Abstract
Visual floaters can significantly affect quality of vision. Although these opacities are visible on ophthalmoscopy, objectively measuring severity has been difficult. The standard approach has been to monitor individuals for complications rather than treating the floaters. With advances in surgical instrumentation and techniques, ophthalmologists have multiple options for treating visually significant floaters, most commonly pars plana vitrectomy and laser vitreolysis. This article aims to review the literature discussing methods for diagnosing and treating floaters.
Introduction
Visually significant vitreous opacities, commonly referred to as floaters, can frequently impact a patient’s quality of life. One survey sent to smartphone users reported that 76% of respondents reported floaters, 33% of whom had noticeable visual impairment.1 While this cannot be applied to the general population due to the selection bias of a smartphone survey selecting younger patients, it still shows the possibly high incidence of floaters.
The most common cause of floaters are primary vitreous opacities. These are caused by the degeneration of the vitreous gel structure leading to liquefaction of the vitreous body and aggregation of vitreous collagen fibers. This occurs with increasing age or earlier in patients with high myopia. Other common causes of visually significant floaters include posterior vitreous detachment (PVD), diabetic vitreopathy, and inflammation involving the posterior segment of the eye.2,3 Floaters may not impair visual acuity, but they can cause a decrease in contrast sensitivity and induce scattering of light. Both of these changes lead to subjective visual impairment.2 Patients often report difficulty with vision in bright light and trouble reading.4 The term myodesopsia – derived from Greek (myioides = flylike and opsis = vision) – describes the fragmented vision experienced by patients with floaters.2
Diagnosis
Despite the significant impact of vitreous opacities on vision, they are difficult to measure objectively. Floaters can be visible on fundoscopic exams, but their size or location does not always correlate with the severity of symptoms. Several imaging methods are used to document opacities.
Optical coherence tomography (OCT) can help clinicians identify the presence of vitreous opacities.3,5 However, it is better at identifying floaters closer to the retina than those in the central or anterior vitreous. Central vitreous opacities are typically the source of floater phenomena.3
Ophthalmic ultrasound, or B-scan, allows the visualization of the entire vitreous body. It can detect degeneration in the vitreous, often represented by a heterogenous appearance of the posterior segment. B-scan is also used to identify a PVD. Opacities can be more accurately identified using quantitative ultrasound. This technique involves layering multiple ultrasound frames into one image, like CT or MRI. Then, a computer algorithm determines specific regions of interest (ROI) and measures the energy, mean, and percentage of ROI occupied by opacities. Compared to other imaging modalities, this method correlates better with diminished contrast sensitivity and quality of life in these patients.6
Another imaging modality for floaters is infrared confocal scanning laser ophthalmoscopy (SLO). SLO has been shown to accurately grade the severity of opacities based on their size and proximity to the macula.7 SLO also provides a more dynamic view of anterior floaters not often detected by OCT. Additionally, a positive correlation exists between patients’ symptoms and the severity of opacities on SLO.8
Most commonly, these opacities can be documented with a wide-field color fundus photo (Optos plc., Marlborough, MA, USA), B-scan ultrasound, and near-infrared on OCT (Zeiss, Hebron, KY, USA) as shown in Figure 1.
Figure 1.
(A) B-scan ultrasound of PVD (arrow) with vitreous opacity, (B) color photograph of vitreous opacity, seen as hyperpigmented consolidation anterior to the retina (arrow), (C) fundus autofluorescence showing hypo-autofluorescent artifact (arrow) from vitreous opacity, (D) obscuration on OCT near-infrared reflectance from opacity (arrow), (E) OCT section of retina with shadow (arrow) of vitreous opacity.
Management of Vitreous Opacities
Many physicians take a conservative approach to managing vitreous opacities since they are sometimes difficult to appreciate objectively and visual acuity is often unchanged. This approach entails regular monitoring for retinal detachments (RDs) or breaks but no other intervention.9 Two forms of intervention are currently utilized. Pars plana vitrectomy (PPV) and Neodymium:yttrium-aluminum-garnet (nd:YAG) laser vitreolysis.
