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    VF Outcomes in the TVT Study

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    This month, News in Review highlights selected papers from the original papers sessions at AAO 2019. Each was chosen by the session chairs because it presents important news or illustrates a trend in the field. Only four subspecialties are included here; papers sessions will also be held in six other fields. For more information, see the Mobile Meeting Guide.

    In findings from the Tube Versus Trabeculectomy (TVT) Study, visual field (VF) outcomes appear to be comparable between the two treatment arms. “Similar rates of visual field pro­gression were observed after both tube shunt implantation and trabeculecto­my,” said Swarup Swaminathan, MD, at Bascom Palmer Eye Institute in Miami.

    Patients with a history of diabetes, elevated intraocular pressure (IOP), or worse VFs at baseline were at higher risk for VF progression, he added.

    Study overview. This multicenter randomized trial was designed to describe and compare VF outcomes in two groups of patients: Those who underwent tube shunt surgery with the 350-mm2 Baerveldt glaucoma implant and those who underwent trabeculec­tomy with mitomycin C (0.4 mg/mL for two minutes).

    The analysis involved 122 patients (122 eyes) with previous cataract and/or glaucoma surgery. Patients were evenly split between the two treatment groups.

    Evaluating VFs. Participants were examined at multiple time points for up to five years following surgery. Each examination included measure­ments of visual acuity (VA) and IOP. VF measurements were included if the false-positive rate was less than or equal to 20% and the false-negative rate was less than or equal to 35%. VFs were excluded if VA was less than or equal to 20/400, or if the patient lost 2 or more Snellen lines from baseline due to any etiology other than glaucoma. Longitu­dinal linear mixed-effects models with best linear unbiased predictions were applied to estimate rates of change in mean deviation (MD).

    Results. For this cohort analysis, a total of 436 VFs were evaluated, with an average of 3.6 VFs per eye. The rate of MD change was –0.60 dB/year in the tube group and –0.38 dB/year in the trabeculectomy group (p = 0.34). Although elevated IOP at baseline was identified as a risk factor for VF progression, there was no significant association between IOP control and VF progression.

    —Arthur Stone

    Visual Field Outcomes in the Tube Versus Trabeculectomy Study. Pre­sented during the glaucoma original papers session. When: Monday, Oct. 14, 2:00-5:15 p.m. Where: South 152. Access: Free.


    Relevant financial disclosures: Dr. Swaminathan —None.

    For full disclosures and the disclosure key, see below.

    Full Financial Disclosures

    Dr. Hamada None.

    Dr. Lin None.

    Ms. Shoshany None.

    Dr. Swaminathan None.

    Disclosure Category



    Consultant/Advisor C Consultant fee, paid advisory boards, or fees for attending a meeting.
    Employee E Employed by a commercial company.
    Speakers bureau L Lecture fees or honoraria, travel fees or reimbursements when speaking at the invitation of a commercial company.
    Equity owner O Equity ownership/stock options in publicly or privately traded firms, excluding mutual funds.
    Patents/Royalty P Patents and/or royalties for intellectual property.
    Grant support S Grant support or other financial support to the investigator from all sources, including research support from government agencies (e.g., NIH), foundations, device manufacturers, and/or pharmaceutical companies.


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