In 2012, Saheb and Ahmed introduced the 5 cardinal features of micro-invasive glaucoma surgery (MIGS). They highlighted an ab interno microincisional approach and extremely high safety profiles. This breakthrough has led to new, less invasive treatments for children with glaucoma. These surgeries aim to improve results and lower risks for young patients.
Ab-interno surgeries focus on the trabecular meshwork and Schlemm’s canal. They help to increase the flow of aqueous humour. This is different from traditional surgeries that make bigger cuts.
Key Takeaways
- Ab-interno surgeries for glaucoma in infants are minimally invasive treatment options that target the trabecular meshwork and Schlemm’s canal to enhance aqueous humour outflow.
- These procedures aim to improve outcomes and reduce complications in young patients with glaucoma, offering an alternative to traditional incisional surgeries.
- The 5 cardinal features of micro-invasive glaucoma surgery (MIGS), introduced in 2012, emphasise the ab interno microincisional approach and extremely high safety profiles.
- As of 2019, there were no randomised clinical trial data available on the safety and efficacy of glaucoma surgery in children, highlighting the need for further research in this specific population segment.
- Goniotomy success rates for childhood glaucoma range from approximately 50% to 85%, showcasing varying outcomes depending on the specific glaucoma type.
Introduction to Ab-interno Surgeries
Ab-interno surgeries are a type of glaucoma treatment. They are done through a small cut in the cornea, without touching the conjunctiva. These surgeries aim to improve the flow of fluid in the eye by working on the trabecular meshwork and Schlemm’s canal.
They are less invasive than older methods. This means patients can recover faster and face fewer complications. Plus, it keeps the conjunctiva intact for future treatments.
Definition and Purpose
Ab-interno surgeries, or MIGS, are designed to lower eye pressure in glaucoma patients. They try to improve fluid drainage by avoiding the trabecular meshwork. This helps reduce eye pressure.
Advantages over Traditional Approaches
Ab-interno surgeries have many benefits over older methods. They are quicker, with faster vision recovery. They also cause less inflammation and complications.
They also save the conjunctiva for future treatments. This is especially good for kids with glaucoma, where older surgeries might not work as well.
| Surgical Approach | Advantages | Disadvantages |
|---|---|---|
| Ab-interno Surgeries |
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| Traditional Glaucoma Surgeries |
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Ab-interno surgeries for glaucoma in infants are a less invasive option. They are very beneficial for kids, who often need many treatments over their lives.
“The introduction of ab-interno surgical techniques has revolutionised the management of glaucoma, particularly in the paediatric population, where the need for a less invasive approach is paramount.”
Goniotomy: The Original Ab-interno Procedure
Goniotomy is a key ab-interno glaucoma procedure from the 1940s. It involves a small corneal incision and a precise cut in the trabecular meshwork. This method has shown success rates from 50% to 85%. It works best for primary congenital glaucoma.
It’s often used in children with clear corneas for better angle view.
Surgical Technique
The goniotomy procedure starts with a small corneal incision. A special tool is then used to access and cut the trabecular meshwork. This method aims to improve aqueous humour outflow and lower IOP without harming the eye’s structure.
Success Rates and Indications
The success of goniotomy varies with the type of glaucoma. For primary congenital glaucoma, success rates are between 75% to 90%. In other childhood glaucomas, the success rate is about 70%.
Success depends on the glaucoma’s severity and the patient’s age at surgery.
Goniotomy is mainly for paediatric glaucoma, especially primary congenital glaucoma. It’s effective when the cornea is clear for good angle view. It’s a valuable treatment for young patients with the right conditions.
“Goniotomy has demonstrated success rates ranging from 50% to 85%, depending on the underlying glaucoma type, with better outcomes in primary congenital glaucoma.”
Gonio-Ablative Instruments
Gonio-ablative instruments like the Trabectome and Kahook Dual Blade have improved the goniotomy procedure. They aim to remove parts of the trabecular meshwork to reduce scarring and improve results. These tools are used through a small corneal incision, allowing for precise work under direct vision.
Trabectome
The Trabectome is a handheld, electrosurgical tool that removes parts of the trabecular meshwork. It’s designed to help aqueous outflow and lower eye pressure. Research shows it’s safe and effective, with results similar to traditional goniotomy.
Kahook Dual Blade
The Kahook Dual Blade is another tool for removing trabecular meshwork. Its design allows for precise tissue removal, potentially reducing scarring and improving long-term results. Early studies suggest it’s safe and effective in lowering eye pressure.
