1998 Abstracts

Principal of Laser treatment and when to refer a patient with Diabetic Retinopathy -  Subhadra Jalali Hyderabad

Laser treatment has revolutionized the treatment and prognosis of eyes with diabetic retinopathy. The judicious use this therapy can prevent significant visual loss in a significant number of eyes with diabetic retinopathy. The basic principles guiding the use and technique of laser treatment in eye with diabetic retinopathy has been provided by large multicentric clinical trials ie DRS and ETDRS.

Decision making and laser management protocols in patients with diabetic retinopathy

On the basis of various clinical trials, it is clear that early diagnosis and proper follow-up of patients along with good control of blood glucoses levels can reduce the indicate and severity loss from diabetic retinopathy. Below is a summary of the indications and treatment protocols of laser in such patients.

Photocoagulation in diabetic retinopathy

Indications for scatter treatment (PRP):

1)Full scatter treatment also know as panretinal photocoagulation (PRP) should be carried out promptly in all eyes with PDR having high risk characteristics ie (1) NVD more than or equal to ¼-1/3 disc area or (2) vitreous or pre-retinal haemorrhage with any amount of new vessels observed or assumed to be obscured by the haemorrhage.

2) whenever HRC are present, PRP should be carried out inspite pf presence of fibrous proliferation or TRD. Areas of fibrous proliferation and any tractional detachment should be avoided, and treatment should be mild to modrate as there is risk of extension of the localized TRD into the macula. A combination of vitrectomy and photocoagulation may be needed in some of these eyes.

3) Whenever iris or angle neovaularisation in seen, early PRP should be done irrespective of presence or absence of retinal HRC.

4) Consider PRP for eyes approaching HRC ie eyes with severe NPDR or eyes with PDR without HRC.

5) Eyes with severe ischaemia ie extensive retinal hemorrhages capillary non-perfusion multiple prominent soft exudates have risk of anterior segment neovascularisation and should be considered for PRP.

6) Eyes with burnt out retinopathy or showing regression of retinopathy should not be treated with laser. They can be kept under observation. Simlirly eyes with a single NVE without associated haemorrhage may be observed, provided patient comes for regular follow-up and has no other factors associated with worsening of retinopathy.

7) In eyes with PDR and maculopathy, macular treatment is preferably done first followed by PRP 2-4 weeks later.

8) If delay in PRP is undesirable, the focal macular treatment can be combined with nasal half PRP, followed 2-3 weeks later completion of PRP.

9) Various factor known to worse the retinopathy may influence the decision the to initiate treatment in eyes with severe NPDR or PDR without HRC . These factors include pregnancy, nephropathy, cardiac failure, carotid artery disorders, catract surgery and YAG laser capsulotomy, uncontrolled blood sugers, poor patient follow-up etc. it is better to initiate treatment early in these eyes rather than wait for HRC to develop, and this happens at a stage when patient needs dialysis or is in later stages of pregnancy these more pressing problems may interface with optimal treatment schedule in such patients. This is more true in our country where due to various social and economic factors cannot always come for regular follow-up or prompt treatment. The decision to treat or not to treat hence has to take into account all these factors, besides the guilines provided in the randomized clinical trials.

Follow-up treatment after initial PRP:

In about 25% eyes who undergo complete PRP for DRS –High risk characteristics, enough new vessels persist or recur to justify additional photocoagulation. The ETDRS guidelines for follow-up treatment after initial PRP includes consideration of six factors. These are :

change in new vessels since the last treatment /last visit.

Appearance of the new vessels (caliber, degree of network formation, extent of accompanying fibrous tissue) .

Frequency and extent of vitreous haemorrhage

Status of vitreous detachment

Extent of photocoagulation scars

Extent of tractional retinal detachment and fibrous proliferation.

Factors favouring additional photocoagulation:

Lack of registration within 6-8 weeks of the initial treatment.

Active new vessels (tight networks, little fibrous tissue, rapid growth in size)

Recurring vitreous haemorrhage, whether the source is visible or not.

Extensive intraretinal lesions( veous beading, IRMA bloat haemorrhage, retinal edema)

Skip areas and room for more burns in between previous scars.

Additional photocoagulation may be less urgent if:

The calibre of new vessels has decreased and fibrous proliferation is developing

There is a single episode of vitreous haemorrhage coincident with a posterior vitreous detachment and no recurrent hamorrhage thereafter.

