How to Diagnose and Treat Angle Recession Glaucoma

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					                                                                            Ophthalmic Pearls
                                                                                   GLAUCOMA




                                                          How to Diagnose and Treat
                                                          Angle-Recession Glaucoma
                                                   by sumalee boonyaleephan, md, and sarwat salim, md, facs
                                                    edited by sharon fekrat, md, and ingrid u. scott, md, mph




                             T
                                         raumatic glaucoma is a mul-       1                                          2
                                         tifactorial group of disorders
                                         that results from closed- or
                                         open-globe injuries. Al-
                                         though different underlying
                             mechanisms may be involved with the
                             initial injury, the resulting optic neu-
                             ropathy and visual field loss is second-     A CLOSER LOOK. The anterior segment        3
                             ary to elevated IOP from reduction in        exam shows anisocoria (1,2), with the
                             aqueous outflow through the trabecu-         left pupil showing mydriasis with seg-
                             lar meshwork. Secondary glaucoma af-         mental loss of pupillary ruff (2). On fur-
                             ter trauma is more likely to occur with      ther examination, widening of the ciliary
                             a closed-globe injury, but it is often       body band in the same eye was noted
                             underdiagnosed because its onset may         (3), indicating angle recession.
                             be delayed and the history of eye injury
                             may be remote or overlooked.                 dentation of the cornea forces posteri-        Less often, a hyalinized membrane
                                Angle recession is a common mani-         or and lateral displacement of aqueous      may cover the inner surface of the
                             festation of blunt ocular trauma and         humor, deepening the peripheral ante-       trabecular meshwork. This membrane
                             involves rupture of the ciliary body         rior chamber and increasing the diam-       may be continuous with Descemet’s
                             face, resulting in a tear between the        eter of the corneoscleral limbal ring.      membrane and may extend peripher-
                             longitudinal and circular fibers of          These resultant shock waves traversing      ally into the recessed angle and onto
                             the ciliary muscle. Angle recession is       the interior of the globe are responsible   the anterior surface of the iris. The
                             reported to occur in 20 to 94 percent        for other anterior segment damage ac-       membrane obstructs aqueous outflow,
                             of eyes after blunt trauma and is often      companying angle recession, such as         causing an open-angle form of glauco-
                             masked initially due to the presence of      pupillary sphincter tears, iridodialysis,   ma. In some cases, this membrane may
                             concomitant hyphema, which results           cyclodialysis and zonular tears.            contract, resulting in angle-closure
                             from shearing of the anterior ciliary            The shearing forces to the drain-       glaucoma.
                             arteries. Approximately 5 to 20 percent      age angle result in a tear between the
                             of eyes with angle recession develop         longitudinal and circular fibers of the            Clinical Course and Signs
                             angle-recession glaucoma.                    ciliary muscle. While the longitudinal      As mentioned previously, 5 to 20 per-
                                This brief review will discuss the        muscle insertion at the scleral spur        cent of eyes with angle recession de-
                             pathophysiology and clinical course          remains intact, the circular muscle is      velop angle-recession glaucoma. Onset
                             and signs of angle-recession glaucoma,       displaced posteriorly along with the        is extremely variable and may occur
                             along with differential diagnosis and        iris root and pars plicata. The resultant   soon after the initial trauma or even
                             treatment strategies.                        glaucoma is not due to angle recession      years later, indicating possibly separate
                                                                          per se, but is secondary to initial trau-   pathologic mechanisms.
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                                         Pathophysiology                  ma to the trabecular meshwork, with             The risk of developing angle-reces-
                             Blunt force to the globe causes an an-       subsequent degenerative changes and         sion glaucoma appears to be related
                             terior to posterior axial compression        scarring, which leads to obstruction of     to the extent of angle recession. Angle
                             with equatorial distension. Abrupt in-       aqueous outflow.                            recession of more than 180 degrees is

