Asset Publisher


print Print Back Back

Corneal Hysteresis

Policy Number: MP-354

Latest Review Date:  April 2024

Category: Vision                                                              


Corneal hysteresis measurement is considered investigational.


Corneal hysteresis (CH) measurement assesses corneal resistance to deformation. CH has been proposed as a possible indicator of the viscoelastic properties in the cornea. The Ocular Response Analyzer® (ORA) is an instrument that measures CH by using a rapid air impulse to apply force to the cornea. An advanced electro-optical system then monitors the deformation. Two independent pressure values are derived from the inward and outward applanation events. The difference between these two pressure values is CH. Low CH demonstrates that the cornea is less capable of absorbing (damping) the energy of the air pulse. Abnormalities in CH have been detected in a variety of corneal diseases, including keratoconus, Fuchs' dystrophy, and in individuals who have had laser in situ keratomileusis (LASIK). Glaucoma is another potential indication for CH measurement. The preferred method of measuring intraocular pressure (IOP) is using a contact applanation method such as a Goldmann tonometer (GAT).


This policy is updated frequently. The most recent literature review was performed through April 15, 2024.

Summary of Evidence

Identified is a prospective observational cohort study to investigate the role of CH as a risk factor for development of glaucoma. The authors concluded that the decrease in CH measurements represents a risk factor for developing glaucoma. Study limitations included but were not limited to study design, lack of information on participants lost to follow up, as well as uncontrolled confounding by unmeasured factors, such as family history of glaucoma. Additionally, the study doesn’t test whether the use of CH improves care. Future studies should be performed to further clarify the clinical utility of using CH as part of glaucoma management on patient outcomes.

A 2018 Hayes report identified 16 studies that evaluated CH testing for diagnosis of glaucoma, or for predicting the progression or response to treatment of glaucoma. Eleven prospective or retrospective cohort studies and 5 prospective case-control studies were examined, involving from 52 to 443 patients with follow-up times ranging from zero to 6.6 years. The report concluded that the test has some capacity to diagnose glaucoma, to predict risk for glaucoma progression, and to predict response of glaucoma to certain types of treatment; however, the evidence is of very poor quality and lacked the rigor to determine diagnostic or prognostic accuracy. The role of CH testing in the management of patients with glaucoma and its impact on long-term health outcomes could not be determined due to the lack of evidence on the clinical utility of this test. Additional studies are needed.

Current evidence for corneal hysteresis measurement focuses on the risk, diagnosis and progression of glaucoma however, these studies do not demonstrate how corneal hysteresis measurement influences clinical management or outcomes. Additional clinical trials are necessary to determine its benefit in clinical practice. The evidence is insufficient to determine that the technology results in an improvement in the net health outcome.

Practice Guidelines and Position Statements

American Academy of Ophthalmology (AAO)

The AAO Preferred Practice Pattern (PPP) for POAG states that CH, which is a measure of the viscoelastic dampening of the cornea, has been shown to be associated with the risk of glaucoma progression. In addition, it states that low CH is associated with glaucoma progression (2021).

U.S. Preventive Services Task Force Recommendations

Not applicable.


Glaucoma, corneal hysteresis, corneal, intraocular pressure, IOP, primary open angle glaucoma, POAG, keratoconus, Goldmann tonometer, Reichert Ocular Response Analyzer, ORA, ORA G3, Ocular Response Analyzer


The Ocular Response Analyzer® (ORA) by Reichert Inc. received FDA clearance for the intended use to measure intra-ocular pressure of the eye and the biomechanical response of the cornea for the purpose of aiding in the diagnosis and monitoring of glaucoma in January 2004.


Coverage is subject to member’s specific benefits. Group-specific policy will supersede this policy when applicable.

ITS: Home Policy provisions apply

FEP contracts: Special benefit consideration may apply. Refer to member’s benefit plan.


