SlideShare a Scribd company logo

Principles and technique of pneumatic retinopexy (Dr. Avuru C.J).pptx

•Download as PPTX, PDF•
•
A
AVURUCHUKWUNALUJAMES1

Retinal detachment surgeries, principles and technique of pneumatic retinopexy, current trend in retinal detachment surgeries, development of skills in binocular indirect ophthalmoscopic examination, residency traning presentation, University college hospital Ibadan, Oyo state Nigeria, Vitreo-retinal subspecialty training, West african college of surgeons, federal teaching hospital, Lokoja, Kogi state, Nigeria.

1 of 68
Downloaded 11 times
Principles and technique of Pneumatic Retinopexy (PR) Presented By Dr. Avuru Chukwunalu James 21st August, 2023
OUTLINE • Introduction • Indications and contraindications • Advantages and disadvantages • Procedure/ Techniques • Complications • Conclusion
Introduction • Pneumatic retinopexy is an office-based non-incisional procedure for the repair of selected cases of rhegmatogenous retinal detachment. • Repairing of retinal detachments by retinopexy followed by gas endotamponade was first described by Rosengren in 1938. • Modernized and popularized by Hilton and Grizzard in their 1986 publication and deemed an outpatient procedure. • In the USA, 15% of retinal detachments are repaired by pneumatic retinopexy.
Introduction contd • About 16% of VR surgeons in the UK and Ireland perform regular PR. • 40% of all rhegmatogenous RD can be repaired using PR. • Under-utilized due to • Belief: relief of vitreoretinal traction • Skills in localization of retinal break. • An alternative to scleral buckle and pars plana vitrectomy in selected cases
Indications • Retinal detachment with retinal break(s) in the superior 2/3 of the fundus (from 8 to 4 o’clock) • Single or multiple breaks within 1 clock hour • Clear media or mild media opacity • No glaucoma history • Head positioning for 5-8 days after procedure
Contraindications • RD with breaks in the inferior 4 clock hours • PVR of Grade C or D. • Extensive lattice degeneration or VR adhesions. • Significant media opacity • Advanced glaucoma • Unable to maintain postoperative head positioning.
Contraindications contd • Travel to a high altitude soon after surgery • Pseudophakia or aphakia (relative contraindication)
Advantages of PR • Outpatient procedure • Less discomfort than operating room procedures • Little to no need for general anesthesia • No risk of inadvertent scleral perforation
Advantages of PR contd • No change in refractive error • No risk of diplopia • Lower risk of endopthalmitis • Faster ocular and systemic recovery • Lower cost of surgery
Disadvantages • Single-operation success rate is lower than scleral buckle and PPV(higher frequency of new and missed retinal breaks). • PIVOT trial: a single center, randomized clinical trial (Hillier et al, 2019). Compared the outcomes of primary PR in 77 eyes versus primary pars plana vitrectomy (PPV) in 73 eyes with primary RRD. Single operation anatomic success rate was better in PPV (93.2%) compared with PR (80.8%).
PIVOT trial • Final anatomic success rate was similar in both groups PPV(98.7%) and PR (98.6%). • Visual acuity outcomes with PR were superior to those obtained with PPV • The mean best corrected VA at 12 months was 79.9 letters (ETDRS) in the PR group compared with 75 letters in the PPV group. • Proportion of eyes achieving ≥ 20/40 was 90.3% in PR and 75.3% in PPV group. • Patients who had PR scored higher in mental health and vision-related functioning scores than patients who had PPV in the first 6 months following procedures.
PIVOT trial contd • Retinal displacement induced by PR was significantly less (compared to PPV). • Vertical metamorphopsia scores were superior in PR group too (compared to PPV group).
PR versus scleral buckle • Study byTornambe et al: macula involving RRD within 14 days post-op • visual outcomes: PR group better than SB group. • Chan et al(1986-2007): primary success rate in retina reattachment with a single PR procedure • in phakics to be between 71% and 84%. • In pseudophakics to be between 41% and 67%.
Disadvantages contd • Good retinal examination skills needed • Not all detachments are amenable to repair with PR • Significant patient cooperation and head positioning required • Skills in detection and management of postoperative complications needed.
PHASES OF SURGERY • PR involves 1. Injection of expanding gas bubble and patient’s head positioning.  Bubble closes the retinal break.  Permits resorption of subretinal fluid. 2. Induction of a chorioretinal adhesion around all retinal breaks with cryopexy, laser, or both.
