The term “malignant” may come off as alarming in the context of an eye issue. But in fact, malignant glaucoma is not a type of cancer. It’s a rare yet serious kind of secondary angle closure glaucoma that has to do with the fluids in the eye no longer moving in the natural course which is expected. Also known as aqueous misdirection syndrome, vitreous block, or ciliary block glaucoma.
This often develops post eye surgery especially in people that already have narrow drainage angles or angle closure glaucoma. This causes a fluid imbalance that in turn pushes intraocular structures out of place which may in some cases cause the front chamber of the eye to become abnormally small and also at times brings on a great increase in intra ocular pressure. As a rule this sustained pressure and structural changes will threaten vision and thus malignant glaucoma requires prompt examination and treatment by an ophthalmologist.
What Is Malignant Glaucoma?
In a healthy eye clear fluid which is the aqueous humour is produced constantly and usually flows forward before it leaves through the eye’s drainage system.
In the case of malignant glaucoma that is where the fluid movement is abnormal. Fluid may accumulate in the eye or be directed to the back of the eye instead of to the anterior chamber as it should. In which the pressure in the back of the eye is raised the lens and iris may be pushed forward.
As this process moves forward the anterior chamber which is the space between the iris and the cornea in this case becomes narrower in the center as well as at the periphery. The drainage angle may close up also which in turn will reduce outflow of fluid. Pressure in the eye is very much increased in most cases, though some patients do in fact get the disease with intraocular pressure that is in the normal range.
In that which does not follow typical pupillary block angle closure. In true aqueous misdirection the anterior chamber may still be shallow when we have a present functional peripheral iridotomy.
What Causes Malignant Glaucoma?
The exact cause of malignant glaucoma is a complex issue which is still under research. What we do know is that abnormal interaction between the ciliary body, lens, zonules, anterior vitreous and choroid plays a role in disrupting the normal forward flow of fluid in the eye.
It is most often seen post ophthalmic procedure. Glaucoma filtering surgery has in the past been related to the disease which we see particularly in eyes that have chronic angle closure. Also it may present after cataract surgery and other intra ocular procedures. At times Aqueous misdirection may present without a history of surgery.
Factors Associated With Higher Risk
| Risk factor | Why it may matter |
| Narrow or closed drainage angles | The front of the eye is already anatomically crowded |
| Shallow anterior chamber | Leaves less space when internal structures move forward |
| Shorter or smaller eye | Can increase anterior segment crowding |
| Previous angle-closure glaucoma | Frequently associated with aqueous misdirection |
| Previous malignant glaucoma | Increases concern about recurrence or involvement of the fellow eye |
| Certain glaucoma or cataract procedures | Changes in pressure inside the eye may trigger the condition in susceptible eyes |
Having at least one of these factors does not cause a person to get malignant glaucoma. In the large scale of things we don’t see it in most of our eye surgery patients which is the good news.
Malignant Glaucoma Symptoms
Malignant glaucoma symptoms present in a variable degree based on the rate of eye pressure change and the amount that the anterior chamber becomes closed.
Some report acute blurred or reduced vision. As intraocular pressure goes up we see eye discomfort and pain. Also may notice that vision becomes more short sighted temporarily which is a result of the lens-iris diaphragm moving forward. In the clinical setting we may note a very shallow anterior chamber which affects the center and the edges of the field.
Symptoms following recent eye surgery should never be ignored, particularly when they are new or worsening.
| Possible symptom or finding | What it may indicate |
| Sudden blurred vision | Change in eye pressure or position of internal eye structures |
| Eye pain or discomfort | May accompany increased intraocular pressure |
| Reduced vision | Can occur as the anterior chamber becomes shallow |
| Redness | May accompany postoperative inflammation or high pressure |
| Headache around the eye | Can occur with a rapid pressure rise |
| Very shallow anterior chamber | Important clinical sign identified during examination |
Severe eye pain or sudden loss of vision after surgery requires urgent medical assessment rather than waiting for a scheduled follow-up appointment.
How Is Malignant Glaucoma Diagnosed?
There is not a stand alone at home test for diagnosis of malignant glaucoma. An ophthalmologist will do an exam of the eye structure and intra ocular pressure and will also rule out other conditions which may cause a shallow anterior chamber.
The doctor generally examines the eye with a slit lamp and measures intraocular pressure. Gonioscopy can also help assess the drainage angle. One important finding is that both the central and peripheral anterior chambers are uniformly shallow, even when a functioning peripheral iridotomy is present.
Imaging is a useful tool. Ultrasound biomicroscopy may also look at the ciliary body and other front segment structures. Anterior segment OCT is great for measuring chamber depth and also the angle anatomy. In some cases of complex diagnosis B-scan ultrasound is used to rule out issues like a choroidal effusion or suprachoroidal hemorrhage.
Making that distinction is key in that we have postoperative eye conditions which may present in a similar way but in fact require very different treatments.
Is Malignant Glaucoma an Emergency?
