053 Form

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Medical Policy Ophthalmologic Techniques That Evaluate the Posterior Segment for Glaucoma
Table of Contents • Policy: Commercial • Description
• References • Policy: Medicare • Policy History
• Coding Information • Authorization Information • Information Pertaining to All Policies • Endnotes Policy Number: 053

BCBSA Reference Number: 9.03.06 (For Plan internal use only) Related Policies
Optical Coherence Tomography of the Anterior Eye Segment, #084 Policy1 Commercial Members: Managed Care (HMO and POS), PPO, and Indemnity

Retinal nerve fiber analysis (RNFA), also known as scanning computerized ophthalmic diagnostic imaging (SCODI), which includes two methods of SCODI (confocal scanning laser ophthalmoscopy and scanning laser polarimetry), in addition to posterior segment optical coherence tomography, may be MEDICALLY NECESSARY for the following indications:

• To diagnose early glaucoma and monitor glaucoma treatment, • To differentiate causes of other optic nerve disorders when a diagnosis is in doubt, • To diagnose and manage the patient's condition when visual field results are insufficient; or when reliable visual field testing cannot be performed, due to visual, physical, mental, or age constraints, • To differentiate when a discrepancy exists between the clinical appearance of the optic nerve and the visual fields, • To detect further loss of optic nerve or retinal nerve fiber layer changes in the presence of advanced optic nerve damage and advanced visual field loss, • To diagnose and manage medically and surgically retinal and neuro-ophthalmic diseases which involve changes in the optic nerve, subretinal and intraretinal changes, vitreo-retinal relationships, and changes in the nerve fiber layer, and • To follow glaucoma suspects.

Retinal nerve fiber analysis and SCODI (also known as confocal scanning laser polarimetry and scanning laser polarimetry), including optical coherence tomography, for conditions not listed above (including, but not limited to, screening) is INVESTIGATIONAL.

The measurement of ocular blood flow, pulsatile ocular blood flow, or blood flow velocity in the diagnosis and follow-up of individuals with glaucoma is INVESTIGATIONAL.

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Prior Authorization Information
Inpatient • For services described in this policy, precertification/preauthorization IS REQUIRED for all products if the procedure is performed inpatient.
Outpatient • For services described in this policy, see below for products where prior authorization might be required if the procedure is performed outpatient.

Outpatient Commercial Managed Care (HMO and POS) Prior authorization is not required. Commercial PPO and Indemnity Prior authorization is not required. CPT Codes / HCPCS Codes / ICD Codes Inclusion or exclusion of a code does not constitute or imply member coverage or provider reimbursement. Please refer to the member’s contract benefits in effect at the time of service to determine coverage or non-coverage as it applies to an individual member.
Providers should report all services using the most up-to-date industry-standard procedure, revenue, and diagnosis codes, including modifiers where applicable.

The following codes are included below for informational purposes only; this is not an all-inclusive list.

The above medical necessity criteria MUST be met for the following codes to be covered for Commercial Members: Managed Care (HMO and POS), PPO, Indemnity, Medicare HMO Blue and Medicare PPO Blue: CPT Codes CPT codes: Code Description 92133 Computerized ophthalmic diagnostic imaging (eg, optical coherence tomography [OCT]), posterior segment, with interpretation and report, unilateral or bilateral; optic nerve 92134 Scanning computerized ophthalmic diagnostic imaging, posterior segment, with interpretation and report, unilateral or bilateral; retina 92137 Computerized ophthalmic diagnostic imaging (eg, optical coherence tomography [OCT]), posterior segment, with interpretation and report, unilateral or bilateral; retina, including OCT angiography

The following CPT code is considered investigational for Commercial Members: Managed Care (HMO and POS), PPO, Indemnity, Medicare HMO Blue and Medicare PPO Blue:

CPT Codes CPT codes: Code Description 0198T Measurement of ocular blood flow by repetitive intraocular pressure sampling, with interpretation and report

