Hard nuclear fragments provide three-dimensional scaffold in cases with zonulopathy
The fragments can be positioned in the areas of zonulopathy in conjunction with capsular hooks, capsular tension ring or IOL.
Posterior capsule rupture with nucleus fragments inside the eye is a big challenge. Rohit Om Parkash, MBBS, MS, of India and colleagues have developed a new technique called nuclear scaffold to handle difficult cases. I invite them to explain this technique to us.
Amar Agarwal, MS, FRCS, FRCOphth
OSN Complications Consult Editor
Capsular support devices such as capsular hooks, capsular tension segments (CTS) and capsular tension rings (CTR) are used in zonulopathy to provide device-specific support to the capsular bag. The capsular-supporting devices are used as stand-alone support system or in conjunction with other devices. They assist in preserving zonular integrity, thereby providing stability to the capsular bag in cases with generalized zonulopathy or with varied degrees of zonular dehiscence. Despite providing substantial strength to the weak zonules and the capsular bag, these devices still have certain limitations and drawbacks. Surgeons face increased challenges in hard cataracts with zonulopathy.
What is nuclear scaffold?
Nuclear scaffold is an indigenous capsular bag support system to the compromised technique wherein the hard, nonemulsified nuclear fragments provide three-dimensional support to cases of generalized zonulopathy and in varied degrees of zonular dehiscence. Nuclear scaffold can function as an adjunct to the existing capsular support devices in cases with generalized zonulopathy or zonular dehiscence less than 180° (Figures 1 to 3).
How does nuclear scaffold function?
The hard, noncollapsible, voluminous nuclear mass, when placed in the area of zonular compromise, provides three-dimensional support:
a. Horizontal two-dimensional support: Equator of the nuclear fragment keeps the weak capsular fornix distended, thereby preventing any increase in area of zonular dehiscence.
b. Anteroposterior three-dimensional support: The bulk of the hard nuclear fragments scaffold the flaccid posterior capsule, preventing any iatrogenic trauma to it. These fragments keep the bag distended, preventing inadvertent collapse as a result of the aspirational fluidics.
When does nuclear scaffold work?
Hard nuclear fragments are used differently to provide intrinsic support to the capsular bag in different levels of zonulopathy.
a. Generalized zonulopathy: In cases with hard nucleus and generalized zonular weakness, inserting the CTR is difficult because of increased anteroposterior thickness of the nucleus. The capsular bag is anteroposteriorly supported and immobilized with capsular hooks. The nucleus is fragmented into different pieces and left in situ until all of the nuclear fragments have been divided and fully separated. The hard nuclear fragments act as a scaffold by giving additional support to the capsular bag all the time and help delay insertion of the CTR.
b. Zonular dehiscence: In cases with zonular dehiscence up to 180°, hard nuclear fragments are used as scaffold in conjunction with CTR/CTS, capsular hooks and/or a multipiece IOL to provide support to the compromised capsular bag. In zonular dehiscence less than 90°, nuclear fragments can be continuously placed in the small area of zonular dehiscence to provide three-dimensional support to the lax capsular bag. CTR provides horizontal and equatorial support to the capsular fornix while the multipiece IOL acts as a scaffold to the lax posterior capsule.
In 180° of zonular dehiscence, the capsular hooks are used to immobilize and provide anteroposterior support to the capsular bag. Hard nuclear fragments are placed in the area of dehiscence and repositioned continuously to provide additional three-dimensional support to the weak capsular bag. Hard nuclear fragments keep the bag distended in the area of zonular dehiscence and help in delaying the insertion of the CTR.
Hard nuclear fragments provide indigenous three-dimensional scaffold to the weak capsular bag in cases with zonulopathy. These fragments can be appropriately positioned in the areas of zonulopathy in conjunction with capsular hooks, CTR or IOL to allow uneventful completion of the procedure.
- For more information:
- Amar Agarwal, MS, FRCS, FRCOphth, is director of Dr. Agarwal’s Eye Hospital and Eye Research Centre. Agarwal is the author of several books published by SLACK Incorporated, publisher of Ocular Surgery News, including Phaco Nightmares: Conquering Cataract Catastrophes, Bimanual Phaco: Mastering the Phakonit/MICS Technique, Dry Eye: A Practical Guide to Ocular Surface Disorders and Stem Cell Surgery and Presbyopia: A Surgical Textbook. He can be reached at 19 Cathedral Road, Chennai 600 086, India; email: firstname.lastname@example.org; website: www.dragarwal.com.
- Rohit Om Parkash, MBBS, MS, can be reached at Dr. Om Parkash Eye Institute, 117-A, The Mall, Amritsar-143001, Punjab, India; email: email@example.com.
Disclosures: Agarwal and Parkash report no relevant financial disclosures.