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A easy, efficient various to corneal transplantation


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July 10, 2025

12 min learn

Key takeaways:

  • Pinhole pupilloplasty might assist mitigate the worldwide scarcity of donor corneas.
  • The process additionally has indications for irregular astigmatism and higher-order aberrations ensuing from keratoconus.

Pinhole pupilloplasty is an easy and low-cost resolution to revive imaginative and prescient in sufferers with extremely aberrated corneas and could be a legitimate various to corneal transplantation.

“This new utility makes it crucial given the scarcity of donor corneas on the planet. Even the place donor corneas can be found, keratoplasty stays a troublesome process with a excessive price of problems, sluggish restoration, unsure outcomes and a excessive price of rejection,” Amar Agarwal, MS, FRCS, FRCOphth, mentioned.



“This new application makes it very important given the shortage of donor corneas in the world.” - Amar Agarwal, MS, FRCS, FRCOphth

Picture: Courtesy of Dr. Agarwal’s Eye Hospital

Pinhole pupilloplasty (PPP) is a process that Agarwal developed a number of years in the past, and it has regularly gained consensus amongst cornea specialists worldwide. It’s primarily based on the identical precept of pinhole optics utilized in particular IOLs: The small aperture acts as a wavefront filter, blocking the peripheral distorted and unfocused mild rays whereas directing the extra centered central rays by way of the aperture. This leads to vital discount of higher-order aberrations, elevated depth of focus and improved high quality of imaginative and prescient.

As in contrast with small-aperture IOLs, PPP customizes the pinhole optic impact additional, providing a definite benefit.

“In some instances, it may be the one methodology to regain sight, instantly bringing the affected person again from counting fingers to twenty/20 imaginative and prescient,” Agarwal mentioned.

An advantageous various to keratoplasty

In 2016, a worldwide survey on corneal transplantation and eye banking quantified the numerous scarcity of corneal graft tissue, with just one cornea obtainable for each 70 wanted. Right now, the donor-recipient measurement mismatch continues to be alarmingly broad, significantly in international locations the place the magnitude of corneal blindness is best.

“As well as, you want specialised surgeons for corneal transplantation, and the outcomes aren’t all the time the perfect. You may need astigmatism, corneal scarring and rejection after penetrating keratoplasty. So, now we have began now to suggest pinhole pupilloplasty as an alternative in lots of of those sufferers,” Agarwal mentioned.

He talked about the case of a 14-year-old boy who had a scarred cornea resulting from a knife damage and a subluxated lens from a earlier intervention by one other surgeon.

“We did glued IOL surgical procedure and pupilloplasty, and the boy was instantly in a position to see 20/30 and J2,” Agarwal mentioned. “Had I carried out penetrating keratoplasty, he would have needed to wait 3 to six months to get better, and the visible outcomes wouldn’t have been sure.”

PPP avoids the trauma, unsure outcomes and problems of extra invasive interventions, bypassing points associated to corneal irregularities by permitting mild to cross by way of part of the cornea that’s free from distortion.

“Suppose there’s a scar; I’ll make the pinhole barely away from the scar. Suppose there’s astigmatism; I don’t change it, it’s nonetheless there, however I neutralize it by blocking out the irregular components of the cornea,” Agarwal mentioned. “We don’t want any nomogram in PPP. Regardless of the astigmatism or higher-order aberrations, pinhole pupilloplasty neutralizes them.”

There may be additionally a bonus when it comes to value.

“What’s the value to the surgeon? The surgeon wants solely a Prolene suture. That’s all,” he mentioned.

Pupil measurement and placement

A pinhole pupil gauge (Epsilon), designed by Jack T. Holladay, MD, MSEE, is an indispensable device for all surgeons who carry out PPP.

Jack Holloway

Jack T. Holladay

“I joined the crew of Amar Agarwal about 10 years in the past as an optics skilled to design an instrument they might use to foretell what pinhole measurement could be the perfect for the affected person. Since then, I’ve been concerned of their research and really feel very privileged to have labored with them,” Holladay mentioned.

The system consists of an opaque disc with pinholes at totally different diameters, from 0.5 mm to 4 mm. It’s positioned in entrance of the attention and rotated till the affected person finds the outlet measurement that gives the perfect imaginative and prescient, measured on a normal Snellen chart.