Description Diagnosis and Management A comprehensive ophthalmologic exam is required for the diagnosis of glaucoma, but no single test is adequate to establish diagnosis. A comprehensive ophthalmologic examination includes assessment of the optic nerve, evaluation of visual fields, and measurement of ocular pressure. The presence of characteristic changes in the optic nerve or abnormalities in visual field, together with increased intraocular pressure (IOP), is sufficient for a definitive diagnosis. However, some patients will show ophthalmologic evidence of glaucoma with normal IOPs. These cases of normal-tension glaucoma are considered to be a type of

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primary open-angle glaucoma. Angle-closure glaucoma is another type of glaucoma associated with an increase in IOP. The increased IOP in angle-closure glaucoma arises from a reduction in aqueous outflow from the eye due to a closed angle in the anterior chamber. Diagnosis of angle-closure glaucoma is detailed in policy #084.

Conventional management of patients with glaucoma principally involves drug therapy to control elevated IOPs, and serial evaluation of the optic nerve, to follow disease progression. Standard methods of evaluation include careful direct examination of the optic nerve using ophthalmoscopy or stereo photography or evaluation of visual fields. There is interest in developing more objective, reproducible techniques both to document optic nerve damage and to detect early changes in the optic nerve and retinal nerve fiber layer before the development of permanent visual field deficits. Specifically, evaluating changes in retinal nerve fiber layer thickness has been investigated as a technique to diagnose and monitor glaucoma. However, IOP reduction is not effective in decreasing disease progression in a significant number of patients, and in patients with normal-tension glaucoma, there is never an increase in IOP. It has been proposed that vascular dysregulation is a significant cause of damage to the retinal nerve fiber layer, and there is interest in measuring ocular blood flow as both a diagnostic and a management tool for glaucoma. Changes in blood flow to the retina and choroid may be particularly relevant for diagnosis and treatment of normal-tension glaucoma. A variety of techniques have been developed, as described below. (Note: This evidence review only addresses techniques related to the evaluation of the optic nerve, retinal nerve fiber layer, or blood flow to the retina and choroid in patients with glaucoma.)

Techniques to Evaluate the Optic Nerve and Retinal Nerve Fiber Layer

Confocal Scanning Laser Ophthalmoscopy Confocal scanning laser ophthalmoscopy is an image acquisition technique intended to improve the quality of the eye examination compared with standard ophthalmologic examination. A laser is scanned across the retina along with a detector system. Only a single spot on the retina is illuminated at any time, resulting in a high-contrast image of great reproducibility that can be used to estimate retinal nerve fiber layer thickness. In addition, this technique does not require maximal mydriasis, which may be problematic in patients with glaucoma. The Heidelberg Retinal Tomograph is a commonly used technology.

Scanning Laser Polarimetry The retinal nerve fiber layer is birefringent (ie, biorefractive), meaning that it causes a change in the state of polarization of a laser beam as it passes. A 780-nm diode laser is used to illuminate the optic nerve. The polarization state of the light emerging from the eye is then evaluated and correlated with retinal nerve fiber layer thickness. Unlike confocal scanning laser ophthalmoscopy, scanning laser polarimetry can directly measure the thickness of the retinal nerve fiber layer. GDx is a common scanning laser polarimetry device. GDx contains a normative database and statistical software package that compares scan results with age- matched normal subjects of the same ethnic origin. The advantages of this system are that images can be obtained without pupil dilation and evaluation can be completed in 10 minutes. Current instruments have added enhanced and variable corneal compensation technology to account for corneal polarization.

Optical Coherence Tomography Optical coherence tomography uses near-infrared light to provide direct cross-sectional measurement of the retinal nerve fiber layer. The principles employed are similar to those used in B-mode ultrasound except light, not sound, is used to produce the 2-dimensional images. The light source can be directed into the eye through a conventional slit-lamp biomicroscope and focused onto the retina through a typical 78-diopter lens. This system requires dilation of the patient’s pupil. Optical coherence tomography analysis software is being developed to include optic nerve head parameters with spectral domain optical coherence tomography, analysis of macular parameters, and hemodynamic parameters with Doppler optical coherence tomography and optical coherence tomography angiography.