There is extensive or almost complete posterior vitreous detachment.

If there is no space in between scars, and additional treatment will require confluent treatment clear indications are necessary before additional treatment is given as it can lead to exten field loss. In some cases vitrectomy maybe a better alternative.

If vitreous haemorrhage prevents additional photocoagulation, choice between vitrectomy with endophotocaogulation and observation is influenced more towards observation if :

Extensive scatter treatment has been applied

Intraretinal lesions are not active

Posterior vitreous has been detached from the macula and temporal vascular arcades

Past opthalmoscopy and present ultrasonogrphy does not show any traction on the macula

Blood is mostly behind the detached vitreous

Useful vision is present in the fellow eye.

If severe new vessels continue to proliferate inspite of extensive photocoagulation consider early surgery:

Indication for macular treatment:

Eyes with CSME with center involved should be considered for immediate laser treatment

Eyes with CSME without center involved and even with good vision, should also be considered for immediate laser treatment.

Eyes with macular edema which is not clinically significant should generally be watched without treatment

Promptness of referral

A major reason why patients with diabetes lose vision from retinopathy is that they do not receives proper ophthalmic treatment at the proper time. It is the responsibility of all physicians to make sure that all newly diagnosed NIDDM patients and all patients with IDDM of more than 5 years duration are examined at least yearly by an ophthalmologist. There is a high risk of diabetic retinopathy being present shortly after diagnosis of NIDDM. Many a times old patients do not report visual complements and so routine screening by the primary physician can help in early diagnosis. The best method of screening for diabetic retinopathy is still debated. Fundus photography general practitioners hospital physicians ophthalmic and trained optometrists have been advocated. The best method may involve one or more of these strategies depending on the envionment and cost-effectives. It is the responsibility of the ophthalmologist to be familiar with the criteria for photocoagulation and arrange for early referral, based on the guidelines given above.

Management Strategies for Eales Disease- Bijayananda patnaik New Delhi

Management of Eales disease can be highly satisfactory, only when its pathophysiology is understood . Eales disease is a clinical manifestation of retinal phlebitis leading to branch retinal vein occlusions usually multiple , predominantly peripheral and sometime central retinal vein occulusion. The severity and the course is highly variable. Acute vein occlusion may lead to spontaneous vitreous hameorrahage. More often vein occlusion leads to retinal ischaemia and proliferative retinopathy. This is the source of repeated vitreous haemorrahage in the majority of causes. On regression of new vessels with gliosis several serious complications may develop. Though the etiologies are not known, a selected group may be associated actual tubercular infection. The management consists of appropriate treatment at appropriate stages. Oral steroids and in selected cases antitubercular treatment during the stage of active phlebbits selective retinal ablation of the involved sector by scatter photocoagulation and sometimes antierior peripheral cryo and vitreous surgery in advanced cases or nonresolving vitreous hameorrhage gives excellent result contrary to what western literature predicit.

CRVO Diagnosis, when and how to treat - Dr. G.L.Verma

Diagnosis of CRVO had never been a problem for ophthalmologist but it has been difficult to predict which one would progress to develop ischaemic changes and complications of ocular neovascularisation in natural course of diseases. Controversy exists on prophylactic value of panretinal photocoagulation for neovascular glaucoma as only 60% of ischaemic CRVO develop INV and only 10-20% develop retinal neovascularisation. Longitudinal studies on ischaemic CRVO revealed that 1/3 cases of INV and ¼ cases of ANV never progress to NGV. The only dreaded complication is NVG which develops in approximately 30% case of ischaemic CRVO. The CRVO study group recommends panretinal photocoagulation after development of two clock hour iris /angle new vessels than before development of INV / ANV . Prophylactic PRP doesn’t prevent TC-INV/ANV but eyes with CNP>75DD sre at higer risk of developing TC-INV/ acuity in macular edema of CRVO. The macular edema can be managed on oral steroids. NVG can be followed closely up to one year. On each follow-up visit patient should have record of tonometry, undialated pupil gonioscopy, funds FA and IA. The TC-INV/ANV should be promptly treated with PRP. A non complaint patient with ischaemic CRVO features deserves PRP.