CPT Codes:


Corneal hysteresis determination, by air impulse stimulation, unilateral or bilateral, with interpretation and report



  1. Bayer A, Sahin A, Hürmeric V, et al. Intraocular pressure values obtained by ocular response analyzer, dynamic contour tonometry, and Goldmann tonometry in keratokonic corneas.  J Glaucoma.  2010 Oct-Nov; 19(8):540-5.
  2. Bayoumi NH, Bessa AS, El Massry AA.  Ocular response analyzer and Goldmann applanation tonometry: a comparative study of findings.  J Glaucoma. 2010 Dec; 19(9):627-31.
  3. Bochmann F, Ang GS and Azuara-Blanco A.  Lower corneal hysteresis in glaucoma patients with acquired pit of the optic nerve (APON).  Graefes Arch Clin Exp Ophthalmol, May 2008; 246(5): 735-738.
  4. Carbonaro F, Andrew T, Mackey DA, et al.  Comparison of three methods of intraocular pressure measurement and their relation to central corneal thickness. Eye (Lond). 2010 Jul; 24(7):1165-70.
  5. Congdon NG, Broman AT, et al.  Central corneal thickness and corneal hysteresis associated with glaucoma damage.  American Journal of Ophthalmology, May 2006, Vol. 141, Issue 5.
  6. ECRI Institute. Hotline Response. Central Corneal thickness measurement for the diagnosis of glaucoma and ocular hypertension.  April 2010.
  7. Elsheikh A, Wang D, Rama P, et al.  Experimental assessment of human corneal hysteresis.  Curr Eye Res, March 2008; 33(3): 205-213.
  8. Fontes BM, Ambrósio R Jr, Velarde GC, et al. Ocular response analyzer measurements in keratoconus with normal central corneal thickness compared with matched normal control eyes.  J Refract Surg, 2011 Mar; 27(3):209-15.
  9. Gatinel D, Chaabouni S, Adam PA, Munck J, et al.  Corneal hysteresis, resistance factor, topography, and pachymetry after corneal lamellar flap.  J Refract Surg, January 2007; 23(1): 76-84.
  10. Hager A, Loge K, Kutschan A and Wiegand W.  [The effect of cataract and vitreoretinal surgery on central corneal thickness and corneal hysteresis].  Klin Monatsbl Augenheilkd, March 2008; 225(3): 207-211.
  11. Hayes, Inc. Medical Technology Directory. Measurement of Corneal Hysteresis for the Diagnosis and Management of Glaucoma. Lansdale, PA: Hayes, Inc.; December 6, 2018.
  12. IOM (Institute of Medicine). 2011. Clinical Practice Guidelines We Can Trust. Washington, DC: The National Academies Press.
  13. Janulevičiene I, Ehrlich R, Siesky B, et al. Evaluation of hemodynamic parameters as predictors of glaucoma progression. J Ophthalmol. 2011; 2011:164320.
  14. Jorge JM, Gonzalez-Meijome JM, et al.  Correlations between corneal biomechanical properties measured with the ocular response analyzer and ICare rebound tonometry.  J Glaucoma, Sept 2008; 17(6): 442-448.
  15. Katiyar S, Tong J, Pensyl D, Sullivan-Mee M. Corneal Biomechanical Changes Caused by Acute Elevation of IOP in Eyes with and without Glaucoma. Optom Vis Sci. 2021;98(4):367-373.
  16. Kirwan Caitriona, O’keefe Michael and Lanigan Bernadette.  Corneal hysteresis and intraocular pressure measurement in children using the Reichert Ocular Response Analyzer.  American Journal of Ophthalmology, December 2006, Vol. 142, Issue 6.
  17. Kopito R, Gaujoux T, Montard R, et al.  Reproducibility of viscoelastic property and intraocular pressure measurements obtained with the Ocular Response Analyzer.  Acta Ophthalmol. 2010 Aug 25.
  18. Kotecha A, Elsheikh A, Roberts CR, et al.  Corneal thickness- and age-related biomechanical properties of the cornea measured with the ocular response analyzer.  IOVS, December 2006, Vol. 47, No. 12.
  19. Kotecha A.  What biomechanical properties of the cornea are relevant for the clinician?  Surv Ophthalmol, November 2007; 52 Suppl 2: S109-114.
  20. Lam A, Chen D, Chiu R and Chui WS.  Comparison of IOP measurements between ORA and GAT in normal Chinese.  Optom Vis Sci, September 2007; 84(9): 909-914.
  21. Lau W, Pye D.  Changes in corneal biomechanics and applanation tonometry with induced corneal swelling.  Invest Ophthalmol Vis Sci. 2011 Feb 23.
  22. Lu F, Xu S, Qu J, Shen M, Wang X, et al.  Central corneal thickness and corneal hysteresis during corneal swelling induced by contact lens wear with eye closure.  Am J Ophthalmol, April 2007; 143(4): 616-622.