Two steps vs one step procedure • One step surgery done in the same surgery session (the same day) • inducing chorioretinal adhesion with cryopexy • intraocular gas injection • Two steps surgery • Intraocular gas injection is done first • Then induction of chorioretinal adhesion with laser retinopexy is done 24-48hrs post intraocular gas injection when the retina is flat.
Choice: cryopexy or laser retinopexy • Lasers preffered for • Small pupil • Clear media • More posterior breaks • Retinal cryopexy is technically easier for  Higher media opacity  peripheral breaks, especially for small or hard- to-find breaks.
Pre-operative planning-materials • Instruments Sterile Gloves Betadine solution (5% and 10%) Xylocaine 1%/Marcaine 0.5% 2% Lidocaine Antibiotic/steroid ointment Lid speculum Conjunctival forceps Cotton-tipped applicators Two tuberculin syringes with two 27g 1/2-inch needles(or 30 gauge) Laser or Cryotherapy unit Intraocular gas (SF6 or C3F8) Millipore filter, 0.22 µm Indirect ophthalmoscope
Choice of Gas  Depends on required Level of expansion Duration of gas tamponade Availability Cost • Most commonly utilized intraocular gases. • SF6 • C3F8 (larger or multiple breaks) Used in their pure (100% concentration) form but usually diluted when used in vitrectomy surgery.
Intraocular gasses
Ocular Examination findings- Needed as a guide  Reconfirm all areas of pathology Visual acuity Intraocular pressure Anterior segment examination Fundus examination Media clarity Status of Optic disc Status of the macular Configuration of SRF Localization of break Fundus diagram
Anaesthesia • Subconjunctival anaesthesia + topical drops : No cryotherapy • Retrobulbar or peribulbar anaesthesia • comfortable scleral depression, • cryotherapy to any quadrant • reduces chances of vaso-vagal response • General anesthesia(rarely) • avoid nitrous oxide gas in general anaesthesia: shrinkage of intraocular gas bubble.
Procedure • Comfirm pupil is dilated • Instill 3-5 drops of topical anesthesia into the eye. • Insert lid speculum. • Subconjunctival anaesthesia to the quadrant with retinal break. • 5% povidone-iodine solution (3- 5 drops) instilled and irrigated with saline after 5 minutes.
Single sitting procedure-one step • Topical anaesthesia + retrobulbar block / peribulbar anaesthesia • External eye and fornices prepared (as above). • Trans-conjunctival cryopexy under visualization via BIO • around retinal breaks • degenerative lesions.
Cryotherapy • MECHANISM: Uses • freezing temperature to convert liquids to solids • intracellular and extracellular water to ice. • Leads to tissue death and a sterile inflammatory reaction.
Cryopexy procedure contd • STEPS: Check cryoprobe by freezing and unfreezing a few times. • Place probe over conjuctivo- scleral area with view of retinal break. • Initiate freezing • Observe for retina whitening. • Spray water on cryoprobe, wait for complete melting of ice-ball before removing from sclera. • Thaw and repeat again around retinal breaks and degenerative lesions.
Procedure contd-AC paracentesis • Done to lower the intraocular pressure. Stabilize the eye with a cotton- tip swab Use 27 or 30-gauge needle attached to a tuberculin syringe to enter the AC at the inferotemporal limbus. 0.3-0.5ml of aqueous humor is withdrawn. Softens the eye Less chances of fish-eggs bubble formation.
Procedure- gas prepation( wuthdawal into syringe) • 0.3 mL (C3 F8) or 0.5-0.6mL (SF6) • Filtered through a millipore filter (0.22 µm) into a 1-mL syringe with a 27- or 30- gauge needle.
Procedure- postioning during gas injection • Patient lying in a supine position( majority of cases). • Patient lying in the upright position (rarely) • In patients with elevated intraocular pressure; reduces tendency for a. gas migration into anterior chamber. b. vitreous prolapse into the anterior chamber.
Procedure contd • Injection site: 3mm, 3.5mm and 4mm • Patient in the supine position;  inject through a superior quadrant and away from the most bullous area of detachment • Needle • perpendicular to the sclera • point downward toward the center of the vitreous cavity.
Procedure contd • Insert the needle (depth of 6-7 mm) into the vitreous cavity. • then partially withdraw until only 2-3 mm remains in the vitreous. • Slowly and continously inject the gas into the same single enlarging gas bubble (avoids formation of “fish-egg” bubbles). • Injected away from any large retinal break
Procedure contd • During needle withdrawal, • place a cotton-tipped applicator over the perforation site • rotate patient’s head to prevent gas from escaping through the puncture site. • Perform indirect ophthalmoscopy to • confirm the placement of the gas into the vitreous cavity • assess the perfusion of the central retinal artery • confirm light perception.
