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Pha colytic Gla ucoma

Th e pat ien t h as u n ilateral pain , defect ive vision , lacrim at ion , an d ph otoph obia. Open angles an d a hyperm at u re or m at u re cataract are seen along w ith in creased IOP, iridescen t par t icles, an d w h ite m aterial in th e an terior ch am ber an d on th e len s cap su le. Len s protein leaks from an in t act cataract an d obst ru ct s th e t rabecu - lar m esh w ork. In flam m at ion also con t ribu tes to th e glaucom a. Aging an d cataract form at ion are th e risk factors. Man agem en t con sists of redu ct ion of in flam m at ion an d IOP follow ed by cat aract ext ract ion .

Pha coa naphyla ctic Gla ucoma

Gran u lom atous in flam m at ion occu rs secon dar y to a hyp ersen sit ivit y react ion to len s par t icle released after pen et rat ing t raum a or su rger y.

Pha comorphic Gla ucoma

It is caused by an in t u m escen t len s leading to angle closure glau com a, secon dar y to eith er an en h an ced pup illar y block m ech an ism or du e to for w ard disp lacem en t of th e len s–iris diaph ragm .

Ectopia Lentis

Can also cau se an angle closu re glaucom a. Pu pillar y block m ay occu r due to th e len s being dislocated in to th e pu pil or an terior ch am ber or th e vit reou s h ern iat ing in to th e an terior ch am ber.

Uveitic Glaucoma

Inflam m ator y cells m echanically obstruct the trabecular m eshw ork (TBM) and are directly cytotoxic to the TBM. They cause a com bination of closed -angle glaucom a secondary to peripheral anterior synechiae (PAS), posterior synechiae, or total syn - echiae, form ation and OAG secondary to increased protein content of the aqueous, aqueous hypersecretion, obstruction by inflam m atory cells and debris, trabeculitis, scarring of the TBM, increased episcleral venous pressure, or as a steroid response.

Presentation

It is often u n ilateral, presen t ing w ith pain , ph otoph obia, redn ess, an d decreased vision . On exam in at ion , aqueous cells an d flare, open angles, irregular pu pil, posterior syn ech iae, PAS, in flam m ator y precip itates on th e p osterior corn eal su rface or t rabecular m esh w ork, ciliar y flu sh , an d oth er sign s of uveit is along w ith sign s of glaucom atou s dam age to th e eye m ay be seen .

Differential Diagnosis

Acute angle-closure glau com a, n eovascular glaucom a, Posn er-Sch lossm an syn - drom e, Fu ch s h eteroch rom ic iridocyclit is, steroid respon se glau com a

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Fig. 8.5 Uveitic evidence seen in an eye with increased intraocular pressure.

Management

Topical steroids an d cycloplegics are given for th e in flam m at ion , an d th e glaucom a is m an aged m edically (m iot ics an d p rostaglan din an alogues are n ot to be u sed becau se th ey m ay cau se a w orsen ing of th e in flam m at ion ) an d if requ ired su rgically w ith an t im et abolites or seton (Figs. 8.5 an d 8.6).

Elevated Episcleral Venous Pressure

Ven ous drain age obst ruct ion secon dar y to ret robu lbar t u m ors, thyroid eye disease, pseu dot u m or, cavern ou s sin u s th rom bosis, jugu lar vein obst ru ct ion , superior ven a cava obst ru ct ion , an d in t racran ial (St u rge-Weber syn drom e, carot icocavern ous fist u la, dural fist ula, ven ous varix) or orbital ar terioven ou s fist ulas can all lead to in creased episcleral ven ous pressu re. It can also in crease w ith ou t any obvious cau se.

Presentation

Th e pat ien t presen ts w ith a red eye. Th e ep iscleral vein s are gen erally dilated an d tort u ou s w ith a corkscrew appearan ce. Th e angles are open an d blood m ay be seen in th e Sch lem m can al.

