Ординатура / Офтальмология / Учебные материалы / Color Atlas of Ophthalmology The Quick-Reference Manual for Diagnosis and Treatment
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Fig . 5.14 Reis-Bücklers dystrophy.
Differential Diagnosis
Meesm an n dyst rophy, EBMD, gran u lar dyst rophy
Management
In it ial t reat m en t is directed at recu rren t corn eal erosion t reat m en t as w ith EBMD. Surgical p rocedu res m ay in clude lam ellar keratoplast y, pen et rat ing keratoplast y, or ph ototh erapeut ic keratectom y. Recu rren ce is com m on w ith p en et rat ing keratoplast y.
Stromal Corneal Dystrophies
Granular Dystrophy
Gran u lar dyst rophy is a com m on bilateral au tosom al dom in an t st rom al dyst rophy lin ked to a m ut at ion in th e BIGH3 gen e on ch rom osom e 5q31. St rom al deposits con sist of hyalin e, w h ich can be h igh ligh ted w ith Masson t rich rom e stain on cor- n eal h istopath ology. Several form s of th is dyst rophy exist .
Presentation
Sym ptom s t ypically occur as a result of recurren t erosion s an d m ay in clude blu rred vision , pain , foreign body sen sat ion , ph otoph obia, an d tearing. Exam in at ion sh ow s bread crum b –like op acit ies, t yp ically in th e cen t ral por t ion of th e an terior st rom a, w ith sparing of th e lim bu s (Fig. 5.15).
Differential Diagnosis
Avellin o dyst rophy, m acular dyst rophy
Management
Treat m en t is directed at recurren t erosion s. Ph ototh erapeu t ic keratectom y, lam ellar keratoplast y, an d pen et rat ing keratoplast y can be u sed for t reat m en t . Keratoplast y h as a good progn osis in cases w ith poor vision , bu t recu rren ce is possible.
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Fig. 5.15 Granular corneal dystrophy.
Lattice Dystrophy
Th is is a bilateral autosom al dom in an t st rom al dyst rophy lin ked to a m u t at ion in th e BIGH3 gen e on ch rom osom e 5q31. St rom al deposits con sist of am yloid, w h ich can be h igh ligh ted on corn eal h istopath ology w ith Congo-red stain . Several t ypes of th is dyst rophy exist , in clu ding an au tosom al recessive form .
Presentation
Pat ien ts are asym ptom at ic un less recurren t erosion s develop . Decreased vision can resu lt from deposit s. Exam in at ion reveals cen t ral refract ile bran ch ing lin es w ith in th e an terior corn eal st rom a th at are best seen on ret roillu m in at ion . Th e lim bus is spared (Fig. 5.16A,B).
A B
Fig. 5.16 (A) Lat tice corneal dystrophy. (B) Lat tice corneal dystrophy on retroillumination. (Both im ages courtesy of Mark J. Mannis, MD)
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Differential Diagnosis
En larged corn eal n er ves, gh ost vessels of in terst it ial kerat it is
Management
No m an agem en t is required if th e p at ien t is asym ptom at ic. Treat recurren t erosion s as described in sect ion on Recu rren t Erosion s (p . 156). Recurren ce is com - m on despite corn eal t ran sp lan tat ion , bu t th e procedure can be ben eficial in som e pat ien t s w ith a good long-term progn osis.
Macular Dystrophy
Macu lar dyst rophy is a rare bilateral au tosom al recessive corn eal dyst rophy w ith m u copolysacch aride deposit ion in any or all p or t ion s of th e st rom a. Alcian blue stain can detect th e dep osits on corn eal h istopath ology.
Presentation
Th ere m ay be recu rren t erosion sym ptom s. Decreased vision can occu r early in th e cou rse. Exam in at ion sh ow s gray-w h ite opacit ies w ith p oor m argin s, separated by in ter ven ing h aze or clou din ess w ith in th e st rom a. Lesion s often coalesce w ith t im e an d often involve th e en t ire corn ea, lim bu s to lim bu s (Fig. 5.17).
Differential Diagnosis
At ypical lat t ice or gran u lar dyst rophy
Management
Recurren t erosion sym ptom s can be t reated . Pen et rat ing keratoplast y or deep la- m ellar keratoplast y is often th e on ly surgical opt ion because of th e depth of st ro- m al opacit ies. Larger graft sizes m ay lim it recu rren ces.
Fig . 5.17 Early macular corneal dystrophy.
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Fig. 5.18 Central crystalline dystrophy of Schnyder. (Courtesy of Mark J. Mannis, MD)
Schnyder Corneal Dystrophy
Th is con dit ion is a bilateral, slow ly progressive autosom al dom in an t st rom al dys- t rop hy, w h ich is often referred to as Sch nyder cr ystallin e corn eal dyst rophy. It can be detected as early as 1 year of age w ith accum ulat ion of ch olesterol an d ph osph olipids w ith in th e st rom a secon dar y to abn orm al corn eal lipid m et abolism .