Procedure contd • If central retinal artery remains non-pulsatile 10 minutes after gas injection, • paracentesis is repeated to reduce the risk for ischemic retinal damage • Antibiotic or antibiotic/steroid ointment combination applied to the eye • Patching is optional
Head positioning • Patient’s head is immediately positioned so that the gas bubble is apposed directly to the break • Macular threatening retinal detachment: • consider the steamroller technique to prevent subretinal fluid displacement into the macula.
Head positioning-steamroller technique • Head is initially turned to a face- down position. • Gradually change position over 10-15minutes until the retinal break is uppermost. • Allows the bubble to roll toward the retinal break. • Pushes the subretinal fluid away from the macula and back into the vitreous cavity through the retinal break. • Flattening the retina.
Steamroller technique- disadvantage • Potential for proliferative vitreoretinopathy development. • RPE cells within the subretinal fluid pushed back into the vitreous cavity.
Head positioning after surgery • Instruct the patient on the proper head- positioning • Clock hour drawing • an arrow in the clock hour of the retinal tear • head positioning so that the "arrow" is pointing straight up.
Post-surgery head positioning contd • Family member can take a picture of • head position while in the office • reference this picture at home to properly position. • To maintain head position for up to 16 hours per day for 5-8days.
When fish egg bubbles form • May be caused by Injection of gas too quickly Needle too deep into the vitreous during injection • Gentle tapping on the eye to make the bubbles coalesce. • positioning the bubbles away from the break for 24 hours allow them to coalesce prevent subretinal gas.
Gas migration- Canal of Petit/ anterior hyaloid • May occur if needle not inserted deeply enough needle inserted too anteriorly. • Bubble seen floating behind the lens (“donut sign” or “sausage sign”) • MGT: observe face-down positioning for 24-48hrs gas migrate into the vitreous as it expands
Anterior hyaloid gas drainage • If above fails: passive drainage via previous gas insertion site  with a 27-gauge needle on a plungerless 3-cc syringe partially filled with 1cc of sterile water. Reinjection of gas with proper needle placement can be done.
Gas migration contd- Gas in the anterior chamber • May be due to lens capsular rent zonular compromise a. Pupillary dilation followed by face-down positioning b. Anterior chamber paracentesis with a 27-gauge needle.
Subretinal gas migration • May occur if a. injection site is too close to retina break b. Inappropriately injection under the retina c. Injected with formation of “fish egg" bubbles d. Retinal breaks larger than 1 clock hour • A small amount of subretinal gas can be resorbed without positioning.
Subretinal gas migration • Larger bubble requires head positioning: a. Positioning for 24hrs so that bubbles migrate away from the tear. b. Patient lying in a supine position to release subretinal gas into the vitreous by; tilting the head so that the break is at the most superior position gentle scleral depression may release the subretinal gas into the vitreous cavity. • Pars plana vitrectomy and removal of subretinal gas to avoid expansion in the subretinal space and tear.`
Intraocular pressure changes post injection • Not a significant problem after the intraocular injection of less than 0.5 mL of gas. • Immediate elevation of intraocular pressure to levels between 30 and 50 mm Hg is common, • Pressure however returns to normal after 90 minutes. • A 0.3% incidence of ischemic optic neuropathy following elevated IOP post PR was reported by Tornambe (1997). • Elevation of IOP beyond normal can be managed with additional anterior chamber paracentesis or topical/systemic IOP-lowering drops.
Postoperative/follow up Care • Head positioning for 5-8 days to orient gas bubble at the site of the tear(s). Must position for 16 hours per day, with 15-minutes breaks each hour. • Antibiotic or antibiotic/steroid eyedrops four times per day, usually for 1 week • Examine patient daily until the retina is attached; if the retina is not attached by 2nd day post-op, suspect causes of failure. • New break, missed break, small gas size, patient not positioning adequately may cause early failure • Peripheral inferior subretinal fluid may persist for weeks to months though with a decreasing trend of SRF quantity.
Retinal Laser retinopexy • Dilate the pupil • Laser delivery system: Use slit lamp or LIO • Instill topical anaesthetic and position patient. • Laser: Argon blue-green, Nd-YAG Lasers • Duration of 0.1 to 0.2 seconds • spot sizes of 200 to 500 microns • Surround retinal break with 2-3 near- confluent rows of laser. • Supplemental lasers until SRF is completely resolved
Postoperative/follow up Care contd • 1st day post-op. • Fifth day or 1week post-op. • 2 weeks post-op. • Monthly follow-up for 3 months. • Every 3 months for a minimum of 6 months. • Management of postoperative complications and additional surgery if indicated.
