POST VITREORETINAL SURGERY GLAUCOMA.pptx

Post Vitreoretinal Surgery Glaucoma

1. Speaker: Dr Surbi Taneja Buddy: Dr Mansi Johri Moderator: Dr Suman Bandil Chairperson : Dr Swati Singh

2. GLAUCOMA POST-VR SURGERY

3. CASE 1. 61 Year old male presented to OPD on 7/November,2019 S/P L/E MICS+IOL+PPV+Membrane peeling +FAE+SOI+Endolaser on 27/05/2019 S/P SOR L/E was done on 29/08/2019 Patient was using pilo @% tds and timolol and brimonidine combination BD L/E

4. Right eye Left eye Unaided Visual acuity (Snellen’s chart) 6/18(p ) 6/60 Best corrected Visual acuity 6/9 with +2DS /-1.00DC@40 6/36 with -2DS/-0.5DC @65

5. RIGHT EYE LEFT EYE Lids and adnexa Normal Normal C onjunctiva (Palpebral, bulbar and forniceal) Normal CONGESTION Sclera and Cornea Normal; normal size & shape C orneal haze present Anterior chamber Q uiet, no cells , no flare Van herrick grade – 3 Van herrick grade – 2 Silicon oil droplets in AC Iris Normal in color and pattern Inferonasal PI Pupil Central, reacting to light mid dialed/tonic Lens C lear pseudophakic

6. Silicone Oil behind the IOL Emulsified Silicone Oil droplets in AC

7. FUNDUS (90 D SLE; dilated) RIGHT EYE LEFT EYE MEDIA CLEAR CLEAR DISC Myopic disc Vertical Cup disc ratio :0.4:1 H azy view ,pale disc Peri -papillary area B eta zone of ppa present B eta zone of ppa present VESSELS A:V ratio 2:3 A:V ratio 2:3 MACULA Normal FR dull Normal FR dull Peripheral RETINA Normal 360 degree L aser spots seen R etina attached

8. RIGHT EYE LEFT EYE GAT 18mmHg 40mmHg GONIO 3-4 3-4 3-4 3-4 TM SEEN IN SMALL AREA TM PAS PAS PAS

9. TREATMENT GIVEN 1.Tab Acetazolamide 250mg TDS with pot chlor syrup TDS I tsp for 2 days f/b BD for 2 days 2.Timolol and Brimonidine combination eye drops BD L/E 3.Brinzolamide eye drops TDS L/E 4.Lubricating Eye drops QID B/E

10. On followup, IOP did not reduce and patient underwent Trabeculectomy with MMC L/E Post operative Bleb well formed

11. Case 2. 46 year old man presented to Opd referred by retina surgeon on 26 dec,2020 S/P PPV+MP+EL+C3F8 R/E on 7/11/20 k/c/o vasculitis L/E Using eye drops Gatiquin P 4 times a day R/E Right eye Left eye Unaided Visual acuity (Snellen’s chart) 6/36(p ) 6/12 Best corrected Visual acuity 6/9 with +2DS /-1.00DC@40 6/9 with -2DS/-0.5DC @65

12. RIGHT EYE LEFT EYE Lids and adnexa Normal Normal C onjunctiva (Palpebral, bulbar and forniceal) Normal CONGESTION Sclera and Cornea C orneal haze present Normal; normal size & shape Anterior chamber Q uiet, no cells , no flare Van herrick grade – 1 Van herrick grade – 2 Iris Peripupillary NVI superiorly Normal in color and pattern Pupil mid dilated Central, reacting to light Lens clear clear

13. FUNDUS (90 D SLE; dilated) RIGHT EYE LEFT EYE MEDIA CLEAR CLEAR DISC Myopic disc Vertical Cup disc ratio : 0.55: 1 Myopic disc Vertical Cup disc ratio : 0.4-0.5:1 Peri -papillary area B eta zone of ppa present B eta zone of ppa present VESSELS A:V ratio 2:3 A:V ratio 2:3 MACULA Normal FR dull Normal FR dull Peripheral RETINA 360 degree L aser spots seen R etina attached Normal