Presentation
Decreased vision is a presen t ing sym ptom . Exam in at ion sh ow s cen t ral corn eal opacificat ion w ith sparing of th e lim bu s. Th e epith elium rem ain s in tact w ith associated corn eal arcus developm en t in th e secon d or th ird decade of life. Su bepith elial cr ystals m ay be presen t along w ith m idperiph eral corn eal opacificat ion in som e cases (Fig. 5.18).
Differential Diagnosis
Oth er st rom al dyst roph ies, cen t ral corn eal scars, hyp erlip oprotein em ia
Management
Ch eck th e pat ien t’s fast ing lip id p rofile because 50% h ave elevated ch olesterol. If vision declin e progresses, pen et rat ing keratoplast y is w arran ted, w ith a p oten t ial for recurren ce.
Fleck Dystrophy
Fleck dyst rophy is an un com m on n onprogressive au tosom al dom in an t con dit ion th at begin s early in life. Affected keratocytes con tain t w o abn orm al subst an ces: glycosam in oglycan an d lipids.
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Presentation
Discrete, flat , gray-w h ite, dan dru ff-like opacit ies ap pear th rough out th e st rom a. Sym ptom s are m in im al, an d vision is n ot affected . Th e con dit ion m ay be associated w ith decreased corn eal sen sat ion , lim bal derm oid, keratocon u s, atopy, or pseudoxan th om a elast icum .
Differential Diagnosis
Posterior polym orph ou s dyst rophy, pre–Descem et dyst rophy, ich thyosis
Management
No t reat m en t is requ ired .
Central Cloudy Dystrophy of François
Th is is a bilateral sym m et rical st rom al dyst rophy th at is slow ly progressive an d au tosom al dom in an t . It can be associated w ith m egalocorn ea.
Presentation
Patients are asym ptom atic. Exam ination shows central corneal opacities w ith polygonal gray areas separated by intervening clear zones resem bling cracks. Haze extends into the anterior corneal strom a unlike w ith posterior crocodile shagreen (Fig. 5.19).
Differential Diagnosis
Posterior crocodile sh agreen , oth er st rom al dyst roph ies
Management
No t reat m en t is n ecessar y because vision is usu ally n ot redu ced .
Pre–Descemet Dystrophy
Th is is an acqu ired con dit ion .
Fig . 5.19 Central cloudy dystrophy of François.
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Presentation
Pat ien ts are gen erally asym ptom at ic bu t visu al acu it y can be affected . Sm all lin ear or pu n ctate gray-w h ite flecks are appreciated in th e deep st rom a. Th e con dit ion can be associated w ith keratocon us, posterior polym orph ous dyst rophy, an d epith elial basem en t m em bran e dyst rophy.
Differential Diagnosis
Fleck dyst rophy, posterior polym orph ou s dyst rophy, ich thyosis
Management
No t reat m en t is requ ired.
Posterior Amorphous Stromal Dystrophy
Th is is a rare, bilateral, slow ly progressive, au tosom al dom in an t con dit ion presen t- ing in ch ildh ood .
Presentation
Pat ien ts p resen t w ith diffu se, gray-w h ite lesion s in th e posterior st rom a, usu ally involving th e cen t ral area, bu t m ay involve up to th e lim bu s. Corn eal th in n ing w ith flat topography an d result ing hyperopia, cen t ral corn eal th in n ing, an d periph eral iris processes m ay be seen .
Management
Rigid gas perm eable con t act len ses are u sed to correct th e ast igm at ism . Visu al acu - it y is rarely affected .
Congenital Hereditary Stromal Dystrophy
Th is is an au tosom al dom in an t , bilateral, sym m et rical, n onprogressive st rom al dyst rop hy seen in th e n ew born .
Presentation
Cen t ral corn eal clou ding is seen in th e n ew born w ith sparing of th e periph eral st rom a. In fan t s develop am blyopia w ith nystagm u s an d squin t .
Differential Diagnosis
Congen it al h ereditar y en doth elial dyst rophy, congen it al glau com a, m ucopolysacch aridosis, bir th t rau m a, posterior polym orph ous corn eal dyst rophy
Management
Pen et rat ing keratoplast y is th e t reat m en t of ch oice.
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Posterior Corneal Dystrophies
Corneal Guttae
Th is is a focal accum u lat ion of collagen on th e posterior surface of th e Descem et m em bran e associated w ith en doth elial dysfun ct ion , corn eal clou ding, an d poten - t ial visu al loss.
Presentation
Th e lesion appears as a w art or excrescen ces in relat ion w ith th e en doth elial cells. Th e lesion s, called Hassall–Hen le bodies, ap pear at th e periph er y of th e corn ea an d are associated w ith aging. A “beaten m et al” appearan ce, visible during th e specu lar reflect ion , is associated w ith m elan in deposits.
Differential Diagnosis
Fu ch s en doth elial dyst rophy, Hassall-Hen le bodies
Management
Con sider specu lar m icroscopy. Han dling of th e corn ea m u st be gen tle during in t raocu lar surgeries becau se th is m ay h asten en doth elial com prom ise.
