The Benefits of Smaller-Gauge, High-Speed, Dual-Blade Vitrectomy Cutters in Vitreous Opacity Surgery

Vitreous opacities, or “floaters,” are a condition for which patients commonly present to an ophthalmologist; of note, their clinical presentation can be quite variable and may significantly affect visual function. Some patients may experience the persistent effects of symptomatic floaters, while most patients typically do not experience significant visual impairment. They are commonly associated with the onset of posterior vitreous detachment (PVD), but when not associated with other conditions, vitreous floaters are generally considered to be benign in nature and do not lead to irreversible losses in visual acuity. Symptomatic floaters significant enough to require an evaluation are less common and oftentimes do not need surgical intervention.^1,2

A careful history and clinical examination can differentiate between the various pathologies attributable to floaters, including inflammatory causes such as uveitis, acute retinal tears, and even intraocular malignancies; pain, redness, or systemic symptoms should alert the clinician to a diagnosis other than vitreous floaters. Patients with symptomatic floaters typically have normal visual acuity, and as a result, findings that lead to the need for treatment can be challenging to identify and are sometimes difficult to quantify. More recently, there has been increasing acknowledgement of the problems associated with symptomatic floaters or myodesopsia. There has also been increasing interest by patients regarding the available treatment options with their associated risks.^1,2

There are no unanimously accepted guidelines on when patients should be considered for vitrectomy for vitreous floaters.³ Since vitreous floaters do not significantly impede common clinical measures of visual function such as visual acuity, contrast sensitivity measurement may be an important clinically relevant metric that can validate patient-reported visual impairment, and this has also correlated with improvement after intervention.^3,4,5 A recent presentation at the 2022 American Society of Retinal Specialists (ASRS) meeting by Shawn Kavoussi, MD (Texas Retina Center) described how infrared videography can supplement examination and other imaging modalities to potentially provide a more objective determination of the need for treatment of symptomatic floaters. Although infrared still photographs can enhance contrast of black opacities against a white fundus, these still photos may not identify intermittent foveal opacification. Additionally, OCT oftentimes cannot visualize the largest, most symptomatic opacities. Infrared videography appears to be a potentially important diagnostic tool to help identify symptomatic floaters that may benefit from treatment.⁶

For patients with persistent, significant symptoms, vitrectomy is a cost-effective, oftentimes successful treatment geared toward improving the symptoms of symptomatic floaters.² Several studies have evaluated the use of small-gauge vitrectomy used to treat symptomatic floaters. Sebag’s group evaluated the outcomes of 25-gauge vitrectomy for symptomatic floaters in patients with a mean age of 59 years and at least 24 months of visual symptoms due to floaters; no posterior vitreous detachments (PVDs) were induced intraoperatively, and the anterior vitreous was left intact. Normalization of contrast sensitivity function occurred in each case as early as 1 week after surgery and persisted at 9 months. No patient developed retinal breaks, retinal detachments, endophthalmitis, intraocular hemorrhage, or glaucoma at a mean follow-up time of 17.5 months.⁷ Lin’s group evaluated outcomes for 47 eyes of 47 fairly young patients with symptomatic floaters with a mean age of 34.7 years with symptomatic floaters for a median time of 18 months treated with 27-gauge pars plana vitrectomy. PVD was induced in only 22% of eyes without preexisting PVD, and anterior vitreous was preserved in all 42 postoperative phakic eyes. The median BCVA was the same as that preoperatively, and no lens injury, vitreous/retinal hemorrhage, or iatrogenic retinal breaks occurred intraoperatively.⁸ S.K. Steven Houston III, MD (Florida Retina Institute) recently presented a multicenter series of 825 eyes (mean age 69.9 ± 7.6 years) with symptomatic floaters experiencing symptoms for at least 6 months duration treated with small gauge pars plana vitrectomy at ASRS 2022 and noted that 92% of patients did not experience any surgical complications; the remaining 8% experienced new onset or progression of epiretinal membranes, cystoid macular edema and postoperative inflammation. Intraoperatively, the retinal detachment rate was less than 0.5% in pseudophakic patients with PVD and up to 2% for those without PVD. These patients were followed for 6 months postoperatively.⁹

What these studies have in common is that treating vitreous opacities using smaller-gauge vitrectomy appears to have a minimal occurrence of intraoperative complications, even in cases when PVD is induced. The comparable experimental flow capability of 27+ gauge dual-blade HYPERVIT (Alcon Vision LLC Fort Wort, TX) compared to the predecessor single-blade 25+ gauge Advanced ULTRAVIT^10,11 (Alcon Vision LLC Fort Worth, TX) (Figure 1) coupled with the decreased peak tractional forces in porcine vitreous^12,13 (Figure 2) may favorably affect both efficiency and safety.

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Figure 1. Porcine vitreous flowrate comparison of HYPERVIT 20,000 CPM versus Advanced ULTRAVIT 10,000 CPM probes.

Figure 2. Comparison of porcine vitreous peak traction force: HYPERVIT versus Advanced ULTRAVIT at various duty cycles.

I have recently begun using the 27+ gauge HYPERVIT in my vitreous opacity as well as other vitreoretinal cases, and it has provided me additional confidence with its predictability and controllability. The 27-gauge Vitrectomy System from Alcon allows creation of scleral incisions that self-seal without the need for a more tangential entry angle for trocar placement. The HYPERVIT cutter allows the surgeon to safely and efficiently remove vitreous gel in a manner similar to the 25-gauge Vitrectomy System. The 20,000 cut rate of the HYPERVIT allows for rapid vitreous removal without compromising stability, resulting in minimal retinal movement.¹⁴ The stiffness of the 27+ gauge HYPERVIT cutter will remind the surgeon of the stiffness found with the 25-gauge cutter. The ability to shave the peripheral vitreous gel safely despite the close proximity of the beveled cutter tip to the retinal surface¹⁵ is truly a welcome benefit in my cases.

