An expert guide for ophthalmologists and surgical centres
Cataract surgery has evolved dramatically over the last few decades—transitioning from a procedure focused purely on lens removal to one that demands precision, tissue protection, and optimal postoperative outcomes. Among the many advancements that have shaped modern cataract surgery, Ophthalmic Viscosurgical Devices (OVDs) stand out as one of the most valuable innovations.
Today, no cataract procedure is complete without the strategic use of OVDs. These gel-like materials safeguard delicate ocular tissues, maintain anterior chamber stability, and contribute directly to surgical success. However, as technology improves and new formulations enter the market, the key question remains:
Are we using the right OVD, at the right time, in the right way?
This blog breaks down everything surgeons and hospitals need to know—types of OVDs, their benefits, selection guidelines, and practical usage tips that can elevate surgical outcomes.
What Are OVDs? A Quick Refresher
OVDs are transparent, gel-like substances used during cataract surgery to:
- Protect intraocular tissues
- Maintain chamber depth
- Coat and stabilize the cornea
- Create space for instrumentation
- Facilitate safe IOL implantation
Most OVDs contain one or more of the following substances:
- Sodium Hyaluronate
- Chondroitin Sulfate
- Hydroxypropyl Methylcellulose (HPMC)
- Healon / Viscoat-type formulations
Their unique rheological (flow) properties—viscosity, elasticity, cohesiveness—determine how they behave inside the eye and what role they play during surgery.
The Two Major Types of OVDs: Cohesive & Dispersive
Understanding the difference between cohesive and dispersive OVDs is essential for their correct use.
1. Cohesive OVDs – The Chamber Maintainers
Characteristics:
- High viscosity
- High surface tension
- Tend to stick to themselves (cohesion)
- Easy to remove in a single mass
Best for:
- Maintaining anterior chamber depth
- Creating space for capsulorhexis
- Implantation of IOLs
- Protecting tissues temporarily
Why surgeons love them:
Cohesive OVDs are extremely predictable. They occupy space efficiently and allow clean, quick removal—reducing the chance of postoperative pressure spikes.
Examples:
Healon GV, ProVisc, Z-Hyalin plus, etc.
2. Dispersive OVDs – The Tissue Protectors
Characteristics:
- Lower viscosity
- Tend to spread out
- Excellent for coating and protecting tissue
- More difficult to remove completely
Best for:
- Protecting corneal endothelium
- Situations with fluctuating chamber stability
- Compromised corneas
- Long surgeries
Why surgeons rely on them:
Dispersive OVDs stay in place and offer durable protection, especially during phacoemulsification where ultrasonic heat and turbulence can harm the endothelium.
Examples:
Viscoat, Ocucoat, etc.
The Rise of Soft-Shell & Ultimate-Shell Techniques
The evolution of cataract surgery demanded smarter ways to use OVDs—not just picking one type over another. This led to innovative techniques combining the strengths of both OVD types.
The Soft-Shell Technique
Developed by Dr. Steve Arshinoff, the soft-shell technique involves injecting:
- A dispersive OVD to coat the endothelium
- A cohesive OVD underneath it to create chamber space
What makes this technique effective:
- Superior endothelial protection
- Stable chamber during capsulorhexis
- Lower risk of corneal trauma
- Clear visibility during phaco
This technique remains one of the most widely adopted OVD strategies in challenging cataract cases.
The Ultimate Soft-Shell Technique (USST)
An advanced variation used especially during femto-assisted cataract surgeries and complex cases.
Benefits include:
- Better pre-phaco stabilization
- Reduced chance of capsular block
- Enhanced control during hydrodissection
Such modern techniques showcase how OVDs have evolved from “supporting agents” to “surgical enablers.”
Why OVDs Are Indispensable in Modern Cataract Surgery
Whether the surgeon is performing phacoemulsification, small-incision cataract surgery (SICS), or laser-assisted procedures, OVDs play multiple roles.
1. Protection of Corneal Endothelium
One of the most critical functions. Endothelial cells do not regenerate; hence OVDs provide:
- Thermal protection from phaco energy
- Cushioning against mechanical trauma
- Reduced turbulence impact
- Lower endothelial cell loss
Patients with Fuchs’ dystrophy or thin endothelium benefit greatly from dispersive OVDs.