Complications-subconjunctival gas • May be due to incomplete penetration of the sclera by needle leakage of gas from injection site. • Treatment is not required. • Prevent subconjunctival gas by  Proper needle insertion into the vitreous cavity  Immediate placement of cotton-tipped applicator on the injection site after removal of the needle.
Complications-Corneal wound dehiscence • Risk factors: previous cornea wound/scars • Full-thickness corneal wounds never regain their original tensile strength. • After intravitreal gas injection, sudden rise in IOP may be up to 180 mm Hg Can stress and rupture corneal scars. • Reduced by slowly injecting a smaller gas volume in patients with risk factors.
Complications-Surgical failure due new or missed breaks: New breaks with re-RD reported post PR at a rate of 7- 22%. New or missed breaks occur mostly in the superior 8 clock hour (76% ). Treat with additional gas injection + cryotherapy or laser retinopexy. Inferior quadrants new breaks  with scleral buckling and/or PP vitrectomy.
Complications-cataract progression • Not common after pneumatic retinopexy (PR). • No significant difference in lens opacity (operated vs non- operated eyes) at 2 months post PR.(Koch et al,1991) • Minimized cataract Careful placement of the paracentesis needle Avoiding contact between the intraocular gas and the lens (adequate head positioning).
Complications-endophthalmitis • Incidence post PR is very low (0.97% cases of staphylococcal endophthalmitis reported by Tornambe and Hilton (1989). • Can be reduced by a. meticulous with the sterile techniques. b. use of 5% povidone iodine solution prior to intraocular injection of gases
Complications- Intraocular/ orbital hemorrhage • Intraocular hemorrhage is rare • May be due to injury anterior ciliary vessels (injection site) rupture of scleral vessels (cryotherapy) • Reduce by avoiding injection along the vertical and horizontal meridians (anterior ciliary vessels). Tip of cryoprobe should be allowed to thaw before removal from the ocular surface.
Complications- Choroidal detachment (CD) • Not common post PR • Incidence of 3% post PR (Tornambe and Hilton,1989). • Suspect CD if prolonged and severe pain occur shortly after gas injection (gas injected into suprachoroidal space). • Pain: stretching of the ciliary nerves by the gas. • Prevent CD by Avoiding hypotony during paracentesis Reducing excessive cryotherapy
Complications-cystoid macular edema • Not common after pneumatic retinopexy. • Risk factors include history of uveitis, prior cataract extraction, and macular detachment. • Can be reduced by avoiding excessive retinopexy • Medical treatment: Topical steroidal and nonsteroidal anti- inflammatory medications.
Complications-Macular hole • May be due to vitreomacular traction during the perioperative period. • Expansion of the intraocular gas produces a vitreomacular detachment • Stress of shifting of a large amount of subretinal fluid under the macular. • Treatment is by conventional surgical techniques such as PPV.
Epimacular fibrosis and macular pucker • Incidence of 4% of asymptomatic epimacular membrane post PR has been reported. • Minimize risk by avoiding excessive cryotherapy laser retinopexy
Complications-Proliferative vitreoretinopathy • Incidence: 9.6-9.8% post PR (9.8% Chen et al, 1988) • No difference in incidence of PVR (cryotherapy versus laser): 9.6%, Tornambe, 1997. • May be caused by Excessive release of RPE cells into the vitreous Gas bubbles • PVR post PR can be treated with PPV and membrane stripping.
Complications-Musculoskeletal • Due to consistent head tilt for a prolonged period. • Worse among elderly patients. • They include cervical spine injury, neck muscles and lower back pain, ulnar nerve neuropathy. • They are minor and temporal problems. • PREVENTIVE MEASURES: Use of pillow, cushion, table, desk (with the correct height) • TREATMENT: analgesics, heating pad, muscle relaxants to relieve musculoskeletal discomfort.
Pneumatic retinopexy in inferior Breaks • PR ; an adjunctive role for RD with inferior breaks. • Studies involving maintaining an inverted posture for 8 hours following PR Restricted to highly motivated patients. IOP increases significantly in the head-down position (not indicated in glaucomatous eyes)
PR in inferior Breaks contd  After PR for inferior retinal breaks post failed scleral buckle; posturing with a combined 10° Trendelenburg position 10° neck hyperextension 10° ocular supraduction • Had 88% success rate (Mansour et al, 2005).
