Neovascular glaucoma
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Transcript of Neovascular glaucoma
NEOVASCULAR GLAUCOMA
DR SIVATEJA CHALLA
Definition History Etiology Pathophysiology Clinical course Clinical features DD’S Investigations Treatment
DEFINITIONSevere form of secondary glaucoma characterised by fibro vascular
proliferation in the anterior chamber angle.
SYNONYMS1. Hemorrhagic glaucoma2. Thrombotic glaucoma3. Rubeotic glaucoma4. Congestive glaucoma
HISTORY 1906 Coats , NVI in CRVO termed as RUBEOSIS IRIDIS
1937 Kurtz , NVA leading to PAS formation
1963 Weiss et al, coined the term NEOVASCULAR GLAUCOMA
ETIOLOGYDiabetic retinopathy (M.C.C)
CRVO
Ocular ischemic disease
PATHOPHYSIOLOGYCHRONIC RETINAL ISCHAEMIA
ANGIOGENIC FACTORS RELEASED & DIFFUSED
NEOVASCULARISATION OF IRIS AND ANGLE
NEOVASCULAR GLAUCOMA
lens and vitreous acts as mechanical barriers and also releases vaso inhibitory
factors
So any complicated cat sx PCR,APHAKIA more predisposition
VEGF synthesised by all tissues in retina, mainly MULLERS CELL.
VEGF conc 50-100 times more in aqueous humour in NVG
STAGES PRE RUBEOSIS
PRE GLAUCOMA (RUBEOSIS IRIDIS )
OPEN ANGLE GLAUCOMA
ANGLE CLOSURE GLAUCOMA
Pre rubeosis stage1. In patients with predisposing risk factors such as DR, CRVO, etc it is important
to understand the risk of developing rubeosis irides and the chances for
progression to NVG.
2. Look carefully for NVI and NVA under high ,magnification
Pre glaucoma stage : rubeosis iridisa. NVI +/- NVA
b. IOP normal
c. Patients are asymptomatic
d. dilated tufts of preexisting capillaries and fine, randomly oriented vessels on the surface of the iris near the pupillary margin
Open angle glaucoma1. Elevated IOP
2. NVA and NVI increased
3. AC inflammatory reaction
4. Hyphema may be present
5. No PAS
6. Angles open
Fibro vascular fibrovascular membrane that covers the angle and anterior surface of the iris and may even extend onto the posterior iris
HALLMARK
Angle closure glaucoma Most patients are detected in this stage
PAS formation
Fibro vascular membrane contarcts leads to flat iris
Ectropion uveae present
IOP very high >60 mm hg
CLINICAL FEATURESSYMPTOMS
- Severe pain
- Headache ,vomiting
- Redness
- Watering
- Defective vision
- Photophobia
SIGNS- Reduced vision
- Ciliary injection
- Corneal oedema
- Deep AC with flare
- Hyphema
- Fixed dilated pupil
- NVI, NVA
- Raised IOP
Features Normal vessels New vessels
Location Iris stroma Pupillary marginsAngles
Arrangement Regular Irregualr
Appearance Tortuous Thin
Course Radial Arbourising
Character Not fenestrated Fenestrated
Scleral spur Not cross Crosses
Flouroscein No leakage leakage
DIFFERENTIAL DIAGONOSIS1. PACG no NVI and NVA
2. UVEITIC GLAUCOMA KP’S + ,Complicated cataract, band shaped keratopathy
3. FHI stellate KP’S, NVA+ ,NVI and NVG are rare
4. ICE syndrome corneal decompensation,correctopia,iris atrophy
5. Old trauma angle recession,iris pigment clumps, no NVI
6. Lens induced glaucoma
INVESTIGATIONS OCULAR : - Fundus Fluorescein Angiogram- to assess retinal ischaemia -Electroretinogram – to assess for retinal ischemia -Iris angiography- in cases of doubtful NVI, to confirm the diagnosis
-B scan ultrasound- if view of retina not SYSTEMIC : - BP, FBS PPBS, Carotid Doppler, lipid profile,renal profile
TREATMENTA. Identifying the underlying etiology and its timely and adequate treatment to
prevent the development and progression of NVG.