14. RIGHT EYE LEFT EYE GAT 52mmHg 2 0mmHg GONIO 1-2 1-2

15. REATMENT GIVEN I/V Mannitol Injection 250cc stat after checking BP Tab Acetazolamide 25omg 2 tab stat f/b TDS with pot chlor syrup Post Mannitol IOP R/E = 40mmHg E/D timolol and brimonidine combination BD E/D Dorzolamide TDS E/D Travoprost HS L/E

16. Vitreoretinal surgery is the third most common ocular surgery following cataract surgery and laser vision correction IOP elevation, either transient or sustained, is a common complication associated with retinal surgeries Incidence: 19-28% A nderson et al. reported a 5–12 h IOP spike above 29 mm Hg in 8.4% patients after vitreo-retinal surgery, which included both scleral buckle and pars plana vitrectomy. The prevalence of primary open-angle glaucoma in eyes with a retinal detachment has been reported to be 4 to 12 times higher than in the general population

17. Soon after a retina operation, the eye is often congested, painful, and with poor vision; the patient may be uncomfortable, somnolent, and at times nauseated, particularly if the surgery is performed under general anesthesia. Thus , the signs and symptoms of a secondary glaucoma in the early postoperative period can be confused with the expected side effects of vitrectomy or scleral buckle surgery . An awareness of this complication and its different presentations will facilitate recognition as well as allow for timely treatment and, in some instances, prevention of the complication.

18. GLAUCOMA AFTER SCLERAL BUCKLE

19. The incidence of angle-closure glaucoma after scleral buckling procedures has been reported to range from 1.4 to 4.4 % PATHOGENESIS: impaired venous drainage through the vortex veins by the scleral buckle, leading to congestion and swelling of the ciliary body. As the ciliary body swells, it rotates anteriorly and shifts the lens-iris diaphragm forward. UBM picture showing anteriro rotation of Cilliary body due to odema

20. Depictions of ciliary Body rotation and AC depth

21. An anterior segment ischaemia in the post-operative period, following a high buckle, may be accompanied by an increase in IOP, corneal edema and fibrin in anterior chamber * . Reduction in choroidal blood flow can induce visual field changes in open angle glaucoma patients, even without an increase in IOP, similar to that seen in normal tension glaucoma Several factors are associated with the development and extent of angle shallowing, including P re-existing narrow angles U se of an encircling band P lacement of an encircling band anterior to the equator High myopia Older age Postoperative ciliochoroidal detachment *Mowatt L. Secondary glaucoma after vitreoretinal procedures. In: Glaucoma-current clinical and research aspects. InTech, 2011.

22. TREATMENT OF ANGLE-CLOSURE GLAUCOMA AFTER SCLERAL BUCKLING SURGERY

23. These patients often present a surgical challenge because conjunctival scarring and recession from prior retinal surgery may make standard filtering surgery technically difficult and unlikely to succeed, even with the adjunctive use of antimetabolites Laser iridotomy is generally not useful, as pupillary block does not typically play a role in the pathogenesis of angle-closure glaucoma after scleral buckling procedures. Laser iridoplasty, however, may result in reopening of the angle and reduction in IOP. Glaucoma drainage devices (GDDs) offer a useful alternative

24. *Aqueous tube shunt to a preexisting episcleral encircling element in the treatment of complicated glaucomas. Sidoti PA, Minckler DS, Baerveldt G, Lee PP, Heuer DK Ophthalmology. 1994 Jun; 101(6):1036-43. **Baerveldt drainage implants in eyes with a preexisting scleral buckle. Scott IU, Gedde SJ, Budenz DL, Greenfield DS, Flynn HW Jr, Feuer WJ, Mello MO Jr, Krishna R, Godfrey DG Arch Ophthalmol. 2000 Nov; 118(11):1509-13. Sidoti et al. described the implantation of a silicone tube to shunt aqueous humor from the anterior segment to a preexisting episcleral encircling element, thereby using the fibrous capsule around the buckle as a reservoir for aqueous collection. Successful control of IOP with or without medication was achieved in 11 of 13 (85%) of eyes. * Scott et al. described the technique of inserting a full-sized 250-mm2 or 350-mm2 Baerveldt glaucoma implant (BGI) in 16 eyes with preexisting episcleral bands. The quadrant with the least amount of retinal hardware was selected for implantation, and the implant was placed over or behind the encircling band with an effort to excise the capsule overlying the band. **

25. A.capsule over scleral explant (dashed line), then passed through 20-gauge needle track anteriorly before scleral fistulization, anterior chamber in- sertion, and placement of scleral patch graft. B, capsule incision closed with running 8-0 or 9-0 polyglactin suture on a vascular needle.

