title: The Effects of 23-Gauge Pars Plana Vitrectomy on Orbital Circulation Using Doppler Ultrasonography in Diabetic Macular Edema with Epiretinal Membrane and Taut Posterior Hyaloid.
abstract: To evaluate using Doppler ultrasonography (DUS) how pars plana vitrectomy (PPV) affects orbital circulation in diffuse diabetic macular edema (DME) associated with either the epiretinal membrane (ERM) or taut posterior hyaloid (TPH).
  
  
  
  The sample included 46 eyes of 42 patients with DME associated with the ERM (n = 22, Group 1) or TPH (n = 24, Group 2). All participants received panretinal laser photocoagulation and antivascular endothelial growth factor injections preoperatively and underwent 23-gauge PPV combined with ERM or TPH removal and internal limiting membrane (ILM) peeling. Pre- and postoperative peak systolic velocity (PSV), end-diastolic velocity (EDV), and the resistivity index (RI) of the ophthalmic artery (OA), central retinal artery (CRA), posterior ciliary artery (PCA), and central retinal vein were measured with DUS.
  
  
  
  Statistically significant decreases in the PSV and EDV of the OA, CRA, and PCA were detected in all groups. In Group 1, the PSV of the OA and CRA as well as the EDV and PSV of the PCA declined significantly. In Group 2, the EDV of the OA and both the PSV and EDV of the CRA and PCA decreased. Postoperatively, the CRA's PSV and EDV were lower in Group 2, while the preoperative and postoperative RI of the CRA and preoperative RI of the PCA were greater in Group 2 than in Group 1. Changes in the CRA's RI, PSV, and EDV were greater in Group 2 after surgery.
  
  
  
  23-Gauge PPV combined with ERM or TPH removal and ILM peeling in DME reduces blood flow rates of both choroidal and retinal vessels. In eyes with TPH, the RIs of the CRA and PCA were significantly greater preoperatively and the changes in the CRA's RI, PSV, and EDV were greater postoperatively. The removal of the TPH may play a role in regulating blood flow.
authors.affiliation: a Istanbul Training and Research Hospital, EyeClinic , Istanbul , Turkey.
authors.forename: Hulya
authors.initials: H
authors.lastname: Gungel
authors.affiliation: b Beyoglu Eye Training and Research Hospital, Eye Clinic , Istanbul , Turkey.
authors.forename: Cigdem
authors.initials: C
authors.lastname: Altan
authors.affiliation: c Kudret Eye Hospital, Eye Clinic , Istanbul , Turkey.
authors.forename: Deniz Oygar
authors.initials: DO
authors.lastname: Baylancicek
authors.affiliation: d Istanbul Training and Research Hospital, Radiology Clinic , Istanbul , Turkey.
authors.forename: Yesim
authors.initials: Y
authors.lastname: Karagoz
authors.affiliation: d Istanbul Training and Research Hospital, Radiology Clinic , Istanbul , Turkey.
authors.forename: Tanju
authors.initials: T
authors.lastname: Kisbet
mesh_terms: D020533:Angiogenesis Inhibitors / Q000008:administration & dosage; D001775:Blood Circulation / Q000502:physiology*; D001783:Blood Flow Velocity; D001794:Blood Pressure / Q000502:physiology; D019842:Ciliary Arteries / Q000502:physiology; D003930:Diabetic Retinopathy / Q000503:physiopathology* / Q000601:surgery; D058450:Endotamponade; D019773:Epiretinal Membrane / Q000503:physiopathology* / Q000601:surgery; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D017075:Laser Coagulation; D008269:Macular Edema / Q000503:physiopathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009880:Ophthalmic Artery / Q000502:physiology; D009915:Orbit / Q000098:blood supply*; D012161:Retinal Artery / Q000502:physiology; D041623:Tomography, Optical Coherence; D018616:Ultrasonography, Doppler, Duplex; D014821:Vitrectomy
chemical_list: D020533:Angiogenesis Inhibitors; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human
keywords: 23-gauge pars plana vitrectomy; Diabetic macular edema; Doppler ultrasonography; epiretinal membrane; taut posterior hyaloid