Ординатура / Офтальмология / Учебные материалы / Color Atlas of Ophthalmology The Quick-Reference Manual for Diagnosis and Treatment

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Antiinflammatories

An in flam m ator y respon se result s w h en cells are dam aged by m icrobes, p hysical agen ts, or ch em ical agen t s an d can be ch aracterized by redn ess, pain , h eat , an d sw elling (Fig. 14.3).

Corticosteroids

Cor t icosteroids com m on ly u sed in oph th alm ic pract ice are sh ow n in Table 14.7, an d are divided in to su bt ypes (sh ort-act ing, in term ediate-act ing, an d long-act ing) based on th eir durat ion of act ion .

Fig . 14.3 Antiinflammatories are given to suppress inflammation in patients with uveitis.

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Table 14.7 To pical Corticosteroids

Periocular inject ion s are also u sed to deliver cor t icosteroids w h en in flam m a- tor y con dit ion s are u n respon sive to topical t reat m en ts. Th e m ain in dicat ion s for periocular inject ion s are t reat m en t of in term ediate or posterior uveit is an d cystoid m acu lar edem a. Th e cor t icosteroids t ypically u sed are m ethylpredn isolon e (Depo-Medrol), t riam cin olon e aceton ide (Ken alog-40), betam eth ason e (Celeston e Solusp an ), dexam eth ason e (Decadron Ph osph ate), or available gen eric equivalen ts as sh ow n in Table 14.8.

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Table 14.8 Injectable Co rticosteroids

Topical Nonsteroidal Antiinflammatory Drugs (NSAIDs)

Topical NSAIDs cu rren tly u sed in oph th alm ology are sh ow n in Table 14.9 an d can be classed as acet ic acids, propion ic acids, an d a prodrug ar ylacet ic acid .

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Drug Combinations (Corticosteroids/Antibiotics)

Th e com bin at ion t reat m en t s are m u lt iple-dose su spen sion s, solu t ion s, an d oin t- m en ts for topical applicat ion th at in clu de cor t icosteroids com bin ed w ith an t ibiotics su ch as gen tam icin , polym yxin B, n eom ycin , tobram ycin , an d sulfacetam ide. Th e various cor t icosteroid/an t ibiot ic com bin at ion s are sh ow n in Table 14.10.

Mydriatics and Cycloplegics

Mydriat ic an d cycloplegic agen ts h ave been used in th e pract ice of oph th alm ology sin ce th e m id -n in eteen th cen t u r y. Trade n am es, st rength s, an d dosages are sh ow n in Table 14.11.

Glaucoma

Medicat ion s can preven t vision loss due to glau com a by slow ing or preven t ing in t raocular pressu re (IOP)-related dam age to th e opt ic n er ve (Fig. 14.4). Th e m a- jorit y of glau com a agen ts w ere developed for th e m ore com m on , in sidiou s form of th e disease, prim ar y open -angle glau com a (POAG). IOP plays an im por tan t role in th e n europath ology of POAG. Prevalen ce an d in ciden ce of POAG in crease as IOP in creases. Th erefore, if pat ien t s w ith in creased IOP or sign s of opt ic n er ve dam age are star ted early on m edicat ion s th at decrease IOP, vision can often be preser ved in th e long term . Seven classes of glaucom a drugs are u sed; th e n am es, adm in ist ra- t ion , an d con cen t rat ion s are listed in Table 14.12.

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Fig . 14.4 Cupping of the disk in glaucoma.

Beta-Adrenergic Blocking Agents

Mechanism

A disru pt ion in th e physiological product ion of aqu eou s h u m or n at urally resu lts in flu ct u at ion s in IOP. Th e m ajor site of aqueou s h u m or produ ct ion is in th e ciliar y body an d is part ially con t rolled by β-adren ergic receptors. Act ivat ion of th ese receptors cau ses an in crease in th e product ion of aqu eous h u m or w ith in th e ciliar y body. A β-an tagon ist reduces th e form at ion of aqueous h um or result ing in a low er IOP.

Indications

Th is agen t is u sed as a first-lin e t reat m en t of POAG. Prim ar y angle closure glau - com a (PACG) is also an in dicat ion , bu t th e agen t s th at supp ress aqu eou s h um or for- m at ion m ay be less effect ive in th is form of glau com a becau se th e ciliar y body m ay be isch em ic, ren dering th e β-receptors n on fun ct ion al. Never th eless, β-an tagon ist s are st ill in dicated in PAC because of th e redu ct ion in IOP-en h an cing relaxat ion of th e an terior ch am ber angle.

