Introduction

A macular hole is a disorder found in the macula within the retina. The retina contains nerve cells that react to light and allow one to see. Within the macula, the nerve cells are close to each other, and when a jelly-like substance fills the eye, it pulls on the central macula and can cause a macular hole to form. It is important to address this issue as it can affect the vision for reading and driving.¹  

Understanding Macular Holes

Anatomy of the macula 

The macula is a part of the retina that processes what one sees directly in front of them. The macula is found in the centre of the retina and is a round, yellow spot. The macula is made up of photoreceptor cells. They contain rods, which are photoreceptor cells that process black and white light. They also contain cones which process colour, and both of them work together to give a clear and accurate vision of what one sees.

Initial causes of macular holes 

Age-related changes 

In most people, macular holes are likely to happen due to vitreous traction, and this often comes with age.²

Ocular trauma

Trauma is another major cause, especially in younger age groups. A traumatic macular hole may close spontaneously, but if it does not, it may require surgery. If it is not associated with any other condition, then it is called a primary macular hole.³

High myopia

People with high myopia can develop posterior bulging, causing posterior staphyloma. This then develops into a macular hole, which splits the retinal layers in the macula and causes an accumulation of intraretinal and subretinal fluid in the absence of a full-thickness macular hole.⁴

Recurrent macular holes

Definition and frequency

Recurrent macular holes tend to reopen after successful closure. Some of the risk factors for recurrent macular holes are high myopia, intraoperative retinal tears, cystoid macular edema and cataract surgery following macular hole surgery.⁵

Risk factors for recurrence 

Incomplete vitrectomy 

The primary surgery for a macular hole is the incomplete vitrectomy and this involves removing the vitreous gel and internal limiting membrane peeling. If the vitreous is still firmly attached to the retina when it is pulled away, then it can tear the retina and cause a macular hole again.⁶

Postoperative complications

Some complications that could occur after a post-operative surgery may include the reopening of a macular hole after a cataract surgery. Another cause may be the effect of the incomplete peeling of the internal limiting membrane (ILM) during the first surgery if no staining agent was used. Therefore, if the eye is not managed or treated properly after surgery, it can cause the macular holes to reopen.⁷

Diagnostic methods 

Optical Coherence Tomography (OCT)

It is a noninvasive, diagnostic technique that is used to accurately identify macular holes. It will assess pre-clinical changes leading to hole formation. The OCT forms a cross-sectional view that distinguishes the full thickness of macular holes, which allows for early diagnosis. On an OCT, a stage 1 hole looks like a cystic lesion in the inner layer of the retina; in stage 2, the macular hole has a full-thickness defect at the fovea. Stage 3 macular hole is evolved, and in stage 4, there is a complete posterior vitreous detachment. Therefore, the OCT allows for early diagnosis of the macular hole and can detect any changes in the retina.⁸

Visual acuity tests

Visual acuity tests are done to check how strong one’s eyesight is and this can help identify if there are any earlier symptoms for recurrent macular holes. Acuity is measured by conducting a variety of eye tests that determine how sharp or clear someone can see from 20 feet away. It tests their ability to read and see.⁹ There are two types of tests: one is the snellen test, and the other is the random E test.

Management strategies

Primary surgical intervention 

Pars plana vitrectomy with internal limiting membrane (ILM) peeling 

Currently, the standard of care for MH management is pars plana vitrectomy with internal limiting membrane peeling.¹⁰ When this primary surgery fails and the macular hole reopens. In order to manage this, an extension of the internal limiting membrane peel can be done. During this procedure, forceps are used to remove a circular area of the ILM measuring three to four disc diameters in size from around the hole. After this procedure, a full closure of the macular hole is confirmed.¹¹

Gas tamponade 

During the pars plana vitrectomy, a surgeon removes the vitreous gel from the eye and then peels the internal limiting membrane from the retina. Then, a gas bubble is injected into the vitreous cavity to tamponade the macular hole. This gas bubble pushes against the hole and allows it to close.¹²

Managing recurrent macular holes 

Repeat vitrectomy 

If the first surgery fails, then a second operation may be needed. A second vitrectomy is done to repair retinal detachments and further closure of the macular hole.¹³

Use of different tamponade agents (e.g., Silicone Oil)

Instead of a gas tamponade surgery, a different tamponade agent such as silicone oil can be used. An experiment was conducted where 33 patients received re-treatment by temporary tamponade of silicone oil. The closure rate was monitored and changed in visual acuity. At the end of the experiment, it was concluded that 30 out of the 33 patients had a full macular closure with the silicone oil tamponade. Therefore, higher results were shown with the use of silicone oil and an improvement of visual acuity was seen.¹⁴

Postoperative care 

Face-down positioning 

It is important to do face-down positioning as the tamponade needs to provide a mechanical flotation face at its apex against the macular hole, and this is only achieved when the patient is face down.¹⁵ The face-down positioning is only required for 3 to 7 days after surgery in order for the repair of the macular hole to heal.¹⁶

Regular follow-up and monitoring

After the surgery, it is important to refrain from strenuous activity and to keep the eye clean and dry. Some may be given eye drops to use. Furthermore, appropriate pain medication must be taken to avoid any pain or discomfort that one may have. Follow-up appointments and check-ups are important for monitoring healing and detecting any complications.¹⁶

Prognosis and Outcomes

Visual acuity outcomes are best for patients who have been symptomatic for less than six months before surgery. After the surgery, closure of the macular holes has resulted in an improvement in visual acuity. The chances of the macular hole reopening very much decrease, and the improvement in vision remains long-term in most patients.

Summary

In conclusion, recurrent macular holes occur when the first primary surgery fails and the macular hole reopens. This is resolved by performing extensive ILM peeling and gas tamponades. In order to ensure a safe recovery post-surgery, it is important that the patient follows the post-operative procedures and does regular follow-up checkups.