Pneumatic retinopexy in inferior Breaks contd • Lateral recumbent posture:77% success rate with inferior detachments. (Hwang et al, 2011) • Use of a temporary buckle in the inferior fornix combined with a face-down position with 5°–10° of neck flexion achieved 88% primary reattachment success. (Cheng et al, 2013). • Previous SB or PPV has been done in majority of these patients  therefore, success in PR as a primary procedure for RD with inferior retinal breaks have only few reported successful cases.
Adaptability to our environment • Cost • Complications • Visual prognosis • Skills • Time of presentation
Conclusion • Pneumatic retinopexy is currently underutilized despite its effectiveness in selected cases. • Adequate skills in BIO examination, localization of retinal breaks and patient’s motivation to head positioning are essential. • Success involves adequate surgeon’s experience, good patient selection, patience and effective doctor- patient communication.
REFERENCES • Lihteh Wu. Pneumatic Retinopexy. Medscape. Updated: Mar 13, 2023 [accessed Aug 12th, 2023]. Available from https://emedicine.medscape.com/article/1844217-overview • Christina Y, Kamjoo S, Amitabh K. Pneumatic Retinopexy. EyeWiki. Jul 26, 2023 2023.[accessed Aug 12th, 2023]. Available from https://eyewiki.aao.org/Pneumatic_Retinopexy. • Wong TY. SNG C, Lim L. The ophthalmology examinations review. Pneumatic retinopexy. 2nd Ed. Singapore: World Scientific Publishing; 2011. p. 189. • Mandelcorn ED, Manusow JS, Mandelcorn MS. Pearls for Performing Pneumatic Retinopexy. Retina specialist. November 13, 2015[ Accessed August 15, 2023]. Available from https://www.retina- specialist.com/article/pearls-for-performing-pneumatic-retinopexy • Stewart S, Chan W. Pneumatic retinopexy: patient selection and specific factors. Clin Ophthalmol. 2018 Mar 16;12:493-502. doi: 10.2147/OPTH.S137607. PMID: 29588570; PMCID: PMC5859893 • Silva RA, Blumenkranz MS. Prophylaxis for Retinal Detachments. AAO. Oct 29, 2013. [Accessed August 15, 2023]. Available from https://www.aao.org/education/munnerlyn-laser-surgery- center/prophylaxis-retinal-detachments
REFERENCES contd • Tornambe PE. Pneumatic retinopexy. Surv Ophthalmol. 1988 Jan- Feb;32(4):270-81. doi: 10.1016/0039-6257(88)90175-0. PMID: 3279561. • Chan CK, Lin SG, Nuthi AS, Salib DM. Pneumatic retinopexy for the repair of retinal detachments: a comprehensive review (1986– 2007) Surv Ophthalmol. 2008;53(5):443–478. • Cheng HC, Lee SM, Lee FL, Liu JH, Kuan CH, Lin PK. Short- term external buckling with pneumatic retinopexy for retinal detachment with inferior retinal breaks. Am J Ophthalmol. 2013;155(4):750.e1–756.e1. • Hwang JF, Chen SN, Lin CJ. Treatment of inferior rhegmatogenous retinal detachment by pneumatic retinopexy technique. Retina. 2011;31(2):257–261. • Mansour AM. Pneumatic retinopexy for inferior retinal breaks. Ophthalmology. 2005;112(10):1771–1776.
THANK YOU

More Related Content

Principles and technique of pneumatic retinopexy (Dr. Avuru C.J).pptx

  • 1. Principles and technique of Pneumatic Retinopexy (PR) Presented By Dr. Avuru Chukwunalu James 21st August, 2023
  • 2. OUTLINE • Introduction • Indications and contraindications • Advantages and disadvantages • Procedure/ Techniques • Complications • Conclusion
  • 3. Introduction • Pneumatic retinopexy is an office-based non-incisional procedure for the repair of selected cases of rhegmatogenous retinal detachment. • Repairing of retinal detachments by retinopexy followed by gas endotamponade was first described by Rosengren in 1938. • Modernized and popularized by Hilton and Grizzard in their 1986 publication and deemed an outpatient procedure. • In the USA, 15% of retinal detachments are repaired by pneumatic retinopexy.
