Allon Barsam

Consultant Ophthalmologist,

OCL Vision, London, UK.ern Eye Hospital, Imperial NHS Trust.

https://www.oclvision.com

Latest Contribution

Diagram showing spherical aberration in post-refractive eyes.

Intraocular lens choice in patients who have undergone previous corneal refractive surgery

3 June 2026 | | EYE - Cataract, EYE - Cornea, EYE - Refractive

Patients who underwent vision correction in their 20s to 40s are now entering their 50s and 60s, the typical starting age for cataract development [1]. Consequently, ophthalmologists are increasingly encountering patients whose corneal profiles have been surgically altered, requiring advanced...

Image showing corneal topography following an outdated technique with small ablation zone hyperopic laser with a steepened central corneal and a small optical zone.

Surgical options for the treatment of hyperopia

1 August 2016 | | EYE - Cataract, EYE - Refractive

The modern refractive surgeon has a variety of options available to treat patients with hyperopia who wish to be independent of spectacles and contact lenses. Unlike in low myopia where presbyopic patients may have the ability to see well for...

Image showing visian implantable collamer lens.

Surgical treatment of high myopia

1 June 2016 | | EYE - Cataract, EYE - Refractive

Although several excellent modalities are available for correcting high myopia, the surgical treatment of this condition remains one of the biggest challenges for refractive surgeons; this group of patients is often very dependent on contact lenses. If these patients become...