Medical Policy

This document addresses the use of ocular pressure adjusting pump systems, such as the FSYX^™ Ocular Pressure Adjusting Pump (Balance Ophthalmics, Inc., Sioux Falls, SD), which apply negative periocular pressure through goggles worn during sleep to reduce intraocular pressure in individuals with glaucoma.

Note: For additional information regarding glaucoma, please see:

• DME.00050 Remote Devices for Intermittent Monitoring of Intraocular Pressure
• MED.00118 Continuous Monitoring of Intraocular Pressure

Note: For a high-level overview of this document, please see "Summary for Members and Families" below.

Medically Necessary:

Ocular pressure adjusting pump systems are considered medically necessary in individuals when all of the following criteria are met:

1. Diagnosis of open-angle glaucoma, including normal-tension glaucoma; and
2. Intended as adjunctive therapy for reducing intraocular pressure (IOP) during sleep; and
3. Age 18 years or older; and
4. At least one treated eye has a daytime intraocular pressure of 21 mm Hg or less; and
5. Current use, or previously trial of another intraocular pressure-lowering treatment (including prior laser or glaucoma surgery, if a candidate); and
6. Intraocular pressure reduction is needed to reach or maintain an individualized target intraocular pressure or reduce the risk of glaucomatous progression.

Continued use of an ocular pressure adjusting pump system is considered medically necessary when there is documentation of either of the following:

1. The condition for which the system was prescribed is still present; and
2. Use of the system has resulted in clinical benefit (for example, clinically meaningful decrease in intraocular pressure, no glaucomatous progression, etc.).

Investigational and Not Medically Necessary:

Ocular pressure adjusting pump systems are considered investigational and not medically necessary when the above criteria are not met.

This document describes clinical studies and expert recommendations and explains whether ocular pressure adjusting pumps are clinically appropriate. The following summary does not replace the medical necessity statement or other information in this document. The summary may not contain all the relevant criteria or information. This summary is not medical advice. Please check with your healthcare provider for any advice about your health.

Key Information

Ocular pressure adjusting pump devices involve use of goggles connected to a small pump. The goggles are worn during sleep. The pump creates gentle suction around the eyes to lower the pressure inside the eyes, known as intraocular pressure (IOP), while the device is being used.

What the Studies Show

Studies show that use of an ocular pressure adjusting pump can lower eye pressure in adults with open-angle glaucoma, an eye condition that could lead to blindness, including normal-tension glaucoma, who already have low eye pressure and still need more pressure reduction after other glaucoma treatment.

Is this clinically appropriate?

Lowering eye pressure is the main proven way to reduce the risk that glaucoma will get worse. This device is intended to be used with other glaucoma care and has not been established as an independent treatment for glaucoma.

(Return to Description/Scope)

Summary

The evidence supports the use of ocular pressure adjusting pump systems for adjunctive reduction of intraocular pressure (IOP) in a limited population of adults with open-angle glaucoma, including normal-tension glaucoma, who require additional pressure lowering despite current or prior treatment. This conclusion is based on the accepted role of intraocular pressure reduction as the principal modifiable treatment target in glaucoma and on clinical evidence showing that negative periocular pressure therapy produces clinically meaningful pressure reduction during device use. Because the available evidence does not establish the device as sole therapy or demonstrate long-term preservation of visual field or optic nerve structure, its use should be limited to adjunctive use for pressure reduction in a limited defined population.

Discussion

Clinical Importance of Intraocular Pressure Reduction

Glaucoma treatment is centered on reducing IOP to lower the risk of progressive optic nerve injury and visual-field loss. The American Academy of Ophthalmology (AAO) identifies IOP reduction as the principal modifiable treatment approach and describes an initial target reduction of approximately 20% to 30% below baseline, adjusted by disease severity and course (AAO, 2025). This framework is supported by major glaucoma trials. The Ocular Hypertension Treatment Study showed that ocular hypotensive medication reduced conversion to primary open-angle glaucoma (Kass, 2002). The Early Manifest Glaucoma Trial found less progression with IOP-lowering treatment and reported lower risk with each millimeter of mercury of IOP reduction (Heijl, 2002). The Collaborative Normal-Tension Glaucoma Study is particularly relevant to normal-tension glaucoma because it showed benefit from IOP reduction even when baseline pressures were not elevated (Collaborative Normal-Tension Glaucoma Study Group, 1998). The Advanced Glaucoma Intervention Study (AGIS) similarly associated lower achieved IOP with less visual-field deterioration (AGIS Investigators, 2000).