NEWER INDICATIONS FOR DIABETIC VITRETOMY & MANAGEMENT APPROACHES

Cyrus M.Shroff ,New Delhi

Goals of vitreous surgery for diabetic retinopathy are restore vision and stabilized the nonvascular process. The surgical objectives to achieve these goals are:

Removal of vitreous and pre-retinal blood

Reattachment of the macula

Removal of thickened posterior hyloid in the pre-macular area

Removal of vitreous scaffold & surface fibrovasular proliferation

Endophotocoaguation of ischemic retina

Eyes in which those surgical objectives are achieved and which have a good 6 months outcome tend to remain stable for many years the major indications for vitrectomy in diabetes are :-

Active proliferative diabetic retinopathy (PDR)

Dense premacular haemorrhage

Progressive macular traction

Diabetic macular edema with posterior hyaloid traction.

Retinopathy of prematurity(ROP)-Dr.M.R..Dogra ,Chandigarh

In India with development of neonatal intensive care units, premature with extremely low birth weight are surviving and at highest risk for ROP. Infants with more weight having history of prolonged oxygen administration are also included. The first examination is recommended between 4 to 6 weeks after birth. In avascular retina examination is done every two weeks. Prethreshold disease require weekly exmination till threshold disease develops or spontaneous starts. ROP regresses spontaneously in more than 80% of eyes with stage 1 and 2^nd disease

Cryotherapy or laser treatment with indirect laser delivery system recommended to entire avascular retina in threshold ROP. Laser is preferred over cryotherapy as it avoids general anesthesia and is easily performed at bed side even in zone I disease. Scleral buckling is required for stage 4 ROP . advanced vitreoretianl surgery is done for stage which has extremely poor visual results.

A rigid screening protocol and treatment of threshold ROP with crytherphy or laser is the most important key in management of ROP. Once ROP has reached advanced stage (stage4 and 5 ) it results in poor visual outcome despite advanced vitreoretinal procedure.

UNDERSTANDING AND MANAGEMENT OF CSR-Rajinder k. Patnaik New Delhi

A clinical of central serous retinopathy (CSR) is make when patient complete of a central scotoma or a reduced visual acuity and shows a blister like detachment of the macula. These on flourescein angiogrphy show dye leakage and are 2 types. Type I with single point leakage and are generally self limiting. One can abort the attack by mild photocoagulation. Type II are with multiple staining and leaking lesions, often bilateral, recurment and deteriorate with sustained oral corticosteroids. These seems to be cases of choroiditis with specific etiology. In our country the majority respond well to drugs for tuberculosis. Thus it is important to know the difference. Steroids sre suoerflous in type I case and harmful II. Therefore , should not be used in CSR.

Management Strategies for Wet ARMD-Dr. H.K.Tiwari, New Delhi

Wet ARMD is a condition reserved for choroidal neovacular membranes or even poorly or ill defined CNVM, diffuse subretinal ooze or, pigment epithelial detachments and occult CNVs.

Classic CNVM presents as a grayest membrane beneath the retina surrounded by a haemmorhagic ring & reveals hyperflourescence on FFA in early transit phases. Occult CNVM on the other hand usually show late leakage 1-2 min. following progressive injection the boundaries may be well demarcated or poorly outlined. In the later phase, the areas of irregular RPE elevation may staining. In terms of location CNVM’s may be divided into:

Extra foveal : 200-2500 u from fovea

Juxta foveal : 1-199 u from fovea

Sub foveal: beneath the fovea

The MPS study group has clearly shown the efficacy of laser treatment in extra foveal CNVM. With regard to juxta foveal & sub foveal CNVM, the study concluded that thought there is an initial fall of visual acuity, however at 2yr follow up the laser treated eyes did better. In the subforeal CNVM category, there was improved – reading speed, better vision and improved contrast sensitivity.

Diabetic Macular Edema-Amod Gupta and Vishali Gupta , Chandigarh

Diabetic maculopathy is the commonest cause of moderate visual loss in diabetic mellitus. The ETDRS group defined CSME as :

Retinal thickening at or within 500 u of the center of fovea.

Any hard exudates associated with area adjacent retinal thickening at or within 500 u of the foveal center.