26. GLAUCOMA AFTER PARS PLANA VITRECTOMY -Incidence: 11.6 and 20% -Acute post operative increase in IOP can be due to 1.Replacement with intra ocular tamponade(Gas/Silicone oil) 2.U se of intra operative endo-photocoagulation 3. P ost operative fibrinous inflammatory reaction. -Late onset glaucoma can be due to 1. T opical steroid usage 2. P re existing causes such as angle recession or neovascular glaucoma Acute rise in IOP has also been demonstrated during minimally invasive vitreo-retinal surgeries The rise mostly occurs during trocar insertion and can be prevented by modifying the technique of insertion from a direct insertion to a twisting manoeuvre.

27. Pathogenesis: Surgical inflammation and debris can reduce the aqueous outflow, alter the biochemical environment due to the release of diffusible factors after removal of cortical vitreous and can increase the susceptibility of optic disc to glaucomatous damage Pars plana vitrectomy can induce raised intraocular pressure within 2 hours (Desai, 1997), whether on its own or combined with lensectomy, scleral buckling and endolaser due to fibrin formation.

28. Chang et al. proposed that in non vitrectomised eyes, there exists a gradient in the oxygen tension in vitreous, the highest being near the retinal surface, decreasing gradually as we reach the anterior vitreous and posterior to the lens. In vitrectomised eyes, oxygen tension near the lens rises to 2–3 times the pre-operative levels. In phakic eyes, this increase in oxygen behind the lens causes nuclear sclerosis, while in pseudophakics and aphakics, this increase in oxygen tension leads to change in the extracellular matrix in trabecular meshwork and thereby reducing aqueous outflow . In the phakic eye, the lens is protective by metabolizing most of the oxygen; but after cataract surgery, the trabecular meshwork is subjected to oxidative damage by an increased oxygen level from the vitreous. This explains the increased risk of glaucoma in pseudophakic and aphakic eyes after vitrectomy

29. In the nonvitrectomized phakic eye, the oxygen tension (pO2) is lower (arrow) in the center of the vitreous than in the vitreous near the retinal surface. After vitrectomy, the gradient disappears, and oxygen tension (pO2) increases (arrow) in the central vitreous, surrounding the lens, eventually causing catara

30. (Left)After cataract surgery, the increased level of oxygen in the vitreous no longer is metabolized by the lens and mixes with aqueous humor that passes through the trabecular meshwork (arrows). pO2 􏰀 oxygen tension. Flow diagram of the role of oxidative stress that is hypothesized to cause an increase in nuclear cataract and open angle glaucoma. The presence of a human lens delays the development of open angle glaucoma.

31. Management Medical management is the first line of therapy for elevated intraocular pressure I/V Mannitol can be given in cases with High IOP for short term reduction The IOP lowering effect of mannitol could be due to both direct osmotic mechanism (removal of water from the aqueous humour in the anterior chamber and in the floor of the vitreous cavity, vitreous, and uvea) as well as central mechanism via osmoreceptors.

32. Inoue et al. reported the success rate of trabeculectomy with adjunctive Mitomycin-C to be 55.1% at 1 year, decreasing to 43.1% at 3 years. They proposed that high preoperative IOP and neovascular glaucoma are risk factors for failure Glaucoma drainage implant can be considered when there is a high risk of failure with trabeculectomy or in previously failed trabeculectomy *Inoue T, Inatani M, Takihara Y, Awai-Kasaoka N, Ogata-Iwao M, Tanihara H. Prognostic risk factors for failure of trabeculectomy with mitomycin C after vitrectomy. Jpn J Ophthalmol. 2012;

33. GLAUCOMA AFTER INTRAVITREAL GAS INJECTION -Expansile gases, such as sulfur hexafluoride (SF6) and perfluoropropane (C3F8), have been widely used in pneumatic retinopexy, as well as vitrectomy and scleral buckling procedures . - Compared with air, intraocular gases have the advantage of providing a prolonged tamponade of retinal breaks to promote chorioretinal adhesions SF6(20%) SF6(110%) C3F8 PFCL gas 6.1% 11% 18% 18-59% INCIDENCE OF IOP ELEVATION

34. Mechanism of secondary glaucoma from Intraocular Gas

35. Injection of expansile gases into the vitreous cavity can produce an anterior displacement of the lens-iris diaphragm, even with the patient positioned face down. With an intraocular gas filled eye the IOP should be measured with applanation tonometry as the change to the ocular rigidity makes the schiotz reading inaccurate. SF6 doubles its size in 36 h and C3F8 quadruples in 3 days and the greatest pressure elevation occurs at the time of maximum expansion.