Unmet Need in Low-Pressure and Nocturnal Glaucoma

The published evidence and expert opinion identify an unmet need for individuals whose daytime IOP appears controlled but who continue to require additional pressure lowering. Nocturnal and supine IOP elevations may not be captured by routine office measurements, and conventional treatments may have variable nocturnal effects (Liu, 2004; Liu, 2016; Mosaed, 2005). A position statement from the American Glaucoma Society (AGS) and the American Society of Cataract and Refractive Surgery (ASCRS) identified improved IOP-lowering therapies, nocturnal IOP effects, 24-hour IOP monitoring, and adherence-reducing approaches as important unmet needs in primary open-angle glaucoma management (AGS, 2022). This supports the clinical rationale for a nonsurgical, nonpharmacologic adjunct that lowers IOP during sleep.

Evidence for Ocular Pressure Adjusting Pump IOP Lowering

Studies investigating the clinical impact of the ocular pressure adjusting pump system have consistently demonstrated IOP lowering during negative-pressure application. In the HERCULES trial, adults with normal-tension glaucoma had sustained IOP reduction through 52 weeks; 88.3% of study eyes met the in-clinic endpoint of at least 20% reduction, and 96.7% met the sleep-lab endpoint. Mean nocturnal IOP reduction was 8.0 mm Hg, or 39.1% (Ferguson, 2025). In the EXPLORER trial, 89.7% of treated eyes achieved at least 20% IOP reduction at Day 90 compared with 3.4% of control eyes (Samuelson, 2023). Additional continuous-wear, direct-manometry, and controlled negative-pressure studies support predictable IOP reduction while the device is worn (Ferguson, 2024; Peters, 2025; Swan, 2020).

Safety of Therapy

Reported safety findings from the available studies of the ocular pressure adjusting pump system have indicated acceptable results for the studied populations. Across the principal studies, no device-related serious adverse events were reported. Common adverse events included lid or periorbital edema and local periocular symptoms, which have generally been transient and have resolved with device removal or discontinuation (Ferguson, 2025; Samuelson, 2023).

Evidence Limits

The main limitation in the available body of evidence to date has been the absence of long-term trials proving preservation of visual fields, retinal nerve fiber layers, or optic nerve structures. However, IOP reduction has been an accepted modifiable target and intermediate measure for individuals with glaucoma. Because ocular pressure adjusting pump therapy reliably reduces IOP in the U.S. Food and Drug Administration (FDA)-cleared population, the evidence supports its use for that narrow indication (AAO, 2025; FDA, 2026; Ferguson, 2025). However, evidence remains insufficient outside adult open-angle glaucoma with IOP of 21 mm Hg or less and current or prior IOP-lowering treatment.

Glaucoma is a group of progressive optic neuropathies characterized by damage to the optic nerve and retinal ganglion cell axons that can result in irreversible visual field loss and blindness if untreated. Open-angle glaucoma is the most common form of glaucoma. Normal-tension glaucoma is a subtype of open-angle glaucoma in which optic nerve damage and visual field loss occur despite intraocular pressure (IOP) measurements within the statistically normal range.

IOP reduction is the primary modifiable treatment target in glaucoma. Current treatment options include topical IOP-lowering medications, laser trabeculoplasty or iridotomy, minimally invasive glaucoma surgery, and incisional glaucoma surgery. Some individuals continue to require additional pressure lowering despite current or prior treatment, including individuals with normal-tension glaucoma or low baseline IOP.

