Results of a Randomized Clinical Trial for Vitrectomy in Eyes
with Diabetic Macular Edema
Susanne Binder MD,
Ulrike Stolba MD, Ilse Krebs MD, Simon Brunner MD, Beatrix Neumaier,
MD
(Dept. of Ophthalmology, L. Boltzman Institute of Retinology and Biomicroscopic Laser Surgery Rudolf Foundation Clinic,
Vienna, Austria)
Background: Vitrectomy and peeling of the internal
limiting membrane (ILM) in eyes with chronic diabetic macular
edema has shown positive results in small retrospective studies.
In the present prospective study an expected number of 50 eyes is randomized
into two groups. In patients of group I a vitrectomy is performed,
group II serves as a control group. The 6 months results of first 34 eyes will be presented.
Method: In a prospective, randomized study the functional
and OCT outcome after vitrectomy (16 eyes in group I) is compared
with the results of control group (18 eyes in group II). During
surgery a pars plana vitrectomy with ICG staining and peeling of the
internal limiting membrane is performed. In patients older
than 65 the procedure is combined with a phacoemulsification of the
lens and posterior chamber lens(IOL) implantation.
Results: One month postoperatively in group I 69 %
of the eyes improved in visual acuity for far compared to 27 % in the control group II. Reading acuity was better after surgery
in 37 % in group I and in 16 % in group II
without operation. The OCT showed a reduction of the edema in 56 %
of the operated eyes in comparison to 16 % of the controlled
eyes. 3 months after surgery 56.5% of the eyes in group I
as against 22 % of the eyes in control group II had a better visual
acuity for far than initially. 37.5% in group I and 11 % in group II
respectively showed a better visual acuity for near. The edema
was reduced in 42 % of the eyes in group I and in only 5.5% in group
II compared
to preoperative values. 6 months postoperatively we found
50 % in group I and 22 % in group II with improved visual acuity for
far in comparison to the initial examination. 42 % of the
operated eyes in group I and 5.5% of the control eyes in group
II had a better reading acuity. The OCT measured a reduced edema in
56.5% (group I) and 22 % (group II) respectively in comparison
to the initial measurement.
Conclusion: Eyes with diabetic macular edema have
a 2 to 2.5 times higher chance for an improvement of the visual
acuity for far after vitrectomy compared to non-operated controls.
The visual acuity for near is better 2 to even 7 times more
often in eyes with surgery than without. The OCT measurements were
more related to the results for visual acuity for far and
showed a reduction of the edema with a higher likelihood of 2 to 3
times in vitrectomized eyes.