36. Phases of intraocular gas kinetics inside the vitreous cavity. The greatest pressure elevation generally occurs during the period of maximum gas expansion, when the rate of liquid vitreous and aqueous egress cannot keep pace with the increasing gas volume

37. Conditions to avoid in the presence of intraocular gas

38. IOP measurements should be performed with Goldmann applanation tonometry or Perkins tonometry, since pneumatic and Schiøtz indentation tonometry may underestimate IOP in gas-filled eyes.

39. Patients with intraocular gas should not undergo general anaesthesia with nitrous oxide as intraoperatively, this gas diffuses rapidly into the intraocular gas bubble and causes rapid expansion of the gas bubble, increasing the intraocular pressure Patients may use topical anti glaucoma drops at the end of surgery or be placed on oral diuretics overnight in order to ensure that there is no pressure spikes Aqueous suppressants can be used to control the intraocular pressure. When increase in IOP causes a compromise in ocular perfusion, aspiration of a portion of intravitreal gas may be needed. -Patients should always be advised to maintain a face down position to avoid forward displacement of the lens-iris diaphragm secondary to anterior pressure from the gas bubble MANAGEMENT

40. GLAUCOMA AFTER SILICONE OIL INJECTION Intravitreal silicone oil is used as an adjunct in the surgical repair of complex retinal detachments, especially in eyes with proliferative vitreoretinopathy IOP increases can occur postoperatively at any time, ranging from mild and transient to severe and permanent Incidence of glaucoma after silicone oil injection ranges from 4.8% and 48% * *Honavar SG, Goyal M, Majji AB, Sen PK, Naduvilath T, Dandona L. Glaucoma after pars plana vitrectomy and silicone oil injection for complicated retinal detachments. Ophthalmology. 1999; 106 (1):169–177. doi: 10.1016/S0161-6420(99)90017-9. Risk factors Risk factors associated with elevation of intraocular pressure following silicone oil injection include: • Aphakia • Pre-existing glaucoma • Neovascular glaucoma • Uveitis • Peripheral anterior synechiae

41. Emusified oil in AC Inverse Hypopyon Pupillary block glaucoma occurs in 0.9% of all silicone oil filled eyes. When ‘lighter than water’ oil is used the periphery iridotomy (PI) is done inferiorly (Ando’s peripheral iridectomy ) If ‘heavy oil’ is used the PI should be done superiorly as heavy oil remains inferiorly and can block an inferior PI.

42. In presence of pupillary block, the aqueous accumulates in the lower part of the posterior chamber. Aqueous pressure thus builds up in the posterior chamber and forces SO through the pupil into the anterior chamber which may block the outflow from the angles . A PI at 6-o’clock usually solves this problem but it is seen that despite a patent PI, forward migration of the oil was found in 11% It is usually difficult to detect the presence of oil in oil filled anterior and posterior chambers since the oil is transparent and is like a single large globule occupying the chambers. One way of detecting presence of oil is by seeing the cells in the chamber which have become stagnant.

43. MANAGEMENT Silicone oil removal with or without concurrent glaucoma surgery has been performed to lower IOP, but oil removal carries some risk of retinal detachment Jonas et al. found that 93.4% of patients with a secondary increase in IOP after silicone oil endotamponade had normalization of IOP after oil removal, Flaxel et al. reported that elevated IOP persisted in all eyes (62 eyes) after silicone oil removaL Patients with complete synechial angle closure would not be expected to have normalization of IOP with silicone oil removal alone When emulsified or nonemulsified oil blocks the trabecular meshwork directly, it is reasonable to proceed with silicone oil removal alone if the retina is completely attached with closure of all tears and release of all areas of traction. Patients should be warned of the possible need for subsequent glaucoma surgery.

