Dumbbell technique for iridodialysis repair

Abstract

We describe a novel, simple and minimally invasive surgical technique for the repair of iridodialysis, which can be easily adopted by general ophthalmologists and cataract surgeons. Two eyes underwent this a new approach for iridodialysis repair using a 7-0 polypropylene (Prolene) suture. The 7-0 Prolene suture was used to pin the iris to the sclera, with a double flange resembling a dumbbell, one flange resting on the iris and the other on the sclera. With minimal instruments the technique was completed in a single surgical setting. Postoperative outcomes were favourable in both the cases, with improved visual acuity, near normal pupil contour and no hyphema. The technique was associated with minimal intraoperative time, good cosmetic outcomes and stable intraocular pressure. We conclude that this Dumb-Bell technique is a safe, simple, and efficient method for the repair of iridodialysis. It is minimally invasive with reduced risk of complications and can be readily performed by most ophthalmologists, including those with limited experience in complex iris repairs.

Iridodialysis, the detachment of the iris root from the ciliary body, is most commonly caused by ocular trauma or complicated intraocular surgery. It occurs when the globe is subjected to compressive forces that stretch the anterior segment structures, leading to separation at the iris root, which is the thinnest and weakest part of the iris stroma. Iridodialysis can also be a result of surgical manipulation during intraocular procedures.[1,2]

In cases of small iridodialysis (less than 2 clock hours), symptoms may be minimal, and no surgical intervention is required. However, larger iridodialysis can lead to significant visual disturbances, including the double-pupil effect, monocular diplopia, glare, and photophobia, which necessitate surgical repair.[2] Various surgical techniques have been described for the repair of iridodialysis, each with its own set of advantages and limitations.

Dr. Key proposed a technique of pinning the torn fibers of the iris section into the corneal substance at the iris angle by means of a Ziegler knife needle.[3] Ozdek introduced the “hang-back” technique where sutures are tied and the knot is left in the anterior chamber.[4] Hoffman described a method using MacCannel sutures through a scleral pocket for iridodialysis repair via an ab externo approach.[5] Khokhar et al.[6] reported a variation of the technique called the “Stroke and Dock” technique.

In this article, we present a novel approach for the repair of iridodialysis in a single surgical setting. Our technique is simple, safe, efficient, and preserves intraocular structures. It is easy to perform, uses only one Prolene suture, has a short learning curve, and can be readily adopted by most ophthalmologists, making it a valuable addition to the surgical armamentarium.

Case - 1

A 45-year-old male was referred to our hospital with iridodialysis and aphakia in the left eye following complicated cataract surgery. On slit-lamp examination, iridodialysis from 3 to 8 o’clock (5 clock hours) was noted [Fig. 1a], along with aphakia and an intact posterior capsule. The patient was advised to undergo secondary intraocular lens (IOL) implantation with repair of the iridodialysis under sub-Tenon’s anesthesia. Preoperative best corrected visual acuity (BCVA) was 6/18. Intraocular pressure (IOP) was within normal limits, and fundus examination was normal. The right eye was normal with a visual acuity of 6/6.

Figure 1.

(a) shows the extent of iridodialysis. (b) shows the eye and pupil after iridodialysis repair

Ab- Interno Approach [Video]

Routine steps of manual small incision cataract surgery were started, and a scleral incision of 6.5 mm was made, followed by the creation of a side port. Hydroxypropyl methylcellulose ophthalmic viscosurgical device (OVD) was injected into the anterior chamber. After making keratome entry, a three-piece IOL was implanted in the sulcus.

Conjunctival peritomy was done corresponding to the iridodialysis. Iris from 3 to 8 o’ clock was ironed out using a dispersive OVD. A 7-0 polypropylene suture with spatulated straight needle was introduced through the main incision, parallel to the iris, using a needle-holding forceps. The needle was then passed through the iris from anterior to posterior, directed to exit through the sclera approximately 1.5 mm from the limbus at the 6 o’clock position. The needle was then externalized with a needle holder. The suture was flanged at the proximal tip using a low-temperature cautery [Fig. 2a] and gently pulled so that the flanged tip was resting on the iris surface [Fig. 3b]. The exteriorized suture was cut, leaving a length of 1.5 cm. OVD was reinjected, and the same procedure was repeated for the suture to exit at the 7 o’clock, 3 o’clock, and 8 o’clock positions [Fig. 2b-f]. All sutures were then gently pulled and tightened [Fig. 3a,b]. Approximately 1.5 mm of suture was left in place at each site, and the distal tips were flanged at the scleral side using low-temperature cautery [Fig. 3c-f].