Contraindications/Adverse Effects

Th e sam e β-adren ergic receptors in th e ciliar y body are fou n d in oth er organ s, an d system ic side effect s m ay in clu de decreased h ear t rate, d ecreased blood p ressu re, an d exacerbat ion of in t r in sic bron ch ial asth m a an d ch ron ic obst r u ct ive pu lm o- n ar y disease du e to bron ch osp asm . Th is topical m edicat ion sh ou ld be u sed w ith cau t ion in p at ien t s w ith cardiac or lu ng d isease. Bet a xolol is a cardioselect ive β-1- adren ergic an t agon ist develop ed to avoid t h e p u lm on ar y com p licat ion of t im olol, th e n on select ive classic top ical β-adren ergic an t agon ist . Th e select ive an t agon ist m ay be as effect ive in low er ing IOP as t h e n on select ive, bu t p u lm on ar y sid e effect s h ave occasion ally been n oted . Th erefore, becau se of th e severit y of p u lm o- n ar y com p licat ion s in th e u se of th is class of glau com a agen t , cau t ion sh ou ld be u sed w h en con sid ering th is dr ug in th e p at ien t w ith excessive im p air m en t of pu lm on ar y fu n ct ion . Also, t h e effect s of system ic m edicat ion s su ch as β-block- ers, d igit alis, an d reserp in e can be en h an ced w it h th e u se of top ical β-ad ren ergic an t agon ist s.

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Prostaglandin Analogues

Mechanism

Th e prostaglan din class of glau com a agen t s at tem pts to alter th e IOP by en h an cing th e outflow of aqu eou s h um or. Th e classic route of aqu eou s outflow is th rough th e t rabecu lar m esh w ork in to th e can al of Sch lem m . Th e prostaglan din s also take advan tage of a sup plem en tal rou te of aqueous outflow th rough th e uveoscleral path w ay by in creasing th e por t ion of aqu eou s th at th e path w ay n orm ally drain s.

Indications

Lat an oprost w as th e first syn th et ic prostaglan din an alogue th at form ed a n ew class of drugs developed specifically for glau com a. A single daily dose h as been sh ow n to be m ore effect ive in redu cing IOP th an t im olol 0.5%adm in istered t w ice daily, establish ing th e prost aglan din class as a first-lin e t reat m en t for POAG. Th e prostaglan din s are adm in istered topically on ly.

Contraindications/Adverse Effects

Th ere h ave been n o m ajor system ic toxic effects of topical prost aglan din an a- logue use in glaucom a th us far, bu t th ese drugs are w ell kn ow n for som e com m on , un iqu e ocu lar effect s. Pat ien t s frequen tly acqu ire perm an en t darken ing of th e iris, conju n ct ival hyperem ia, conju n ct ival flush ing, red eye, an d a hyper t rich osis of th e eyelash es th at rem its w h en th e m edicat ion is stopped . Th ere are rare adverse effects in cluding cystoid m acu lar edem a, dam age to th e blood –ret in al barrier, an d a periocu lar pigm en t at ion of cosm et ic con cern .

Carbonic Anhydrase Inhibitors

Mechanism

Like th e β-adren ergic blocking agen t s, th is class suppresses aqueou s h u m or produ ct ion . Th e m ech an ism involves decreasing th e form at ion an d secret ion of aqu e- ous at an in t racellu lar level. Carbon ic an hydrase in h ibitors (CAIs) are th e on ly class of glau com a m edicat ion s th at ut ilize a system ic route of deliver y th rough oral m edicat ion s. A topical form , dorzolam ide, is also available an d is m ore com m on ly used th an th e system ic form .

Indications

Oral CAIs are u sually used to su pplem en t various topical agen t s w h en IOP is n ot being adequ ately low ered . Becau se of th eir system ic effect s an d in abilit y to low er IOP in depen den tly, CAIs are usu ally n ot u sed as a first-lin e or sole prim ar y t reat- m en t of glau com a. A com bin at ion of dorzolam ide an d topical t im olol, a β-an t ago- n ist , is available (Cosopt).

Contraindications/Adverse Effects

Th e p ossible adverse effect s of th e system ic CAIs, acetazolam ide, m eth azolam ide, an d dich lorph en am ide, in clude paresth esias, an orexia, gast roin test in al dist u r- ban ces, h eadach es, altered taste an d sm ell, sodium an d p otassiu m deplet ion , a predisposit ion to form ren al calculi, an d rarely bon e m arrow sup pression . Th ese side effect s are p ossible w ith th e topical CAIs bu t h ave a m uch low er in ciden ce. With dorzolam ide an d brin zolam ide th e m ost com m on side effect is altered taste sen sat ion .