White dot syndromes Flashcards
• Core 5 white dot syndromes according to BCSC retina:
(note uveitis book has a nice table around page 141.) In order (approximately) of best prognosis to worst prognosis—MEWDS, acute posterior multifocal placoid pigment epitheliopathy (placoid), birdshot chorioretinopathy, multifocal choroiditis/punctate inner choroiditis, serpiginous
• White dot syndromes (generally)
are inflammatory chorioretinopathies of unknown etiologies that are supposed to have white dots at some point in their presentation, although they don’t have to have it throughout the whole course. All bilateral except MEWDs. Usually no systemic manifestations except for APMPPE. Usually less likely to cause CME except birdshot more likely to have CME. Most rarely cause CNV except for PIC/MCP spectrum where CNV is common. All typically youngish except for birdshot (older) and serpginous (second older). All can have vitreitis except PIC. Female prevalence in all except APMPPE and serpiginous.
• MEWDS
multiple evanescent white dot syndrome, best prognosis of the white dot syndromes, affects women more than men and tends to affect young myopic white women. Usually presents with photopsias and decreased vision, often also with enlarged blind spot. Sometimes (half the time) viral prodrome as well. Generally unilateral; can have an RAPD.
Wreathlike hyperfluourescence on FA with staining of the lesions and of the optic nerve. Self-limited. What will persist on OCT are abnormal reflectivity of IS/OS junction.
• Acute posterior multifocal placoid pigment epitheliopathy
larger plaque-like lesions that are creamier in appearance and often 1-2 disc diameters in size. Often significant systemic associations, including cerebral vasculitis, thyroiditis, erythema nodosum and enteritis. Early blocking and late window defects on FA. There is a continuum of exam findings from APMPPE to serpiginous so there is a new term called “ampiginous” kind of a continuum between the two.
• Birdshot chorioretinopathy
also called vitiliginous chorioretinitis. Affects Caucasians that are A29 positive. If someone appears to have birdshot and is not Caucasian or is not A29 positive, you should rethink your diagnosis. Occurs in 40s-70s age range typically, whereas the others present in younger patients. Think about Dick Cheney about to pop up and shoot you in the face. Tend to have more perifoveal leakage and cystoid macular edema. Specific buzzword on FA is “quenching”, where the dye appears to leave the circulation very quickly. Appears to happen because the vessels are slightly leaky. The lesions on FA are hypo fluorescent especially early in the FA and then in the late phase of FA there is diffuse hyper fluorescence.
• Punctate Inner Choroidopathy to Multifocal Choroiditis/panuveitis
really a spectrum from PIC—no uveitis with white dots that eventually scar over and appear as punched out atrophic lesions, all the way to multifocal choroiditis with panuveitis. On FA the lesions will initially stain but eventually become window defects. High rate of CNV (30-40%) eventually. Spectrum of inflammation with PIC with no inflammation to MFC with panuveitis.
• Serpiginous chorioretinopathy
snake like lesions starting from the optic nerve that lead to geographic scars with active edges that stain. Can have associated vasculitis. Disease that commonly recurs.
• AZOOR
acute zonal occult outer retinopathy. Not technically a white dot syndrome Many similarities to MEWDs. Tends to happen in young myopic women, present with photopsias, enlarged blindspot. Tend to have more nasal field loss and tend to be bilateral whereas MEWDS is unilateral. Typically larger visual field defects, and over areas of RPE atrophy/depigmentation. Defining symptom is photopsias.
• Acute Macular Neuroretinopathy (AMN)
Not technically a white dot syndrome. Affects women a little bit more often than men. Unique in that the patient will be able to describe a wedge or tear-dropped shaped scotoma. Get them to draw it out on an Amsler. When you look at their macula you may even see a lesion corresponding to the shape they drew (it can take a couple of weeks to appear). Can be seen on the en face image of the OCT Mac. Pathophysiology thought to be ischemia to inner nuclear layer or outer nuclear layer—near the “watershed zone” of the retina which is the OPL.
• Acute idiopathic maculopathy (AIM)
you get spontaneous exudative retinal detachment—spontaneous subretinal fluid. Typically complete vision recovery without intervention but leaves behind a bullseye maculopathy.
• Vogt-Koyanagi-Harada disease (VKH)
affects melanocytes. Can affect skin as well as melanocytes in the inner ear, which is why people can get tinnitus and dysacusis. Does not usually occur in patients of European or African descent. More typically in Japanese populations, but also American Indians, middle east, asia. Basically not Europe or Africa. Three phases—prodromal, then acute uveitic, and the chronic convalescent stage.
3-4 phases of VKH in detail
o Phase 1 of VKH: prodromal phase, viral-like illness, can get tinnitus, dysacusis and meningitis—can look a lot like viral meningitis; bad headache with a flue
o Phase 2 of VKH: Acute uveitic phase—where the majority of the ocular symptoms start. Affects the RPE and the choroid so you can get panuveitis, a serous retinal detachment (shifting fluid if you lean them in different ways) thought to be due to inflammation at the level of the RPE. Can be painful, light sensitive. Can get Dalen Fuchs nodules, which are yellow-white lesions that develop between Bruch’s and RPE. Happens due to destruction of melanocytes with accumulation if inflammatory debris between Fuchs and RPE. Do not confuse with Forster Fuchs spots which are little bits of CNV occurring in myopic degeneration.
o Phase 3 of VKH: Chronic convalescent phase. The serous RDs and uveitis tends to improve and the depigmentation (involving the eye and other areas of the body) becomes more prominent. Can get skin blanching, alopecia, vitiligo, poliosis (patch of white hair), depigmentation of eyelashes, Sugiura’s Sign (hypopigmentation of limbus). You can also get depigmentation of the TM. You can get a pale disc with a sunset glow fundus.
o Phase 4(ish) of VKH: Chronic recurrent phase. Compared to the acute phase, it is usually granulomatous acute anterior uveitis as opposed to posterior inflammation.
• Sympathetic Ophthalmia
The eye is immunologically privileged; and when something disrupts that (like penetrating trauma), the immune system is exposed to ocular antigens. Also targets melanin-bearing cells. Can give you the panuveitis, from AC cell to posterior and intermediate uveitis and can also get serous retinal detachments. Can also get Dalen Fuchs nodules (yellow-white lesions that develop between Bruch’s and RPE). Extraocular manifestations like vitiligo and poliosis can also occur but much less frequently compared to VKH.
• Risk of Sympathetic ophthalmia after injury or surgery
May be a good idea to enucleate an eye that has no visual potential after penetrating trauma within around 1 week. The risk of sympathetic ophthalmia after penetrating trauma is actually 0.2-0.5% incidence. SO can happen after eye surgery as well, incidence is 0.01%. Has to do with uvea coming into contact with the conjunctiva, exposing the material to the lymphatic system of the conjunctiva.