“This little gauge I made permits us to find out for a particular affected person which pupil measurement is the perfect earlier than we go to surgical procedure,” Holladay mentioned. “Sufferers with gentle irregularity are going to see fairly properly with a 1.5-mm or 2-mm pupil, but when they’ve a extreme scar and irregular cornea, they may want a 1-mm or 0.5-mm pinhole.”

The placement of the pinhole pupil additionally must be decided, relying on the place the corneal scar is positioned.

“We will take a look at the topography and see in what zones of the cornea the irregularity is essentially the most extreme and in what different components it’s not so extreme,” Holladay mentioned. “Based mostly on this, we are able to decide the placement of the pinhole, aligning it with the perfect a part of the cornea to get the perfect imaginative and prescient.”

The pinole pupil gauge contributes to this location willpower.

“Let’s say a affected person has a scar within the decrease a part of the cornea,” he mentioned. “After they look by way of the 1-mm pupil in entrance of that space, they don’t see very properly, but when I transfer that 1-mm pinhole as much as the highest of the cornea they usually see properly, then I do know that I have to make that pupilloplasty in order that the pupil is within the higher a part of the cornea to get the perfect imaginative and prescient.”

A number of indications

PPP has many potential indications together with excessive irregular astigmatism and higher-order aberrations ensuing from keratoconus, pellucid marginal degeneration, radial keratotomy, deep anterior lamellar keratoplasty or penetrating keratoplasty, in addition to corneal scars induced by accidents or infections.

Like Agarwal, Holladay sees PPP as an easier and sooner various to corneal transplantation.

“In some sufferers with irregularities, we might robotically do a corneal transplant to get a greater cornea, after which it’s a must to wait 6 months to 1 yr to take away the sutures,” Holladay mentioned. “With PPP, you place the pinhole the place they’ve the perfect corneal optics, make it the scale of about 1 mm, and sufferers don’t want that lengthy interval of therapeutic and adjustment earlier than they really can see.”

In lots of instances, pupilloplasty could also be required anyway after corneal transplantation as a result of astigmatism and corneal aberrations are a typical complication of transplantation, Holladay mentioned. “So, you may as properly do PPP as an alternative.”

“I’m now working on many sufferers with corneal scars, corneal accidents, keratoconus, sufferers posted for DALK and sufferers posted for PK during which we’re in a position to do pinhole pupilloplasty as an alternative,” Agarwal mentioned.

Closed-angle glaucoma can be a sign.

“I pull the iris down and make a pinhole, the angle opens up, and the strain goes down instantly,” Agarwal mentioned.

In a affected person who had Intacs (Addition Expertise) for keratoconus and developed a corneal opacity and vascularization, Agarwal was in a position to keep away from transplantation by performing PPP.

“Importantly, if sufferers are phakic, it’s a must to make them pseudophakic as a result of you may hit the lens when you find yourself doing the surgical procedure,” he mentioned.

As a result of many of those sufferers are more likely to have some extent of lens opacification, implanting an IOL may additional enhance the outcomes of pupilloplasty and keep away from the inconvenience of getting the pupilloplasty reversed when cataract surgical procedure is required.

Surgical methods

Agarwal and Priya Narang, MS, developed the basic single-pass four-throw (SFT) pupilloplasty method.

The iris is held with forceps launched by way of a distal stab incision, and a 9-0 or 10-0 polypropylene suture is handed with a protracted straight needle from a proximal clear corneal incision by way of the iris tissue alongside the sting of the pupil. From the distal incision, a 26-gauge needle is launched, and the primary needle is handed into the 26-gauge lumen of the second needle and pulled, dragging the suture by way of the iris. Utilizing a hook, a loop of suture is withdrawn from the distal incision, and the distal suture finish is handed 4 occasions by way of the loop. Lastly, each ends of the suture are pulled in reverse instructions. The pupil is now narrowed on one aspect, and the suture ends are lower with micro-scissors. The identical process is repeated on the reverse aspect.

“To precisely place the pinhole pupil on the middle of the visible axis, ensure that the Purkinje picture P1 is on the middle of the pupil,” Agarwal mentioned.