  23. Mangouritsas G, Morphis G, Mourtzoukos S, et al.  Association between corneal hysteresis and central corneal thickness in glaucomatous and non-glaucomatous eyes.  Acta Ophthalmol.  2009 Nov; 87(8):901-5.
  24. Martinez-de-la-Casa J, Garcia-Feijoo J, et al.  Ocular response analyzer versus Goldmann applanation tonometry for intraocular pressure measurements.  IOVS, October 2006, Vol. 47, No. 10.
  25. Medeiros FA and Weinreb RN.  Evaluation of the influence of corneal biomechanical properties on intraocular pressure measurements using the ocular response analyzer.  J Glaucoma 2006; 15(5): 364-370.
  26. Murphy ML, Pokrovskaya O, Galligan M, et al. Corneal hysteresis in patients with glaucoma-like optic discs, ocular hypertension and glaucoma. BMC Ophthalmol. 2017 Jan 10; 17(1):1.
  27. Ortiz D, Shabayek MH, et al.  Corneal biomechanical properties in normal, post-laser in situ keratomileusis, and keratoconic eyes.  Cataract Refract Surg, August 2007; 33(8): 1371-1375.
  28. Pepose JS, Feigenbaum SK, Qazi MA, et al.  Changes in corneal biomechanics and intraocular pressure following LASIK using static, dynamic, and noncontact tonometry.  American Journal of Ophthalmology, January 2007, Vol. 143, Issue 1.
  29. Prum BE Jr, Herndon LW Jr, Moroi SE, et al. Primary Angle Closure Preferred Practice Pattern (®) Guidelines. Ophthalmology. 2016 Jan; 123(1):P1-P40.
  30. Renier C, Zeyen T, Fieuws S, et al.  Comparison of ocular response analyzer, dynamic contour tonometer and Goldmann applanation tonometer Int Ophthalmol. 2010 Dec; 30(6):651-9.
  31. Saad A, Lteif Y, Azan E, et al.  Biomechanical properties of keratoconus suspect eyes.  Invest Ophthalmos Vis Sci. 2009 Dec 30.
  32. Schweitzer C, Roberts CJ, Mahmoud AM, et al.  Screening of forme gruste keratoconus with the ocular response analyzer. Invest Ophthalmol Vis Sci.  2010 May; 51(5):2403-10.
  33. Shah S, Laiquzzaman M, Bhojwani R, Mantry S and Cunliffe I.  Assessment of the biomechanical properties of the cornea with the ocular response analyzer in normal and keratoconic eyes.  Investigative Ophthalmology & Visual Science, July 2007; 48(7): 3026-3031.
  34. Shah S, Laiquzzaman M, Cunliffe I and Mantry S.  The use of the Reichert ocular response analyser to establish the relationship between ocular hysteresis, corneal resistance factor and central corneal thickness in normal eyes.  Cont Lens Anterior Eye, December 2006; 29(5): 257-262.
  35. Shah S, Laiquzzaman M, Mantry S and Cunliffe I.  Ocular response analyser to assess hysteresis and corneal resistance factor in low tension, open angle glaucoma and ocular hypertension.  Clin Experiment Ophthalmol, August 2008; 36(6): 508-513.
  36. Sullivan-Mee M, Billingsley SC, Patel AD, Halverson KD, et al.  Ocular Response Analyzer in subjects with and without glaucoma.  Optom Vis Sci, June 2008; 85(6): 463-470.
  37. Sullivan-Mee M, Gerhardt G, Halverson KD, et al.  Repeatability and reproducibility for intraocular pressure measurement by dynamic contour, ocular response analyzer and Goldmann applanation tonometry. J Glaucoma.  2009 Dec: 18(9):666-73.
  38. Sun L, Shen M, Wang J et al.  Recovery of corneal hysteresis after reduction of intraocular pressure in chronic primary angle-closure glaucoma.  Am J Ophthalmol.  2009 Jun: 147(6):1061-6., 1066.e1-2.
  39. Susanna CN, Diniz-Filho A, Daga FB, et al. A Prospective Longitudinal Study to Investigate Corneal Hysteresis as a Risk Factor for Predicting Development of Glaucoma. Am J Ophthalmol. 2018 Mar; 187:148-152.
  40. Touboul D, Roberts C, Kerautret J, Garra C, et al.  Correlations between corneal hysteresis, intraocular pressure, and corneal central pachymetry.  J Cataract Refract Surgery 2008; 34(4): 616-622.
  41. Vandewalle E, Vandenbroeck S, Stalmans I, et al. Comparison of ICare, dynamic contour tonometer, and ocular response analyzer with Goldmann applanation tonometer in patients with glaucoma,  Eur J Ophthalmol. 2009 Sep-Oct; 19(5):783-9.
  42. Zhang C, Tatham AJ, Abe RY, et al. Corneal hysteresis and progressive retinal nerve fiber layer loss in glaucoma. Am J Ophthalmol. 2016 Mar 3. pii: S0002-9394(16)30084-8.


