Journal of Current Glaucoma Practice

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VOLUME 14 , ISSUE 1 ( January-April, 2020 ) > List of Articles

Original Article

Identification and Quantitative Assessment of Schlemm's Canal in the Eyes with 360° Angle Recession Glaucoma

Tarannum Mansoori, Appidi Abhinav Reddy

Keywords : Angle recession glaucoma, Anterior segment optical coherence tomography, Schlemm's canal

Citation Information : Mansoori T, Reddy AA. Identification and Quantitative Assessment of Schlemm's Canal in the Eyes with 360° Angle Recession Glaucoma. J Curr Glaucoma Pract 2020; 14 (1):25-29.

DOI: 10.5005/jp-journals-10078-1272

License: CC BY-NC 4.0

Published Online: 01-04-2019

Copyright Statement:  Copyright © 2020; The Author(s).


Synopsis: Angle recession, trabecular meshwork injury, increased trabecular pigmentation, and reduced Schlemm's canal dimensions can cause reduced aqueous outflow and unilateral glaucoma in an eye, following blunt trauma. Also, these patients are possibly at a risk to develop raised intraocular pressure (IOP) in the normal fellow eye due to reduced Schlemm's canal area. Aim: To identify and quantitatively evaluate Schlemm's canal (SC) parameters by anterior segment optical coherence tomography (AS-OCT) in the patients with unilateral 360° angle recession glaucoma (ARG) and compare with the fellow normal eyes and age-related normal control. Materials and methods: Six patients with a history of unilateral ocular blunt trauma and unilateral 360° ARG, normal fellow eyes and 34 age-matched normal controls underwent anterior chamber angle imaging with corneal line scan protocol using AS-OCT. Schlemm's canal cross-sectional area (SC-CSA) and meridional and coronal diameters were measured on temporal and nasal sections at 3 and 9 o'clock positions. Results: In the AS-OCT cross-sectional images, SC was observed as a horizontally oval or ellipsoidal translucent space. The mean SC-CSA (1,710 ± 376.1 μm2 vs 6,100 ± 2,700 μm2, p < 0.0001), mean meridional diameter (243.6 ± 55.47 μm vs 474 ± 125.6 μm, p < 0.0001), and mean coronal diameter (32.68 ± 6.27 μm vs 57.42 ± 16.27 μm, p < 0.0001) of the SC were smaller in ARG eyes when compared with the normal eyes. The SC dimensions were reduced in the untraumatized fellow eyes of ARG patients when compared with the normal eyes (SC-SCA: 2350 ± 602.1 μm2, p = 0.001, meridional diameter: 341.8 ± 88.8 μm, p = 0.012 and coronal diameter: 31.67 ± 3.8 μm, p < 0.0001). There was no difference in the measured SC dimensions between the ARG eyes and the normal fellow eyes. Conclusion: The reduced SC parameters in the eyes with unilateral 360° ARG and the normal fellow eyes could mean that these patients probably have an underlying structural abnormality in the SC. Trabecular meshwork injury, angle recession, and increased trabecular pigmentation are probably the predisposing factors in the ARG eyes for the increase in IOP. Whether the normal fellow eyes develop IOP rise in the future needs to be seen during regular follow-up.

  1. Herschler J. Trabecular damage due to blunt anterior segment injury and its relationship to traumatic glaucoma. Trans Am Acad Ophthalmol Otolaryngol 1977;;83(2)::239–248.
  2. Mooney D. Anterior chamber angle tears after non-perforating injury. Br J Ophthalmol 1972;56(5):418–424. DOI: 10.1136/bjo.56.5.418.
  3. Kaufman JH, Tolpin DW. Glaucoma after traumatic angle recession. A ten-year prospective study. Am J Ophthalmol 1974;78(4):648–654. DOI: 10.1016/s0002-9394(14)76303-2.
  4. Blanton FM. Anterior chamber angle recession and secondary glaucoma: a study of the after effects of traumatic hyphemas. Arch Ophthalmol 1964;72(1):39–44. DOI: 10.1001/archopht.1964.00970020041010.
  5. Mooney D. Angle recession and secondary glaucoma. Br J Ophthalmol 1973;57(8):608–612. DOI: 10.1136/bjo.57.8.608.
  6. Sihota R, Kumar S, Gupta V, et al. Early predictors of traumatic glaucoma after closed globe injury: trabecular pigmentation, widened angle recess, and higher baseline intraocular pressure. Arch Ophthalmol 2008;126(7):921–926. DOI: 10.1001/archopht.126.7.921.
  7. Alper MG. Contusion angle deformity and glaucoma. Arch Ophthalmol 1963;69(4):455–467. DOI: 10.1001/archopht.1963.00960040461007.
  8. Tonjum AM. Intraocular pressure and facility of outflow late after ocular contusion. Acta Ophthalmol 1968;46(5):886–908. DOI: 10.1111/j.1755-3768.1968.tb00927.x.
  9. Wolff SM, Zimmerman LE. Chronic secondary glaucoma associated with retrodisplacement of the iris root and deepening of anterior chamber angle secondary to contusion. Am J Ophthalmol 1962;54(4):547–563. DOI: 10.1016/0002-9394(62)92186-4.
  10. Jensen OA. Contusion angle recession, a histopathological study of a danish material. Acta Ophthalmol 1968;46(6):1207–1212. DOI: 10.1111/j.1755-3768.1968.tb05913.x.
  11. Iwamoto T, Witmer R, Landolt E. Light and electron microscopy in absolute glaucoma with pigment dispersion phenomena and contusion angle deformity. Am J Ophthalmol 1971;72(2):420–434. DOI: 10.1016/0002-9394(71)91315-8.
  12. Kagemann L, Nevins JE, Jan NJ, et al. Characterisation of Schlemm's canal cross-sectional area. Br J Ophthalmol 2014;98(Suppl 2):ii10-4. DOI: 10.1136/bjophthalmol-2013-304629.
  13. Allingham RR, de Kater AW, Ethier CR. Schlemm's canal and primary open angle glaucoma: correlation between Schlemm's canal dimensions and outflow facility. Exp Eye Res 1996;62(1):101–109. DOI: 10.1006/exer.1996.0012.
  14. Hong J, Xu J, Wei A, et al. Spectral-domain optical coherence tomographic assessment of Schlemm's canal in chinese subjects with primary open-angle glaucoma. Ophthalmology 2013;120(4):709–715. DOI: 10.1016/j.ophtha.2012.10.008.
  15. Mansoori T, Reddy AA, Tumati NC, et al. Assessment of Schlemm's canal in acute primary angle closure: an anterior segment optical coherence tomography study. Int Ophthalmol 2018(10). DOI: 10.1007/s10792-018-1052-6.
  16. Tesluk GC, Spaeth GL. The occurrence of primary open angle glaucoma in the fellow eye of patients with unilateral angle-cleavage glaucoma. Ophthalmology 1985;92(7):904–911. DOI: 10.1016/s0161-6420(85)33936-2.
  17. Spaeth GL. Traumatic hyphema, angle recession, dexamethasone hypertension, and glaucoma. Arch Ophthalmol 1967;78(6):714–721. DOI: 10.1001/archopht.1967.00980030716005.
  18. Tumbocon JA, Latina MA. Angle recession glaucoma. Int Ophthalmol Clin 2002;42(3):69–78. DOI: 10.1097/00004397-200207000-00009.
  19. Kagemann L, Wang B, Wollstein G, et al. IOP elevation reduces Schlemm's canal cross-sectional area. Invest Ophthalmol Vis Sci 2014;55(3):1805–1809. DOI: 10.1167/iovs.13-13264.
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