Radiation Maculopathy/Retinopathy (Grand Rounds)

From EyeWiki
Original article contributed by: Jesse L. Berry, MD
All contributors: Jesse L. Berry, MD
Assigned editor:
Review: Assigned status Up to Date by Jesse L. Berry, MD on June 8, 2017.


Rays Title.JPG

History

  • 66 year-old female presents for routine exam to monitor for tumor recurrence 20 months after brachytherapy
    • Choroidal melanoma OS s/p plaque brachytherapy
    • Choroidal nevus OD
  • Tumor has been decreasing in size on ultrasound
  • Last liver CT four months ago without evidence of metastatic disease
  • Reports occasional flashes in both eyes and slow decrease in vision OS

Exam Findings

  • VA 20/25; 20/100
  • Pupils RR OU, no RAPD
  • IOP 18; 14
  • EOM full OU
  • SLE unremarkable OU
Rays 1.jpg
Rays 2.jpg
Rays 3.jpg
Rays 4.jpg
Rays 5.jpg

Differential Diagnosis

  • VA 20/25; 20/100
  • Pupils RR OU, no RAPD
  • IOP 18; 14
  • EOM full OU
  • SLE unremarkable OU

Diagnosis

  • Radiation maculopathy/retinopathy

Pathophysiology

  • Exposure to radiation causes preferential loss of endothelial cells in the vasculature with sparing of pericytes. Irradiation causes direct endothelial cell damage as well as damage from free radicals created by radiation-related damage to red blood cells and iron.
  • Clinical findings:
    • Retinal microaneurysms (more prevalent in other vasculopathies, including diabetes mellitus)
    • Retinal hemorrhages
    • Retinal hard exudates
    • Macular edema
    • Cotton-wool spots
    • Retinal neovascularization
    • Vitreous hemorrhage
    • Tractional retinal detachment
    • Uveitis

Treatment

  • Intravitreal anti-VEGF
  • Intravitreal/periocular triamcinolone
  • Grid macular laser photocoagulation
  • Sector scatter and pan-retinal photocoagulation to areas of retinal non-perfusion
  • Photodynamic therapy, hyperbaric oxygen
  • Vitrectomy

Primary Prevention: Ways to decrease radiation dose or to treat before an issue is found

  • Shielding during external beam radiation
  • Hyperfractionationed external beam radiation
  • Collimating plaques
  • Prophylactic periocular triamcinolone
  • Prophylactic laser photocoagulation
  • Prophylactic anti-VEGF therapy

Prognosis and Future Directions

  • Radiation retinopathy and neuropathy is the leading cause of permanent and severe vision loss after radiation
  • Onset of symptoms start from six months to three years (reported from one month to 15 years)
  • Radiation maculopathy risk factors:
    • 45 Gy dose for plaque brachytherapy, 15 Gy for external beam
    • Single total dose of radiation
    • Tumor height (>4mm)
    • Location closer to optic disc
    • Diabetes, hypertension, simultaneous chemotherapy, pregnancy
  • Proliferative radiation retinopathy risk factors:
    • Location closer to optic disc
    • Diabetes, younger age
  • Recent studies on OCT angiography as an new sensitive imaging modality for radiation retinopathy
  • Therapy is multimodal with anti-VEGF and intravitreal steroid injections. Some centers are using these modalities as prophylactic therapy with promising results.

References

  • Stallard HB. Radiotherapy for malignant melanoma of the choroid. Br J Ophthalmol. 1966 Mar;50(3):147-155.
  • Flick JJ. Ocular lesions following the atomic bombing of Hiroshima and Nagasaki. Am J Ophthalmol. 1948 Feb;31(2):137-154.
  • Puusaari I, et al. Ocular complications after iodine brachytherapy for large uveal melanomas. Ophthalmology. 2004 Sep;111(9):1768-1777.
  • Archer DB, et al. Radiation retinopathy–clinical, histopathological, ultrastructural and experimental correlations. Eye (Lond). 1991;5(Pt 2):239-251.
  • Shields CL, et al. Plaque radiotherapy for uveal melanoma: long-term visual outcome in 1106 consecutive patients. Arch Ophthalmol. 2000 Sep;118(9):1219-28.
  • Monroe AT, et al. Preventing radiation retinopathy with hyperfractionation. Int J Radiat Oncol Biol Phys. 2005 Mar 1;61(3):856-864.
  • Shields CL, et al. Optical Coherence Tomography Angiography of the Macula after Plaque Radiotherapy of Choroidal Melanoma: Comparison of Irradiated Vs Non Irradiated Eyes in 65 Patients. Retina. 2016 Aug;36(8):1493-505.
  • Horgan N, et al. Periocular triamcinolone for prevention of macular edema after plaque radiotherapy of uveal melanoma: a randomized controlled trial. Ophthalmology. 2009 Jul;116(7):1383-1390.
  • Shah SU, et al. Intravitreal bevacizumab at 4-month intervals for prevention of macular edema after plaque radiotherapy of uveal melanoma. Ophthalmology. 2014 Jan;121(1):269-75.

Contact

  • Jesse Berry, MD, Assistant Professor of Clinical Ophthalmology and Associate Director of Ocular Oncology, jesse.berry@med.usc.edu
  • Ramon Lee, MD, PGY-2 Ophthalmology resident, ramon.lee@med.usc.edu