2. Maintains Depth & Stability of the Anterior Chamber
A stable chamber equals safer surgery. OVDs:
- Prevent chamber collapse
- Improve visibility
- Help perform a controlled capsulorhexis
- Reduce risk of iris prolapse
- Cohesive OVDs are the preferred choice for consistent chamber maintenance.
3. Facilitate Capsulorhexis & Nucleus Manipulation
Capsulorhexis is one of the most delicate steps in cataract surgery. OVDs ensure:
- Improved visibility of the capsule
- Even pressure on tissues
- Reduced risk of radial tears
During nuclear rotation or hydrodissection, OVDs help create adequate space without traumatic pressure buildup.
4. Aid in Safe IOL Implantation
Lubrication and cushioning provided by OVDs make IOL insertion smooth and controlled.
Benefits:
- Reduced trauma
- Proper IOL unfolding
- Protection of posterior capsule
After implantation, cohesive OVDs allow easy aspiration.
5. Essential for Complex Cases
OVDs play a lifesaving role in:
- Shallow anterior chambers
- Weak zonules
- Pseudoexfoliation syndrome
- High-risk corneas
- Pediatric cataracts
- Dense cataracts requiring higher phaco energy
Their ability to create space and protect structures is unmatched.
Types of OVDs Based on Molecular Properties
Beyond the broad cohesive–dispersive division, OVDs differ based on their molecular formulations.
A. Viscoadaptive OVDs
These adapt their properties during surgery—behaving like cohesive OVDs in low turbulence and dispersive OVDs in high turbulence.
Benefit:
One product covers multiple surgical stages.
B. HPMC-Based OVDs
Cost-effective and ideal for:
- Supporting chamber stability
- IOL implantation
- Routine cataract cases
They are less protective during high-energy phaco but remain widely used in SICS and budget-sensitive environments.
C. HA-Based OVDs (Hyaluronic Acid)
These offer excellent elasticity and clarity and are used in:
- Premium cataract surgeries
- Complex cases requiring high stability
practical Tips for Surgeons: How to Use OVDs Effectively
Proper usage is just as important as selecting the right product.
1. Coat, Don’t Overfill
A common error is injecting too much OVD, which may increase intraocular pressure (IOP) post-operatively.
Use just enough to:
- Protect tissues
- Maintain chamber space
- Prevent collapse
2. Combine OVDs for Best Results
Modern cataract surgery increasingly uses combination strategies like:
- Soft-shell technique
- Tri-soft shell
- Ultimate soft shell
These methods offer optimal protection with minimal complications.
3. Remove OVD Thoroughly After IOL Implantation
Retained OVD is a leading cause of postoperative IOP spikes.
Recommendations:
Slow irrigation/aspiration
Thorough cleaning behind the IOL
Checking the angle for leftover dispersive OVD
4. Tailor OVD Choice to Cataract Density and Energy
Dense cataracts require stronger endothelial protection → dispersive OVDs.
Routine cataracts → cohesive or viscoadaptive OVDs work great.
5. Consider Patient Pathology
Examples:
- Fuchs’ dystrophy: Strong dispersive OVD
- Glaucoma: Avoid overfilling; choose easy-to-remove cohesive OVD
- Shallow chambers: Viscoadaptive or cohesive OVD
- Pseudoexfoliation: Combination OVD strategies
Patient-specific selection impacts long-term outcomes significantly.
Conclusion: OVDs Are the Unsung Heroes of Cataract Surgery
While surgical devices, phaco machines, and IOLs get much of the spotlight, OVDs quietly perform the critical job of protecting, stabilizing, and enabling safe surgery. Their proper use can significantly reduce complications, preserve corneal health, and improve the overall quality of vision.
Modern cataract surgery is no longer just about removing the cataract—it’s about achieving safe, predictable, and premium visual outcomes. And none of that is possible without choosing the right OVD and using it strategically.
As technology evolves, the next decade of OVD innovation will likely bring even safer formulations, smarter rheology, and more adaptive behaviours—further enhancing the precision and safety of ophthalmic surgery.