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Pulsatile Ocular Blood Flow The pulsatile variation in ocular pressure results from the flow of blood into the eye during cardiac systole. Pulsatile ocular blood flow can thus be detected by the continuous monitoring of IOP. The detected pressure pulse can then be converted into a volume measurement using the known relation between ocular pressure and ocular volume. Pulsatile blood flow is primarily determined by the choroidal vessels, particularly relevant to patients with glaucoma because the optic nerve is supplied in large part by choroidal circulation.

Techniques to Measure Ocular Blood Flow A number of techniques have been developed to assess ocular blood flow. They include laser speckle flowgraphy, color Doppler imaging, Doppler Fourier domain optical coherence tomography, laser Doppler velocimetry, confocal scanning laser Doppler flowmetry, and retinal functional imaging.1,

Laser Speckle Flowgraphy Laser speckle is detected when a coherent light source such as laser light is dispersed from a diffusing surface such as retinal and choroidal vessels and the circulation of the optic nerve head. The varying patterns of light can be used to determine red blood cell velocity and retinal blood flow. However, due to differences in the tissue structure in different eyes, flux values cannot be used for comparisons between eyes. This limitation may be overcome by subtracting background choroidal blood flow results from the overall blood flow results in the region of interest.

Color Doppler Imaging Color Doppler imaging has also been investigated as a technique to measure the blood flow velocity in the retinal and choroidal arteries. This technique delivers ultrasound in pulsed Doppler mode with a transducer set on closed eyelids. The examination takes 30 to 40 minutes and is most effective for the mean velocity of large ophthalmic vessels such as the ophthalmic artery, the central retinal artery, and the short posterior ciliary arteries. However, total blood flow cannot be determined with this technique, and imaging is highly dependent on probe placement.

Doppler Fourier Domain Optical Coherence Tomography Doppler Fourier domain optical coherence tomography is a noncontact imaging technique that detects the intensity of the light scattered back from erythrocytes as they move in the vessels of the ocular tissue. This induces a frequency shift that represents the velocity of the blood in the ocular tissue.

Laser Doppler Velocimetry Laser Doppler velocimetry compares the frequency of reflected laser light from a moving particle with stationary tissue.

Confocal Scanning Laser Doppler Flowmetry Confocal scanning laser Doppler flowmetry combines laser Doppler flowmetry with confocal scanning laser tomography. Infrared laser light is used to scan the retina, and the frequency and amplitude of Doppler shifts are determined from the reflected light. Determinations of blood velocity and blood volume are used to compute the total blood flow and create a physical map of retinal flow values.

Summary Description Several techniques have been developed to measure the thickness of the optic nerve and retinal nerve fiber layer as a method to diagnose glaucoma. Measurement of ocular blood flow is also being evaluated as a diagnostic tool for glaucoma.

Summary of Evidence For individuals who have glaucoma or suspected glaucoma who receive imaging of the optic nerve and retinal nerve fiber layer, the evidence includes studies on diagnostic accuracy. Relevant outcomes are test accuracy, symptoms, morbid events, functional outcomes, and medication use. Confocal scanning laser ophthalmoscopy, scanning laser polarimetry, and optical coherence tomography can be used to evaluate the optic nerve and retinal nerve fiber layer in patients with glaucoma and suspected glaucoma. Numerous articles have described findings from patients with known and suspected glaucoma using confocal scanning

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laser ophthalmoscopy, scanning laser polarimetry, and optical coherence tomography. These studies have reported that abnormalities may be detected on these examinations before functional changes are noted. The literature and specialty society guidelines have indicated that optic nerve analysis using confocal scanning laser ophthalmoscopy, scanning laser polarimetry, and optical coherence tomography are established add-on tests that may be used to diagnose and manage patients with glaucoma and suspected glaucoma. These results are often considered along with other findings to make diagnostic and therapeutic decisions about glaucoma care, including the use of topical medication, monitoring, and surgery to lower intraocular pressure. Thus, an accurate diagnosis of glaucoma would be expected to reduce the progression of glaucoma. The evidence is sufficient to determine that the technology results in an improvement in the net health outcome.