More recently, PPV for symptomatic floaters – colloquially termed “floaterectomy” – has become more accepted in the retina community.10 Arguments against PPV include the general risk of the surgery, unrealistic patient expectations and possible ridicule by the retina community.11
Pars Plana Vitrectomy Technique
PPV is a surgical procedure utilized to remove vitreous gel. Although the procedure has been performed for over forty years, the instrumentation has improved significantly over the past two decades. In this procedure, the light source, infusion cannula, and vitreous cutter are inserted through the pars plana portion of the eye. This approach prevents any injury to the retina and the natural lens. Currently, common instrumentation sizes used are 23, 25 or 27 gauge.
Small gauge vitrectomy instruments with high cut rates of vitreous may be less likely to cause intraoperative complications.12 The surgeon may or may not induce a posterior vitreous detachment (PVD). The induction of a PVD manually separates the vitreous gel from its attachment to the underlying retina resulting in more complete removal of vitreous.
Risks
The most common risk of PPV is the accelerated rate of cataract formation in phakic eyes. In multiple studies, approximately half of the otherwise healthy phakic eyes needed cataract extraction within five years following PPV.12 Limited or core vitrectomy without PVD induction preserves retrolental vitreous and may decrease the risk of early cataract formation or slow its progression. The risk of needing cataract extraction in these cases is approximately 20% within 12 months of the PPV.13
Postoperative RD is a less common complication of PPV. Intraoperative iatrogenic retinal tears can cause an RD necessitating further surgery. PVD induction may result in retinal tear formation, thereby increasing the risk of RD.12 There is also an increased risk in cases with larger gauge instruments or lower cut rates.12 Reports of retinal tears after elective PPV range from 3–16% of cases.14,15 The rate of RD is approximately 2%.16
Other infrequent postoperative complications associated with elective PPV are vitreous hemorrhage, macular edema, glaucoma, or endophthalmitis. These collectively occur in less than 5% of cases.
Benefits
The primary benefit of PPV for symptomatic floaters is a qualitative improvement in vision. As floaters do not dramatically impact visual acuity, most studies do not show a significant improvement in this outcome.17,18 However, patients report subjective improvement in vision and performance of daily activities, leading to an enhanced quality of life.19,20 Postoperatively, patients report high satisfaction.19,21 These outcomes are similar regardless of surgical technique.
Patients also experience objective improvements, especially of contrast sensitivity function.21,22 This can be measured with the Freiburg Acuity Contrast Test after patients adapt to a dark environment. This test requires patients to read dark grey letters on a lighter grey background, and the letters progressively get lighter in color. The amount of contrast sensitivity function can be measured with the Weber index, which calculates the difference in luminance between the letter and the background. These measurements can be used to compare pre-operative and post-operative function.
Quantitative ultrasound can confirm elective PPV’s beneficial outcomes.21 This can be done pre-operatively to detect the vitreous heterogeneity, but it should also be done post-operatively to ensure the removal of opacities. Vitreous echodensity typically diminishes after PPV, allowing confirmation of removal.
Nd:YAG Laser Vitreolysis
Laser vitreolysis is an alternative treatment for vitreous opacities. This method to treat vitreous opacities is cost-effective and minimally invasive compared to PPV, also decreasing the risk of postoperative infection.
YAG laser vitreolysis aims to disrupt a single large opacity into smaller fragments, reducing the size of the floater’s shadow on the retina. For multiple opacities, the laser is directed at the posterior hyaloid face, allowing the vitreous to collapse and reconfigure in the inferior pole.23 Typically, the ideal opacities to target are those in the central part of the vitreous cavity, away from the retina and retrolental region. The reported improvement of subjective visual function ranges from 50 to 70%.24,25 Most patients experience moderate symptom improvement and fewer report complete resolution.
Similar to PPV, the main complications of YAG laser vitreolysis are retinal tears and breaks, acceleration of cataract formation, and development of open-angle glaucoma.26–28 While there have been few reported cases of adverse events, most findings are from small-scale trials or case reports. More investigation is needed on the best technique and indication for YAG laser vitreolysis.
Conclusion
Visually significant floaters can pose a significant burden on patients. With advances in imaging and surgical instrumentation, there are now more definitive options to diagnose and treat these patients. Although these interventions are not without risks, the benefits may outweigh the risks for many patients, warranting thorough discussions on a case-by-case basis.
Footnotes
Nikki Gill, MD, is starting ophthalmology residency at the University of Missouri – Kansas City School of Medicine and Ajay Singh, MD, (pictured), is affiliated with the University of Kansas School of Medicine and the Kansas City VA Medical Center, Kansas City, Missouri.
