title: Assessment of 180° rotation of the choroid as a novel surgical treatment for age-related macular degeneration.
abstract: OBJECTIVE
  Our objective was to examine the feasibility of rotating choriocapillaris, Bruch's membrane (BM), and retinal pigment epithelium (RPE) through 180° on a vascular pedicle and to assess revascularization and tissue preservation postoperatively. Such an approach could be used in the treatment of age-related macular degeneration where there is focal disease at the macula with healthy tissues located peripherally.
  
  
  METHODS
  Successful surgery was performed in six rhesus macaque monkeys, which have a very similar choroidal blood supply to humans. After inducing a retinal detachment, the recurrent branch of the long posterior ciliary artery was used as a pedicle around which a graft stretching to the temporal equator was rotated. Retina was reattached over the rotated graft and eyes were followed up for up to 6 months with repeated angiography and optical coherence tomography (OCT). The morphology of retinal cells and BM were assessed by immunohistochemistry and electron microscopy.
  
  
  RESULTS
  Revascularization of the choroid was limited, with reestablishment of drainage to the vortex veins seen in only one case. There was a secondary loss of the RPE and outer retina evident on histological analysis three months after surgery. The underlying BM however remained intact.
  
  
  CONCLUSIONS
  Pedicled choroidal rotation surgery is technically feasible in vivo with intraoperative control of bleeding. However, lack of graft revascularization with the technique in its current form leads to neuroretinal and RPE tissue loss, and graft shrinkage. We found no evidence that rotational grafts are likely to improve the outcomes presently achieved with free graft techniques.
authors.affiliation: University College London Institute of Ophthalmology & Moorfields Eye Hospital National Institute for Health Research Biomedical Research Centre, London, UK.
authors.forename: Edward
authors.initials: E
authors.lastname: Lee
authors.forename: Mandeep S
authors.initials: MS
authors.lastname: Singh
authors.forename: Helen E
authors.initials: HE
authors.lastname: Jones
authors.forename: Bashir
authors.initials: B
authors.lastname: Ahmed
authors.forename: Ian M
authors.initials: IM
authors.lastname: Andolina
authors.forename: Jake T C
authors.initials: JT
authors.lastname: Clements
authors.forename: Vy
authors.initials: V
authors.lastname: Luong
authors.forename: Peter M
authors.initials: PM
authors.lastname: Munro
authors.forename: Martin P
authors.initials: MP
authors.lastname: Lawton
authors.forename: Kenneth L
authors.initials: KL
authors.lastname: Grieve
authors.forename: George W
authors.initials: GW
authors.lastname: Aylward
authors.forename: Adam M
authors.initials: AM
authors.lastname: Sillito
authors.forename: Robert E
authors.initials: RE
authors.lastname: MacLaren
mesh_terms: D000818:Animals; D016570:Bruch Membrane / Q000637:transplantation* / Q000648:ultrastructure; D002829:Choroid / Q000098:blood supply / Q000637:transplantation* / Q000648:ultrastructure; D019842:Ciliary Arteries / Q000502:physiology; D005240:Feasibility Studies; D005260:Female; D005451:Fluorescein Angiography; D005500:Follow-Up Studies; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D006083:Graft Occlusion, Vascular / Q000503:physiopathology; D007150:Immunohistochemistry; D008253:Macaca mulatta; D008268:Macular Degeneration / Q000503:physiopathology / Q000601:surgery*; D008855:Microscopy, Electron, Scanning; D013508:Ophthalmologic Surgical Procedures; D051571:Protein Kinase C-alpha / Q000378:metabolism; D055213:Retinal Pigment Epithelium / Q000637:transplantation* / Q000648:ultrastructure; D012399:Rotation; D041623:Tomography, Optical Coherence; D019745:cis-trans-Isomerases / Q000378:metabolism; D000099178:Retinoid Isomerohydrolase
chemical_list: D005904:Glial Fibrillary Acidic Protein; D051571:Protein Kinase C-alpha; D019745:cis-trans-Isomerases; D000099178:Retinoid Isomerohydrolase