Any area of retinal thickening of 1 DD or more in size at least a part of which 1 DD of foveal center

The area results have shows that Argon laser photocoagulation applied as focal laser to leaking micro aneurysm and capillaries or in a grid fashion for more diffuse edema considerably reuces the severity patients over a period of 3 years. This difference was visible angle compared to 33% of untreated patients over a period of 3 years. This difference was at 1 year of the treatment and continued at 7 years follow up. Eyes receiving focal treatment were more likely to improve visual acuity 17% versus 5% in the untreated eyes. The ETDRS has established thet main benefit of laser treatment is in prevention of visual loss than improvement of vision.

Scatter treatment is of effective in macular edema and is a bad treatment strategy. In the EDRS complications reported of laser treatment included scotoma , choroidal neovascularisarion, progressive enlargement of laser scars and subretinal fibrosis.

In our experience, we found that the closure of microaneurysm is a delayed process and it takes evev upto 3 months for the microanenrysm to close after laser photocoag, though majority of these close between 1 to 3 weeks. Hypertension, increasing age of the patient and nephropathy were found to associated with poor prognosisi. Frequencies doubled Nd Yag was to be as effective as argon green and krypton red laser photocoagulation in CSME.

Epiretinal Membrane : Diagnosis and Mamnagment-Dr. Karobi Lahiri, Bombay

Epiretinal membrane is a proliferation of membranes along the internal limiting membrane.

This is within the macular area nad is known by several terminologics. The causes are several ranging from ldiopahthic to post surgical to post inflammatory to post prolif retinopathies – being the major groups. This condition complicates 4-8% of otherwise successful retinal detachement. The apperinaces and signs depends on cell type, membrane thickness and presence of blood. The symptoms, signs choice of cases for surgery, methods of peel, complication and expectancy of visual return based on time elapsed will be discussed.

Macular Hole Surgery-Dr.Sandeep Saxena , Lucknow

A)Introduction

Macular holes were long considered a relatively common but untreatable lesion. Initially trauma & cystoid macular degeneration were usually considered the principle causes, however now it is agreed that the most important causes of macular holes is idiopathic & that vitero-retinal traction is the probable cause(whether it be A-P or t angential traction). The understanding of macular holes becauses clearer in 1998 when gass introduced the concept of tangential vitreous traction & proposed a classification for macular holes. The pre-foveal cortex was thought to primarily blame for the same.

B)classification

I Fovel detachment: yellow dot(la) or yellow halo sign(lb)

-Patient experience mild blurring /distortion of vision.

-May resolved spontaneously

III: Fully developed macular holes

-Large Central defect (500um or more)

-Cuff of SRF

-Operculum+

-No vitreous detachment on bimicroscopy.

IV : Macular hole with PVD

-Presence of a ueiss ring

-Operculum

C)Surgical & outcome consideration

a) state I : Many (over 50 %) resolve spontaneously. No surgery recommended.

b)Surgical consideration for full thichness holes:

I) A standard 3 port pars plana vitrectomy.

II) Removal of posterior hyaloid (Active /passive suction)

III) Removal of any ERM

IV) Gas-fluid exchange

V) Extended postoperative positioning (for gas tamponade of hole)

D) Controversial aspects of MHS

a) Anatomic & functional closure+(learning curve for surgeon )

b) Extended post – operative positioning difficult.

c) Age of patient

d) Duration of macular hole

e) Occurrence of iatrogenic break+

f) Cataract formation secondary to gas bubble

g) Vascular occlusions(immediate post-operative due to iop)

Advances in submacular surgery-Taraprasad das , Hyderabad

Advances in submacular surgery included better understanding of pathophysiology of submacular diseases, improved selection criteria, microsurgical instrumentations, and finally use of adjuvants, such as subreinal photocoagulation, TPA and perfluorocorbon liquid.

The current treatment approach mainly involves removal of aberrant tissue. It is likely that this approach will be supplemented with replacement of healthy differented cells both rescue and replacement of retinal photoreceptors and pigment epithelium.

Indirect Opthalmoscopy in the Detection of Retinal Breaks-Dr. Navin sakhuja, New Delhi

Indirect Opthalmoscopy is an invaluable tool for retinal surgeon and the importance of this instrument can never be understand. Doing a good indirect examination is therefore the first and most important skill that a retinal surgeon needs to acquire.

Various methods of examining by indirect Opthalmoscopy and depression Opthalmoscopy and their role in the detection and retinal breaks will be highlighted.

The optics and the principle of the technique would also be discussed.

