Case of the Month

Edited by Robert N. Johnson, MD

Figure 1: Wide-field color fundus photographs of her right eye.  Note the discrete chorioretinal scars nasal and inferior the the macula. Subtle punched-out chorioretinal lesions in the macula. At the edge of the whitish scars, a grayish change is noted suggestive of choroidal neovascularization (inset).

Case History:

A 39 year-old woman presents with blurred and distorted central vision in her right eye for a few weeks.  Her past medical history was remarkable for asthma and mild anemia.  Her past ocular history was remarkable for high myopia (~10D OU).  Her past family history, social history and medications were non-contributory.

On examination, best-corrected visual acuity was 20/25 and 20/16 in her right and left eye, respectively.  Intraocular pressure was normal in both eyes.  The anterior segment examination was unremarkable.  The posterior segment exam of the right eye was remarkable for several approximately 100-200um sized yellowish juxtafoveal chorioretinal lesions with some hyperpigmentation and mild retinal whitening (Figure 1 and inset).  No vitritis or hemorrhage was present on clinical exam, but the grayish appearance suggested choroidal neovascularization.  The posterior segment exam of the left eye was unremarkable.

Spectral domain OCT (SD-OCT) of the right eye revealed multiple focal ellipsoid disruptions (Figure 2) with hyperreflective lesions extending into the overlying retina but without a discrete linear extension as has been reported for the “pitchfork” sign consistent with inflammatory choroidal neovascularization (Figure 3, different patient).  One cut revealed a focal choroidal excavation (Figure 4) and an overall thin choroid.  Hyperreflective material was noted in the subretinal space.  OCT angiography (OCTA) of the right eye revealed choroidal neovascularization (Figure 5).  OCTA of the left eye was unremarkable.

Wide-field fundus autofluorescence (FAF) of the right eye revealed a few focal hypoautofluorescent lesions consistent with the atrophic white lesions on exam (Figure 6).  FAF of the left eye was unremarkable.

Figure 6: Wide-field fundus autofluorescence of the right eye is mostly unremarkable except for some mild reduced autofluorescence in the nasal macula.

Differential diagnosis

Presumed ocular histoplasmosis syndrome, tuberculosis, syphilis, West Nile virus, brucellosis, candidiasis, sarcoidosis, Blau syndrome, idiopathic multifocal choroiditis

Clinical Course

One month after she received an anti-VEGF injection in her right eye to treat the inflammatory choroidal neovascularization, her vision improved to 20/20 and her SD-OCT scan showed resolution of the subretinal hyperreflective material.  However, ellipsoid layer remained disrupted (Figure 7).  Two months after her second anti-VEGF injection, vision improved to 20/16 and her SD-OCT now showed partial recovery of her ellipsoid layer (fFigure 8).  After two anti-VEGF injections, OCTA of her right eye revealed persistent choroidal neovascularization however the network was smaller (Figure 9).  In addition, the posterior segment showed reduced retinal whitening and almost partial resolution of the grayish change around the chorioretinal scarring (Figure 10).

Discussion

Idiopathic multifocal choroiditis (MFC) is a progressive bilateral inflammatory disorder that usually affects healthy myopic Caucasian women.¹  Secondary causes of multifocal choroiditis can be due to infectious causes (such as presumed ocular histoplasmosis syndrome, tuberculosis, syphilis, West Nile virus) or inflammatory causes (such as sarcoidosis).

Patients often complain of metamorphopsia, temporal scotoma, floaters, photopsias and blurred vision.  On exam, the classic presentation are punched-out chorioretinal lesions ranging from 50 to 350 μm in the periphery and the macula.¹  There can be little to no uveitis in the eye or significant inflammation where the term MFC with panuveitis is used.  There is a high risk of secondary choroidal neovascularization (CNV) and subretinal fibrosis.  SD-OCT showing the presence of multiple, hyperreflective, vertical finger-like projections extending into the outer retina on OCT (so-called ‘pitch-fork sign, Figure 3, different patient) is felt to be consistent with inflammatory CNV.³  Other findings include peripapillary atrophy and pigmented curvilinear scars in the periphery (Figure 11, different patient).  These curvilinear scars were originally described in POHS and later termed ‘Schlaegel lines’. This finding is not specific for POHS and has been commonly used to describe this finding in patients with MFC as well.^4,5 On fluorescein angiography (FA), acute lesions of MFC will be hyperfluorescent and stain.  On indocyanine green angiography, several hypofluorescent spots are seen which may be more numerous than seen on FA or clinical exam.  On fundus autofluorescence, acute lesions will appear hyperautofluorescent while chronic lesions will appear hypoautofluorescent.

The principal sites involved in MFC are thought to be the sub-retinal pigment epithelium and outer retina.³ Acutely, there may be elevation of the RPE and ellipsoid abnormalities noted on SD-OCT evaluation.  With time, these may evolve to areas of atrophy.

Previously, punctate inner choroidopathy (PIC) and MFC were considered distinct diagnoses.  However, recently, it is mostly believed that they represent the same underlying disease entity.  Analysis of multimodal imaging indicates that there is little evidence to suggest classifying them separately and as the treatment algorithm is also the same, there is little utility in making that differentiation.⁶

In addition, MFC can present with an uncommon pattern of zonal, multizonal or diffuse outer retinal or chorioretinal atrophy (figure 12, different patient).⁷  To help differentiate this from acute zonal occult outer retinopathy, the typical trizonal degeneration is not demonstrated by multimodal imaging.

There is no universally accepted treatment algorithm for MFC in the absence of CNV.  Some suggest the start immunosuppression such as systemic corticosteroid for all MFC patients while others believe it should only be used when the lesions threaten central vision.⁸  If CNV is present, generally anti-vascular endothelial growth factor (VEGF) is recommended and can be done in conjunction with intraocular corticosteroids.  Photocoagulation of the CNV can also be considered.

References

1. Ryan S.  Retina, 5th ed.  2013:  1012-1025.
2. Hoang QV, Cunningham Jr ET, Sorenson JA, Freund KB. The “pitchfork sign” a distinctive optical coherence tomography finding in inflammatory choroidal neovascularization. Retina. 2013 May 1;33(5):1049-55.
3. Spaide RF, Goldberg N, Freund KB. Redefining multifocal choroiditis and panuveitis and punctate inner choroidopathy through multimodal imaging. Retina. 2013 Jul 1;33(7):1315-24.
4. Fountain JA, Schlaegel TF Jr. Linear Streaks of the equator in the presumed ocular histoplasmosis syndrome. Arch Ophthalmol 1981; 99:246-248.
5. Spaide RF, Yannuzzi LA, Freund KB. Linear streaks in multifocal choroiditis and panuveitis. Retina 1991; 11:229-231.
6. Spaide RF, Goldberg N, Freund KB. Redefining multifocal choroiditis and panuveitis and punctate inner choroidopathy through multimodal imaging. Retina. 2013 Jul 1;33(7):1315-24.
7. Jung JJ, Khan S, Mrejen S, Gallego-Pinazo R, Cunningham Jr ET, Freund KB, Jampol LM, Yannuzzi LA. Idiopathic multifocal choroiditis with outer retinal or chorioretinal atrophy. Retina. 2014 Jul 1;34(7):1439-50.
8. Tavallali A, Yannuzzi LA. Idiopathic multifocal choroiditis. Journal of Ophthalmic & Vision Research. 2016 Oct;11(4):429.