For individuals who have glaucoma or suspected glaucoma who receive an evaluation of ocular blood flow, the evidence includes association studies. Relevant outcomes are test accuracy, symptoms, morbid events, functional outcomes, and medication use. Techniques to measure ocular blood flow or ocular blood velocity are used to determine appropriate glaucoma treatment options. The data for these techniques remain limited. Literature reviews have not identified studies addressing whether these technologies improve diagnostic accuracy or whether they improve health outcomes in patients with glaucoma. Some have suggested that these parameters may inform understanding of the variability in visual field changes in patients with glaucoma (ie, they may help explain why patients with similar levels of intraocular pressure develop markedly different visual impairments). However, data on the use of ocular blood flow, pulsatile ocular blood flow, and/or blood flow velocity are currently lacking. The evidence is insufficient to determine that the technology results in an improvement in the net health outcome.

Several techniques have been developed to measure the thickness of the optic nerve and retinal nerve fiber layer as a method to diagnose glaucoma. Measurement of ocular blood flow is also being evaluated as a diagnostic tool for glaucoma.

For individuals who have glaucoma or suspected glaucoma who receive imaging of the optic nerve and retinal nerve fiber layer, the evidence includes studies on diagnostic accuracy. Relevant outcomes are test accuracy, symptoms, morbid events, functional outcomes, and medication use. Confocal scanning laser ophthalmoscopy, scanning laser polarimetry, and optical coherence tomography can be used to evaluate the optic nerve and retinal nerve fiber layer in patients with glaucoma and suspected glaucoma. Numerous articles have described findings from patients with known and suspected glaucoma using confocal scanning laser ophthalmoscopy, scanning laser polarimetry, and optical coherence tomography. These studies have reported that abnormalities may be detected on these examinations before functional changes are noted. The literature and specialty society guidelines have indicated that optic nerve analysis using confocal scanning laser ophthalmoscopy, scanning laser polarimetry, and optical coherence tomography are established add-on tests that may be used to diagnose and manage patients with glaucoma and suspected glaucoma. These results are often considered along with other findings to make diagnostic and therapeutic decisions about glaucoma care, including use of topical medication, monitoring, and surgery to lower intraocular pressure. Thus, accurate diagnosis of glaucoma would be expected to reduce the progression of glaucoma. The evidence is sufficient to determine that the technology results in a meaningful improvement in the net health outcome.

For individuals who have glaucoma or suspected glaucoma who receive an evaluation of ocular blood flow, the evidence includes association studies. Relevant outcomes are test accuracy, symptoms, morbid events, functional outcomes, and medication use. Techniques to measure ocular blood flow or ocular blood velocity are used to determine appropriate glaucoma treatment options. The data for these techniques remain limited. Literature reviews have not identified studies addressing whether these technologies improve diagnostic accuracy or whether they improve health outcomes in patients with glaucoma. Some have suggested that these parameters may inform understanding of the variability in visual field changes in patients with glaucoma (ie, they may help explain why patients with similar levels of intraocular pressure develop markedly different visual impairments). However, data on the use of ocular blood flow, pulsatile ocular blood flow, and/or blood flow velocity are currently lacking. The evidence is insufficient to determine that the technology results in an improvement in the net health outcome.