If the pupil finally ends up being too small, it may be enlarged on the finish of the surgical procedure with a vitrectomy probe to attain the scale that was deliberate preoperatively.

Jack S. Parker, MD, PhD, has been utilizing PPP for a number of years in sufferers with corneal irregularities corresponding to scars from prior procedures together with RK or PK.

Parker Jack_2018 80x106

Jack S. Parker

“These individuals can typically enhance their imaginative and prescient solely by sporting arduous contact lenses however discover them uncomfortable or inconvenient. You’ll be able to enhance their high quality of imaginative and prescient by doing pinhole pupilloplasty,” he mentioned.

Parker’s surgical method is barely totally different from the unique SFT method. He passes the needle with the suture from a proximal wound into the attention and makes use of a curved needle moderately than a straight one.

“I scoop down and seize the iris with the curved needle after which cross it immediately out by way of the cornea distally,” Parker mentioned. “The benefit of doing that’s that it doesn’t require any intraocular forceps to seize and maintain the iris, nor the docking of two needles inside the attention. It’s a one-handed method that requires much less guide dexterity. It’s easier and sooner for me to do than the unique SFT method.”

Titratable, adjustable, customizable

Some years in the past, Ahmed Assaf, MD, PhD, used the XtraFocus pinhole implant (Morcher) in round 15 sufferers with extreme corneal scars, ruptured globes and irregular corneas after RK.

“I had pretty good outcomes, however the problem with this kind of lens is that we can not management centration,” Assaf mentioned. “The place relies on the anatomy of the sulcus, and typically the pinhole stays in entrance of the visible axis, however typically it stays away from it, and we get suboptimal outcomes. So, when Agarwal revealed his collection of pinhole pupilloplasty I believed it was a good suggestion as a result of we are able to place the pinhole impact simply in entrance of the visible axis.”

The opposite benefit he noticed was the fee. Pinhole lenses are costly, whereas PPP wants solely a skinny Prolene suture and has extra constant outcomes.

Assaf makes use of PPP in sufferers with earlier RK who used to stay with irregular corneas and now have an possibility for regaining good sight.

“We will do cataract surgical procedure after which pupilloplasty, and the outcomes are marvelous for these sufferers,” he mentioned.

He additionally makes use of it in sufferers with superior keratoconus so long as there isn’t a central opacity within the cornea and the cone is steady.

“We will enhance imaginative and prescient with out the necessity for penetrating keratoplasty, which is pricey and has unpredictable outcomes and a excessive price of rejection,” Assaf mentioned. “Particularly in younger sufferers, I keep away from transplantation and like to do PPP. I take a number of measurements over at the least 1.5 years to ensure that the cornea is steady. If it’s not, I carry out cross-linking, proceed to observe the affected person till I’m positive that the illness is not progressing, after which I do pupilloplasty.”

In Assaf’s space in Egypt, there’s a scarcity of donor corneas, and when they’re obtainable, the fee is excessive and never fully coated by insurance coverage. Sufferers need to pay out of pocket in some instances, and there’s a lengthy ready record of 6 months or extra.

To date, Assaf has handled about 25 sufferers with PPP and located that outcomes have been considerably higher in contrast with pinhole lenses.

The higher outcomes are resulting from “the scale of the pupil, which we are able to customise, and the placement alongside the visible axis, which we are able to establish by the primary Purkinje picture throughout surgical procedure,” he mentioned.

Assaf makes use of the Holladay pupil measuring system and mentioned that the majority of his sufferers select a pupil of two mm to 2.5 mm. Throughout surgical procedure carried out with the SFT method, in some instances, he may shut the entire pupil after which create a brand new small pupil with a vitreous cutter alongside the primary Purkinje reflex. Every time attainable, he performs pupilloplasty in just one eye, and that is greater than sufficient to enhance visible outcomes and life-style, he mentioned.

“I are inclined to make the pupil barely smaller than the supposed measurement after which take a look at the sufferers. If they don’t seem to be glad, I can barely enlarge the pupil by YAG laser, which is an ingenious concept that Dr. Agarwal has not too long ago revealed,” Assaf mentioned.