  • 4. Introduction contd • About 16% of VR surgeons in the UK and Ireland perform regular PR. • 40% of all rhegmatogenous RD can be repaired using PR. • Under-utilized due to • Belief: relief of vitreoretinal traction • Skills in localization of retinal break. • An alternative to scleral buckle and pars plana vitrectomy in selected cases
  • 5. Indications • Retinal detachment with retinal break(s) in the superior 2/3 of the fundus (from 8 to 4 o’clock) • Single or multiple breaks within 1 clock hour • Clear media or mild media opacity • No glaucoma history • Head positioning for 5-8 days after procedure
  • 6. Contraindications • RD with breaks in the inferior 4 clock hours • PVR of Grade C or D. • Extensive lattice degeneration or VR adhesions. • Significant media opacity • Advanced glaucoma • Unable to maintain postoperative head positioning.
  • 7. Contraindications contd • Travel to a high altitude soon after surgery • Pseudophakia or aphakia (relative contraindication)
  • 8. Advantages of PR • Outpatient procedure • Less discomfort than operating room procedures • Little to no need for general anesthesia • No risk of inadvertent scleral perforation
  • 9. Advantages of PR contd • No change in refractive error • No risk of diplopia • Lower risk of endopthalmitis • Faster ocular and systemic recovery • Lower cost of surgery
  • 10. Disadvantages • Single-operation success rate is lower than scleral buckle and PPV(higher frequency of new and missed retinal breaks). • PIVOT trial: a single center, randomized clinical trial (Hillier et al, 2019). Compared the outcomes of primary PR in 77 eyes versus primary pars plana vitrectomy (PPV) in 73 eyes with primary RRD. Single operation anatomic success rate was better in PPV (93.2%) compared with PR (80.8%).
  • 11. PIVOT trial • Final anatomic success rate was similar in both groups PPV(98.7%) and PR (98.6%). • Visual acuity outcomes with PR were superior to those obtained with PPV • The mean best corrected VA at 12 months was 79.9 letters (ETDRS) in the PR group compared with 75 letters in the PPV group. • Proportion of eyes achieving ≥ 20/40 was 90.3% in PR and 75.3% in PPV group. • Patients who had PR scored higher in mental health and vision-related functioning scores than patients who had PPV in the first 6 months following procedures.
  • 12. PIVOT trial contd • Retinal displacement induced by PR was significantly less (compared to PPV). • Vertical metamorphopsia scores were superior in PR group too (compared to PPV group).
  • 13. PR versus scleral buckle • Study byTornambe et al: macula involving RRD within 14 days post-op • visual outcomes: PR group better than SB group. • Chan et al(1986-2007): primary success rate in retina reattachment with a single PR procedure • in phakics to be between 71% and 84%. • In pseudophakics to be between 41% and 67%.
  • 14. Disadvantages contd • Good retinal examination skills needed • Not all detachments are amenable to repair with PR • Significant patient cooperation and head positioning required • Skills in detection and management of postoperative complications needed.
  • 15. PHASES OF SURGERY • PR involves 1. Injection of expanding gas bubble and patient’s head positioning.  Bubble closes the retinal break.  Permits resorption of subretinal fluid. 2. Induction of a chorioretinal adhesion around all retinal breaks with cryopexy, laser, or both.
  • 16. Two steps vs one step procedure • One step surgery done in the same surgery session (the same day) • inducing chorioretinal adhesion with cryopexy • intraocular gas injection • Two steps surgery • Intraocular gas injection is done first • Then induction of chorioretinal adhesion with laser retinopexy is done 24-48hrs post intraocular gas injection when the retina is flat.
  • 17. Choice: cryopexy or laser retinopexy • Lasers preffered for • Small pupil • Clear media • More posterior breaks • Retinal cryopexy is technically easier for  Higher media opacity  peripheral breaks, especially for small or hard- to-find breaks.
  • 18. Pre-operative planning-materials • Instruments Sterile Gloves Betadine solution (5% and 10%) Xylocaine 1%/Marcaine 0.5% 2% Lidocaine Antibiotic/steroid ointment Lid speculum Conjunctival forceps Cotton-tipped applicators Two tuberculin syringes with two 27g 1/2-inch needles(or 30 gauge) Laser or Cryotherapy unit Intraocular gas (SF6 or C3F8) Millipore filter, 0.22 µm Indirect ophthalmoscope
  • 19. Choice of Gas  Depends on required Level of expansion Duration of gas tamponade Availability Cost • Most commonly utilized intraocular gases. • SF6 • C3F8 (larger or multiple breaks) Used in their pure (100% concentration) form but usually diluted when used in vitrectomy surgery.