The 27-gauge HYPERVIT has become a formidable tool in my armamentarium for many of the retinal cases I perform, but its efficiency and safety profile when applied to patients with floaters experiencing persistent visual disturbances, but with nearly normal visual acuity, gives me confidence that I will provide them an excellent surgical outcome with the improved vision that they expect.

1. Ryan EH. Current treatment strategies for symptomatic vitreous opacities. Curr Opin Ophthalmol. 2021 May 1;32(3):198-202.

2. Broadhead GK, Hong T, Chang AA. To Treat or Not to Treat: Management Options for Symptomatic Vitreous Floaters. Asia Pac J Ophthalmol (Phila). 2020 Mar-Apr;9(2):96-103.

3. Castilla-Marti M, van den Berg TJ, de Smet MD. Effect of vitreous opacities on straylight measurements. Retina. 2015 Jun;35(6):1240-6.

4. Garcia GA, Khoshnevis M, Yee KMP, Nguyen-Cuu J, Nguyen JH, Sebag J. Degradation of Contrast Sensitivity Function Following Posterior Vitreous Detachment. Am J Ophthalmol. 2016 Dec;172:7-12.

5. Garcia GA, Khoshnevis M, Yee KMP, Nguyen JH, Nguyen-Cuu J, Sadun AA, Sebag J. The effects of aging vitreous on contrast sensitivity function. Graefes Arch Clin Exp Ophthalmol. 2018 May;256(5):919-925.

6. Kavoussi SC. Infrared Video for the demonstration and quantification of macula-involving symptomatic vitreous opacities. American Society of Retinal Specialists Meeting. July 14, 2022; New York, NY; USA.

7. Sebag J, Yee KM, Wa CA, Huang LC, Sadun AA. Vitrectomy for floaters: prospective efficacy analyses and retrospective safety profile. Retina. 2014 Jun;34(6):1062-8.

8. Lin Z, Zhang R, Liang QH, Lin K, Xiao YS, Moonasar N, Wu RH. Surgical Outcomes of 27-Gauge Pars Plana Vitrectomy for Symptomatic Vitreous Floaters. J Ophthalmol. 2017;2017:5496298.

9. Houston SSK. Pars plana vitrectomy for symptomatic vitreous opacities: Large multicenter case series. American Society of Retinal Specialists Meeting. July 14, 2022; New York, NY; USA.

10. Zhu Y, Abulon DJK. Performance Evaluation of 25-Gauge 20,000 cpm Vitrectomy Probes: Vitreous Flow Rates. Poster #5301 presented at EVER 2019; October 17-19, 2019; Nice, France.

11. Abulon DJK, Zhu Y. Vitreous Flow Rates of 27-Gauge Dual-Cutting 20,000 cpm Vitrectomy Probes. Poster #5307 presented at EVER 2019; October 17-19, 2019; Nice, France.

12. Alcon Data on File, 2018.

13. Alcon Data on File, 2018.

14. Irannejad AM, Abulon DJK. How a beveled tip impacts flow around the probe. Poster presented at Euretina 2019. September 5-8, 2019; Paris, France.

15. Alcon Data on File, 2017.

Courtney Crawford, MD, FACS is a paid consultant for Alcon.

© 2022 Alcon Inc. 8/22 US-HV-2200002

Advanced ULTRAVIT at various duty cycles. 

MIVS IMPORTANT PRODUCT INFORMATION 

Caution: Federal law restricts this device to sale by, or on the order of, a physician. 

Indications for Use: The CONSTELLATION® Vision System is an ophthalmic microsurgical system that is indicated for both anterior segment (i.e., phacoemulsification and removal of cataracts) and posterior segment (i.e., vitreoretinal) ophthalmic surgery. 

The ULTRAVIT® Vitrectomy Probe is indicated for vitreous cutting and aspiration, membrane cutting and aspiration, dissection of tissue and lens removal. The valved entry system is indicated for scleral incision, canulae for posterior instrument access and venting of valved cannulae. The infusion cannula is indicated for posterior segment infusion of liquid or gas. 

Warnings and Precautions: 

The infusion cannula is contraindicated for use of oil infusion. 

Attach only Alcon supplied products to console and cassette luer fittings. Improper usage or assembly could result in a potentially hazardous condition for the patient. Mismatch of surgical components and use of settings not specifically adjusted for a particular combination of surgical components may affect system performance and create a patient hazard. Do not connect surgical components to the patient’s intravenous connections. 

Each surgical equipment/component combination may require specific surgical setting adjustments. Ensure that appropriate system settings are used with each product combination. Prior to initial use, contact your Alcon sales representative for in-service information. 

Care should be taken when inserting sharp instruments through the valve of the Valved Trocar Cannula. Cutting instrument such as vitreous cutters should not be actuated during insertion or removal to avoid cutting the valve membrane. Use the Valved Cannula Vent to vent fluids or gases as needed during injection of viscous oils or heavy liquids. 

Visually confirm that adequate air and liquid infusion flow occurs prior to attachment of infusion cannula to the eye. 

Ensure proper placement of trocar cannulas to prevent sub-retinal infusion. 

Leaking sclerotomies may lead to post operative hypotony. 

Vitreous traction has been known to create retinal tears and retinal detachments. 

Minimize light intensity and duration of exposure to the retina to reduce the risk of retinal photic injury. 

ATTENTION: Please refer to the CONSTELLATION® Vision System Operators Manual for a complete listing of indications, warnings and precautions.