YAG after surgical procedure

Agarwal beforehand urged that Nd:YAG laser can be utilized to undo pupilloplasty when wanted. A contact of YAG may also be a manner of titrating the pinhole after surgical procedure.

“Suppose you made the pupil too small by mistake, let’s say 0.5 mm as an alternative of 1.5 mm. All you do is take a YAG laser and simply shoot the iris to make it bigger,” Agarwal mentioned.

The identical might be carried out if sufferers aren’t totally glad because of the lower in retinal luminance ranges.

“Only a few sufferers of mine say they’re seeing 20/20 however the illumination is just too low,” Agarwal mentioned. “I enlarge the pupil somewhat bit by YAG laser utilizing 2 mJ to 4 mJ, shoot a small burst on the iris, and the affected person’s illumination downside is solved.”

Parker additionally makes use of a YAG laser to enlarge the pinhole if wanted, making use of it to both the sutures or the pupillary opening itself.

“That’s actually fast, straightforward to do and really managed,” Parker mentioned. “Once I do the surgical procedure, I sometimes err on the small aspect as a result of it’s straightforward to enlarge the pupil within the workplace with the laser. If it’s too large, it’s a must to return to the OR and put extra sutures in.”

Small trade-offs for a excessive acquire

Issues with scotopic imaginative and prescient are primarily reported by the few sufferers who’ve pinhole pupilloplasty in each eyes.

“In case you have a 1-mm pinhole in each eyes and also you stand up in the course of the night time to go to the toilet, every thing is black,” Holladay mentioned. “You may have misplaced your scotopic imaginative and prescient as a result of that pinhole doesn’t let sufficient mild in.”

Nevertheless, the issue might be simply solved by maintaining a flashlight or penlight close to the mattress. It’s a good trade-off for the development in on a regular basis all-around imaginative and prescient, he mentioned.

“The miracle of going from depend fingers to twenty/30 is value that small sacrifice of scotopic imaginative and prescient since you go from being legally blind to have the ability to drive a automobile,” Holladay mentioned.

One other trade-off is {that a} pinhole pupil limits visualization of the periphery of the retina. Nevertheless, that is much less of an issue with fashionable fundus cameras, in line with Parker.

“In case you have a affected person who has 20/200 or 20/400 imaginative and prescient who may probably be 20/40 with a pinhole, and also you say, ‘No, Ms. Jones, we are able to’t do the process as a result of in the future sooner or later I may need issues seeing the again of your eye, so it’s a must to keep legally blind,’ the argument breaks down instantly,” he mentioned. “The theoretical chance of lacking a retinal downside does exist, however I’ve by no means had a affected person inform me they’d spend the remainder of their life not having the ability to see due to the potential of a retinal downside that may not be visualized.”

There could also be beauty considerations because of the altered pupil form and measurement, however this additionally turns into a suitable compromise for sufferers who’ve low imaginative and prescient and no different therapeutic possibility.

“Sufferers with a light-colored iris will discover a distinction within the measurement of the pupil, small in a single eye and bigger and dynamic within the different eye,” Assaf mentioned. “We now have to debate this with the affected person preoperatively. In my space, we’re privileged as a result of the general public have darkish brown eyes.”

Assaf strongly advisable that his colleagues do this method as a result of it’s straightforward and low value and leads to glad sufferers.

“A number of the sufferers are coming for a second opinion on penetrating keratoplasty and have already calculated the expense of the surgical procedure,” he mentioned. “Once I provide them one other resolution — dwelling with their very own cornea, avoiding the chance of graft rejection, and having a shorter restoration time and decrease value — they gladly embrace the chance and are fairly glad and glad after surgical procedure.”

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For extra info:

Amar Agarwal, MS, FRCS, FRCOphth, director of Dr. Agarwal’s Eye Hospital and Eye Analysis Centre, India, might be reached at aehl19c@gmail.com.

Ahmed Assaf, MD, PhD, professor of ophthalmology at Ain Shams College, Cairo, might be reached at assaf.ahmed@gmail.com.

Jack T. Holladay, MD, MSEE, medical professor at Baylor Faculty of Drugs, Houston, might be reached at holladay@docholladay.com.

Jack S. Parker, MD, PhD, of Parker Cornea in Vestavia Hills, Alabama, might be reached at jack.parker@gmail.com.