The Effect of IVA for Preventing Postvitrectomy Hemorrhage in PDR
Condition: Proliferative Diabetic Retinopathy
MeSH terms: Retinal Diseases; Diabetic Retinopathy; Hemorrhage
Study type: Interventional

Summary: 
      Aflibercept, a recombinant fusion antibody that binds to all subtypes of VEGF and PlGF, has
      been shown to induce effective regression of retinal neovascularization secondary to PDR but
      there had been lack of a well-structured prospective study about adjunctive use of
      intravitreal injection of Aflibercept (IVA) to reduce postoperative VH in PPV for PDR. In
      this study, we aim to assess the effect of preoperative IVA on the incidence of postoperative
      VH after PPV for PDR.
    

Detailed description: 
      The enrolled eyes were randomly assigned according to the Central Randomization System with a
      ratio of 1∶1 to IVA group and control group. Patients in IVA group received an IVA (0.5
      mg/0.05 ml) injection before surgery (1 to 5 days before surgery); patients in control group
      did not receive IVA injection before vitrectomy. The preoperative IVA injection was performed
      following a standard protocol. All patients underwent 25-gauge transconjunctival sutureless
      vitrectomy using the 25-gauge trocar and cannula system under local or anesthesia. Procedures
      such as fibrovascular membrane dissection, endodiathermy, or endolaser photocoagulation were
      performed with 25-gauge instruments as required. Intraoperative bleeding was controlled by
      either endodiathermy or increasing the irrigation pressure. Patients were examined 1 week, 1
      month, 2 months, and 3 months after surgery if there were no postoperative events. If
      postoperative complications, including VH, occurred, patients were instructed to visit the
      clinic regardless of the visit schedule. At each visit, any events involving the study eye
      between the visit schedules were recorded accordingly. At each postoperative visit, slit-lamp
      biomicroscope, indirect ophthalmoscopy, and fundus photographs were performed. The primary
      outcome of this study was incidence of VH after vitrectomy.

      Postoperative VH was defined as a new episode of VH of grade 1 or above occurring later than
      3 days after primary surgery and was evaluated according to the Diabetic Retinopathy
      Vitrectomy Study grading system. Incidence of VH at week 1, month 1, month 2 and month 3 were
      recorded. In the case of gas-injected eye, complications were assessed in the region without
      the gas bubble.

      Preoperative, intraoperative, and postoperative data were collected for each patient.
      Preoperative data included age; sex; duration and status of diabetes mellitus (HbA1C); other
      systemic diseases such as hypertension and renal function (serum creatinine); and ophthalmic
      parameters including best-corrected visual acuity (BCVA), intraocular pressure (IOP), lens
      status, previous pan-retinal photocoagulation (PRP), and indication for surgery.
      Intraoperative data included phacoemulsification and intraocular lens (IOL) procedures, SF6
      or air tamponade, and the presence of fibrovascular proliferation and tractional retinal
      detachment. Postoperative data included BCVA at each visit and number of episodes of
      complications.
    

Intervention name(s): IVA injection before vitrectomy
Intervention type(s): Procedure
Intervention description(s): Patients in IVA group received an IVA (0.5 mg/0.05 ml) injection before surgery (1 to 5 days before surgery)
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Other
Keywords: Proliferative diabetic retinopathy; vitrectomy; Aflibercept; intravitreal injection; postvitrectomy hemorrhage