|Year : 2022 | Volume
| Issue : 1 | Page : 81-83
Cataract following Nd:YAG peripheral iridotomy in a case of phakic intraocular lens implantation
Praveen Subudhi1, Sweta Patro2, Silla Sitaram2, B N R Subudhi2
1 Department of Refractive Surgery, Ruby Eye Hospital, Govinda Vihar, Berhampur; Department of Refractive Surgery, Hitech Medical College, Bhubaneswar, Odisha, India
2 Department of Refractive Surgery, Ruby Eye Hospital, Govinda Vihar, Berhampur, Odisha, India
|Date of Submission||14-Jul-2021|
|Date of Acceptance||30-Aug-2021|
|Date of Web Publication||07-Jan-2022|
Dr. Praveen Subudhi
Ruby Eye Hospital, Govinda Vihar, Berhampur, Ganjam - 760 001, Odisha
Source of Support: None, Conflict of Interest: None
A 27-year-old female presented with defective vision in her right eye for the past 6 months. Her presenting visual acuity was 4/60. She had a history of axial myopia since childhood. She underwent Phakic IOL surgery 3 years prior. On clinical examination, there was a patent peripheral iridotomy with an underlying focal anterior capsular and a subcapsular cataract with a posterior subcapsular component. She was scheduled for removal of the phakic IOL and phacoemulsification of the cataractous lens with implantation of a multipiece monofocal lens. The postoperative UDVA was 6/9, and the near visual acuity was N8. The patient had persistent good vision for the first postoperative year.
Keywords: Nd:YAG peripheral iridotomy, posterior subcapsular cataract, RIL
|How to cite this article:|
Subudhi P, Patro S, Sitaram S, Subudhi B N. Cataract following Nd:YAG peripheral iridotomy in a case of phakic intraocular lens implantation. Indian J Ophthalmol Case Rep 2022;2:81-3
|How to cite this URL:|
Subudhi P, Patro S, Sitaram S, Subudhi B N. Cataract following Nd:YAG peripheral iridotomy in a case of phakic intraocular lens implantation. Indian J Ophthalmol Case Rep [serial online] 2022 [cited 2022 Jan 23];2:81-3. Available from: https://www.ijoreports.in/text.asp?2022/2/1/81/334911
Refractive surgery has evolved exponentially in the past two decades. The basic aim of any refractive surgery is to provide spectacle-free vision and long-term persistent results. Keratorefractive surgeries are avoided in patients with poor corneal biomechanics. Phakic intraocular lenses are a very viable alternative to refractive surgery that can provide spectacle-free vision to high refractive errors and refractive errors with suspicious corneas. Posterior chamber phakic intraocular lenses (pIOLs) have two variants: one with a central hole and the other without a central hole. Posterior chamber phakic IOLs (pIOLs) without a central hole require Nd:YAG peripheral iridotomy to be performed to prevent any form of angle-closure attack. Peripheral iridotomy by Nd:YAG lasers should be carefully performed to prevent any accidental damage to crystalline lenses. Here, we report a case of posterior chamber phakic IOL implantation for high myopia in which the patient developed cataracts following accidental damage to the anterior lens capsule with a Nd:YAG laser.
| Case Report|| |
A 27-year-old female came to our hospital with complaints of defective vision in both eyes for 15 years. She presented with uncorrected visual acuity of 2/60 in both eyes (BE), which improved to 6/6p with −9.5D spherical correction. On clinical evaluation, she was diagnosed with axial myopia in BE with no evidence of amblyopia. She was evaluated for refractive surgical correction. Her pentacam images revealed a corneal thickness of <500 microns. Her anterior chamber depth from the corneal endothelium was 3.50 mm. Her Belin Ambrosio enhanced ectasia reports showed normal anterior and posterior floats with no evidence of any red flags. Her refractive error was stable and she was scheduled to receive refractive intraocular lenses (RILs) from Appasamy Associates Inc. Customized RILs were calculated using subjective refraction and white-to-white diameter.
