New unilateral scotoma in a young woman

Examination reveals multiple cream-colored lesions throughout the posterior pole bilaterally.

Issue: February 25, 2017

ByElias Reichel, MD

ByAdam T. Chin, MD

A 25-year-old woman was referred to the New England Eye Center by an outside ophthalmologist for evaluation of a new visual field deficit of the left eye. Approximately 1 week before presentation, the patient noticed an area of blurred vision in the temporal aspect of the left visual field. She felt that her central vision was spared and that the other eye was unaffected. She denied any other visual or neurologic symptoms.

With regards to ocular history, the patient sees an eye care provider yearly. She wears glasses and contacts for mild myopia (–2.5 D right eye, –2.25 D left eye) but otherwise has not had any eye issues or trauma.

The patient’s only chronic medical conditions are asthma and seasonal allergies for which she takes a daily oral antihistamine and occasionally uses an albuterol inhaler. Her surgical history includes adenoidectomy and placement of myringotomy tubes as a child. Otherwise, she describes herself as generally healthy, although she reported a recent cold. Her family history is unremarkable.

Examination

On examination, the patient was a healthy-appearing young woman. Her vision with correction was 20/20-1 in the right eye and 20/30+2 in the left eye. Pupils were equally round and reactive to light without an afferent pupillary defect in either eye. IOP was 14 mm Hg in both eyes. External exam was unremarkable, revealing normal lids and adnexa. Conjunctiva, sclera and corneas were quiet. Rare cells were present in both anterior chambers. Irides were normal. Lenses were clear.

On dilated fundus exam, there were rare white cells in the anterior vitreous bilaterally. Both optic nerves were pink with sharp borders and equal cup-to-disc ratios of 0.2. In the right macula, there were five cream-colored subretinal lesions throughout the posterior pole but sparing the fovea. Examination of the left eye revealed eight to nine similar lesions scattered through the posterior pole with several coalescing to involve the fovea (Figure 1).

Figure 1. Fundus photographs of both eyes. Right eye: The optic nerve appears pink with sharp borders and a cup-to-disc ratio of 0.2. In the right macula, there are five cream-colored choroidal lesions throughout the posterior pole but sparing the fovea (left). Left eye: The optic nerve appears pink with sharp borders and a cup-to-disc ratio of 0.2. In the left macula, there are eight to nine similar choroidal lesions scattered through the posterior pole with several coalescing to involve the fovea (right).

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Subretinal lesions

The differential diagnosis for multiple cream-colored subretinal lesions in the posterior pole must include the white dot syndromes. This phenotypic moniker refers to a group of inflammatory chorioretinopathies, which includes acute retinal pigment epitheliitis, multiple evanescent white dot syndrome, acute posterior multifocal placoid pigment epitheliopathy, multifocal choroiditis and panuveitis, acute zonal occult outer retinopathy, birdshot retinochoroidopathy and serpiginous choroidopathy. All of these syndromes present with white lesions in the posterior pole. Depending on the specific syndrome, they can represent discrete lesions of the choroid, choriocapillaris, retinal pigment epithelium or retina.

Other diagnoses that should be considered are diffuse unilateral subacute neuroretinitis, tuberculosis-associated serpiginous-like choroidopathy, relentless placoid retinochoroiditis, punctate inner choroidopathy and subretinal fibrosis syndrome. While the patient is otherwise healthy, a personal or family history of cancer would raise concern for choroidal metastases and lymphoma.

Workup and management

Before the patient’s visit at the New England Eye Center, Humphrey 10-2 visual field testing done by the outside ophthalmologist revealed a full central visual field in the right eye and a crescent-shaped scotoma involving the superior, temporal and inferior paracentral visual field in the left eye (Figure 2).

Figure 2. Humphrey visual field 10-2 of both eyes. Right eye: No scotoma (left). Left eye: Crescent-shaped scotoma involving superior, temporal and inferior paracentral visual field (right).

Figure 3. Fluorescein angiography of both eyes. Right eye (top): Early, intermediate and late show patches of early blocking and late staining that correspond to the locations of the lesions seen on exam. Left eye (bottom): Early, intermediate and late show a similar pattern of early blocking in the areas of the lesions that then stain in later frames.

Figure 4. ICG angiography of both eyes. In both right (top) and left (bottom) eyes, the lesions appeared hypointense during the early and late phases.

Figure 5. OCT of both eyes. Right: Horizontal line scan through fovea shows normal retina, retinal pigment epithelium and choroid (left). Left: Horizontal line scan through fovea shows disruption of the outer retina (from ellipsoid zone to outer plexiform layer) nasal to fovea and thickened choroid (right).