Disclosure: No financial disclosures reported. Artificial intelligence was not used in the study, research, preparation, or writing of this manuscript.
References
- 1.Webb BF, Webb JR, Schroeder MC, North CS. Prevalence of vitreous floaters in a community sample of smartphone u.s. Int J Ophthalmol. 2013;6(3):402–405. doi: 10.3980/j.issn.2222-3959.2013.03.27. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Sebag J. Vitreous and Vision Degrading Myodesopsia. Prog Retin Eye Res. 2020;79:100847. doi: 10.1016/j.preteyeres.2020.100847. [DOI] [PubMed] [Google Scholar]
- 3.Milston R, Madigan MC, Sebag J. Vitreous floaters: Etiology, diagnostics, and management. Surv Ophthalmol. 2016;61(2):211–227. doi: 10.1016/j.survophthal.2015.11.008. [DOI] [PubMed] [Google Scholar]
- 4.Hahn U, Krummenauer F, Ludwig K. 23G pars plana vitrectomy for vitreal floaters: prospective assessment of subjective self-reported visual impairment and surgery-related risks during the course of treatment. Graefes Arch Clin Exp Ophthalmol. 2018;256(6):1089–1099. doi: 10.1007/s00417-018-3979-8. [DOI] [PubMed] [Google Scholar]
- 5.Ruminski D, Sebag J, Toledo RD, et al. Volumetric Optical Imaging and Quantitative Analysis of Age-Related Changes in Anterior Human Vitreous. Invest Ophthalmol Vis Sci. 2021;62(4):31. doi: 10.1167/iovs.62.4.31. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Mamou J, Wa CA, Yee KMP, et al. Ultrasound-based quantification of vitreous floaters correlates with contrast sensitivity and quality of life. Invest Ophthalmol Vis Sci. 2015;56(3):1611–1617. doi: 10.1167/iovs.14-15414. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7.Son G, Sohn J, Kong M. Acute symptomatic vitreous floaters assessed with ultra-wide field scanning laser ophthalmoscopy and spectral domain optical coherence tomography. Sci Rep. 2021;11(1):8930. doi: 10.1038/s41598-021-88371-9. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Garcia-Aguirre G, Henaine-Berra A, Salcedo-Villanueva G. Visualization and Grading of Vitreous Floaters Using Dynamic Ultra-Widefield Infrared Confocal Scanning Laser Ophthalmoscopy: A Pilot Study. J Clin Med. 2022;11(19):5502. doi: 10.3390/jcm11195502. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Broadhead GK, Hong T, Chang AA. To Treat or Not to Treat: Management Options for Symptomatic Vitreous Floaters. Asia-Pac J Ophthalmol Phila Pa. 2020;9(2):96–103. doi: 10.1097/APO.0000000000000276. [DOI] [PubMed] [Google Scholar]
- 10.Staff B. Retina Surgeons Share Their Treatment Preferences. [Accessed July 17, 2023]. Published November 10, 2022. https://www.reviewofophthalmology.com/article/retina-surgeons-share-their-treatment-preferences .