The FSYX Ocular Pressure Adjusting Pump system is a wearable medical device consisting of goggles connected to a programmable pressure-modulating pump. The device applies negative periocular pressure during sleep to temporarily lower IOP while negative pressure is being properly applied. The Multi-Pressure Dial (MPD) was a predecessor device used in earlier clinical studies of the same negative-pressure mechanism.

The Ocular Pressure Adjusting Pump system received U.S. Food and Drug Administration (FDA) De Novo classification (DEN230055) on June 27, 2024, establishing it as a Class II medical device under 21 Code of Federal Regulations (CFR) 886.5000 with product code QQJ. The FDA subsequently cleared the FSYX Ocular Pressure Adjusting Pump under 510(k) K252455 on April 30, 2026. The device is indicated for reduction of IOP during sleep in adult individuals with open-angle glaucoma and IOP of 21 mm Hg or less who are currently using or have undergone another IOP-lowering treatment. The effectiveness of the device to slow or halt glaucoma progression or to serve as sole IOP-lowering treatment has not been established (FDA, 2024; FDA, 2026).

Glaucoma: A group of progressive optic neuropathies characterized by damage to the optic nerve and retinal ganglion cell axons that can result in irreversible visual field loss and blindness if untreated.

Intraocular pressure (IOP): The fluid pressure inside the eye, measured in millimeters of mercury (mm Hg). Intraocular pressure is the principal modifiable treatment target in glaucoma.

Negative periocular pressure (NPP): A subatmospheric pressure environment created within a sealed goggle chamber surrounding the eye that lowers intraocular pressure by reducing atmospheric pressure in the periocular space.

Normal-tension glaucoma: A subtype of open-angle glaucoma in which progressive optic nerve damage and visual field loss occur despite intraocular pressure measurements within the statistically normal range.

Ocular pressure adjusting pump: A wearable medical device consisting of goggles connected to a programmable pressure-modulating pump that applies negative periocular pressure to lower intraocular pressure during device use.

Open-angle glaucoma: The most common form of glaucoma, in which the drainage angle between the iris and cornea remains open but aqueous humor outflow is reduced, contributing to optic nerve damage and visual field loss.

Target intraocular pressure: An individualized intraocular pressure goal selected by the treating clinician to reduce the risk of glaucomatous progression based on disease severity, baseline intraocular pressure, rate of progression, and other clinical factors.

Visual field: The total area in which objects can be seen in the peripheral vision while the eye is focused on a central point. Progressive visual field loss is a clinical indicator of glaucoma progression.

The following codes for treatments and procedures applicable to this document are included below for informational purposes. Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy. Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member.

When services may be Medically Necessary when criteria are met:

Associated Coding

When services may also be Medically Necessary for associated supplies when criteria are met for the device code listed above:

When services are Investigational and Not Medically Necessary:
For the procedure codes listed above when criteria are not met or for all other diagnoses not listed.

Peer Reviewed Publications:

1. AGIS Investigators. The Advanced Glaucoma Intervention Study (AGIS): 7. The relationship between control of intraocular pressure and visual field deterioration. Am J Ophthalmol. 2000; 130(4):429-440.
2. Collaborative Normal-Tension Glaucoma Study Group. The effectiveness of intraocular pressure reduction in the treatment of normal-tension glaucoma. Am J Ophthalmol. 1998; 126(4):498-505.
3. Ferguson TJ, Herndon LW, Terveen DC, et al. Application of negative pressure by the Ocular Pressure Adjusting Pump to provide a sustained reduction in IOP. Clin Ophthalmol. 2024; 18:3171-3178.
4. Ferguson TJ, Samuelson TW, Herndon L, et al. Negative pressure application by the Ocular Pressure Adjusting Pump to lower intraocular pressure in normal-tension glaucoma: HERCULES study. Am J Ophthalmol. 2025; 275:121-134.
5. Heijl A, Leske MC, Bengtsson B, et al. Reduction of intraocular pressure and glaucoma progression: results from the Early Manifest Glaucoma Trial. Arch Ophthalmol. 2002; 120(10):1268-1279.
6. Kass MA, Heuer DK, Higginbotham EJ, et al. The Ocular Hypertension Treatment Study: a randomized trial determines that topical ocular hypotensive medication delays or prevents the onset of primary open-angle glaucoma. Arch Ophthalmol. 2002; 120(6):701-713.
7. Liu JHK, Kripke DF, Weinreb RN. Comparison of the nocturnal effects of once-daily timolol and latanoprost on intraocular pressure. Am J Ophthalmol. 2004; 138(3):389-395.
8. Liu JHK, Slight JR, Vittitow JL, et al. Efficacy of latanoprostene bunod 0.024% compared with timolol 0.5% in lowering intraocular pressure over 24 hours. Am J Ophthalmol. 2016; 169:249-257.
9. Mosaed S, Liu JHK, Weinreb RN. Correlation between office and peak nocturnal intraocular pressures in healthy subjects and glaucoma patients. Am J Ophthalmol. 2005; 139(2):320-324.
10. Peters KS, Brambilla E, Ferguson TJ, et al. Manometric intraocular pressure reduction with negative pressure using Ocular Pressure Adjusting Pump goggles. Ophthalmol Glaucoma. 2025; 8(1):22-27.
11. Samuelson TW, Ferguson TJ, Brubaker JW, et al. Negative pressure application via a Multi-Pressure Dial to lower IOP in patients with suspected glaucoma or open angle glaucoma. J Glaucoma. 2023; 32(8):708-720.
12. Swan RJ, Ferguson TJ, Shah M, et al. Evaluation of the IOP-lowering effect of a Multi-Pressure Dial at different negative pressure settings. Transl Vis Sci Technol. 2020; 9(12):19.

Government Agency, Medical Society, and Other Authoritative Publications:

1. American Academy of Ophthalmology. Primary Open-Angle Glaucoma Preferred Practice Pattern. February 2026. For additional information visit the American Academy of Ophthalmology website: https://www.aao.org/education/preferred-practice-pattern/primary-open-angle-glaucoma-ppp. Accessed on August 14, 2026.
2. American Glaucoma Society; American Society of Cataract and Refractive Surgery. Unmet needs in the detection, diagnosis, monitoring, treatment, and understanding of primary open-angle glaucoma: a position statement of the American Glaucoma Society and the American Society of Cataract and Refractive Surgery. Ophthalmol Glaucoma. 2022; 5(5):465-467.
3. U.S. Food and Drug Administration. De Novo Classification Request for FSYX Ocular Pressure Adjusting Pump System. DEN230055. Rockville, MD: FDA. June 27, 2024. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/denovo.cfm?id=DEN230055. Accessed on August 14, 2026.
4. U.S. Food and Drug Administration. 510(k) Premarket Notification Database. FSYX Ocular Pressure Adjusting Pump. No. K252455. Rockville, MD: FDA. April 30, 2026. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm?ID=K252455. Accessed on August 14, 2026.

1. American Academy of Ophthalmology. Available at: https://www.aao.org. Accessed on August 14, 2026.
2. Glaucoma Research Foundation. Available at: https://glaucoma.org. Accessed on August 14, 2026.

FSYX (see Ocular Pressure Adjusting Pump)
Glaucoma, Normal-Tension
Glaucoma, Open-Angle
Intraocular Pressure
Multi-Pressure Dial
Negative Periocular Pressure
Ocular Pressure Adjusting Pump
OPAP (see Ocular Pressure Adjusting Pump)

The use of specific product names is illustrative only. It is not intended to be a recommendation of one product over another, and is not intended to represent a complete listing of all products available.

Federal and State law, as well as contract language, including definitions and specific contract provisions/exclusions, take precedence over Medical Policy and must be considered first in determining eligibility for coverage. The member’s contract benefits in effect on the date that services are rendered must be used. Medical Policy, which addresses medical efficacy, should be considered before utilizing medical opinion in adjudication. Medical technology is constantly evolving, and we reserve the right to review and update Medical Policy periodically.

No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, or otherwise, without permission from the health plan.

© CPT Only – American Medical Association