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      Ophthalmic Pearls


 4                                                      5                                      Three Options for Treatment
                                                                                          Medication. In the acute setting, treat-
                                                                                          ment should be directed at lowering
                                                                                          IOP and controlling inflammation.
                                                                                          Topical steroids and cycloplegic agents
                                                                                          are used to control inflammation
                                                                                          and pain. Aqueous suppressants are
                                                                                          preferred as initial IOP-lowering
                                                                                          agents. Prostaglandin analogs have a
                                                                                          theoretical benefit of bypassing the
A CLUE. Iridodialysis (4) was the clue to look for other findings. Gonioscopy re-         dysfunctional trabecular meshwork by
vealed angle recession and patchy trabecular meshwork pigmentation (5).                   increasing uveoscleral outflow. Miot-
                                                                                          ics should be avoided because they can
deemed a considerable risk for second-       fected and the nontraumatized eye or         cause a paradoxical rise in IOP, pre-
ary glaucoma, although glaucoma can          in different quadrants of the involved       sumably due to a reduction in uveo-
develop when the area of recession is        eye. Widening of the ciliary body band       scleral outflow.
smaller than this.                           may be present due to retrodisplace-             Laser. Laser trabeculoplasty is not
    In one study, researchers found that     ment of the iris root. Other signs           effective in angle-recession glaucoma
approximately 50 percent of patients         include irregular and darker pigmen-         due to distortion of the angle anatomy
with traumatic glaucoma developed            tation in the angle, whitening of the        and trabecular meshwork scarring. An
open-angle glaucoma in the unaffect-         scleral spur due to visibly fractured iris   alternative laser procedure, Nd:YAG
ed, contralateral eye, suggesting that       processes, or the presence of peripheral     laser trabeculopuncture, has produced
these patients may have an underlying        anterior synechiae.                          variable success rates, with better re-
genetic predisposition to developing             Gonioscopy may aid in the diagno-        sponses seen in cases where some tra-
glaucoma, which may be accelerated by        sis of other angle abnormalities from        becular meshwork structure was intact
a traumatic insult.1                         trauma, such as iridodialysis or cyclo-      on gonioscopy, permitting penetration
    IOP may rise immediately after the       dialysis. It’s essential to note that, in    into Schlemm’s canal with an increase
injury, as a result of associated comor-     some cases, the gonioscopic findings         in aqueous outflow facility.
bidities such as hyphema, iridocyclitis      may become more difficult to recog-              Surgery. Filtration surgery has a
or pupillary block from ectopia lentis       nize with the passage of time.               lower success rate in angle-recession
(with or without vitreous prolapse).             Posterior segment examination will       glaucoma than it does in primary
    In some cases, IOP may be low            detect abnormalities that may also be        open-angle glaucoma. The adjunctive
secondary to decreased production            present, and a dilated fundus exam           use of antimetabolites can improve the
of aqueous humor from associated             should be performed after gonioscopy.        success of trabeculectomy. Research-
inflammation, a transient increase in                                                     ers have found greater IOP reduction
aqueous outflow facility from disrup-                 Differential Diagnosis              in cases where antimetabolites were
tion of structures in the angle, or the      After the trauma occurs, elevated IOP        employed with trabeculectomy than in
presence of a cyclodialysis cleft.           may be secondary to obstruction of           trabeculectomy alone or Molteno tube
    Anterior segment examination is          the trabecular meshwork by red blood         implantation alone.2
important. Once the acute inflamma-          cells, inflammatory cells or pigmented           Glaucoma drainage devices have
tion and hyphema resolve, attention          cells. Later, ghost-cell glaucoma may        demonstrated some benefit, but their
should be paid to the anterior cham-         develop from long-standing vitreous          success rates are lower in angle-reces-
ber depth of the affected eye, which         hemorrhage and a disrupted anterior          sion glaucoma than with other types of
may appear deeper. The meticulous            hyaloid face or an open posterior cap-       glaucomas. In eyes with limited visual
physician will also look for other ab-       sule. Chronic treatment with steroids        potential, a cyclodestructive procedure
normalities encountered with trauma,         can lead to steroid-induced glaucoma.        may be an alternative option.
such as iris sphincter tears, mydriasis,        Although the diagnosis of angle-
iris atrophy, iridoschisis, iridodonesis,    recession glaucoma is evident after                         Summary
phacodonesis and a subluxated lens.          careful gonioscopy and optic nerve ex-       A patient who has experienced blunt
    Gonioscopy, a simple diagnostic          amination, other differential diagnoses      ocular trauma should receive a com-
test, is essential for making the clinical   for unilateral glaucoma should be con-       prehensive eye exam to check for the
diagnosis of angle recession. It is usu-     sidered. These include—but are not           presence of angle recession and other
                                                                                                                                     s a r w at s a l i m , m d




ally deferred for four to six weeks after    limited to—pseudoexfoliative glau-           abnormalities. The risk of angle-re-
the acute injury. When gonioscopy is         coma, neovascular glaucoma, uveitic          cession glaucoma correlates with the
performed, asymmetry of the angle re-        glaucoma, lens-particle glaucoma and         extent and severity of angle recession.
cess may be noticeable between the af-       phacolytic glaucoma.                            In general, angle-recession glau-

42       o c t o b e r   2 0 1 0
                             coma is more difficult to control medi-
                                                                                 From clerical staff to
                             cally and surgically than other types
                             of glaucomas. Because angle-recession               ophthalmic surgical nurses
                             glaucoma can occur even many years
                             after trauma, patients should receive               Allied health staff members are a critical
                             adequate counseling, and follow-up                  part of your practice’s patient care team.
                             examinations should be performed
                             regularly.

                             1 Tesluk, G. C. and G. L. Spaeth. Ophthal-
                             mology 1985;92:904–911.
                             2 Mermoud, A. et al. Ophthalmology
                             1993;100:634–642.

                             Dr. Boonyaleephan is a visiting research schol-
                             ar in ophthalmology and Dr. Salim is associate
                             professor of ophthalmology; both are at the
                             University of Tennessee, Memphis.

                              6




                              7




                              8




                             COMPARISON. These eyes show angle
                             recession in a Caucasian (6) and two
                             African-American patients (7,8). The
                             widening of the ciliary body band has             Provide them with proper training resources to increase quality of care
                             different colors (beige in 6, and bluish
                                                                               and efficiency. This will become even more important in the near future
                             in 7 and 8). Recession can be subtle
                                                                               due to our nation’s aging population. To help, the Academy offers clinical
                             (7) or more pronounced (6,8).
                                                                               education materials for all members of your team. Print, DVD and online
                                                                               products are available.
                                     Coding in Chicago
                                                                               For more information or to order, visit
                               Attend Glaucoma Cod-
                                                                               www.aao.org/alliedhealth or call 415.561.8540.
                               ing, event code “213.” It
s a r w at s a l i m , m d




                               walks you through suc-
                               cessful glaucoma docu-
                               mentation and coding and takes place
                               Sunday, Oct. 17, from 2 to 3 p.m.



                                                                                                                                               e y e n e t   43

				
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