Medical Policy Group, April 2009 (1)

Medical Policy Administration Committee, May 2009

Available for comment May 12-June 24, 2009

Medical Policy Group, July 2011; Updated Key Points and References

Medical Policy Group, September 2012: Effective September 14, 2012 this policy is no longer scheduled for regular literature reviews and updates.

Medical Policy Group, November 2014: 2015 Annual Coding update. Added code 92145 to current coding and added Previous Coding section to include deleted code 0181T.

Medical Policy Group, December 2019 (6): Updates to Description, Key Points, Governing Bodies, Key Words (Goldmann tonometer) and References. No change to policy intent.

Medical Policy Group, March 2021 (9): Updates to Description, Key Points, References. Policy statement updated to remove “not medically necessary,” no change to policy intent.

Medical Policy Group, March 2023 (9): Updates to Key Points and Benefit Application. Reviewed by consensus. No new published peer-reviewed literature available that would alter the coverage statement in this policy.  

Medical Policy Group, April 2024 (9): Reviewed by consensus. Updates to Key Points; Practice Guidelines and Position Statements, Key Words: ORA G3, Benefit Application, and References. No new published peer-reviewed literature available that would alter the coverage statement in this policy.  

This medical policy is not an authorization, certification, explanation of benefits, or a contract. Eligibility and benefits are determined on a case-by-case basis according to the terms of the member’s plan in effect as of the date services are rendered. All medical policies are based on (i) research of current medical literature and (ii) review of common medical practices in the treatment and diagnosis of disease as of the date hereof. Physicians and other providers are solely responsible for all aspects of medical care and treatment, including the type, quality, and levels of care and treatment.

This policy is intended to be used for adjudication of claims (including pre-admission certification, pre-determinations, and pre-procedure review) in Blue Cross and Blue Shield’s administration of plan contracts.

The plan does not approve or deny procedures, services, testing, or equipment for our members. Our decisions concern coverage only. The decision of whether or not to have a certain test, treatment or procedure is one made between the physician and his/her patient. The plan administers benefits based on the member’s contract and corporate medical policies. Physicians should always exercise their best medical judgment in providing the care they feel is most appropriate for their patients. Needed care should not be delayed or refused because of a coverage determination.

As a general rule, benefits are payable under health plans only in cases of medical necessity and only if services or supplies are not investigational, provided the customer group contracts have such coverage.

The following Association Technology Evaluation Criteria must be met for a service/supply to be considered for coverage:

1. The technology must have final approval from the appropriate government regulatory bodies;

2. The scientific evidence must permit conclusions concerning the effect of the technology on health outcomes;

3. The technology must improve the net health outcome;

4. The technology must be as beneficial as any established alternatives;

5. The improvement must be attainable outside the investigational setting.

Medical Necessity means that health care services (e.g., procedures, treatments, supplies, devices, equipment, facilities or drugs) that a physician, exercising prudent clinical judgment, would provide to a patient for the purpose of preventing, evaluating, diagnosing or treating an illness, injury or disease or its symptoms, and that are:

1. In accordance with generally accepted standards of medical practice; and

2. Clinically appropriate in terms of type, frequency, extent, site and duration and considered effective for the patient’s illness, injury or disease; and

3. Not primarily for the convenience of the patient, physician or other health care provider; and

4. Not more costly than an alternative service or sequence of services at least as likely to produce equivalent therapeutic or diagnostic results as to the diagnosis or treatment of that patient’s illness, injury or disease.