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Policy History Date Action 5/2026 Annual policy review. Policy updated with literature review through January 20, 2026; no references added. Policy statements unchanged. 5/2025 Annual policy review. Policy updated with literature review through January 31, 2025; no references added. Policy statements unchanged. 1/2025 Clarified coding information. 5/2024 Annual policy review. References updated. Policy statements unchanged. 5/2023 Annual policy review. Minor editorial refinements to policy statements; intent unchanged. 4/2022 Annual policy review. Description, summary, and references updated. Policy statements unchanged. 4/2021 Annual review. Policy statements unchanged. 1/2021 Medicare information removed. See MP #132 Medicare Advantage Management for local coverage determination and national coverage determination reference.
5/2020 Annual review. Description, summary, and references updated. Policy statements unchanged. 4/2019 Annual review. Description, summary, and references updated. Policy statements unchanged. 4/2018 Annual review. New references added. Summary clarified. 5/2017 Annual review. Doppler ultrasonography removed from the third policy statement. The intent of the policy statement is unchanged. Title changed. 12/2016 Clarified coding information. 11/2016 Clarified coding information. 10/2016 Annual review. New references added. 10/2016 Clarified coding information.
4/2015 Clarified coding information. 3/2015 Annual review. New references added. 9/2014 Coding information clarified. 6/2014 Updated Coding section with ICD10 procedure and diagnosis codes, effective 10/2015. 5/2014 Annual review. New references added 4/2014 Clarified coding information. 11/2011-4/2012 Medical policy ICD 10 remediation: Formatting, editing, and coding updates. No changes to policy statements.
4/2011 Annual review. Changes to policy statements.
2/2011 Reviewed - Medical Policy Group - Psychiatry and Ophthalmology. No changes to policy statements. 1/2011 Annual review. No changes to policy statements. 2/2010 Reviewed - Medical Policy Group - Psychiatry, Ophthalmology, Pediatrics and Endocrinology. No changes to policy statements. 10/2009 Annual review. Changes to policy statements.
2/2009 Annual review. Changes to policy statements.
2/2009 Annual review. Changes to policy statements.
2/2009 Reviewed - Medical Policy Group - Psychiatry, Ophthalmology, and Endocrinology.
No changes to policy statements. 11/2008 Medical Policy 053 describing covered and non-covered indications. Effective 11/01/2008.
11/2008 Annual review. Changes to policy statements.
8/2008 Annual review. Changes to policy statements. 2/2007 Reviewed - Medical Policy Group - Psychiatry, Ophthalmology, and Endocrinology.
No changes to policy statements. 7/2006 Annual review. Changes to policy statements.

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Information Pertaining to All Blue Cross Blue Shield Medical Policies Click on any of the following terms to access the relevant information: Medical Policy Terms of Use Managed Care Guidelines Indemnity/PPO Guidelines Clinical Exception Process Medical Technology Assessment Guidelines

References

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2. Ervin AM, Boland MV, Myrowitz EH, et al. Screening for Glaucoma: Comparative Effectiveness (Comparative Effectiveness Review No. 59). Rockville, MD: Agency for Healthcare Research and Quality; 2012.
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8. Bafa M, Lambrinakis I, Dayan M, et al. Clinical comparison of the measurement of the IOP with the ocular blood flow tonometer, the Tonopen XL and the Goldmann applanation tonometer. Acta Ophthalmol Scand. Feb 2001; 79(1): 15-8. PMID 11167279
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13. Aizawa N, Yokoyama Y, Chiba N, et al. Reproducibility of retinal circulation measurements obtained using laser speckle flowgraphy-NAVI in patients with glaucoma. Clin Ophthalmol. 2011; 5: 1171-6. PMID 21887100
14. Gardiner SK, Cull G, Fortune B, et al. Increased Optic Nerve Head Capillary Blood Flow in Early Primary Open-Angle Glaucoma. Invest Ophthalmol Vis Sci. Jul 01 2019; 60(8): 3110-3118. PMID 31323681
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17. Association between mitochondrial DNA damage and ocular blood flow in patients with glaucoma. Br J Ophthalmol. Aug 2019; 103(8): 1060-1065. PMID 30190366
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19. Kiyota N, Shiga Y, Suzuki S, et al. The Effect of Systemic Hyperoxia on Optic Nerve Head Blood Flow in Primary Open-Angle Glaucoma Patients. Invest Ophthalmol Vis Sci. Jun 01 2017; 58(7): 3181-3188. PMID 28654983

