_{Published: 26/11/2025, Reading time: 4 minutes}

The OS 4 Up brings new tools and refinements to cataract and vitreoretinal surgery. At ESCRS and Euretina 2025, experienced surgeons shared early impressions after hands-on testing in wet labs. 

Dynamic Infusion: Stable Chambers at Lower IOP

Dr. Florian Sutter’s insights (Switzerland) 

Dr. Sutter highlighted the benefit of operating at near-physiological IOPs. In his view, Dynamic Infusion keeps the anterior chamber stable—even when aspiration begins—without the need to constantly adjust bottle height. Especially for teaching environments, this stability helps reduce complications while preserving a soft, responsive eye. 

“We’re used to associating a soft eye with danger. Dynamic Infusion changes that.” (paraphrased) 

Oertli perspective 

Dynamic Infusion compensates for aspiration-induced pressure changes. This enables the surgeonu to keep IOP settings near the physiological level while maintaining stable intraocular conditions, even when operating with high flow and vacuum settings *. 

Phaco Assisted Cataract Surgery (PACS) 

Dr. Karl Boden’s observations (Germany) 

Dr. Boden explains that with PACS, lens fragments stick to the tip more effectively and melt down gently without turbulence. In Dr. Boden’s experience, PACS gives fine control over phaco power.  

“Feels like cruise control — precise and stable.” (paraphrased) 

Oertli perspective 

PACS (Phaco Assisted Cataract Surgery) is based on continuous modulation and contributes to precise and efficient work under stable chamber conditions.. With four phaco modulations, the OS 4 Up offers full flexibility in power control: Continuous, Pulse, Burst, and new PACS (Phaco Assisted Cataract Surgery).

With classic phaco modulation modes, the deflection of the phaco tip is controlled exclusively by the pedal position. PACS offers an additional advantage and regulates the movement of the phaco tip adaptively - comparable to cruise control *. 

Vitreoretinal Surgery: Access, Control, and Flow with Caliburn Trocar System and Continuous Flow Cutter 

Dr. Karsten Klabe’s summary (Germany) 

Dr. Klabe noted that the new Caliburn trocar system enters the sclera with less resistance. He prefers 27G for most cases now due to improved stiffness. He also emphasized that continuous flow and high cut rates reduce traction and help meet patient expectations for faster recovery. 

“Dr. Klabe noted that patients increasingly expect rapid visual recovery and a clear eye by Day 1.” (paraphrased) 

Oertli perspective 

The Continuous Flow Cutter delivers powerful performance thanks to the combination of 61% increased aspiration flow, up to 15’000 cpm and Oertli’s sophisticated fluidics system.  

Due to the high aspiration performance of the Continuous Flow Cutter, the Caliburn Trocar System provides 76 % more inflow with 23G and supports stable intraocular pressure conditions. Thanks to the bevelled trocar design, blade and cannula glide through the tissue in one seamless motion *. 

Conclusion

The new OS 4 Up offers several features. Here is a brief summary of some of them: 

• Dynamic Infusion: compensates for aspiration-induced pressure changes 
    – for IOP settings near the physiological level 
• PACS: Phaco assisted cataract surgery is based on continuous modulation and contributes to precise and efficient work under stable chamber conditions 
• Caliburn Trocar System: Smooth trocar placement with high cutting force 
• Continuous Flow Cutter: powerful performance with increased aspiration flow and up to 15’000 cpm 

From Oertli’s side, these solutions reflect our philosophy: 
Enjoy Surgery. Because great surgery starts with the right feeling.