Clinical papers & publications

In line with our strict clinical governance standards, Optical Express regularly publishes peer review articles, allowing all clinicians in the field to benefit from our knowledge and allowing us to give something back to the wider ophthalmological community.

Intraocular Lenses Papers

Incidence of Intraoperative and Early Postoperative Adverse Events in a Large Cohort of Consecutive Refractive Lens Exchange Procedures

Julie M. Schallhorn, Steven C. Schallhorn, David Teenan, Stephen J Hannan, Martina Pelouskova and Jan A. Venter | August 2019

To evaluate the incidence of adverse events (AEs) in patients who underwent refractive lens exchange.

RLE in Younger and Older Presbyopes

Steven C Schallhorn, Julie M Schallhorn, Martina Pelouskova, Jan A Venter, Keith A Hettinger, Stephen J Hannan, David Teenan | August 2017

A comprehensive analysis of Intraocular Lens/Cataract surgery outcomes performed at Optical Express using independence.

How presbyopes can benefit from the Tecnis Symfony lens

Stephen J Hannan | 2016

Stephen Hannan explains how the latest diffractive intraocular lens technology offers presbyopic patients high quality vision and spectacle independence with a look at the Tecnis Symfony lens.

Exploring advanced IOL technology for patients with presbyopia

Stephen J Hannan | May 2016

New extended range of vision IOLs offer high-quality vision to presbyopic patients, without side effects.

Advanced IOL Technology for Presbyopes

Stephen J Hannan | August 2016

A comprehensive analysis of Intraocular Lens/Cataract surgery outcomes performed at Optical Express using independence.

Technological Advances in Intraocular Lens Surgery – Femtosecond Laser-Assisted Cataract Surgery

Dasi Raju | July 2016

The Femtosecond laser–assisted cataract/ NLR surgery seems to be a safe, efficient, and reproducible procedure but more prospective randomized studies will further demonstrate the potential clinical benefits of this emerging technology.

Developments in Collagen Cross-Linking Technique

Mesha Tanna | June 2016

To list the function and development in Collagen Cross-Linking Techniques.

Outcomes of excimer laser enhancements in pseudophakic patients with multifocal intraocular lens

Steven C Schallhorn, Jan A Venter, David Teenan, Julie M Schallhorn, Keith A Hettinger, Stephen J Hannan, Martina Pelouskova | April 2016

The aim of this study was to assess visual and refractive outcomes of laser vision correction (LVC) to correct residual refraction after multifocal intraocular lens (IOL) implantation.

NHS comparison with Optical Express clinical outcomes - intraocular lens and cataract

Steven C. Schallhorn. MD | January 2016

Steve Schallhorn compares the results of an independently audited data analysis of Optical Expressintraocular lens and cataract outcomes with a recently published study of NHS cataract outcomes.

Visual acuity improvement in adult amblyopic eyes with an iris-fixated phakic intraocular lens: Long-term results

Jan A. Venter, MD, Martina Pelouskova, MSc, Steven C. Schallhorn, MD, Barrie M. Collins, Dip. Optom (SA), PhD | March 2015

To evaluate the effect of implantation of iris-fixated phakic intraocular lenses (pIOLs) (Artisan) in adult amblyopic eyes. The study analyzed data from 5 years of follow-up of amblyopic eyes that were implanted with iris-fixated pIOLs and had a preoperative corrected distance visual acuity (CDVA) of 6/15 or worse. Visual acuity, refraction, endothelial cell count, and complications were assessed.

Visual outcomes and patient satisfaction with a rotational asymmetric refractive intraocular lens for emmetropic presbyopia

Jan A. Venter, MD, Martina Pelouskova, MSc, Claire E.L. Bull, BSc, Steven C. Schallhorn, MD, Stephen J. Hannan, MCOptom | March 2015

To evaluate the efficacy, safety, predictability, and patient satisfaction after refractive lens exchange with a zonal refractive intraocular lens (IOL) with an inferior reading addition in emmetropic patients.

Piggyback Intraocular Lens Implantation to Correct Pseudophakic Refractive Error After Segmental Multifocal Intraocular Lens Implantation

Jan A. Venter, MD; Andre Oberholster, MD; Steven C. Schallhorn, MD; Martina Pelouskova, MSc | January 2014

To evaluate refractive and visual outcomes of secondary piggyback intraocular lens implantation in patients diagnosed as having residual ametropia following segmental multifocal lens implantation.