Fuchs Endothelial Dystrophy
Th is is a bilateral en doth elial dyst rophy result ing in progressive dam age to th e en - doth elium . It is rarely sym ptom at ic before 50 years of age. Reduct ion in th e n u m - ber an d fun ct ion of sodium an d pot assiu m aden osin e t riph osph at ase pum ps in th e en doth eliu m occu r, creat ing progressive corn eal edem a an d gut tae. Th e con dit ion is autosom al dom in an t or sporadic.
Presentation
Sym ptom s in clude decreased vision (w orse in th e m orn ing), foreign body sen sa- t ion , ph otoph obia, tearing, an d pain . Exam in at ion resu lts can var y from m ild guttae to severe m icrocyst ic an d st rom al edem a w ith bu llae form at ion . Th e Descem et m em bran e becom es th icken ed w ith an in crease in corn eal th ickn ess as fluid reten - t ion in creases w ith in th e corn eal st rom a. Su bepith elial fibrosis an d scarring m ay occur in later st ages (Fig. 5.20A,B,C).
Differential Diagnosis
Hassall-Hen le bodies, pseu doph akic or aph akic bullous keratopathy, Ch an dler syn - drom e, h erpes sim plex kerat it is
Management
Begin w ith su ppor t ive th erapy, in cluding art ificial tears an d in part icu lar sodium ch loride drops or oin t m en t . Hair dr yers can in crease fluid evaporat ion from th e corn ea if used carefu lly. Defin it ive surgical t reat m en t in clu des eith er a pen et rating keratoplast y or en doth elial keratoplast y (becom ing a preferred tech n iqu e w ith Fu ch s dyst rophy). Graft su r vival progn osis is good .
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A
B
C
Fig . 5.20 (A) Gut tae seen on retroillumination in Fuchs endothelial dystrophy. (B) Microcystic and strom al edema seen in Fuchs endothelial dystrophy. (C) Fuchs endothelial dystrophy with subepithelial bullae.
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Posterior Polymorphous Dystrophy
Th is t ype of dyst rophy is a bilateral en doth elial dyst rophy w ith gradu al progression . It m ay be au tosom al dom in an t or recessive an d h as been m apped to ch rom o- som e 20q11.
Presentation
Decreased vision an d pain m ay develop, bu t pat ien t s are often asym ptom at ic. Exam in at ion of th e posterior corn ea reveals grou ped vesicles, geograph ic gray lesion s, an d/or broad ban ds w ith scallop ed edges. Associated fin dings can in clu de corn eal edem a, h aze, corectopia, an d iridocorn eal adh esion s as w ell as glau com a. In fan t s m ay p resen t w ith cloudy corn eas (Fig. 5.21A,B).
Differential Diagnosis
Iridio-corneal endothelial syndrom e, congenital hereditary endothelial dystrophy, aphakic or pseudophakic bullous keratopathy, Fuchs dystrophy
Management
Pen et rat ing keratop last y is required for cases w ith sym ptom at ic decreased vision . Obser ve carefu lly for con curren t open -angle glau com a.
A
Fig . 5.21 (A) Edema and haze seen |
|
in posterior polymorphous dystro- |
|
phy. (B) Broad bands seen on slit illu- |
|
mination in posterior polymorphous |
B |
dystrophy. |
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Fig. 5.22 Diffuse epithelial and stromal edem a in child with congenital hereditary endothelial dystrophy.
Congenital Hereditary Endothelial Dystrophy
Th is is a bilateral corn eal dyst rophy w ith au tosom al dom in an t an d recessive form s. It cau ses en doth elial dysfu n ct ion .
Presentation
Sym ptom s in clu de bilateral clou dy corn eas an d diffuse epith elial an d st rom al edem a w ith a n orm al in t raocular p ressure an d th icken ed Descem et m em bran e. Th e recessive form p resen t s w ith bilateral corn eal edem a at birth w ith nystagm u s. Th is con dit ion appears w ith out ph otoph obia an d tearing, an d th ere is a lack of dys- t rophy progression . Th e dom in an t form is eviden t by age 2 w ith gradual progression of th e dyst rophy. Pain an d tearing are presen t in th e absen ce of ph otoph obia (Fig. 5.22).
Differential Diagnosis
Congen ital glau com a, m u copolysacch aridosis, congen it al h eredit ar y st rom al dys- t rop hy, posterior polym orph ou s corn eal dyst rophy, birth t raum a
Management
Topical sodium ch loride drops or oin t m en t s are h elpfu l. Pen et rat ing keratoplast y is used in cases w ith corn eal decom pen sat ion . Th ere is a con cern for am blyopia in in fan t s.
Ectatic Disorders
Keratoconus
Keratocon u s is a com m on bilateral, but often asym m et rical, disorder of corn eal th in n ing in w h ich th e cen t ral or in ferior paracen t ral corn ea un dergoes progressive th in n ing to t ake on th e sh ape of a con e. It begin s in adolescen ce an d progresses slow ly w ith st abilit y in late adu lth ood . A gen et ic predisp osit ion is suspected w ith gen e lin kages in cer t ain fam ilies, bu t eye ru bbing an d eye t rau m a rem ain a sig-