44. Patients treated with silicone oil removal alone may still require anti-glaucoma surgery in the future, whereas a combined surgery may increase the risk of post-operative hypotony. E levated IOP can occur even after silicone oil removal due to the splitting of silicone oil droplets into smaller bubbles thus obstructing the trabecular meshwork. Emulsified silicone oil can block the ostium in superior trabeculectomy and can cause failure. Transscleral cyclophotocoagulation has been used to treat glaucoma secondary to silicone oil. Successful IOP control has been reported in 66–82% of patients at 1 year T he management needs to be individualised and these eyes need careful and lifelong follow-up.

45. GLAUCOMA POST INTRAVITREAL STEROID INJECTION Intravitreal injection of steroid has found its application in the treatment of macular edema following various conditions like diabetic retinopathy, uveitis, retinal vascular occlusions, choroidal neovascularisation and post cataract surgery. Rise in intraocular pressure is one of the most common complications following intravitreal steroid injection Incidence: 11-79% * *Kiddee W, Trope GE, Sheng L, et al. Intraocular pressure monitoring post intravitreal steroids: a systematic review. Surv Ophthalmol. 2013; 58 (4):291–310.

46. Pathogenesis: Immediate rise of IOP following injection has been attributed to the direct effect of an increase in intra-ocular volume. Delayed rise in IOP can occur due to I ncrease in accumulation of glycosaminoglycans in the trabecular meshwork Steroid induced cytoskeletal changes I ncreased expression of the Trabecular Meshwork Inducible Glucocorticoid Response (TIGR) protein and high levels of Tissue Inhibitor of Matrix Metalloproteinase (TIMP) Corticosteroids inhibit phagocytosis by TM cells that may lead to accumulation of cellular debris and increased resistance to aqueous outflow

47. MANAGEMENT These patients usually respond to topical and systemic anti-glaucoma medications. M onitor the IOP of these patients in the early post operative period so that further injections can be avoided in uncontrolled cases The IOP decreases as the intravitreal concentration of the drug decreases over 4–6 months The use of argon laser trabeculoplasty (ALT) and selective laser trabeculoplasty(SLT) have shown promising results. * Vitrectomy and removal of an intravitreal implant may be needed in susceptible patients. Filtering surgeries are recommended in cases not responding to laser and medical management. *Rubin B, Taglienti A, Rothman RF, Marcus CH, Serle JB. The effect of selective laser trabeculoplasty on intraocular pressure in patients with intravitreal steroid-induced elevated intraocular pressure. J Glaucoma. 2008

48. GLAUCOMA POST RETINAL LASER PHOTOCOAGULATION Angle closure glaucoma following PRP is caused by anterior rotation of the ciliary body secondary to a ciliochoroidal fluid and detachment. This occurs as a result of transudation of fluid from the choroidal vasculature into the choroid and suprachoroidal space secondary to a thermally induced choroiditis and choroidal vascular occlusions. Hayreh and Baines have shown that anterior chamber shallowing can be produced acutely by an obstruction in the vortex venous system Risk factors for the development of the ciliochoroidal effusion after PRP include 1.Greater number of laser applications 2. S horter axial length 3. G reater percentage of retinal surface area treatment

49. Percentage of retinal surface area treated appears to represent the most important variable for the development of effusion, although differences in PRSAT(percentage of retinal surface area treated) among eyes receiving PRP may be difficult to appreciate clinically. Eyes with shorter axial lengths have less total retinal area then eyes with longer axiallengths and will have a greater PRSAT for the same RSAT(retinal surface area treated) Threshold for the development of ciliochoroidal effusion after PRP exists for each eye and is dependent on three factors: B urn intensity, which is, in turn, dependent on the laser output parameters and the absorption qualities ofthe retina and choroid; Burn size and number, which corresponds to the RSAT; and A xial length,

50. Representative ultrasound biomicrograph illustrates normal ciliary body anatomy before panretinal photocoagulation

51. Ciliochoridal effusion after panretinal photocoagulation.

52. MANAGEMENT In the majority of cases, the angle closure and resultant IOP rise is transient and asymptomatic . Medical therapy is usually enough for treating the IOP spikes.

53. CONCLUSION Glaucoma after vitreoretinal surgery requires special attention to its etiology, pathophysiology, diagnosis, treatment, and prevention . Direct communication between the retina surgeon and glaucoma specialist will result in early diagnosis and appropriate management based on the likely etiology.