  • 21. Ocular Examination findings- Needed as a guide  Reconfirm all areas of pathology Visual acuity Intraocular pressure Anterior segment examination Fundus examination Media clarity Status of Optic disc Status of the macular Configuration of SRF Localization of break Fundus diagram
  • 22. Anaesthesia • Subconjunctival anaesthesia + topical drops : No cryotherapy • Retrobulbar or peribulbar anaesthesia • comfortable scleral depression, • cryotherapy to any quadrant • reduces chances of vaso-vagal response • General anesthesia(rarely) • avoid nitrous oxide gas in general anaesthesia: shrinkage of intraocular gas bubble.
  • 23. Procedure • Comfirm pupil is dilated • Instill 3-5 drops of topical anesthesia into the eye. • Insert lid speculum. • Subconjunctival anaesthesia to the quadrant with retinal break. • 5% povidone-iodine solution (3- 5 drops) instilled and irrigated with saline after 5 minutes.
  • 24. Single sitting procedure-one step • Topical anaesthesia + retrobulbar block / peribulbar anaesthesia • External eye and fornices prepared (as above). • Trans-conjunctival cryopexy under visualization via BIO • around retinal breaks • degenerative lesions.
  • 25. Cryotherapy • MECHANISM: Uses • freezing temperature to convert liquids to solids • intracellular and extracellular water to ice. • Leads to tissue death and a sterile inflammatory reaction.
  • 26. Cryopexy procedure contd • STEPS: Check cryoprobe by freezing and unfreezing a few times. • Place probe over conjuctivo- scleral area with view of retinal break. • Initiate freezing • Observe for retina whitening. • Spray water on cryoprobe, wait for complete melting of ice-ball before removing from sclera. • Thaw and repeat again around retinal breaks and degenerative lesions.
  • 27. Procedure contd-AC paracentesis • Done to lower the intraocular pressure. Stabilize the eye with a cotton- tip swab Use 27 or 30-gauge needle attached to a tuberculin syringe to enter the AC at the inferotemporal limbus. 0.3-0.5ml of aqueous humor is withdrawn. Softens the eye Less chances of fish-eggs bubble formation.
  • 28. Procedure- gas prepation( wuthdawal into syringe) • 0.3 mL (C3 F8) or 0.5-0.6mL (SF6) • Filtered through a millipore filter (0.22 µm) into a 1-mL syringe with a 27- or 30- gauge needle.
  • 29. Procedure- postioning during gas injection • Patient lying in a supine position( majority of cases). • Patient lying in the upright position (rarely) • In patients with elevated intraocular pressure; reduces tendency for a. gas migration into anterior chamber. b. vitreous prolapse into the anterior chamber.
  • 30. Procedure contd • Injection site: 3mm, 3.5mm and 4mm • Patient in the supine position;  inject through a superior quadrant and away from the most bullous area of detachment • Needle • perpendicular to the sclera • point downward toward the center of the vitreous cavity.
  • 31. Procedure contd • Insert the needle (depth of 6-7 mm) into the vitreous cavity. • then partially withdraw until only 2-3 mm remains in the vitreous. • Slowly and continously inject the gas into the same single enlarging gas bubble (avoids formation of “fish-egg” bubbles). • Injected away from any large retinal break
  • 32. Procedure contd • During needle withdrawal, • place a cotton-tipped applicator over the perforation site • rotate patient’s head to prevent gas from escaping through the puncture site. • Perform indirect ophthalmoscopy to • confirm the placement of the gas into the vitreous cavity • assess the perfusion of the central retinal artery • confirm light perception.
  • 33. Procedure contd • If central retinal artery remains non-pulsatile 10 minutes after gas injection, • paracentesis is repeated to reduce the risk for ischemic retinal damage • Antibiotic or antibiotic/steroid ointment combination applied to the eye • Patching is optional
  • 34. Head positioning • Patient’s head is immediately positioned so that the gas bubble is apposed directly to the break • Macular threatening retinal detachment: • consider the steamroller technique to prevent subretinal fluid displacement into the macula.
  • 35. Head positioning-steamroller technique • Head is initially turned to a face- down position. • Gradually change position over 10-15minutes until the retinal break is uppermost. • Allows the bubble to roll toward the retinal break. • Pushes the subretinal fluid away from the macula and back into the vitreous cavity through the retinal break. • Flattening the retina.
  • 36. Steamroller technique- disadvantage • Potential for proliferative vitreoretinopathy development. • RPE cells within the subretinal fluid pushed back into the vitreous cavity.
  • 37. Head positioning after surgery • Instruct the patient on the proper head- positioning • Clock hour drawing • an arrow in the clock hour of the retinal tear • head positioning so that the "arrow" is pointing straight up.
  • 38. Post-surgery head positioning contd • Family member can take a picture of • head position while in the office • reference this picture at home to properly position. • To maintain head position for up to 16 hours per day for 5-8days.