Scleral Buckling in RD : practical approaches -Dr. B.Ghosh , New Delhi

Scleral buckling is an effective surgical technique for the repair of rhegmatogenous retinal detachment. It not only cause an apposition between the retinal pigment epithelium and neurosensory retina but also release the vitreous traction on the retinal break. The most critical aspect of scleral buckling is accurate buckle the sclera. Explants may be of solid silicone rubber sponge. Solid silicone rubber may be straight symmetric tire and asymmetric tire. Unlike the straight implants the tire implants which have a radius of curvature that approximates the shape of the globe, are preferable. Asymmetric tries provides additional advantage of increased buckle height posteriorly and minimal chances of anterior extrusio due to thinner anterior edge of the element . Silicone sponges have many small air filled pockets that give the sponge great compressibility and elasticity. This provides rounded buckling contour and adjustability of the height of indentation by varying the distance for infection. Explants may be radial or circumferential. The latter may be encircling or segment. Radial eplants are preferred over circumferential for closing wide horseshoe tears because they cause much less fishmouthing at the posterior edge. They are also recommended for very posterior breaks. Explants are secured to the sclera by a horizontal matters suture. A spatulated needle with 4-0 or 5-0 non-absorbable suture(Dacron, supramid or polypropylene) is passed at ½ - ¾ depth . the sutures are placed a minimum of 2 mm further apart than the width of the scleral buckle. After each suture tightening, visulisation of central retinal artery ascertains that the artery continous to perfuse. The buckle placement should be such that the posterior edge of break lies on the crest or anterior slope of the buckle. A solid silicone bad, 2-5 mm wide is often used to maintain longlasting indentation effect. Implant technique are often not practiced because they are time consuming and make re-operation difficult due to changes of scleral rupture, infection and late intrusion of buckling material. Sclearl buckling can result in several complications included angle closure glucomia anterior segment ischemia infection and extrusion of buckle choroidal detachment cystoid macular oedema diplopia decressed ocular rigidity changes in refractive error and falure to reattach.

Role of Vitreous Surgery in Primary Rhegmatogenous Retinal Detachment-Dr.Atul Kumar ,    New Delhi

Rhegmatogenous retinal detachment occurs due to the entery of viterious through the retinal break into the sub` retinal space and due to the traction from viterious on the anterior surface of the retina. In conventional surgeries the viterious traction is relived by a screal buckle cryo, diathermy or laser seals break and SRf is drained. But when the traction on the retina is permanent and progressive, removal of traction by parsplana vitrectomy will be the best remady for keeping the retina reattched permanently.

Vitrectomy not only helps in reliving traction on the retina but also enables the surgeon the use of interaviteral substances to tamponade the retina. Removal of intraocular foreign bodies disclosed lens dislocated IOL itc. Also can be performed along with retinal detachment surgery if necessary. Retinotomies pre-retinal and sub retinal membrane removal etc. are posiable only by the ue of vitreous surgery in rhegmatogenous retinal detachement complicated with PVR . when the retinal detachment is associated with gaint tear vitrectomy along with use of perfluorocarbon liquid helps the retina to unfold and get re-attached.

Indication for vitrectomy in Rgegmatogeneous retinal detachment :

1 Rd with PVR especially grade ‘c’ nad ‘d’

2 Rd associated with vitereous haemorraghage

3 Rd associated with intro ocular foreign bodies

4 Rd associated with gaint tears or macular hole

5 Rd with mutiple horseshoe breaksand/ or posterior beaks

6 Pseudophaika and aphakic retinal detachment with vitreous disturbance

7 Re – opertions

8 Post Inflamation RD

Indications vary from surgeon to surgeon and is only a guidance in decision making regarding the procedure to be adopted in a given situation for getting the retina permanently RE-attached. Vitrectomy has become a less risky procedure and there is a tendency to perform vitrectomy internal drainage of SRF enddo and internal tamponade even in uncompleted ehegmatogenous retinal detachment as a substitute for conventional buckling, cryo and external SRF drainage. With the development of modern gadgets like endo Laser ,BIOM and modern materials like expandable gases and perflurio carbon liquid , parsplana vitreous surgery can be very predictable and safe surgical modality to reatach the retina and may even substitute and replace conventional retinal detachment surgery soon.

