Introduction:
Glaucoma is a term referring to a group of eye disorders harming the optic nerve. The optic nerve transmits images from the eyes to the brain. Glaucoma is typically caused by increased intraocular pressure (IOP). Glaucoma can result in permanent vision impairment and blindness if left unaddressed.
So, undergoing an extensive examination for at least six months is essential. The standard treatment option for glaucoma includes eye drops to reduce the IOP. But, eye drops could not yield an effective and permanent outcome.
Therefore, micro-invasive glaucoma surgery (MIGS) procedures are structured to address the underlying problem in the drainage system and effectively manage the optic nerve damage and intraocular pressure. MIGS is gaining popularity among healthcare professionals and patients.
What Is Microinvasive Glaucoma Surgery?
Microinvasive glaucoma surgery (MIGS) is a minimally invasive surgery that employs microscopic implantable instruments and small incision surgery. This surgery option is safer to reduce intraocular pressure than standardized surgery. This is one of the newest and safest treatment options for glaucoma.
The MIGS procedures are categorized into three types based on how they achieve reduced or normal intraocular pressure.
-
Improving the natural drainage system of the eye and simply referred to as trabecular meshwork.
-
Redirecting or eliminating the excess ocular fluid from the eye.
-
Reducing the production of the ocular fluid inside the eye.
What Are the Common Microinvasive Glaucoma Surgical Procedures?
The following are the most common microinvasive glaucoma surgical procedures. Each of these procedures has a specific approach, indications, and contraindications.
-
Trabecular Meshwork: The trabecular meshwork bypass stents are the smallest device that healthcare providers implant into the trabecular meshwork. The trabecular meshwork is the drainage area or part of the eye. This particular procedure aids in creating a new pathway for aqueous drainage.
-
Minimally Invasive Trabeculectomy: Trabeculectomy is a minimally invasive procedure that works by creating a small opening in the sclera (the white color region of the eye) for the enhancement of fluid drainage. Trabeculectomy aims to decrease intraocular pressure by circumventing the trabecular meshwork.
-
Gonioscopy-Assisted Transluminal Trabeculectomy (GATT): This procedure involves acquiring and eliminating a portion of the trabecular meshwork by passing a microcatheter across the Schlemm’s canal )circular lymphatic-like small vessel of the eye). This procedure aids in improving the aqueous humor outflow.
-
Xen Gel Stent: Xen gel stent is a micro-invasive procedure where a small gelatin implant composed of porcine collage is implanted into the eye. This implant helps to develop a new track for decreasing intraocular pressure.
-
Canaloplasty: The canaloplasty approach incorporates accessing and clearing the natural drainage canal of the eye called the Sclemm’s canal to enhance fluid outflow. Here, a microcatheter inflates the Sclemm’s canal, followed by suture placement to keep the canal open.
Who Is the Right Candidate for Microinvasive Glaucoma Surgery?
Microinvaisve glaucoma surgery is indicated for reducing intraocular pressure in people with open-angle glaucoma and in cases where the individual suffers from both glaucoma and cataracts. MIGS procedures can be used as a single intervention or with other options, such as cataract surgery.
The following conditions can benefit from MIGS procedures.
-
Early-Stage Glaucoma: Early-stage glaucoma refers to the glaucoma condition that occurred before the age of 40. MIGS procedures are typically beneficial for individuals with early-stage glaucoma. This aims to slow down the progression of glaucoma while decreasing the need for invasive surgical interventions in the future.
-
Mild to Moderate Open-Angle Glaucoma: MIGS procedures are mostly considered for individuals with mild to moderate degrees of open-angle glaucoma in addition to laser therapy and medication. These micro-invasive procedures are recommended for patients requiring additional intraocular pressure reduction.
-
Cataracts and Glaucoma: The doctors perform MIGS procedures with cataract surgery to make it more advantageous for individuals with both cataracts and glaucoma.
-
Less Invasive Treatment: Microinvasive glaucoma surgical procedures are the most favorable treatment option for people preferring minimally invasive techniques with a rapid recovery period and minimal potential complications compared to standard glaucoma surgical interventions.
What Are the Contraindications of Microinvasive Glaucoma Surgery?
Microinvasive glaucoma surgery is a safe, effective, and well-tolerated surgical intervention. However, there are certain contraindications and situations where these procedures might not be recommended. The contraindication can vary based on the type of procedure and the individual’s conditions. The common contraindications and circumstances to consider for micro-invasive glaucoma surgery are as follows:
-
Advanced Glaucoma Stage: Microinvasive glaucoma surgery procedures might not be suitable for those with advanced forms of glaucoma. Here, standard and intense surgical interventions could help achieve adequate control over intraocular pressure (IOP).
-
Angle-Closure Glaucoma: Microinvasive glaucoma surgical procedures are generally not indicated for treating angle-closure glaucoma as this condition typically requires standard treatment to relieve the closure of the drainage angle and to achieve normal intraocular pressure.
-
Poor Surgical Candidates: The individuals are considered poor surgical candidates because of underlying medical conditions and previous ocular surgeries, which might increase the risk of complications associated with the surgical intervention. Micro-invasive glaucoma surgery might not be suitable for poor surgical candidates. Individual factors and health status are essential considerations for any surgery.
-
Severe Ocular Diseases: Individuals with severe ocular surface disorders like corneal abnormalities and severe dry eye might not be appropriate candidates for MIGS, as these conditions potentially impact the outcomes and interfere with the risk of complications.
-
Other Specific Contraindications: Every micro-invasive glaucoma surgical procedure has its own specific contraindications. So, implants and stents might not be appropriate for individuals with significant anatomical abnormalities or variations.
What Are the Complications of Microinvasive Glaucoma Surgery?
Microinvasive glaucoma surgery has minimal complications in a few cases. The potential complications of MIGS include corneal swelling, bleeding in the eye, temporary complications associated with intraocular pressure, and an increased risk of infections. Some cases have reported visual disturbances like double or blurred vision, but only temporarily.
Conclusion:
Microinvasive glaucoma surgery is generally performed as an outpatient surgical procedure and takes nearly ten to fifteen minutes. The recovery time is markedly short, but the recovery period might be extended when combined with other procedures like cataract surgery. This approach is considered a safe and well-tolerated procedure with relatively fewer complications. However, the doctors advise patients to attend follow-up visits to carefully assess the intraocular pressure changes and optic nerve damage.