Both the Trabectome and Kahook Dual Blade offer alternatives to traditional goniotomy. They could lead to better results and safety. As they evolve, they might become key in treating glaucoma, especially in children where traditional methods are limited.
Gonioscopy-Assisted Transluminal Trabeculotomy (GATT)
Gonioscopy-Assisted Transluminal Trabeculotomy (GATT) is a new way to treat glaucoma in babies. It makes a bigger cut in the trabecular meshwork and Schlemm’s canal. This is better than the old way of treating glaucoma.
The GATT method uses a thin thread or microcatheter through a small eye cut. It goes into Schlemm’s canal and pulls out to make a full circle cut. This way, it treats the whole angle without needing a big cut in the eye’s outer layer.
| Surgical Approach | Trabecular Meshwork Treated | Incision Type |
|---|---|---|
| Goniotomy | Partial | Conjunctival |
| GATT | Circumferential (360 degrees) | Corneal |
The GATT method seems to work well, especially for treating the whole angle. Studies show it works for 60 to 90% of cases of glaucoma in kids.
Compared to older methods, GATT is safer and less invasive. It’s also cheaper, which makes it more appealing for treating glaucoma in young children.
Glaucoma in kids is common, affecting 6% to 42% of them. GATT could be a big help in treating this condition. It offers a safe and effective way to improve the lives of children with glaucoma.
Ab-interno Surgeries for Glaucoma in Infants
Managing childhood glaucoma, especially in infants, often means starting with surgery early. This helps control eye pressure and lets the eyes develop properly. Ab-interno surgeries are becoming popular because they are less invasive and can be done more than once without harming future surgeries. They also help keep the conjunctiva healthy, reducing risks from traditional surgeries.
Techniques like goniotomy and gonioscopy-assisted transluminal trabeculotomy (GATT) are becoming more common for treating ab-interno surgeries for glaucoma in infants. These surgeries are less invasive and offer benefits over older methods:
- They lower the chance of complications like scarring and damage to the conjunctiva, which can limit future surgeries
- They lead to quicker recovery times compared to more invasive surgeries
- They can be done again without greatly affecting future surgery options
Ab-interno surgeries also have advantages of ab-interno procedures in childhood glaucoma. They help control eye pressure better and reduce the need for eye drops. This is good for kids, who might find it hard to use eye drops and deal with their side effects.
“Ab-interno surgeries have revolutionised the way we manage glaucoma in infants and young children, providing a minimally invasive approach that can be repeated as needed without compromising future treatment options.”
As we learn more about treating glaucoma in kids, ab-interno surgeries are becoming key tools. They offer a promising alternative to older surgical methods for minimally invasive glaucoma surgery in paediatric patients.
Indications and Contraindications
Ab-interno glaucoma procedures are best for those with open-angle glaucoma and a clear cornea. They need a direct view of the anterior chamber angle. This makes them good for conditions like primary congenital glaucoma, where the angle is open and the cornea is clear.
Open Angle, Clear Cornea
People with open-angle glaucoma and a clear cornea are perfect for these surgeries. Techniques like goniotomy and GATT let surgeons directly work on the trabecular meshwork. This is where the main problem in open-angle glaucoma lies.
Angle Closure and Corneal Opacity
But, these surgeries aren’t right for angle closure glaucoma or significant corneal opacity. These issues make it hard to see what needs to be done. In such cases, other treatments might be better.
Choosing the right patients for ab-interno surgeries is very important. A detailed check-up, including gonioscopy and corneal tests, helps decide if these surgeries are right for each person.
“Identifying the right patients for ab-interno procedures is key to achieving optimal outcomes and minimising complications.”
Surgical Outcomes and Success Rates
Research shows good results from ab-interno procedures for kids with glaucoma. For primary congenital glaucoma, success rates can hit 85%. This is thanks to techniques like goniotomy and its variations.
In other childhood glaucomas, like those linked to cataracts or uveitis, success rates are between 50% and 60%. These methods are still being studied for long-term effects. Yet, they seem to work well in keeping eye pressure down and cutting down on more surgeries.
Primary Congenital Glaucoma
Children with primary congenital glaucoma have seen good results from surgery. A study covering 20 years found success rates of up to 85% with ab-interno procedures. The American Academy of Ophthalmology also backs the success of these surgeries for kids (Ophthalmology, 2014).
