title: ROP surgery and ocular circulation.
abstract: OBJECTIVE
  Visual results following vitreoretinal surgery for stages 4 and 5 retinopathy of prematurity are often disappointing, even when anatomic results are good. This poses the question whether the surgery or the post-operative care causes the optic atrophy. A hypothesis is proposed that ocular perfusion pressure (mean blood pressure minus intraocular pressure) during or after surgery may be too low to provide adequate ocular blood flow.
  
  
  METHODS
  This report analyses the published results of retinopathy of prematurity surgery, the techniques used, as well as data about blood pressure and intraocular pressure in premature infants.
  
  
  RESULTS
  Mean blood pressure in conscious premature infants is low and labile; it falls further under anaesthesia. Pre-operative intraocular pressure in retinopathy of prematurity patients is unknown, but intraocular pressure during vitrectomy is elevated, and likely elevated postoperatively.
  
  
  CONCLUSIONS
  Conditions during and after vitreoretinal surgery for retinopathy of prematurity are conducive to low ocular perfusion pressure and consequent ischaemia of the retina and optic nerve, which can contribute to poor visual results. Improved monitoring and control of ocular perfusion pressure is warranted.
authors: Department of Ophthalmology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA.
authors: W A J
authors: WA
authors: van Heuven
authors: J W
authors: JW
authors: Kiel
mesh_terms: D001794:Blood Pressure / Q000502:physiology; D002829:Choroid / Q000098:blood supply*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D009896:Optic Atrophy / Q000209:etiology*; D011182:Postoperative Care / Q000009:adverse effects; D012039:Regional Blood Flow; D012163:Retinal Detachment / Q000209:etiology / Q000503:physiopathology / Q000601:surgery*; D012178:Retinopathy of Prematurity / Q000503:physiopathology / Q000601:surgery*; D012591:Scleral Buckling / Q000379:methods; D014792:Visual Acuity / Q000502:physiology; D014821:Vitrectomy / Q000009:adverse effects* / Q000379:methods