- 11.Cohen MN, Rahimy E, Ho AC, Garg SJ. Management of Symptomatic Floaters: Current Attitudes, Beliefs, and Practices Among Vitreoretinal Surgeons. Ophthalmic Surg Lasers Imaging Retina. 2015;46(8):859–865. doi: 10.3928/23258160-20150909-11. [DOI] [PubMed] [Google Scholar]
- 12.Zeydanli EO, Parolini B, Ozdek S, et al. Management of vitreous floaters: an international survey the European VitreoRetinal Society Floaters study report. Eye. 2020;34(5):825–834. doi: 10.1038/s41433-020-0825-0. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 13.Yee KMP, Tan S, Lesnik Oberstein SY, et al. Incidence of Cataract Surgery after Vitrectomy for Vitreous Opacities. Ophthalmol Retina. 2017;1(2):154–157. doi: 10.1016/j.oret.2016.11.012. [DOI] [PubMed] [Google Scholar]
- 14.Dysager DD, Koren SF, Grauslund J, Wied J, Subhi Y. Efficacy and Safety of Pars Plana Vitrectomy for Primary Symptomatic Floaters: A Systematic Review with Meta-Analyses. Ophthalmol Ther. 2022;11(6):2225–2242. doi: 10.1007/s40123-022-00578-9. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 15.Tan HS, Mura M, Oberstein SYL, Bijl HM. Safety of Vitrectomy for Floaters. Am J Ophthalmol. 2011;151(6):995–998. doi: 10.1016/j.ajo.2011.01.005. [DOI] [PubMed] [Google Scholar]
- 16.Mura M, Barca F, Dell’Omo R, Nasini F, Peiretti E. Iatrogenic retinal breaks in ultrahigh-speed 25-gauge vitrectomy: a prospective study of elective cases. Br J Ophthalmol. 2016;100(10):1383–1387. doi: 10.1136/bjophthalmol-2015-307654. [DOI] [PubMed] [Google Scholar]
- 17.Lin Z, Zhang R, Liang QH, et al. Surgical Outcomes of 27-Gauge Pars PLana Vitrectomy for Symptomatic Vitreous Floaters. J Ophthalmol. 2017;2017:5496298. doi: 10.1155/2017/5496298. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 18.Fink S, Kumar JB, Cunningham MA. Small-Gauge Pars Plana Vitrectomy for Visually Significant Vitreous Floaters. J Vitreoretin Dis. 2021;5(3):247–250. doi: 10.1177/2474126420961736. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 19.Morris RE. Vitreous Opacity Vitrectomy (VOV): Safest Possible Removal of “Floaters.”. Clin Ophthalmol Auckl NZ. 2022;16:1653–1663. doi: 10.2147/OPTH.S361557. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 20.Reference 20: Waseem TC. Pars Plana Vitrectomy for Symptomatic Vitreous Floaters: Another Look. Int J Ophthalmol Clin Res. 2021;8(1) doi: 10.23937/2378-346X/1410124. [DOI] [Google Scholar]
- 21.Sebag J, Yee KMP, Nguyen JH, Nguyen-Cuu J. Long-Term Safety and Efficacy of Limited Vitrectomy for Vision Degrading Vitreopathy Resulting from Vitreous Floaters. Ophthalmol Retina. 2018;2(9):881–887. doi: 10.1016/j.oret.2018.03.011. [DOI] [PubMed] [Google Scholar]
- 22.Sebag J, Yee KMP, Wa CA, Huang LC, Sadun AA. Vitrectomy for floaters: prospective efficacy analyses and retrospective safety profile. Retina Phila Pa. 2014;34(6):1062–1068. doi: 10.1097/IAE.0000000000000065. [DOI] [PubMed] [Google Scholar]
- 23.Delaney YM, Oyinloye A, Benjamin L. Nd:YAG vitreolysis and pars plana vitrectomy: surgical treatment for vitreous floaters. Eye. 2002;16(1):21–26. doi: 10.1038/sj.eye.6700026. [DOI] [PubMed] [Google Scholar]
- 24.Ludwig GD, Gemelli H, Nunes GM, Serracarbassa PD, Zanotele M. Efficacy and safety of Nd:YAG laser vitreolysis for symptomatic vitreous floaters: A randomized controlled trial. Eur J Ophthalmol. 2021;31(3):909–914. doi: 10.1177/1120672120968762. [DOI] [PubMed] [Google Scholar]
- 25.Nunes GM, Ludwig GD, Gemelli H, Zanotele M, Serracarbassa PD. Long-term evaluation of the efficacy and safety of Nd:YAG laser vitreolysis for symptomatic vitreous foaters. Arq Bras Oftalmol. doi: 10.5935/0004-2749.2021-0395. Published online September 23, 2022. S0004-27492022005010216. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 26.Hahn P, Schneider EW, Tabandeh H, Wong RW, Emerson GG. Reported Complications Following Laser Vitreolysis. JAMA Ophthalmol. 2017;135(9):973–976. doi: 10.1001/jamaophthalmol.2017.2477. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 27.Sun IT, Lee TH, Chen CH. Rapid Cataract Progression after Nd:YAG Vitreolysis for Vitreous Floaters: A Case Report and Literature Review. Case Rep Ophthalmol. 2017;8(2):321–325. doi: 10.1159/000477159. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 28.de Vries E, Faraj C, Gerbrandy F, Hulsman C. Secondary open-angle glaucoma following YAG-laser vitreolysis. BMJ Case Rep. 2022;15(4):e248937. doi: 10.1136/bcr-2022-248937. [DOI] [PMC free article] [PubMed] [Google Scholar]