lasers for the creation of corneal flaps for LASIK; to assess the reported outcomes of LASIK when femtosecond lasers are used to create corneal flaps; and to compare the differences in outcomes between femtosecond lasers and mechanical microkeratomes. METHODS Literature searches of the PubMed and Cochrane Library databases were last conducted on October 12, 2011, without language or date limitations. The searches retrieved a total of 636 references. Of these, panel members selected 58 articles that they considered to be of high or medium clinical relevance, and the panel methodologist rated each article according to the strength of evidence. Four studies were rated as level I evidence, 14 studies were rated as level II evidence, and the remaining studies were rated as level III evidence. RESULTS The majority of published studies evaluated a single laser platform. Flap reproducibility varied by device and the generation of the device. Standard deviations in flap thicknesses ranged from 4 to 18.4 μm. Visual acuities and complications reported with LASIK flaps created using femtosecond lasers are within Food and Drug Administration safety and efficacy limits. Of all complications, diffuse lamellar keratitis is the most common after surgery but is generally mild and self-limited. Corneal sensation was reported to normalize by 1 year after surgery. Unique complications of femtosecond lasers included transient light-sensitivity syndrome, rainbow glare, opaque bubble layer, epithelial breakthrough of gas bubbles, and gas bubbles within the anterior chamber. CONCLUSIONS Available evidence (levels I and II) indicates that femtosecond lasers are efficacious devices for creating LASIK flaps, with accompanying good visual results. Overall, femtosecond lasers were found to be as good as or better than mechanical microkeratomes for creating LASIK flaps. There are unique complications that can occur with femtosecond lasers, and long-term follow-up is needed to evaluate the technology fully.

Mitomycin-C in Corneal Surface Excimer Laser Ablation Techniques: A Report by the American Academy of Ophthalmology

OBJECTIVE To review the published literature assessing the efficacy and safety of mitomycin-C (MMC) as an adjunctive treatment in corneal surface excimer laser ablation procedures. METHODS Literature searches of the PubMed and Cochrane Library databases were last conducted on August 19, 2014, without language or date limitations. The searches retrieved a total of 239 references. Of these, members of the Ophthalmic Technology Assessment Committee Refractive Management/Intervention Panel selected 26 articles that were considered to be of high or medium clinical relevance, and the panel methodologist rated each article according to the strength of evidence. Ten studies were rated as level I evidence, 5 studies were rated as level II evidence, and the remaining 11 studies were rated as level III evidence. RESULTS The majority of the articles surveyed in this report support the role of MMC as an adjunctive treatment in surface ablation procedures. When MMC is applied in the appropriate concentration and confined to the central cornea, the incidence of post-surface ablation haze is decreased. Although a minority of studies that evaluated endothelial cell density (ECD) reported an MMC-related decrease in ECD, no clinical adverse outcomes were reported. CONCLUSIONS Over the past 15 years, the use of MMC during surgery in surface ablation has become widespread. There is good evidence of the effectiveness of MMC when used intraoperatively as prophylaxis against haze in higher myopic ablations. Although there are reports of decreased endothelial counts after the administration of MMC during surgery, the clinical significance of this finding remains uncertain, because no adverse outcomes were reported with as much as 5 years of follow-up. Optimal dosage, effectiveness as prophylaxis in lower myopic and hyperopic ablations, and long-term safety, particularly in eyes with reduced corneal endothelial cell counts from prior intraocular surgery, have yet to be established.

Comparison of surgically induced astigmatism between femtosecond laser and manual clear corneal incisions for cataract surgery

Purpose To assess the surgically induced corneal astigmatism (SIA) introduced by femtosecond laser–assisted clear corneal incisions (CCIs) for cataract extraction and to compare it with the SIA of manually created CCIs. Setting Bascom Palmer Eye Institute, Miller School of Medicine, Miami, Florida, USA. Design Prospective nonrandomized comparative case series. Methods Eyes received femtosecond laser–assisted CCIs (Group 1) or manual CCIs (Group 2). The surgical plan included 1 primary and 1 secondary port; the sites of the incisions were the same in both groups and were diametrically opposed between the right eye and left eye. The SIA was assessed using the preoperative and 1‐month postoperative keratometric values obtained from corneal topography examinations. Results This study included 72 eyes of 68 patients with a mean age of 69.0 years ± 9.87 (SD) (range 36 to 90 years). Thirty‐six eyes received femtosecond laser–assisted CCIs (Group 1) and 36 received manual CCIs (Group 2). The mean preoperative topographic corneal astigmatism was −1.19 ± 0.68 diopters (D) (range 0 to 2.50 D) and −0.92 ± 0.63 D (range 0.10 to 2.45 D) for Group 1 and Group 2, respectively, whereas, 1 month after cataract surgery, it was −1.16 ± 0.63 D (range 0.20 to 2.57 D) and −0.95 ± 0.64 D (range 0.21 to 2.37 D), respectively. Multivariate vector analysis revealed no statistically significant difference between the 2 groups for preoperative astigmatism, postoperative astigmatism, and SIA (P > .05 for all comparisons between Group 1 and Group 2). Conclusion Femtosecond laser–assisted and manual corneal incisions for cataract surgery did not appear to significantly alter corneal astigmatism, whereas they showed comparable SIA. Financial Disclosure Drs. Yoo and Donaldson are speakers for and consultants to Alcon Surgical, Inc., and Abbott Medical Optics, Inc. No other author has a financial or proprietary interest in any material or method mentioned.