Posterior Capsular Opacification - Causes, Symptoms, and Treatments

Introduction

Cataract surgery is one of the most extensively practiced ophthalmic surgery, to enhance vision. Like every other surgery, cataract surgery also poses certain post-surgical issues and complications in the later phase. Posterior capsular opacification is the top leading trouble that is encountered post-surgically.

What Is Posterior Capsular Opacification?

Surgical complications are often inevitable, and every surgery holds the risk of future complications of varying degrees. Certain complications are reported immediately following the surgery while others develop years later. Surgical rectification of cataracts by substituting the lens frequently poses the risk of developing cloudiness in the lens capsule. This condition is medically known by the term posterior capsular opacification (PCO). Opaqueness is elicited in the capsule, especially at the back portion (posterior) and hence it is named posterior capsular opacification. It is extensively known by the synonym secondary cataract, however, PCO differs from cataract. In PCO, trouble is elicited in the capsule, while cataracts develop due to foggy lenses.

What Are Cataracts?

• Cataracts are the routinely observed eye disorder that significantly affects the quality of vision. These develop by the precipitation of certain proteins that make up the eye lens.

• The lens plays a pivotal role in facilitating vision, any form of opacity, cloudiness, and fading in the lens as such gets reflected in the vision.

• As a result, the person experiences remarkable visual disturbances like misty, foggy, and indistinguishable vision, thus greatly impacting the quality of one’s life.

• There are diverse root causes for the development of cataracts, however, aging is reported to be the prime silent culprit that over time results in notable changes in visual clarity.

• Surgical correction is the best treatment technique for cataracts. This cataractous lens is then surgically taken out without disturbing the lens capsule and replaced with a manmade lens (artificial lens) by following specific methods and procedures. Man-made lenses are technically known by the term intraocular lenses.

• The unharmed and perfectly retained lens capsule enhances the stability of the newly placed lens. Cataract surgeries work in this way to bring back normal vision to a visually compromised individual and bring about fruitful results for the patients.

What Leads to Posterior Capsular Opacification?

• Posterior capsular opacification develops as a part of the body's normal response following the surgery. With the advancement in technology, cataract surgery is designed in such a way that the capsule of the lens is retained and preserved without any damage while removing the lens.

• These capsules have specialized cells that are collectively known by the name LECs (Lens epithelial cells), which have the potential to develop into lens fibers. Even after cataract surgery, some of the LECs remain and resettle in the posterior capsular region by an abnormal migration process.

• The atypical piling-up of LECs in this particular area blocks and conceals the central axis of vision, which gets projected as a faded and blurry vision.

• Certain studies revealed that the use of certain external substances like (hyaluronic acids) triggers the process involved in the formation of cloudiness in the capsule, eventually leading to posterior capsular opacification.

What Are the Symptoms Associated With Posterior Capsular Opacification?

Posterior capsular opacification elicits symptoms that bear a close resemblance with that of cataracts. Some of the symptoms that are routinely encountered in PCO include the following:

• Diminishing Visual Acuity: The person elicits trouble in identifying the fine details of an object, like the shape. The sharpness of the vision also gets compromised.

• Cloudy Vision: There will be a remarkable lowering of image clarity. The individual often encounters dim and faded vision, posing challenges in the person’s day-to-day life.

• Diminished Color Perception: The person experiences trouble in recognizing and distinguishing colors. Colors often appear dim and dull.

• Glare: The individual frequently perceives a light source with an aura or radiance encircling the source of light. It often appears like a halo.

• Light Sensitivity: PCO occasionally elicits an abnormal sensitivity towards a light beam. It is technically known by the term photophobia, in which the person exhibits extreme difficulty in facing a light beam.

• Loss of Focus: The affected eye elicits challenges in focusing the objects, not only in the far vision but also in the near vision. Very rarely, the person may visualize two images of a single object, and the condition is medically known as double vision.

• Diminished Contrast Sensitivity: There will be challenges in appreciating the contrast and detecting variations of the shades in minute details.

How Is Posterior Capsular Opacification Diagnosed?

• An in-depth analysis of medical history and clinical diagnosis often aids in the diagnosis of posterior capsular opacification.

• A previous history of cataract surgery itself is self-explanatory and often guides the diagnosis on the right track. However, certain diagnostic tests and procedures are advised to confirm the diagnosis and to identify the intensity of PCO.

• Routinely advised investigatory procedure includes slit lamp examination. This test is carried out with the help of a special microscope. It reveals a clear picture of the retina and thereby, facilitates the detection of cloudiness in the capsule. A specific dilating agent is used to open up and broaden the pupil, which facilitates the examination.

What Are the Treatment Interventions Available for Posterior Capsular Opacification?

Posterior capsular opacification does not settle on its own. When PCO significantly impacts the vision, it necessitates treatment. The treatment strategy is more or less influenced by the age of the patients and the extent of visual compensation. Some of the extensively preferred treatment strategies include the following:

• Posterior Capsulotomy: In this technique, a specific beam of laser - Nd: YAG (Neodymium-doped Yttrium Aluminium Garnet) - is employed. Hence it is widely known by the name laser capsulotomy. The laser beam is used to create a tiny aperture (hole) in the opacified capsule, thereby facilitating the passage of light through the central axis. It is quite a simple technique and does not necessitate hospitalization. However, it may even pave the way for further complications.

• Surgical Capsulotomy: The core principle of this technique is quite similar to that of laser capsulotomy. But instead of a laser, the procedure is done surgically, in a more extensive manner. Hence this technique is not generally advised.

• Pars Plana Vitrectomy: This technique is advised for younger patients, particularly children in whom posterior capsulotomy cannot be carried out. In addition, membranectomy is also recommended for PCO correction in children.

Conclusion

Posterior capsular opacification is quite a familiar surgical complication that is reported globally. Just like cataracts, it influences the vision as well as the quality of life and demands medical attention. Laser treatment is an extensively advised and widely accepted treatment strategy with remarkable success rates.