Visual outcomes and patient satisfaction in 9366 eyes using a refractive segmented multifocal intraocular lens

Jan A. Venter, MD, Martina Pelouskova, MSc, Barrie M. Collins, Dip.Optom (SA), PhD, Steven C. Schallhorn, MD, Stephen J. Hannan, MCOptom | October 2013

To report the effectiveness, patient satisfaction, and complication rate with a zonal refractive intraocular lens (IOL) in a high volume of patients.

Outcomes and complications of a multifocal toric intraocular lens with a surface-embedded near section

Jan Venter, MD, Martina Pelouskova | June 2013

To evaluate the refractive outcomes and rotational stability after implantation of a multifocal toric intraocular lens (IOL) with a surface-embedded near section.

Initial Experience With a New Refractive Rotationally Asymmetric Multifocal Intraocular Lens

Jan A. Venter, MD; Dean Barclay, MD; Martina Pelouskova, MSc; Claire E. L. Bull, BSc

To assess efficacy, safety, predictability, and patient satisfaction after refractive lens exchange with a new refractive rotational asymmetric multifocal intraocular lens.

Laser Eye Surgery Papers

Predictors of Patient Satisfaction After Refractive Lens Exchange With an Extended Depth of Focus IOL

Steven G. Schallhorn, MD; Keith A. Hettinger, MS; David Teenan, MD; Jan A. Venter, MD; Stephen J. Hannan, OD; Julie M. Schallhorn, MD | March 2020

To identify independent factors associated with postoperative satisfaction after refractive lens exchange with an extended depth of focus intraocular lens (EDOF IOL).

Incidence of Intraoperative and Early Postoperative Adverse Events in a Large Cohort of Consecutive Laser Vision Correction Treatments

Julie M. Schallhorn, Steven C. Schallhorn, David Teenan, Stephen J. Hannan, Martina Pelouskova, Jan A. Venter | December 2019

To evaluate the incidence of adverse events (AE) following laser vision correction.

Infectious keratitis after laser vision correction: Incidence and risk factors

Julie M. Schallhorn, MD, MS, Steven C. Schallhorn, MD, Keith Hettinger, MS, Stephen Hannan, OD | April 2017

To describe the incidence and risk factors associated with microbial keratitis in a large population of laser vision correction (LVC) patients.

Effectiveness of an Eyelid Thermal Pulsation Procedure to Treat Recalcitrant Dry Eye Symptoms After Laser Vision Correction

Craig S. Schallhorn, MD; Julie M. Schallhorn, MD; Stephen Hannan, OD; Steven C. Schallhorn, MD | 2017

To provide an initial retrospective evaluation of the effectiveness of a thermal pulsation system to treat intractable patient-reported dye eye symptoms following laser vision correction.

Technological Advances in Intraocular Lens Surgery – Femtosecond Laser-Assisted Cataract Surgery

Dasi Raju | August 2016

to describe how femtosecond laser-assisted cataract surgery is revolutionising the field

Developments in collagen cross-linking techniques

Mesha Tanna | October 2016

Reviewing the cornea, how it changes in disease and through ageing, and look at the technique of collagen cross-linking (C53856, one distance learning CET point for optometrists, contact lens opticians and therapeutic optometrists.)

Outcomes and complications of excimer laser surgery in patients with collagen vascular and other immune-mediated inflammatory diseases

Julie M. Schallhorn, MD, MS, Steven C. Schallhorn, MD, Keith A. Hettinger, MS, Jan A. Venter, MD, Martina Pelouskova, MSc, David Teenan, MD, Stephen J. Hannan, OD | December 2016

To assess refractive and visual outcomes and postoperative complications in a large number of patients with well-controlled collagen vascular and other immune-mediated inflammatory diseases.

Patient-reported outcomes 5 years after laser in situ keratomileusis

Steven C. Schallhorn, MD, Jan A. Venter, MD, David Teenan, MD, Stephen J. Hannan, OD, Keith A. Hettinger, MS, Martina Pelouskova, MSc, Julie M. Schallhorn, MD | June 2016

To assess vision-related, quality-of-life outcomes 5 years after laser in situ keratomileusis (LASIK) and determine factors predictive of patient satisfaction.

Monovision Approach to Presbyopia

Dasi Raju | December 2016

Presbyopia affects an estimated 10.4 billion people globally and, as eye care providers, we are faced with the daily challenge of finding the best solution for our presbyopic patients. There are numerous approaches to treat presbyopia, each has its own benefits and limitations.

Flap-related infections

Steven Schallhorn, MD | April 2016

Corneal infection after creation of a lamellar ap is a potentially devastating complication of LASIK. As demonstrated by the steadily falling number of infectious keratitis cases following corneal refractive surgery, the risk of infection can be reduced through surgical technique, increased awareness, and proper prophylaxis.