The procedure is less traumatizing to the eye and post operative inflammation and pain are much reduced when compared to the conventional surgery. Beside this muscle related problems like postoperative diplopia squint etc can be almost eliminated if "internal retinal re-attachment surgery " is performed. In conventional retinal detachment surgery the sclera is penalized, occasionally leading to even necrosis even though the disease is not in the sclera but in the retina and vitreous. It only rational thinking that when we treat a disease we should treat the diseased part of the organ rather than the healthy part. It is still more deplorable to make a healthy part diseased in the process of treating an unhealthy part. Now we have fairly good and safe gadgets to perform vitreous surgery and a good number of surgeons have acquired the skill. Hence it is always worth considering vitreous surgery for all primary rhegmatogenous retinal detachments so that scleral and muscle related problems can be avoided and post operative in flammation can be reduced.

Pneumo – Retinopexy -Dr.Rajiv Mohan, New Delhi

The first Intravitreal air injection for retinal detachment repair was done Ohm in 1911. Hilton and Gizzard introduced the term "Pneumatic Retinopexy and reported their series in 1984.

Pneumatic Retinopexy (PR) is an alternative to scleral buckling for the surgical repair of selected retinal detachments. A gas bubble is injection into the vitreous cavity sealing the tear and causing absorption of the subretinal fluid. Cryotherapy or laser photocoagulation is applied around the retinal break(s) to form a permanent seal.

In retinal detachment with macula detached for less than 2 weeks it has lesser morbidity and better visual results. The success rate is up to 80% -85% and with reattachments after recperations in 95% - 98%

Intravitreal Gas Duration and Expansion

Gas Average Duration Largest Size Average Expansion

Air 3 days Immediate No expansion

SF6 12 days 36 hours Doubles

C3F8 38 days 3 days Quadruples

Ideal patients are those who are capable of maintaining a certain posture for few days having no back problems or domestic constraints and have no significant other ocular disease. The break are within one cock noon, sincerely, with no significant PVR and clear media.

Some specific indications for doing PR are thin sclera posterior retinal breaks, scarred conjunctiva, opticpit with macular detachment operating facilities not available and financial constraints.

Prophylaxis of Retinal Detachment -Dr.R.B.Jain

We know that prevention is better than cure and the proverb ‘A’ stich in same time save none probably applies maximum to retinal breaks. Prophylactic treatment may be necessary for areas of retinal degeneration which are pre disposing to retinal break formation or when breaks have already formed. The treatment is to prevent occurrence of rhegmatogenous retinal detachment. Preventive treatment should be done at the earliest possible. It is essential to do so in case of horseshoe retinal tears with attached operculum in symptomatic breaks and in large sized breaks. It will be helpful to remember that superiors break are more dangerous than inferior breaks equatorial breaks are more dangerous than holes near the oraserrata and breaks with pigment around them are less dangerous. Pre-disposing retinal degenerations specially degeneration should also be treated prophylactically.

CONFOCAL SCANNING LASER OPHTHALMOSCOPE FOR USE IN FLUOURSCIEN ANGIOGRAPHY AND INDOCYANINE GREEN ANGIOGRAPHY -DR INDU SINGH , AMRITSAR

In this paper the author shall share for brief experience in the use of the SLO is that fluorescein is excited by a blue visible light of 490nm. Indocyanine green is excited with infrared light of 800nm. Infra red light penetrates the rpe hence it is possible to do simultaneous FFA & ICGA, thus imaging the retinal and choroidal vasculature at the same time.

The SLO can also be used to take transverse section images of the retina or any elevted lesions in the retina to enable the angiographic study of not only the surface but also into the depth of the lesions.

Basic Vitreous Instrumentation

Modern vitreous surgery has changed the outlook number of vitreoretinal disorders that were hither to considered incurable.

Basic instruments like multifunctional instruments operating microscope ocutome light pipe and MVR knife and recent advantages in vitreo-retinal instrumentation like the wide angle observation system curved vitreous instruments retinal brush flute needle vitreous forscope and scissors scratches and peelers has revolutionized modern vireous surgery. Additionally intraocular diathermy, cryo, endolaser various liquid and gaseous vitreous substitutes are required for advantage vitreous surgery.

A through understanding of the basic principles and the use of these instruments can bring about a successful vitreoretinal surgery.