Other Childhood Glaucomas
For other childhood glaucomas, like those caused by cataracts or uveitis, success rates are between 50% and 60%. These methods are still being studied for long-term effects. Yet, they seem to work well in keeping eye pressure down and cutting down on more surgeries.
| Glaucoma Type | Success Rates of Ab-interno Surgeries |
|---|---|
| Primary Congenital Glaucoma | Up to 85% |
| Other Childhood Glaucomas (e.g., cataract, uveitis) | 50% – 60% |
“The surgical outcomes and success rates of ab-interno procedures in paediatric glaucoma management have been quite promising, with the potential to control intraocular pressure and reduce the need for additional interventions.”
Complications and Safety Profile
Ab-interno glaucoma procedures are often safer than traditional surgeries. They have a lower risk of serious adverse events. This is because they don’t damage as much tissue and make smaller cuts.
While some complications like cyclodialysis can happen, they are rare. This makes these surgeries a good choice for treating glaucoma in young children.
A study with 130 people with open-angle glaucoma showed good results. The intraocular pressure (IOP) dropped from 22.0 mmHg to 15.7 mmHg at 6 months. It then fell to 17.2 mmHg at 12 months after surgery.
Glaucoma medicine use also went down a lot. People used fewer medicines, from 2.8 before surgery to 1.1 at 12 months. At 24 months, it was 1.7 medicines per person.
These findings are very encouraging. They show that Ab-interno surgeries for glaucoma in infants can effectively lower eye pressure. They also reduce the need for glaucoma medicines, with significant results in many studies.
Comparative Effectiveness with Traditional Surgeries
The debate on choosing between ab-interno procedures and traditional surgeries for childhood glaucoma is ongoing. While there’s not much long-term data, studies suggest ab-interno methods can be good alternatives for some kids.
A recent study1 looked at different surgeries for primary congenital glaucoma (PCG). It found that IMCT, an ab-interno method, works better than traditional partial trabeculotomy. GATT, another ab-interno technique, also shows promise for certain glaucoma types in children.
Ab-interno surgeries might be better for kids because they save conjunctival tissue. This is good for kids who might need many surgeries. These surgeries also tend to have fewer complications than traditional surgeries.
“The ultimate choice of surgical approach should be tailored to the individual patient’s specific needs and glaucoma characteristics.”
Choosing the right surgery for kids with glaucoma depends on many things. These include the type and severity of the disease, the child’s age and health, and the surgeon’s skills. The aim is to find the best way to lower IOP, protect vision, and avoid complications.
As glaucoma surgery advances, more research is needed. We need to compare the long-term outcomes of ab-interno procedures and incisional glaucoma surgeries in children. This will help doctors and families make the best choices for treating childhood glaucoma.
Future Directions and Emerging Technologies
The field of ab-interno glaucoma surgery is growing fast. Newer MIGS devices and techniques are being developed. These include the iStent, CyPass, and Xen Gel Stent, aiming to improve aqueous humour outflow.
These advancements offer more options for treating paediatric glaucoma. As research and clinical experience grow, ab-interno procedures will become more crucial for young patients.
Newer MIGS Devices
Advances in MIGS devices have been impressive. They provide more targeted and customised solutions for glaucoma patients. Some notable emerging technologies include:
- The FDA-approved iTrack Advance, a second-generation device for ab-interno canaloplasty, showing progress in glaucoma management.
- Deviceless MIGS, which have shown effective short-term results in lowering intraocular pressure (IOP), with ongoing exploration into their long-term outcomes.
- The ELIOS trabeculotomy device uses an excimer laser, causing less tissue fibrosis and contributing to better IOP control.
- The Paul Glaucoma Implant, with a reduced lumen diameter, shows improved predictability in early IOP control for advanced glaucoma.
- The MINIject, a supraciliary MIGS implant, demonstrated promising IOP lowering over 24 months in clinical trials, potentially aiding severe, advanced glaucoma cases.
- The Travoprost intracameral implant, which showed noninferiority to topical timolol in IOP reduction, offering a sustained solution for glaucoma management.
- The PreserFlo MicroShunt, which produced a mean IOP reduction of 14.3 mm Hg in a study, highlighting its efficacy in subconjunctival MIGS procedures.
- The Calibreye System by Myra Vision, a novel device for subconjunctival MIGS, offering titrable outflow control for maximum IOP reduction and currently undergoing human trials.
These innovative MIGS devices, along with advancements in paediatric glaucoma management, promise a bright future for ab-interno glaucoma surgery.
Patient Selection and Decision-Making
Choosing the right patients for ab-interno glaucoma surgeries in kids is key. These methods work best for those with open-angle glaucoma and clear corneas. This is because they allow for a clear view of the angle.