Optical Express Case Study: Options of refractive surgery

Mesha Tanna | March 2016

Mesha Tanna describes a case study involving a young lawyer who wanted to stop wearing contact lenses due to lifestyle factors, demonstrating the effectiveness of iDesign Intralase Lasik.

iDesign to treat mod to high astigmatism

Jan A Venter, Steven C Schallhorn, MD, MS, MD, Keith Hettinger, MS, Stephen Hannan, OD | July 2015

To describe the incidence and risk factors associated with microbial keratitis in a large population of laser vision correction (LVC) patients.

Flap lift and photorefractive keratectomy enhancements after primary laser in situ keratomileusis using a wavefront-guided ablation profile: Refractive and visual outcomes

Steven C. Schallhorn, MD, Jan A. Venter, MD, Stephen J. Hannan, OD, Keith A. Hettinger, MS, David Teenan, MD | November 2015

To analyze results of wavefront-guided laser vision correction retreatments performed either by lifting the original flap or by surface ablation over the flap.

Outcomes of wavefront-guided laser in situ keratomileusis using a new-generation Hartmann-Shack aberrometer in patients with high myopia

Steven C. Schallhorn, MD, Jan A. Venter, MD, Stephen J. Hannan, OD, Keith A. Hettinger, MS | September 2015

To evaluate refractive and visual outcomes of wavefront-guided laser in situ keratomileusis (LASIK) to correct high myopia using a new Hartmann-Shack aberrometer.

Effect of postoperative keratometry on quality of vision in the postoperative period after myopic wavefront-guided laser in situ keratomileusis

Steven C. Schallhorn, MD, Jan A. Venter, MD, Stephen J. Hannan, OD, Keith A. Hettinger, MS, David Teenan, MD | December 2015

To determine whether postoperative keratometry is a predictor of patient-reported satisfaction and night-vision phenomena after wavefront-guided myopic laser in situ keratomileusis (LASIK).

Outcomes of wavefront guided laser in situ keratomileusis using a new generation Hartmann Shack aberrometer

Steven C. Schallhorn, MD, Jan A. Venter, MD, Stephen J. Hannan, OD, Keith A. Hettinger, MS | September 2015

To evaluate refractive and visual outcomes of wavefront-guided laser in situ keratomileusis (LASIK) to correct high myopia using a new Hartmann-Shack aberrometer.

Factors that Influence Intraocular Pressure Changes after Myopic and Hyperopic LASIK and Photorefractive Keratectomy

Julie M. Schallhorn, MD, MS, Steven C. Schallhorn, MD, Yvonne Ou | March 2015

To describe the factors that influence the measured intraocular pressure (IOP) change and to develop a predictive model after myopic and hyperopic LASIK and photorefractive keratectomy (PRK) in a large population. The Optical Express database was queried for all subjects. Data were extracted on procedure specifics, preoperative central corneal thickness (CCT), IOP (using noncontact tonometry), manifest refraction, average keratometry, age, gender, and postoperative IOP at 1 week, 1 month, and 3 months. A linear mixed methods model was used for data analysis.

Clinical outcomes of wavefront-guided laser in situ keratomileusis to treat moderate-to-high astigmatism

Steven C Schallhorn, Jan A Venter, Stephen J Hannan, Keith A Hettinger | 13th July 2015

The purpose of this study was to evaluate the refractive and visual outcomes of wavefront-guided laser in situ keratomileusis (LASIK) in eyes with myopic astigmatism and cylindrical component 2.0 diopter (D).

Factors that Influence Intraocular Pressure Changes after Myopic and Hyperopic LASIK and Photorefractive Keratectomy

Julie M. Schallhorn, MD, MS, Steven C. Schallhorn, MD, Yvonne Ou | March 2015

To describe the factors that influence the measured intraocular pressure (IOP) change and to develop a predictive model after myopic and hyperopic LASIK and photorefractive keratectomy (PRK) in a large population. The Optical Express database was queried for all subjects. Data were extracted on procedure specifics, preoperative central corneal thickness (CCT), IOP (using noncontact tonometry), manifest refraction, average keratometry, age, gender, and postoperative IOP at 1 week, 1 month, and 3 months. A linear mixed methods model was used for data analysis.