Vitreous Surgery for the Anterior Segment Surgeon -Dr.Atul kumar New Delhi

Various inpostal information for vitrectomy which can & may be performed by the anterior segment surgeon exist. Some of the following are :

1. Vitreo corneal touch

2. Vitreous loss during cataract surgery

3. Infantile cataract pars plana lensectomy

4. Dislocated lenses removal

5. Membranectomy

6. Aphakic papillary block including mailigant quakama

7. Post uveitis cataract with plastered iris.

8. Retro lental IOL membranes (not responding to YAG laser treatment )

Management of dropped Lens and IOL into the vitreous-Dr.Indu Singh , Amritsar

With the increasing number of phacoemulsification operations being carried out the Vitreo-retinal surgeons are frequently coming across cases with dropped nuclear fragments into the vitreous. Similarly there are a number of patients with partial or complete immersion of the posterior chamber IOLs into the vitreous. These are the patients which if tackled properly, can yield fruitful results

The Lens in Vitreo Retinal Surgery -Dr.Cyrus M Shroff , New Delhi

Modern day vitreoretinal surgery demands excellent visualization of the vitreous cavity the vitreoretinal interface the retinal surface and even the subretinal space. Often surgical manoeuvres have to be performed in the anterior vitreous base and clarity body region. The decision to preserve or remove the lens depends on two basic factors a)clarity of lens and b) type of pathology being with. This decision making process can be summarized well in surgical algorithm.

In an intraocular lens is in situ it is usually preserved if it is well placed and offers a good visualization. An important indication of its removal is a rent in the posterior capsule, which permits gas or silicon oil to come into anterior chamber in front of the intraocular lens.

Apart from idiopathic G.R.T.s risk factors for G.R.T. formation include, myopia in excess of 10.00 dioptear, blunt ocular trauma progressive areas of white with pressure and syndromes such as Marfan’s, Ehlers Danlos and Wagner- Stickler .

The introduction of perflurocarbon liquids by change at more than a decade ago has greatly facilitated the management of G.R.T. in recent years. However controversies still exist as to the need, impact and importance of scleral buckling and lensectomy in giant tear surgery. In general a lens sparing vitrectomy can be attempted if the objectives of a good vitreous base clean up can be achived without sacrificing the lens. A scleral buckle on the other hand may not be necessary in G.R.T.s greater than 270 degrees in circumferential extent.

Blunt Ocular Trauma : manifestations and Management -Dr.Shobhit Chawla , Lucknow

Blunt ocular trauma is the most common type of eye injury, it cause protein abnormalities in the posterior segment vision can be unaffected or completely lost. Manifestation range from commutes retina retinal pigment epithilium contustions choroidal ruptures, traumatic retinal tears and detachments, macular holes, to devastating optic nerve evulsions 70% to 80% of the traumatic retinal detachments are due to blunt trauma retinal dialysis being one of the common type of retinal break. Vitreous base avulsion appears to be path gnomonic for retinal detachment resulting from contusions. Posterior vitreous detachment and localized vitreous liquefaction also lead to specific type of retinal breaks. Most of these retinal detachments can be treated successfully with laser photocoagulation cryopexy, buckling procedures and Vitreo retinal procedures.

The socio – economic implications of ocular trauma are enormous. Both research and education are desperately lacking in this major field. It is important for the ophthalmologist to participate in the prevention of eye trauma as it is to recognize and treat its protein manifestation.

Injury investigations and treatment strategy.- Dr.S.Natarajan , Mumbai

Penetrating injuries of the posterior segment and performing injuries are a common cause of visual disability throughout the world.

Eyes with penetrating or perforating injuries but with clear media may require only a primary restoration of globe integrity and close observation. These cases are intervened later according to the vitreoretinal condition.

Eyes with opaque media require primary closure of wound. Investigations like B scan and CT Scan is require to detect the vitreoretinal status and vitreous surgery usually is done after about 10-15 days to manage complications. Eyes with infection or investigations and surgical management will be discussed.

All magnetic and non-magnetic intraocular foreign bodies should be removed with very few exceptions. Prior to the advent of pars plana vitrectomy all magnetic intraocular foreign bodies were removed external magnate. The prognosis for better vision had improved very much with advances in the surgical techniques and instrumentation such as endolaser, trans-scleral cryopexy , long term gas or silicone oil temponade etc.