Differential Diagnosis

Conju n ct ivit is, episclerit is, sclerit is, orbital in flam m at ion

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Fig . 8.6 Seton implantation procedure. A fornix-based conjunctival flap (C) is raised and the m ethylm ethacrylate baseplate (P) of the Seton is pushed under the conjunctival flap posteriorly and sutured to the scleral surface. The implant has a biconcave shape with the inferior surface shaped to fit the sclera. A small 3-mm -square half-thickness lamellar scleral flap (D) is raised just as in a trabeculectomy. An incision (F) is made into the anterior chamber under this scleral flap, and the long silicone tube (S) of the Seton is placed into the anterior chamber (the end of the silicone tube can be seen in the ante - rior chamber near the tip of the white arrow). Next, the scleral flap (D) is sutured down around the tube (S) of the Seton. Finally, the conjunctiva is sutured back in place. Aque - ous then drains from the anterior chamber (white arrow) down through the tube (S) to the baseplate (P) (black arrow), where a bleb forms. (Courtesy of Highlights of Ophthalmology,

“Innovations in the Glaucomas: Etiology, Diagnosis and Management,” English Edition, 2002. Eds: Benjamin F. Boyd, MD, FACS; Maurice H. Lunt z, MD, FACS; Co-Editor: Samuel Boyd, MD.)

Management

Approach to m an agem en t depen ds on th e cause. Filtering su rger y carries th e risk of in t raoperat ive ch oroidal effusion , exp ulsive h em orrh age, an d postoperat ive flat an terior ch am ber. Prophylact ic sclerotom ies in th e in ferior quadran t s sh ould be m ade prior to st art ing th e filtering su rger y. Th ese are left op en an d covered on ly w ith conju n ct iva at th e en d of surger y.

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Angle -Closure Glaucoma

Angle-closure glaucom a can be classified as angle-closu re glau com a w ith pupillar y block an d angle-closu re glaucom a w ith ou t pu pillar y block, each of w h ich can be fu r th er divided in to prim ar y an d secon dar y form s.

Acute Angle -Closure Glaucoma

Any in crease in th e n orm al con dit ion of relat ive pupillar y block because of th e cen t ral iris h ugging th e an terior len s surface causes th e periph eral iris to com e in con tact w ith th e t rabecu lar m esh w ork blocking th e aqu eou s outflow, causing an acute rise in pressu re.

Presentation

Th e pat ien t p resen t s w ith decreased vision , severe pain , redn ess, blu rred vision , colored h aloes aroun d ligh ts, n ausea, an d vom it ing. Circum corn eal congest ion , corn eal m icrocyst ic edem a, sh allow an terior ch am ber, m ild an terior ch am ber react ion , m id -dilated, vert ically oval pu pil, an d th e like are seen . In case of recurren t at t acks, posterior syn ech iae, periph eral an terior syn ech iae, glaukom flecken (sm all an terior su bcapsu lar len s op acit ies), sector or gen eralized iris at rophy, opt ic n er ve pallor an d cu pping, perm an en tly in creased IOP, an d visu al-field loss m ay be seen (Figs. 8.7 an d 8.8).

Fig . 8.7 Anterior segm ent optical coherence tomography in a patient showing narrow angles

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Fig . 8.8 Abraham’s argon laser iridectomy t wo-step technique—surgeon’s view of the second burn. The second burn is a penetrating burn aimed at the crest or peak of one of the iris humps (B), which resulted from the first burn. This second burn has now created a hole or iridectomy (D) through the peak of the iris hump (B). The first burn, which was partially penetrating, is shown in (A). Note the iris pigm ent drifting down while a gas bubble floats superiorly (arrow). Use the plano-convex but ton of the lens only for second

coagulation. (Courtesy of Highlights of Ophthalmology, “Innovations in the Glaucomas: Etiology, Diag - nosis and Management,” English Edition, 2002. Eds: Benjamin F. Boyd, MD, FACS; Maurice H. Lunt z, MD, FACS; Co-Editor: Samuel Boyd, MD.)