Role in the Treatment Paradigm
The use of ab-interno surgeries in treating kids’ glaucoma is growing. They can be a good option or addition to traditional surgeries. This depends on the child’s specific needs and goals.
A study of 16 trials with 587 eyes in 446 kids with primary congenital glaucoma (PCG) found:
- Microcatheter-assisted 360-degree circumferential trabeculotomy might lower IOP and increase success rates. But, it could lead to more hyphema.
- 360-degree circumferential trabeculotomy seems to have better success rates than traditional trabeculotomy.
- There’s not much evidence on other surgeries for PCG, except for microcatheter-assisted 360-degree trabeculotomy.
This study shows how ab-interno surgeries are becoming more important in treating kids’ glaucoma. They might be better for certain cases than traditional methods.
| Surgical Procedure | Outcomes | Adverse Events |
|---|---|---|
| Microcatheter-assisted 360-degree circumferential trabeculotomy | Lower mean IOP and higher surgical success rates at 6 and 12 months | Higher incidence of hyphema |
| 360-degree circumferential trabeculotomy | Higher likelihood of surgical success compared to conventional trabeculotomy | Limited data available |
Choosing the right patients and using ab-interno surgeries wisely is vital. It helps in getting the best results for kids with glaucoma.
Conclusion
Ab-interno glaucoma surgeries are becoming key for treating kids with glaucoma. They are less invasive, leading to fewer complications and quicker healing. This method also keeps the conjunctiva ready for future treatments.
Techniques like goniotomy and gonio-ablative procedures have shown great results. They work well, especially for kids with primary congenital glaucoma.
Studies show these surgeries can control eye pressure well and reduce the need for medication. For example, a study found 70% of kids in the phaco-AIT group and 50% in the phaco-Trab group didn’t need eye drops after a year. But, the eye pressure change was slightly better for phaco-Trab.
As more research is done, these surgeries will likely become even more important for young patients. Ongoing studies, like the one comparing Trabectome to ab interno trabeculectomy, will help us understand their long-term benefits. The advancements in this area are promising for better care and results for kids with glaucoma.
FAQ
What are ab-interno surgeries for glaucoma in infants?
Ab-interno surgeries are new, less invasive treatments for kids with glaucoma. They work on the trabecular meshwork and Schlemm’s canal. This helps the eye drain fluid better, leading to quicker healing and fewer complications than old surgeries.
What are the advantages of ab-interno procedures over traditional glaucoma surgeries?
These new surgeries are better because they heal faster and have fewer side effects. They also keep the conjunctiva ready for future surgeries, unlike old methods.
What is goniotomy, and how does it work?
Goniotomy is a first ab-interno surgery for glaucoma. It makes a small cut in the cornea. Then, a special tool opens the trabecular meshwork for better drainage. It works well for some types of glaucoma, with success rates from 50% to 85%.
What are gonio-ablative instruments, and how do they differ from traditional goniotomy?
Gonio-ablative tools, like the Trabectome, remove parts of the trabecular meshwork. This is different from just cutting it, aiming to reduce scarring and improve results over time.
What is Gonioscopy-Assisted Transluminal Trabeculotomy (GATT), and how does it differ from other ab-interno procedures?
GATT is a surgery that makes a wider cut in the trabecular meshwork and Schlemm’s canal. It treats more of the angle than traditional goniotomy but doesn’t need a big incision in the conjunctiva.
What are the indications and contraindications for ab-interno glaucoma procedures in infants?
These surgeries are best for kids with open-angle glaucoma and clear corneas. They need a clear view of the angle to work. They’re not good for angle closure glaucoma or cloudy corneas because they can’t see well enough.
What are the success rates of ab-interno procedures in the management of paediatric glaucoma?
For primary congenital glaucoma, ab-interno surgeries like goniotomy can succeed up to 85% of the time. For other childhood glaucomas, success rates are between 50% and 60%.
How do the safety profiles of ab-interno procedures compare to traditional glaucoma surgeries?
Ab-interno surgeries are safer than old surgeries because they’re less invasive. They have fewer serious side effects. This is because they don’t damage the conjunctiva and make smaller cuts.
How do the long-term outcomes of ab-interno procedures compare to traditional glaucoma surgeries in children?
There’s not much research comparing long-term results. But, ab-interno surgeries seem to be good alternatives to old surgeries. They’re especially useful for kids who might need many surgeries over their lives.
What are the future directions and emerging technologies in the field of ab-interno glaucoma surgery?
Ab-interno glaucoma surgery is getting even better. New devices like the iStent and Xen Gel Stent are being developed. They aim to improve drainage and offer more options for treating kids with glaucoma.