Malignant glaucoma should be treated urgently.Repeated shift of the lens-iris structures and high pressure may cause eye damage and in some cases threaten sight.
In the event of recent cataract or glaucoma surgery or any other intraocular procedure, you should report to your ophthalmologist at once if you get sudden blurred vision, severe eye pain, progressive vision loss, or any other unusual symptoms.
Patients should not go off, stop or change glaucoma drops without first speaking to a medical professional as some of these medications may be inappropriate for aqueous misdirection.
Malignant Glaucoma Treatment
The aim of malignant glaucoma treatment is to restore normal fluid flow, enlarge the anterior chamber and manage intraocular pressure.
Treatment is based on the patient’s eye anatomy, past surgeries, pressure level and response to the first line of therapy.
Medical Treatment
Initial treatment may include use of prescription cycloplegic eye drops which in turn can move the lens and iris diaphragm back into place. Also doctors may put in medicines that reduce production of aqueous humour.
In some acute cases carbonic anhydrase inhibitors and hyperosmotic agents may be used. Also we may see to it that anti-inflammatory treatment is a part of the postoperative care when there is inflammation present. These treatments which require supervision by an ophthalmologist may also vary based on the patient’s eye.
Laser Treatment
In some cases when drugs do not fully restore normal fluid movement laser procedures may be performed in appropriate patients.
For example, Nd: YAG laser treatment is used in some pseudophakic or aphakic eyes to create a passageway through tissues which are blocking the flow of fluid. The exact technique used is very much determined by the presence of the patient’s natural lens and prior eye surgery.
Surgical Treatment
Persistent or at times recurring malignant glaucoma may require surgery.
Via vitrectomy which is a procedure that removes part of the vitreous body we are able to help create a passage which in turn allows for normal flow of fluid between the rear and front of the eye. In the clinical literature it is put forth that vitrectomy and procedures which disrupt the anterior hyaloid-zonular barrier are important options which play a role when medical and laser management fails.
Treatment of the eye is very much a case by case issue which is why we see value in early evaluation by a specialist ophthalmologist.
Can Malignant Glaucoma Come Back?
Recurrence is a possibility especially if the abnormal fluid passage has not been permanently fixed. If you have had aqueous misdirection in one eye report it to your ophthalmologist before undergoing any surgery in either eye.
This past medical history is what the surgeon uses to assess anatomical risk factors, which in turn allows for a careful procedural plan and arrangement of appropriate postoperative care.
When Should You See an Eye Doctor?
Seek urgent eye care if blurred vision, eye pain, or a major change in sight occurs after an eye operation. Those with narrow-angle or angle-closure glaucoma should be especially alert to unexpected symptoms after surgery.
Early detection does not always mean that malignant glaucoma is present. Many conditions produce similar symptoms, it is the in depth eye exam which will determine the base issue.
Conclusion
Malignant glaucoma also known as aqueous misdirection is a rare yet important ophthalmic emergency which we see to develop in what are anatomic prone eyes post operatively. Fluid flow is disturbed which in turn pushes the lens-iris diaphragm forward and to produce a shallow anterior chamber. We see raised intraocular pressure in many cases though normal pressure may also present.
Blurred vision and eye pain which may present post surgery has many causes thus self diagnosis is out of the question. A prompt exam in which an ophthalmologist is involved in is what will do the job of distinguishing between malignant glaucoma and other post op complications and at the same time he will02t hesitate to put forward the right medical, laser or surgical treatment.
If you see sudden vision changes, pain or atypical symptoms after an eye procedure, go to Vasan Eye Care or your nearby emergency eye care facility right away.
FAQs About Malignant Glaucoma
- Is malignant glaucoma cancer?
No. Despite the name, malignant glaucoma is unrelated to cancer. “Malignant” is a historical term referring to the condition’s difficult clinical behavior. Ophthalmologists now also call it aqueous misdirection syndrome, vitreous block, or fluid misdirection syndrome.
- How serious is malignant glaucoma?
It is a rare but serious eye issue. Within the eye there may be changes which produce a shallow anterior chamber and high eye pressure. Early diagnosis and proper treatment are key to protecting the eye and to reduce the risk of complications.
- Can malignant glaucoma occur after cataract surgery?
Yes. Although for many years it has been related to glaucoma surgery and angle closure eyes, aqueous misdirection also takes place after cataract surgery and other eye surgeries. It may present soon post op or in some cases many months after the procedure.
- Can malignant glaucoma happen when eye pressure is normal?
Yes. Eye pressure is high in most cases but in some which we term as malignant glaucoma can occasionally occur with normal intraocular pressure. Diagnosis in these cases is based on the full clinical picture which includes that of uniform anterior chamber shallowing and also we rule out other causes.
- Can malignant glaucoma be cured?
Many issues can be put into remission when we diagnose and treat them properly. We see response to medicine or laser in some, while others which are more persistent may require vitrectomy or some other surgical procedure to get back normal flow. Ongoing follow up is key because we see recurrences.