Sullivan_EU_Ophthalmic_Layout 1 21/01/2010 12:13 Page 102
Posterior Segment Retina
Vitrectomy in Diabetic Retinopathy
Sheelah Antao
1
and Paul Sullivan
2
1. Specialist Registrar; 2. Consultant Ophthalmic Surgeon, Moorfields Eye Hospital, London
Abstract
Pars plana vitrectomy (PPV) is integral to the management of late complications in diabetic retinopathy. As a greater understanding of the
pathophysiology of diabetic eye disease has developed, so the role of PPV has evolved. This article reviews the current indications for PPV
in diabetes (vitreous haemorrhage, tractional retinal detachment and combined rhegmatogenous and tractional retinal detachment) and
the evidence for potential future applications, such as in diabetic macular oedema. The role of pharmacological adjuncts, such as anti-
vascular endothelial growth factor (VEGF) agents, to reduce intraocular complications, improve success rates and minimise post-operative
complications is examined. Drug-induced vitreolysis as a tool in achieving complete vitreoretinal separation, thus reducing progression of
diabetic retinopathy, is discussed. It has already become routine practice for endolaser photocoagulation to be employed during PPV and,
in the future, vitreolytic and antiproliferative agents may also be important as adjuncts to achieve good outcomes.
Keywords
Diabetic retinopathy, pars plana vitrectomy
Disclosure: The authors have no conflicts of interest to declare.
Received: 15 October 2009 Accepted: 27 November 2009
Correspondence: Paul Sullivan, Moorfields Eye Hospital, City Road, London EC1V 2PD, UK. E:
Paul.Sullivan@moorfields.nhs.uk
The first successful pars plana vitrectomy (PPV) was performed in released from ischaemic retina. These tend to proliferate from
1970 in an eye with vitreous haemorrhage secondary to diabetes- the vascular arcades along the inner surface of the retina or into the
related changes.
1
Since then, advances in instrumentation such as substance of the gel, using its collagen matrix as a scaffold. Traction
wide-angled viewing systems, smaller instruments, the use of heavy on vessels at the vitreoretinal interface following posterior vitreous
liquids and more sophisticated software have enabled the role of PPV detachment (PVD) causes rupture, resulting in haemorrhage into the
in diabetic eyes to evolve, and it is now integral to managing late gel or the subhyaloid space. Pan-retinal photocoagulation (PRP)
complications of diabetic eye disease. results in regression of new vessels and peri-vascular fibrosis, which
may anchor the vitreous. Continued tractional forces can disrupt
The indications for vitrectomy in the Early Treatment Diabetic these vessels, causing recurrent haemorrhage, so vitrectomy can still
Retinopathy Study (ETDRS)
2
in 1987, where 5.6% of all 3,711 enrolled be indicated in otherwise quiescent retinopathy. As well as directly
patients underwent vitrectomy, were either vitreous haemorrhage reducing vision, blood that persists in the vitreous or subhyaloid
(VH) or retinal detachment with or without VH. Today, PPV is used space may lose pigment over time, giving rise to ghost cells, which
for VH, tractional retinal detachment (TRD), combined tractional impede trabecular aqueous outflow and raise intraocular pressure.
rhegmatogenous retinal detachment (TRRD) and, in some cases, where
tractional abnormalities may contribute to diabetic macular oedema. In the Diabetic Retinopathy Vitrectomy Study (DRVS),
3
616 eyes with a
recent onset of severe VH of at least one month’s duration and VA of
Pars Plana Virectomy in Diabetic Eye Disease 5/200 and below were randomised to undergo either early vitrectomy
The ETDRS was the first large randomised, controlled trial looking at or deferral for one year. The percentage of eyes achieving VA of 10/15
vitrectomy as an intervention for proliferative diabetic retinopathy or better was significantly higher in the early vitrectomy group
(PDR). Of the 243 eyes undergoing vitrectomy, 47.5% achieved visual throughout the four-year follow-up period. The greatest benefit was in
acuity (VA) of 20/100 or better compared with only 6.2% pre- patients with type 1 diabetes of less than 20 years’ duration, where
operatively. Although today’s success rates are much higher, this there was a sustained significant visual advantage over the deferral
demonstrated a clear benefit of PPV in a previously blinding condition. group throughout the four years. However, there was also an
increased number of patients in all diabetic sub-groups who
Vitreous Haemorrhage developed no perception of light (NPL) vision in the early-treatment
Despite advances in the management of and screening for diabetes, group. This may reflect, at least in part, surgical complications
a significant proportion of patients develop severe ocular associated with earlier vitrectomy techniques and instrumentation.
complications, usually related to proliferative disease. VH originates An early improvement in vision to at least 10/50 in the early
from new blood vessels, which develop in response to growth factors vitrectomy group was shown in all diabetes types, suggesting that in
102 © TOUCH BRIEFINGS 2009
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116