Indirect opthalmoscopy is the best way of localization in clear media but x-rays, CT-scan and ultrasonography are the methods of choice to localized body in hazy media which are accurate in the management of intraocular foreign bodies. The benefiacl for vitrectomy in the management of intraocular foreign body, include :

Concurrent intraocular damage including

Vitreous haemrrhage

Retinal tear/detachment

Cataract formation

Encapsulated intraocular foreign body

Intraretinal foreign body

Clinical signs of endophtalmits

Several factors have to be considered including :

1. Timing of surgical intervention

2. Type of surgical intervention

3. Use of antibiotics and route of administration

While small foreign bodies can be removed by intraocular rare-earth magnet, the large ones and non-magnetic foreign bodies are removed by Intravitreal forceps. The complications and the final prognosis depend not only on the nature of the injury, the type of the intraocular foreign body but also on the complications of surgical technique involved.

Post operative endophtalmits is most devastating complication an ophthalmologist can come across during his professional carrier. No where else in ophthalmology preventive measure, early diagnosis and treatment is as important.

Because of these measures, developed countries are able to bring down incidence to <0.1% though no hard data is available due to widespread camp surgeries incidence in India is likely to be higher. Diagnosis is mainly dependent on vigilance of ophthalmologist any deviation from normal expected postoperative path for any particular ophthalmologist should raise doubt.

As most of the causative organisms are friend turning foe common sells only overt risk factors like local infection, septicemia, poor hygiene debilitating condition can be taken care of.

Vitrectomy in Endophtalmits -Lalit Verma , New Delhi

Vitrectomy for endophtalmits might be required either in Acute Stage or in resolved stage. In the resolved stage, vitreous surgery is generally a simple job, if there is no retinal detachment the surgery being facilitated by the presence of total PVD. However , in acute stage of endophtalmits ie in the presence of active infection, vitreous surgery is tricky and not so simple job. A 6 mm infusion cannula is recommended after sclerotomy with a sharp MVR blade. The problems genrally encounterd include corneal haze, corneal folds, A-C haze, membrane over anterior and posterior surface of IOL, choroidal thickening and congestion (hence the need for 6 mm Cannula ),necrotic & friable retina .The three cardinal principal to be remembered while doing vitrectomy for endophtalmits are : Use maximal cutting rate, minimal suction and do not attempted to induce a PVD if not already present. No attempt should be made to go very close to retina. At the of vitrectomy, it is generally recommended to give an Intravitreal antibiotic injection (1/10^th of regular dose) although vitrectomy is not the procedure of choice in all endophtalmits cases, it is generally required if (a) patient fails to respond to Intravitreal antibiotic injection, (b) in severe cases which have initial VA of PL only, (c) in fungal endophtalmits and (d) in traumatic endophtalmits with RIOFB.

Penetrating Trauma and Endophtalmits-Tara Prasad Das , Hyderabad

Infection resulting from penetrating ocular trauma is a clinical challenge. Non-surgical trauma is involved in 25% of cases of endophtalmits, and 2% to 7% of all penetrating injuries result in culture proven endophtalmits. The causative organisms are bacillus species, streptococcus species and Gram-negative organisms including Pseudomonas aeruginosa. The spectrum of infecting organism is seemingly different than post cataract endophtalmits. These organisms cause massive ocular destruction as they are more virulent over time despite prompt and aggressive treatment. The prognosis also depends also depends on associated ocular damage.

Metatstatic Endophtalmits : Etiological Factors and Management -Dr.Puneet Gupta Ghaziabad

This presentation reviews the published reports of Bacterial, Fungal and Viral causes of Metastatic Endophtalmits.

Infectious emboli from a focus of infection can lead on to Metastatic bacterial Endophtalmits. The source of infection is not always found. Underlying systemic debilitating disorders may predispose to this condition. The spectrum of causative bactria has changed significantly with displacement of meningococcus by Bacillus as the most frequent.

Endogenous mycotic endophtalmits is an infrequent complication of systemic mycosis. The role of systemic debilitating conditions like chemotherapy, drug abuse, malignancy, antibiotics, steroids, indwelling catheters and immuno suppressed states leading to systemic mycosis is know. Candida, aspergillus and coccidiodes are the common species.

An aggressive diagnostic and therapeutic may result in preservation of useful vivsion. Appropriate local and systemic antibiotics and antifungals should be used as therapy. Controversy currently surrounds the management of this condition because of uncertainty about the value of and indications for vitreous surgery.

Metastatic endophtalmits remains a challenge despite the success of newer drugs in reducing its frequency and severity.

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