Wavefront-Guided Photorefractive Keratectomy with the Use of a New Hartmann-Shack Aberrometer in Patients with Myopia and Compound Myopic Astigmatism

Steven C. Schallhorn, Jan A. Venter, Stephen J. Hannan, and Keith A. Hettinger | April 2015; revised July 2015

To assess refractive and visual outcomes and patient satisfaction of wavefront-guided photorefractive keratectomy (PRK) in eyes with myopia and compound myopic astigmatism, with the ablation profile derived from a new Hartmann-Shack aberrometer.

To report the outcomes of the correction of mixed astigmatism with non-penetrating femtosecond laser intrastromal astigmatic keratotomy in patients with previous refractive surgery.

Steven Schallhorn, MD; Mitch Brown, OD; Jan Venter, MD; Keith Hettinger, MS; Stephen Hannan, OD | November 2013

To determine the relationship between lowlight pupil size and patient-reported outcomes 1 month after wavefront-guided LASIK in young patients with myopia.

The Role of the Mesopic Pupil on Patient-Reported Outcomes in Young Patients With Myopia 1 Month After Wavefront-Guided LASIK

Steven Schallhorn, MD; Mitch Brown, OD; Jan Venter, MD; Keith Hettinger, MS; Stephen Hannan, OD | November 2013

To determine the relationship between lowlight pupil size and patient-reported outcomes 1 month after wavefront-guided LASIK in young patients with myopia.

The Effect of Procedure Room Temperature and Humidity on LASIK Outcomes

Michael I. Seider, MD, Stephen D. McLeod, MD, Travis C. Porco, PhD, MPH, Steven C. Schallhorn, MDlens_anchor | March 2013

To determine whether procedure room temperature or humidity during LASIK affect refractive outcomes in a large patient sample.

Early Clinical Outcomes of Wavefront-Guided Myopic LASIK Treatments Using a New-Generation Hartmann-Shack Aberrometer

Steven Schallhorn, MD; Mitch Brown, OD; Jan Venter, MD; David Teenan, FRCS(Ed), FRCOphth; Keith Hettinger, MS; Hiromi Yamamoto, BS | August 2013

To provide an initial retrospective evaluation of early postoperative outcomes after wavefront-guided myopic LASIK using a new-generation Hartmann-Shack wavefront sensor.

Non-penetrating Femtosecond Laser Intrastromal Astigmatic Keratotomy in Patients With Mixed Astigmatism After Previous Refractive Surgery

Jan Venter, MD; Rodney Blumenfeld, MD; Steve Schallhorn, MD; Martina Pelouskova, MSc | December 2012

To report the outcomes of the correction of mixed astigmatism with non-penetrating femtosecond laser intrastromal astigmatic keratotomy in patients with previous refractive surgery.

Non-penetrating Femtosecond Laser Intrastromal Astigmatic Keratotomy in Patients With Mixed Astigmatism After Previous Refractive Surgery

Jan Venter, MD; Rodney Blumenfeld, MD; Steve Schallhorn, MD; Martina Pelouskova, MSc | December 2012

To report the outcomes of the correction of mixed astigmatism with non-penetrating femtosecond laser intrastromal astigmatic keratotomy in patients with previous refractive surgery.

Early Flap Displacement after LASIK

Gerry Clare, FRCOphth, Tara C. B. Moore, PhD, Claire Grills, PhD, Antonio Leccisotti, MD, PhD, Johnny E. Moore, FRCOphth, PhD, Steve Schallhorn, MD | September 2011

To evaluate the risks of flap displacement after LASIK.

2010 Laser Vision Correction: Using Biostatistics to Revolutionise Refractive Surgery Outcomes

H Burkhard Dick, MD; Mitchell C. Brown, OD; Steven C. Schallhorn, MD; Joseph Colin, MD; Keith A. Hettinger, MS, MBA; John A. Vukich, MD | April 2010

In these pages, you’ll read more from statistician Keith Hettinger on the power of – and inherent challenges in – large data sets, and how practices can use their own data to improve outcomes. We’ll also hear from Steve Schallhorn MD, about the excellent results in low and moderate myopes – and how those results can be duplicated in clinical practice.

One-month Outcomes of Wavefront-guided LASIK for Low to Moderate Myopia With the VISX STAR S4 Laser in 32,569 Eyes

Steven C. Schallhorn, MD; Jan A. Venter, MD | July 2009

To determine the safety and efficiency of wavefront-guided LASIK for the correction of low to moderate myopia, as performed by surgeons employed by Optical Express, a large corporate provider.

