A 58-year-old Hispanic female presented to the emergency room with a chief complaint of a red right eye and associated foreign body sensation beginning one day earlier. She denied any recent illness, allergies or pain. 

Her medical history was significant for high cholesterol, for which she takes simvastatin 20mg and a multivitamin. She’s also smoked half a pack of cigarettes per day for 30 years, and her mother has wet age-related macular degeneration bilaterally. 

On examination, her vision acuity, with habitual correction, was 20/40-2 OD and 20/100+1 OS with no improvement with pinhole. Her confrontation visual fields were full-to-careful finger counting, and motility testing was normal. Intraocular pressure (IOP) was measured at 14mm Hg OD, 15mm Hg OS via Tonopen (Reichert). Her pupils were round and reactive to light with no afferent pupillary defect. The anterior segment exam was positive for 1+ follicles and papillae. There was no preauricular node and her corneas were clear. 

A dilated fundus exam shows changes (Figure 1). An OCT was also obtained and is available for review (Figure 2).

Fig. 1. Although our patient’s initial complaint was a red eye, can you identify any other pathology based on her fundus photographs?
Fig. 1. Although our patient’s initial complaint was a red eye, can you identify any other pathology based on her fundus photographs? Click images to enlarge.

Take the Retina Quiz

1. What do the fundus changes in the posterior pole of both eyes represent?
a. Laquer cracks.
b. Choroidal rupture.
c. Drusen and geographic atrophy.
d. Angioid streaks.

2. What best describes the fundus photo and OCT of the left eye?
a. Subretinal fluid and hemorrhage due to choroidal neovascularization. 
b. Intraretinal fluid and outer retinal atrophy due to AMD.
c. Atrophy and subretinal fluid associated with pathological myopia.
d. Choroidal rupture through the macula with associated subretinal fluid.

3. What is the correct diagnosis for this patient?
a. Ehler-Danlos syndromes.
b. Pseudoxanthoma elasticum.
c. Pathologic myopia.
d. AMD with choroidal neovascularization.

4. How should she be treated?
a. Observation.
b. Refer for intravitreal injection.
c. Refer for cardiac workup.
d. Refer for genetic testing.

For answers, see below.

Fig. 2. Can you identify our patient’s diagnosis based on the OCT images of our 58-year-old patient’s right (at top) and left eyes?
Fig. 2. Can you identify our patient’s diagnosis based on the OCT images of our 58-year-old patient’s right (at top) and left eyes? Click images to enlarge.

Diagnosis

Our patient was diagnosed with mild viral conjunctivitis and recommended to use artificial tears pallitively as needed. Of particular interest were the changes seen in the macula and posterior pole of both eyes. 

We saw obvious peripapillary atrophy surrounding each optic nerve as well as subtle radial cracks or defects in Bruch’s membrane extending linearly from the optic nerve in various directions. These cracks or defects in Bruch’s membrane represent angioid streaks. The streaks extend into the macula in both eyes. What’s more, subretinal hemorrhages were seen in both maculas, with obvious elevation and subretinal fluid in the left eye. Despite the hemorrhage in the right eye, the macula appeared flat. 

Based on these changes, we were certain our patient had developed choroidal neovascularization (CNV) in both eyes as a result of the angioid streaks. An OCT confirmed an active CNV in the left eye with subretinal fluid. The macula in the right eye was flat with disruption of the inner-outer segment junction and minimal cystic changes. On further questioning, our patient reported being followed by a retinal specialist in the community for CNV in both eyes and had multiple intravitreal injections in both eyes to control the bleeding. 

Discussion

Angioid streaks are typically bilateral and rarely seen outside of the posterior pole. They emanate from the optic nerve radially and taper as they get further from the optic disc. The angioid streaks appear as crack-like breaks in Bruch’s membrane and retinal pigment epithelium (RPE) atrophy. They can have varying colors depending on the tint of the fundus. In patients with a lighter fundus, the streaks will appear red, while those with a darker fundus will show medium to dark brown streaks.1,2 

Angioid streaks often have a systemic association.3 The most common are grouped into the mnemonic PEPSI:

  • Pseudoxanthoma elasticum (PXE)
  • Ehler-Danlos syndromes
  • Paget’s disease of the bone
  • Sickle cell disease and other hemoglobinopathies
  • Idiopathic causes

Interestingly, angioid streaks do have as high as 25% association with optic disc drusen.3

Systemically, many of these conditions associated with angioid streaks can be life-threatening. Pseudoxanthoma elasticum and Ehler-Danlos can have cardiac complications, whereas sickle cell anemia can cause organ failure or stroke due to clotting.2 Because of the seriousness of these conditions, it is important to recognize the clinical findings and refer these patients as indicated. 

The most common systemic association with angioid streaks is PXE, which is a hereditary disorder that affects the elastic tissues of the skin, eyes and blood vessels. Pseudoxanthoma elasticum usually affects the skin first, resulting in a classic “plucked-chicken” skin appearance on the lateral side of the neck, axillae and flexure creases. Eighty percent of clinical cases show mutations in the ABCC6 gene leading to abnormal MRP6 protein, which allows for genetic testing confirmation, if warranted.2 Patients with PXE often have a characteristic peau d’orange, or “orange peel” appearance to the retina and RPE.2 This dimpling of the RPE can be seen on the fundus photographs temporally in the right eye of our patient. 

Ehler-Danlos syndromes are a hereditary group of connective tissue disorders that result in hypermobility, skin hyperextensibility and tissue fragility. Individuals with Ehler-Danlos syndromes can develop several ocular complications such as keratoconus, high myopia, retinal detachment, lens dislocation and angioid streaks. 

Angioid streaks are typically asymptomatic, unless they involve the macula. Severe visual impairment is seen in 70% of cases with angioid streaks due to CNV.2 Researchers estimate that CNV occurs in 72% to 86% of all patients with angioid streaks, and becomes bilateral 50% of the time within 18 months of the initial CNV presentation.1,3 

OCT and fluorescein angiography are excellent ancillary tests to help assess the stability of the outer retina and any development of CNV as well as identify any breaks in Bruch’s membrane or RPE abnormalities. 

Upon further questioning, our patient revealed that she was diagnosed with PXE many years ago. The patient was initiated on a treatment plan of intravitreal injections of Avastin (bevacizumab, Genentech) in both eyes with re-assessment every four weeks with OCT to monitor the subretinal fluid and hemorrhages.

Dr. Dillinger is a resident at Bascom Palmer Eye Institute.

1. Lam L. Retina. Vol. 2. 5th Edition. Saunders; 2013:1267-73.
2. Ringpfeil F, Lebwohl MG, Christiano AM, Uitto J. Pseudoxanthoma elasticum: mutations in the mrp6 gene encoding a transmembrane atp-binding cassette (abc) transporter. Proc Natl Acad Sci USA. 2000;97(11):6001-6
3. Abusamak M, Abdelal O, Kharouf I, Hamdan S. Improving Differential Diagnosis of Angioid Streaks. Retinal Physician. www.retinalphysician.com/issues/2011/nov-dec/improving-differential-diagnosis-of-angioid-streak. Nov. 1 2011. Accessed Feb. 12, 2018.


Retina Quiz Answers:

1) d; 2) b; 3) b; 4) b.