Fluorescein angiography revealed patches of early blocking and late staining corresponding to the locations of the lesions seen on clinical exam (Figure 3). The lesions were hypointense in both early and late phases on indocyanine green (ICG) (Figure 4). OCT through the right fovea revealed a normal retina, retinal pigment epithelium (RPE) and choroid. In the left eye, the outer retina (from ellipsoid zone to outer plexiform layer) of the nasal macula demonstrated hyperreflectivity and the choroid was thickened (Figure 5).

A workup for infectious etiologies revealed negative rapid plasma reagin, fluorescent treponemal antibody absorption and QuantiFERON Gold. Further labs including a complete blood count and basic metabolic panel were normal.

Discussion

Acute posterior multifocal placoid pigment epitheliopathy (APMPPE) is a rare inflammatory disorder of the choroid characterized by multiple white or cream-colored lesions of the macula. While there are no data specifically looking at the incidence of APMPPE, estimates of the incidence of white dot syndromes suggest that APMPPE affects less than 0.45 in 100,000 annually. Patients are most commonly young adults in their 20s to 30s. Unlike many of the other white dot syndromes, there is no apparent sex predilection.

As with the patient described above, approximately one-third of patients describe a preceding viral illness. However, the literature includes cases occurring after vaccinations and in association with numerous systemic infections and inflammatory conditions. Most commonly, patients present with bilateral macular lesions with varied degrees of vision loss depending on the exact locations of these lesions. In the patient presented here, she only noted a scotoma in the left eye, and the central vision in the right eye was spared despite bilateral lesions.

The primary mechanism of injury in APMPPE appears to be inflammation of the choriocapillaris leading to hypoperfusion and ischemia of the RPE and outer retina. The association between viral illness and APMPPE suggests an immunologic etiology. The genetic haplotypes HLA-B7 and HLA-DR2 are associated with APMPPE.

While a clinical diagnosis of APMPPE can be made by exam findings alone, multimodal imaging, especially those that provide information about the retinal and choroidal vasculature, is commonly used to confirm the diagnosis. On fluorescein angiography, the early phase is characterized by hypofluorescent patches, while late-phase imaging shows areas of staining, as seen in Figure 3. This early pattern is thought to represent nonperfusion of underlying choriocapillaris as well as possible blocking by subretinal pigment epithelial lesions. ICG similarly reveals choroidal nonperfusion, which appears as areas of hypofluorescence throughout the study (Figure 4). OCT through active lesions reveals hyperreflectivity of the outer retina. Enhanced depth OCT tends to show increased choroidal thickness. With autofluorescence imaging, placoid lesions of varying RPE hyperpigmentation and atrophy can be seen in the posterior pole. More recently, OCT angiography, which maps flow through the retina, choriocapillaris and choroid, has being used to characterize APMPPE. Multiple recent studies have directly demonstrated hypoperfusion of the choriocapillaris.

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The disease tends to be self-limited with resolution of lesions and visual symptoms over the course of 4 to 8 weeks. Twenty-five percent of patients end up with 20/50 vision or worse, with foveal involvement predicting poorer visual outcome. Therefore, some clinicians treat with systemic steroids, especially for foveal involvement, despite limited evidence of efficacy.

Due to the proximity of lesions to the fovea in the left eye of our patient, she was treated with a 7-day course of 60 mg of oral prednisone followed by a 2-week taper. One week after the initial presentation, she had subjective resolution of the right temporal scotoma, and her visual acuity improved to 20/25 in the right eye. At 3 weeks, her visual acuity had returned to 20/20. On exam, the lesions had resolved, leaving RPE hyperpigmentation.

References:
Crawford CM, et al. ISRN Inflamm. 2013;doi:10.1155/2013/783190.
Dolz-Marco R, et al. Retin Cases Brief Rep. 2017;doi:10.1097/ICB.0000000000000473.
Park SS, et al. JAMA Ophthalmol. 2016;doi:10.1001/jamaophthalmol.2016.1645.
Quillen DA, et al. Am J Ophthalmol. 2004;doi:10.1016/j.ajo.2004.01.053.

For more information:
Adam Chin, MD, and Elias Reichel, MD, can be reached at New England Eye Center, Tufts University School of Medicine, 750 Washington St., Box 450, Boston, MA 02111; website: www.neec.com.
Edited by Jessica Moon, MD, and Emily C. Wright, MD. They can be reached at the New England Eye Center, Tufts University School of Medicine, 750 Washington St., Box 450, Boston, MA 02111; website: www.neec.com.