Femtosecond Laser Versus Mechanical Microkeratome: A Retrospective Comparison of Visual Outcomes at 3 Months

Mesha Tanna, BSc(Hons), MCOptom; Steven C. Schallhorn, MD; Keith A. Hettinger, MS, MBA | July 2009

To compare the visual outcomes of LASIK procedures in which fl aps were created with a femtosecond laser (IntraLase FS 60Hz, Abbott Medical Optics [AMO]) to procedures in which flaps were created with a mechanical microkeratome (Moria Evo3 One Use-Plus, Moria SA).

Effect of Keratometry on Visual Outcomes 1 Month After Hyperopic LASIK

Jill J. Young, BSc(Hons), MCOptom; Steven C. Schallhorn, MD; Mitchell C. Brown, OD; Keith A. Hettinger, MS, MBA | July 2009

To determine whether preoperative, postoperative, or change in keratometry can be used to predict visual outcomes in hyperopic LASIK.

An Evidence-based Approach to Patient Selection for Laser Vision Correction

Mitchell C. Brown, OD | July 2009

To describe the process used by Optical Express, a large corporate refractive surgery provider, to develop evidence-based patient selection guidelines for laser vision correction.

Satisfaction of 13,655 Patients With Laser Vision Correction at 1 Month After Surgery

Mitchell C. Brown, OD; Steven C. Schallhorn, MD; Keith A. Hettinger, MS, MBA; Stephanie E. Malady, BS | July 2009

To assess the level of laser vision correction patient satisfaction achieved by a large corporate provider of refractive surgery.

General Papers

Effect of Gender and Procedure on Patient- Reported Dry Eye Symptoms After Laser Vision Correction

Julie M. Schallhorn, MD, MS; Martina Pelouskova, MSc; Catherine Oldenburg, PhD; David Teenan, MD; Stephen J. Hannan, OD; Steven C. Schallhorn, MD | January 2019

This paper evaluates factors associated with the change in dry eye symptoms following Laser Vision Correction. The restrospective analysis considered 13,319 patients that underwent either LASIK or PRK (LASEK).

Informed consent in refractive surgery: in-person vs telemedicine approach

Steven C Schallhorn; Stephen J Hannan; David Teenan; Julie M Schallhorn | November 2018

The aim of this study was to compare the quality of consent process in refractive surgery between patients who had a preoperative consent discussion with the surgeon using a telemedicine approach and those who had a face-to-face discussion.

Monovision LASIK Versus Presbyopia: Correcting IOLs: Comparison of Clinical and Patient-Reported Outcomes

Steven C. Schallhorn, MD; David Teenan, MD; Jan A. Venter, MD; Julie M. Schallhorn, MD, MS; Keith A. Hettinger, MS; Stephen J. Hannan, OD; Martina Pelouskova, MSc | November 2017

To compare clinical and quality of life out ABSTRACT – T comes between patients who underwent monovision LASIK and refractive lens exchange.

Monovision LASIK in emmetropic presbyopic patients

Steven C. Schallhorn, MD; David Teenan, MD; Jan A. Venter, MD; Julie M. Schallhorn, MD, MS; Keith A. Hettinger, MS; Stephen J. Hannan, OD; Martina Pelouskova, MSc | November 2017

To evaluate the efficacy and patient satisfaction of laser in situ keratomileusis (LASIK) monovision correction in presbyopic emmetropic patients.

Role of the treating surgeon in the consent process for elective refractive surgery

Steven C Schallhorn; Stephen J Hannan; David Teenan; Julie M Schallhorn | November 2016

To compare patient’s perception of consent quality, clinical and quality-of-life outcomes after laser vision correction (LVC) and refractive lens exchange (RLE) between patients who met their treating surgeon prior to the day of surgery (PDOS) or on the day of surgery (DOS).

Using an International Medical Advisory Board to Guide Clinical Governance in a Corporate Refractive Surgery Model

John A. Vukich, MD | July 2009

To describe the role played by the International Medical Advisory Board (IMAB) in clinical and corporate governance at Optical Express, a corporate provider of refractive surgery.

The Role of Biostatistics in the Quality Improvement of Refractive Surgery

Keith A. Hettinger, MS, MBA | July 2009

To demonstrate how the large quantity of uniformly collected data available to a corporate refractive surgery provider, Optical Express, is applied to drive improvements in patient outcomes.

A Complex Case Management System Provides Optimal Care for All Patients

Jan A. Venter, MD; Stephen J. Hannan, MCOptom | July 2009

To describe the complex case management system developed by Optical Express, a large corporate provider of laser vision correction, and to detail the benefits this system offers for managing the surgical complications of laser vision correction.

Julie M. Schallhorn, Steven C. Schallhorn, David Teenan, Stephen J. Hannan, Martina Pelouskova, Jan A. Venter | December 2019

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