Nd:YAG peripheral iridotomy (PI)
Peripheral iridotomy was performed using a Nd:YAG laser (Zeiss Visulas, Inc.) and an Abraham contact lens. A treatment site was chosen in the superior iris in a crypt where present. Single 5–6-mJ pulses of energy were delivered to the treatment site repeatedly until patency was achieved. The total amount of energy used was undetermined. Patency was determined by direct visualization of a red glow by means of the retroillumination method.
Surgical implantation of RILs
The patient underwent bilateral uneventful implantation of RILs with a good postoperative visual outcome. The postoperative vault height as determined by ASOCT was 489 microns in the right eye (RE) and 495 microns in the left eye (LE). Her unaided visual acuity was 6/9 in BE. The patient was fine for 2 years, after which she developed progressive loss of vision in her RE for the next six months. Her vision was reduced to 4/60 in her RE, but her vision remained the same in her LE. On clinical evaluation, the patient showed dense posterior subcapsular cataracts in her RE. Dilatation of the pupil revealed focal anterior capsular fibrosis over the area of peripheral iridotomy [Figure 1] and [Figure 2]. She was diagnosed as having a post-YAG PI cataract. Hence, the patient was scheduled for explantation of the RIL followed by phacoemulsification of the opacified crystalline lens and implantation of a posterior chamber intraocular lens (PCIOL). Biometry was performed using IOL master 700 (Zeiss Inc.).
|Figure 1: Retroillumination of the eye showing good fundal glow with patent PI, the underlying focal anterior capsular, and a posterior subcapsular cataract|
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Surgical procedure [Video 1][Additional file 1]
A 3.2-mm self-sealing clear corneal incision was constructed in the superior cornea. A hydroxypropyl methylcellulose OVD was injected into the anterior chamber. With the help of a Sinsky hook, both haptics of the RIL were pulled out into the anterior chamber. Next, using curved forceps, the optic device was grabbed and pulled out of the eye. The tunnel was closed by a 10–0 nylon suture. Subsequently, phacoemulsification was performed by creating a new tunnel along the temporal quadrant. Standard phacoemulsification was performed through a 2.6-mm clear corneal tunnel using an infinity phaco machine (Alcon Inc.). A 5.5-mm capsulorhexis was performed, and complete removal of the cataractous lens was performed using a phaco probe with a Kelman tip and a coaxial I/A tip. A 3-piece intraocular lens was implanted into the capsule bag, and complete removal of the OVDs was ensured. A standard postoperative regimen of steroid antibiotic combination eye drops was administered for 2 weeks followed by a regimen of nonsteroidal anti-inflammatory eye drops for the next 4 weeks. Postoperative visual acuity improved to 6/9 and N8 and vision nearly returned to normal. Her refractive error was −0.75D spherical with −0.50 D cylinder at 90°. The patient had stable vision and no evidence of retinal complications for the next 24 months.
| Discussion|| |
Peripheral iridotomy using Nd:YAG lasers is a procedure that is performed without receiving immediate feedback or visualization of the outcome; thus, it is difficult to predict the amount of crater this technique creates with a single pulse of the laser. The release of pigment while applying the laser to the patient suggests that the laser achieves full-thickness iris penetration. The energy of each pulse varies depending upon the thickness and pigmentation of the iris. Indian eyes have thick and pigmented irises; hence, more energy is required to create a crater. Therefore, repeated pulses of lasers to create a patent iris opening accentuate the risk of deeper laser penetration, causing accidental damage to the anterior lens capsule. As the laser hits the anterior lens capsule, it creates a focal opening in the crystalline lens. Eventually, this opening exposes the internal secluded lens proteins to the aqueous humor. This exposure slowly denatures the lens proteins, causing focal opacification of the lens, which slowly denatures adjacent clear lens proteins, triggering complete opacification. Bobrow et al. observed 27.9% of cases developing cataract following laser peripheral iridotomy within 6 years of procedure. Therefore, it is essential to judiciously use laser energy while creating a crater, and once the crater is created, the amount of energy can be reduced as it is being delivered deeper into the iris.
| Conclusion|| |
Early cataract formation is an unwarranted complication of phakic IOL. YAG PI needs to be performed carefully by reducing the amount of energy administered once the crater is created to prevent deeper penetration of the energy and accidentally causing damage to the lens.
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.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2]