Figure 2.

(a-f) Ab-interno approach for iridodialysis repair

Figure 3.

(a-f) Internal and external flanging of Prolene suture

OVD was thoroughly aspirated from the anterior chamber using a Simcoe cannula, and the chamber was formed with balanced salt solution. Intracameral antibiotic (0.2 ml) was administered as a prophylaxis. The superior and inferior conjunctiva were apposed using a bipolar cautery to cover the scleral incision and the suture flanges, respectively [Fig. 1b].

Case -2

A 9-year-old male child presented with total traumatic cataract following firecracker injury in his right eye. Anterior segment examination also revealed posterior synechiae and 2 clock hours of iridodialysis from 9 to 11 o’clock [Fig. 4a]. Orthoptic evaluation showed 15-degree exotropia, which was reported to be there since birth. Although the iridodialysis was only 2 clock hours, we decided to repair it to avoid future possibility of photophobia, as the child was only 9 years old.

Figure 4.

(a) Preoperative traumatic cataract with iridodialysis. (b) Use of iris hooks to visualize the cataract. (c-f) Ab-externo approach of iris engagement

BCVA was 6/6 in the right eye and hand movements with accurate projection of rays in the left eye. B-scan was normal in the left eye.

Ab-Externo Approach

Temporal peritomy was done and lateral rectus muscle recession was performed to correct exotropia. A superior clear corneal incision was made, the anterior lens capsule was stained using trypan blue, and OVD was injected into the anterior chamber (AC). All posterior synechiae were released using a cyclodialysis spatula. Two side port entries were made corresponding to the area of iridodialysis, and iris hooks were used to maximize the visualization of the cataract. Capsulorrhexis was done, followed by lens aspiration using a Simcoe cannula. Posterior capsulorhexis was done, followed by minimal automated anterior vitrectomy. An acrylic IOL was implanted in the sulcus. Both iris hooks were then removed [Fig. 4b].

A 7-0 Prolene suture with spatulated straight needle was introduced 1.5 mm from the sclera at the 9 o’ clock position. The needle was advanced to pierce the iris from posterior to anterior, and counterpressure was applied from inside the eye using a 27-gauge OVD cannula [Fig. 4c-f] The needle was exteriorized at the 3 o’clock limbus. The needle was separated from the suture, which was hooked and pulled out with the help of a Kuglen’s hook introduced from the clear corneal incision [Fig. 5a]. The proximal end of the suture was flanged using low-temperature cautery [Fig. 5b and c]. The suture was gently pulled from the scleral side so that the flange rested on the iris, pulling the dialysis towards the iris root [Fig. 5d]. At about 2 mm from the limbus, the suture was cut at the scleral side and flanged to rest snuggly on the sclera [Fig. 5e and f]. OVD was aspirated, the anterior chamber was formed with BSS, and intracameral antibiotic (0.2 ml) was injected. The procedure was completed without complications.

Figure 5.

(a) Suture externalization using Kuglen’s hook. (b-d) Internal flange formation. (e, f) Formation of the external flange

Results

Postoperatively, both the patients showed satisfactory visual recovery (Case 1 BCVA 6/9, Case 2 BCVA 6/12), good cosmetic contour of the pupil, no hyphema, or any significant complications. IOP remained within normal limits.

Discussion

Minimizing ocular manipulation during surgery is crucial in managing traumatized eyes, as excessive handling can exacerbate intraocular damage and increase the risk of postoperative complications like prolonged inflammation, posterior synechiae, or peripheral anterior synechiae.