B. Once NVG develops and IOP is high, the major aspect of management is
control of high IOP to prevent optic nerve damage and continuous treatment
of underlying etiology.
Prophylactic treatment Pan retinal photocoagulation (PRP) DM In established cases of PDR, PRP +/- IVB done to prevent NVG
And even after PRP, close f/u is needed
CRVO PRP indicated only after 2 clock hours of NVA/NVI (CVOS)
OIS PRP indicated for cases with retinal ischemia on FFA
refer for neurological and cardiology assessment
Pan retinal photocoagulation
Make ischemic retina anoxic
Decreased angiognic factorDecreased new vessels
Reduces AS neo vascularisation
Goniophotocoagulationa. Adjunct to PRP
b. LASER therapy aimed at directly treating the NVA before development of NVG
c. No role once glaucoma is established
d. Low-energy argon laser treatments (0.2 seconds, 50-100 um, 100 - 200 mW) are applied to the neovascular tufts as they cross the scleral spur.
Management of glaucoma Medical management
Aqueous suppressants- beta blockers, carbonic anhydrase inhibitors, alpha agonists
Topical prostaglandin analogues can be tried though they may increase ocular inflammation
Miotics are contraindicated as they can increase inflammation and discomfort.
Frequent administration of are recommended to reduce inflammation that is inevitably
present topical steroids and cycloplegics .
Anti angiogenic drugs like bevacizumab intravitreal or intra cameral, reduces angiogenesis and
reduces inflammation
Management of glaucoma Surgical management :
1. Medical management with intra vitreal anti-VEGF along with retinal ablation
wherever possible may be sufficient to control the IOP in the open angle
stage of NVG
2. But in advanced stage with synechial angle closure surgical intervention for
IOP lowering is often required.
Surgical management Trabeculectomy Tube shunts Cycloablation
Trabeculectomy :a. Intraoperative use of anti-fibrotic agents is recommended to reduce the risk
of bleb failure due to subconjunctival scarring
b. The success rate of trabeculectomy with MMC in NVG at 1 year has been reported to be around 62.6% and reduced to 51.7% at 5 years *
c. With the use of preoperative Bevacizumab, success rate may improve up to 95%**
* Takihara Y, Inatani M, Fukushima M, Iwao K, Iwao M, Tanihara H. Trabeculectomy with mitomycin C for neovascular glaucoma: prognostic factors for surgical failure.Am J Ophthalmol 2009; 147:912–8.** Saito Y, Higashide T, Takeda H, Ohkubo S, Sugiyama K.Beneficial effects of preoperative intravitreal bevacizumab on trabeculectomy outcomes in neovascular glaucoma. Acta Ophthalmol 2010; 88:96–102.
Tube shunts
I. Glaucoma drainage devices are increasingly being considered as a primary
surgical procedure especially NVG where there is a high risk for failure of
conventional filtering surgery
II. Scarred conjunctiva, active inflammation, vigorous new vessel growth and
prior failure of trabeculectomy are also all indications to consider tube shunt
surgery in NVG.
Cycloablation : For refractive NVG, no PL eye to relieve pain,
◦ Cyclocryotherapy.◦ TSCPC, other contact and non contact trans scleral cyclo destructive procedures.◦ Endoscopic cyclo photocoagulation.
12-24 burn spots ,posterior to limbus over 360 degrees , 1500-2000 MW, 1.5-2 secs.
Treatment
NVG
Seeing eye NLP- Medical Rx - Cyclodestructive procedure
Clear media PRP
Poor media Cryoablation
Vitreous hge Vitrectomy+ endolaser
Trabeculectomy & Mitomycin
Tube shunts cyclophotocoagulation
Conclusionsa. NVG is a potentially blinding disease
b. Early diagnosis and aggressive control of high IOP and the underlying etiology is crucial to minimize the visual loss
c. Once IOP becomes elevated, successful management of disease becomes extremely difficult
d. No current medical or surgical treatment has a high success rate.
THANK YOU