Management

Medical m an agem en t con sists of pilocarpin e, topical steroids, an t iglau com a m edicat ion s, pain killers, an d an t iem et ics. Th e defin it ive t reat m en t is laser iridotom y perform ed w ith eith er w ith an argon or YAG laser. In th e case of exten sive syn - ech iae w ith perm an en tly elevated IOP, a t rabecu lectom y m ay be required .

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Chronic Angle -Closure Glaucoma

Angle syn ech iae u sually begin superiorly an d progress in both direct ion s tow ard th e 6 o’clock p osit ion .

Presentation

Presen t at ion is sim ilar to prim ar y open -angle glau com a (POAG). Th e pat ien t h as in creased IOP th at is asym ptom at ic un t il dam age h as occurred . Diagn osis is by go- n ioscopy (Fig. 8.9).

Differential Diagnosis

Prim ar y or secon dar y OAG

Management

Medical m an agem en t an d laser iridotom y are used in early cases an d t rabecu lectom y in advan ced cases.

Neovascular Glaucoma

Secon dar y glau com a is caused by developm en t of n ew vessels in th e angle. Delayed diagn osis an d poor m an agem en t can cause loss of vision . Ret in al isch em ia or hypoxia an d subsequ en t release of angiogen ic factors cau ses n eovascular glau - com a. Elevat ion of IOP is due to fibrovascu lar m em bran es an d an terior syn ech iae blocking th e angle.

Presentation

Th e eye is pain fu l, ph otoph obic, an d red . Visu al acuit y m ay be as low as coun t ing fingers or n o p ercept ion of ligh t . IOP m ay be as h igh as 60 m m Hg. Conju n ct ival congest ion an d steam y corn ea are associated fin dings (Fig. 8.10).

A tiny early t uft of n ew vessels is visible first at the m argin of the pupillar y border. Th e vessels later en large to form knuckles. Th e pat ien t’s eye is exam ined under high

Fig . 8.9 Cupping of the disk.

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Fig . 8.10 Trabeculectomy with a fornix-based flap—removing the trabecular window— surgeon’s view. This is a surgeon’s view of the final incision to remove the trabecular window. It also reveals the surgeon’s view of the structures most important to proper trabeculectomy. The trabeculectomy flap, which is being excised, has been hinged backward exposing its deep surface to the surgeon’s view. The Vannas scissors (SC), make the final cut just in front of the scleral spur (S), on the trabecular tissue, which is here being reflected back with forceps (FP). The scleral spur is localized externally (E) by the junction of the white sclera and gray band (B). A, clear cornea; F, scleral flap; IR, iris

root; T, trabeculum . (Courtesy of Highlights of Ophthalmology, “Innovations in the Glaucomas: Etiology, Diagnosis and Management,” English Edition, 2002. Eds: Benjam in F. Boyd, MD, FACS; Maurice H. Lunt z, MD, FACS; Co-Editor: Samuel Boyd, MD.)

m agn ification . A sligh t pressure w ith th e gon ioscope or dilat ion of the pupil m ay obscure th e fin ding. Th e n ew vessels then appear on the surface of the iris to reach th e iris collaret te. Later n ew vessels extend from th e root of the iris to the ciliar y body and the scleral spur to arborize the t rabecular m eshw ork. Fibrovascular m em - bran es associated w ith neovascularization start cont racting to ten t the iris tow ard th e angle. Anterior synech iae an d iridocorneal adh esions are com m on fin dings.

Differential Diagnosis

Uveit ic glau com a, acute angle-closu re glau com a

Management

A th orough h istor y an d op h th alm ic an d ret in al exam in at ion s are m an dator y. Con - t rol of IOP an d in flam m at ion is th e first lin e of m an agem en t . Hyperosm ot ic agen t s an d m ydriat ic agen t s play an im por t an t role. Pan ret in al ph otocoagulat ion or periph eral cr yopexy m u st be perform ed at th e earliest oppor t un it y. Trabeculectom y w ith a sh u n t procedu re an d applicat ion of an t im et abolites is preferred . If th e IOP is ver y h igh an d th e pat ien t experien ces pain w ith n o usefu l vision , cyclodest ruct ive procedu res can be con sidered .