Repair of wide iridodialysis is particularly demanding and requires careful surgical planning.[1] In 2014, Kumar et al. described the “sewing machine” suture technique,[7] which has been well documented but carries significant risks, including the need for conjunctival dissection and the creation of long scleral tunnels, which can increase the likelihood of astigmatism and other complications. Additionally, repeated needle passes through the anterior chamber increase the risk of intraocular injury and suture slippage.[1,7]

In 2019, Kusaka et al.[8] described an approach similar to ours, using intrascleral fixation of a 6-0 polypropylene suture with a thermoplastic flange at the tip to secure the iris tissue. They used 27-guage and 30-guage needles, a 3 cm-sized 6-0 Prolene suture with one end pre- flanged using high-temperature cautery. In contrast, our technique does not require any extra needles or docking, uses a low-temperature cautery—which allows more controlled flanging—and no additional time to flange the suture end, making it a safer, less invasive, and less time-consuming option.

In recent years, there have been advancements in minimally invasive techniques for repairing iridodialysis, with a focus on reducing ocular manipulation and improving surgical outcomes. In 2022, Rosenberg et al.[9] introduced a knotless repair technique using a 6-0 Prolene suture, employing an ab-interno approach using a 27-gauge needle docked with the Prolene suture, introduced from the site opposite to the iridodialysis, inserted multiple times through the iris tissue, and finally flanged on the sclera. This method posed the risk of suture slippage, which could lead to complications and increased surgical time.

In 2023, Peng et al.[10] proposed a modified double-armed pre-flanged suture technique, drawing from the concept of flanged IOL fixation first described by Yamane et al.[11] This technique uses a 30-gauge needle to guide a 7-0 polypropylene suture, which is passed through the iris and exits the sclera. The absence of conjunctival dissection makes this method less invasive, and the suture can be repeatedly passed for extensive iridodialysis. Although effective, the need for precise placement of the suture and careful control of tension makes it a technique requiring significant skill.

In the same year, Ramakrishnan V. et al.[12] utilized an solely ab-externo approach with a 6-0 Prolene suture, double-flanged technique, which, although effective, still requires careful manipulation, suture docking into a 26G needle, and flanges on the scleral side, with the suture loop lying over the iris surface. In our technique, there is no need for needle docking; scleral puncture is done with the Prolene needle, which creates a much smaller aperture compared to a 26G needle, thus making it less traumatic to the sclera. It can be done using both ab-interno as well as ab-externo approaches.

In our first case, as the iridodialysis was in the inferior half (between 3 and 9 o’ clock), the ab-interno approach was used, and the suture was passed through the iris without the need for any extra needles like 26G, 27G, or 30G. The suture was then externalized 1.5 mm from the limbus, flanged into a knob of < 0.5 mm diameter, and tightened without the need for excessive tension, which was judged subjectively so as to bring the iris as close to the limbus as possible without cheese-wiring through the iris stroma. In the second case, as the dialysis was in the superior half (between 9 and 3 o’ clock), we used the ab-externo approach. Thus, we used both ab-interno as well as ab-externo approaches, and in both, the scleral ends of the flanged suture were covered with conjunctiva. As these knobs are smooth and atraumatic, the chances of conjunctival erosion are minimal. There was no incidence of suture or knob exposure, suture breakage, or conjunctival erosion noted in our cases over a 3-month follow-up period, which is one of the limitations in these two case reports.

Longer follow-ups are required to monitor any suture-related complications.

This method significantly reduces the time required for the procedure—no waiting time for extra needles or pre flanging—and minimizes complications such as suture slippage, iris prolapse, conjunctival erosion, knob exposure, or postoperative astigmatism, making it easier to perform even for ophthalmologists with limited experience in handling complex iris repairs. However, the only disadvantage is the need for low-temperature cautery, which might not be readily available.

This Dumbbell technique is also highly versatile, allowing for the repair of wide iridodialysis using a minimal number of instruments with reduced overall surgical time. Most importantly, the technique has proven to be safe, with no significant complications observed in either the perioperative or postoperative periods.

Conclusion

Our Dumbbell technique of iridodialysis repair is an easy, simple, minimally invasive, safe, and quick technique with a shorter learning curve and minimal instrumentation requirements, yielding a good cosmetic result postoperatively. It can be safely performed by all cataract surgeons aiming for not only visual but also cosmetic recovery.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Conflicts of interest:

There are no conflicts of interest.

Funding Statement

Nil.