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18. Kiyota N, Kunikata H, Shiga Y, et al. Ocular microcirculation measurement with laser speckle flowgraphy and optical coherence tomography angiography in glaucoma. Acta Ophthalmol. Jun 2018; 96(4): e485-e492. PMID 29575676
19. Kobayashi W, Kunikata H, Omodaka K, et al. Correlation of optic nerve microcirculation with papillomacular bundle structure in treatment naive normal tension glaucoma. J Ophthalmol. 2014; 2014: 468908. PMID 25574382
20. Kohmoto R, Sugiyama T, Ueki M, et al. Correlation between laser speckle flowgraphy and optical coherence tomography angiography measurements in normal and glaucomatous eyes. Clin Ophthalmol. 2019; 13: 1799-1805. PMID 31571818
21. Kuroda F, Iwase T, Yamamoto K, et al. Correlation between blood flow on optic nerve head and structural and functional changes in eyes with glaucoma. Sci Rep. Jan 20 2020; 10(1): 729. PMID 31959837
22. Mursch-Edlmayr AS, Luft N, Podkowinski D, et al. Laser speckle flowgraphy derived characteristics of optic nerve head perfusion in normal tension glaucoma and healthy individuals: a Pilot study. Sci Rep. Mar 28 2018; 8(1): 5343. PMID 29593269
23. Mursch-Edlmayr AS, Luft N, Podkowinski D, et al. Differences in Optic Nerve Head Blood Flow Regulation in Normal Tension Glaucoma Patients and Healthy Controls as Assessed With Laser Speckle Flowgraphy During the Water Drinking Test. J Glaucoma. Jul 2019; 28(7): 649-654. PMID 30950964
24. Mursch-Edlmayr AS, Pickl L, Calzetti G, et al. Comparison of Neurovascular Coupling between Normal Tension Glaucoma Patients and Healthy Individuals with Laser Speckle Flowgraphy. Curr Eye Res. Nov 2020; 45(11): 1438-1442. PMID 32255706
25. Shiga Y, Kunikata H, Aizawa N, et al. Optic Nerve Head Blood Flow, as Measured by Laser Speckle Flowgraphy, Is Significantly Reduced in Preperimetric Glaucoma. Curr Eye Res. Nov 2016; 41(11): 1447-1453. PMID 27159148
26. Takeyama A, Ishida K, Anraku A, et al. Comparison of Optical Coherence Tomography Angiography and Laser Speckle Flowgraphy for the Diagnosis of Normal-Tension Glaucoma. J Ophthalmol. 2018; 2018: 1751857. PMID 29651339
27. Abegão Pinto L, Willekens K, Van Keer K, et al. Ocular blood flow in glaucoma - the Leuven Eye Study. Acta Ophthalmol. Sep 2016; 94(6): 592-8. PMID 26895610
28. Kurysheva NI, Parshunina OA, Shatalova EO, et al. Value of Structural and Hemodynamic Parameters for the Early Detection of Primary Open-Angle Glaucoma. Curr Eye Res. Mar 2017; 42(3): 411-417. PMID 27341295
29. Witkowska KJ, Bata AM, Calzetti G, et al. Optic nerve head and retinal blood flow regulation during isometric exercise as assessed with laser speckle flowgraphy. PLoS One. 2017; 12(9): e0184772. PMID 28898284
30. Rusia D, Harris A, Pernic A, et al. Feasibility of creating a normative database of colour Doppler imaging parameters in glaucomatous eyes and controls. Br J Ophthalmol. Sep 2011; 95(9): 1193-8. PMID 21106991
31. Calvo P, Ferreras A, Polo V, et al. Predictive value of retrobulbar blood flow velocities in glaucoma suspects. Invest Ophthalmol Vis Sci. Jun 22 2012; 53(7): 3875-84. PMID 22589447
32. Gedde SJ, Vinod K, Wright MM, et al. Primary Open-Angle Glaucoma Preferred Practice Pattern®. Ophthalmology. Jan 2021; 128(1): P71-P150. PMID 34933745
33. Gedde SJ, Lind JT, Wright MM, et al. Primary Open-Angle Glaucoma Suspect Preferred Practice Pattern®. Ophthalmology. Jan 2021; 128(1): P151-P192. PMID 34933743
34. Mangione CM, Barry MJ, Nicholson WK, et al. Screening for Primary Open-Angle Glaucoma: US Preventive Services Task Force Recommendation Statement. JAMA. May 24 2022; 327(20): 1992-

35. PMID 35608574

    Endnotes

    1 Based on expert opinion