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Iridocorneal Endothelial Syndrome

Th is is a un ilateral con dit ion , seen m ain ly in w om en aged 30 to 50 years.

Presentation

Th e p at ien t u sually p resen t s w ith dim in ish ed vision an d pain . Th ere is m ovem en t of th e corn eal en doth elium on to th e iris. Loss of cells from th e corn ea w ou ld lead to corn eal sw elling, distor t ion of th e iris, m elt h oles, st retch h oles, an d a variable degree of distor t ion of th e pupil. Th e en doth eliu m becom es several layers th ick an d spreads over th e t rabecu lar m esh w ork, cau sing glau com a.

Th e slit-lam p exam in at ion reveals a “fin e h am m ered silver” ap pearan ce of th e corn eal en doth eliu m . Sp ecular m icroscopy dem on st rates pleom orp h ism in size an d sh ape w ith in cert ain cells an d a loss of clear h exagon al m argin s. Based on th e involvem en t of th e corn ea, th e disorder is called tot al, dissem in ated, or su btotal. Based on th e st ru ct u re involvem en t th e disorder is classified as follow s:

Ch an dler syn drom e, w h ich m ain ly involves th e corn ea

Cogan -Reese syn drom e, w h ich m ain ly involves th e angle, w ith a pigm en ted an d pedu n cu lated n odu le p resen t over th e iris

Progressive iris at rop hy

Differential Diagnosis

Ch an dler syn drom e, Cogan -Reese syn drom e, an terior ch am ber cleavage syn drom e, previou s ocu lar t rau m a, posterior polym orph ous dyst rophy

Management

Corn eal edem a is m an aged by low ering th e IOP, u se of hyper ton ic salin e an d soft ban dage con t act len ses, an d, fin ally, pen et rat ing keratoplast y. Glaucom a is best approach ed w ith m edical m an agem en t (aqueous suppressan ts), an d, fin ally, w ith t rabecu lectom y in th e late st ages. Im m u n otoxin s h ave been foun d to be effect ive.

Malignant Glaucoma

Malign an t glau com a m ay be seen in th e postsurgical period on discon t in uat ion of cycloplegics or on addit ion of m iot ics. Th ere is posterior m isdirect ion of th e aqueous, in to th e vit reou s w h ere it accu m ulates an d displaces th e vit reou s for w ard, push ing th e ciliar y processes, cr yst allin e len s, in t raocu lar im plan t , or an terior vitreou s face for w ard, cau sing secon dar y angle closu re.

Presentation

Th e pat ien t presen ts w ith pain , redn ess, ph otoph obia, an d defect ive vision along w ith h igh IOP; a flat or ver y sh allow an terior ch am ber in th e presen ce of a paten t; periph eral iridectom y an d in th e absen ce of a ch oroidal detach m en t .

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Differential Diagnosis

Pu pillar y block glau com a, w oun d leak, ch oroidal detach m en t , an d su prach oroidal h em orrh age

Management

If th ere is n o iridectom y or if it is n ot paten t , a PI is perform ed to r ule ou t pu pillar y block glau com a. Medical m an agem en t con sist s of topical at ropin e an d ph en - yleph rin e as w ell as an t iglau com a m edicat ion s to con t rol th e IOP. All m iot ics are stopped . Hyperosm ot ics are given to sh rin k th e vit reous. Surgical m an agem en t is often requ ired . In aph akic/pseudoph akic eyes, th e YAG laser m ay be u sed to p erform an an terior hyaloidotom y an d posterior capsulotom y. If th e pat ien t is ph akic, a vit rectom y m ay be required to rem ove th e t rapped aqu eous. A PI sh ould be perform ed in th e con t ralateral eye. All m iot ics sh ould be avoided in th e pat ien t .