  • 39. When fish egg bubbles form • May be caused by Injection of gas too quickly Needle too deep into the vitreous during injection • Gentle tapping on the eye to make the bubbles coalesce. • positioning the bubbles away from the break for 24 hours allow them to coalesce prevent subretinal gas.
  • 40. Gas migration- Canal of Petit/ anterior hyaloid • May occur if needle not inserted deeply enough needle inserted too anteriorly. • Bubble seen floating behind the lens (“donut sign” or “sausage sign”) • MGT: observe face-down positioning for 24-48hrs gas migrate into the vitreous as it expands
  • 41. Anterior hyaloid gas drainage • If above fails: passive drainage via previous gas insertion site  with a 27-gauge needle on a plungerless 3-cc syringe partially filled with 1cc of sterile water. Reinjection of gas with proper needle placement can be done.
  • 42. Gas migration contd- Gas in the anterior chamber • May be due to lens capsular rent zonular compromise a. Pupillary dilation followed by face-down positioning b. Anterior chamber paracentesis with a 27-gauge needle.
  • 43. Subretinal gas migration • May occur if a. injection site is too close to retina break b. Inappropriately injection under the retina c. Injected with formation of “fish egg" bubbles d. Retinal breaks larger than 1 clock hour • A small amount of subretinal gas can be resorbed without positioning.
  • 44. Subretinal gas migration • Larger bubble requires head positioning: a. Positioning for 24hrs so that bubbles migrate away from the tear. b. Patient lying in a supine position to release subretinal gas into the vitreous by; tilting the head so that the break is at the most superior position gentle scleral depression may release the subretinal gas into the vitreous cavity. • Pars plana vitrectomy and removal of subretinal gas to avoid expansion in the subretinal space and tear.`
  • 45. Intraocular pressure changes post injection • Not a significant problem after the intraocular injection of less than 0.5 mL of gas. • Immediate elevation of intraocular pressure to levels between 30 and 50 mm Hg is common, • Pressure however returns to normal after 90 minutes. • A 0.3% incidence of ischemic optic neuropathy following elevated IOP post PR was reported by Tornambe (1997). • Elevation of IOP beyond normal can be managed with additional anterior chamber paracentesis or topical/systemic IOP-lowering drops.
  • 46. Postoperative/follow up Care • Head positioning for 5-8 days to orient gas bubble at the site of the tear(s). Must position for 16 hours per day, with 15-minutes breaks each hour. • Antibiotic or antibiotic/steroid eyedrops four times per day, usually for 1 week • Examine patient daily until the retina is attached; if the retina is not attached by 2nd day post-op, suspect causes of failure. • New break, missed break, small gas size, patient not positioning adequately may cause early failure • Peripheral inferior subretinal fluid may persist for weeks to months though with a decreasing trend of SRF quantity.
  • 47. Retinal Laser retinopexy • Dilate the pupil • Laser delivery system: Use slit lamp or LIO • Instill topical anaesthetic and position patient. • Laser: Argon blue-green, Nd-YAG Lasers • Duration of 0.1 to 0.2 seconds • spot sizes of 200 to 500 microns • Surround retinal break with 2-3 near- confluent rows of laser. • Supplemental lasers until SRF is completely resolved
  • 48. Postoperative/follow up Care contd • 1st day post-op. • Fifth day or 1week post-op. • 2 weeks post-op. • Monthly follow-up for 3 months. • Every 3 months for a minimum of 6 months. • Management of postoperative complications and additional surgery if indicated.
  • 49. Complications-subconjunctival gas • May be due to incomplete penetration of the sclera by needle leakage of gas from injection site. • Treatment is not required. • Prevent subconjunctival gas by  Proper needle insertion into the vitreous cavity  Immediate placement of cotton-tipped applicator on the injection site after removal of the needle.
  • 50. Complications-Corneal wound dehiscence • Risk factors: previous cornea wound/scars • Full-thickness corneal wounds never regain their original tensile strength. • After intravitreal gas injection, sudden rise in IOP may be up to 180 mm Hg Can stress and rupture corneal scars. • Reduced by slowly injecting a smaller gas volume in patients with risk factors.
  • 51. Complications-Surgical failure due new or missed breaks: New breaks with re-RD reported post PR at a rate of 7- 22%. New or missed breaks occur mostly in the superior 8 clock hour (76% ). Treat with additional gas injection + cryotherapy or laser retinopexy. Inferior quadrants new breaks  with scleral buckling and/or PP vitrectomy.
  • 52. Complications-cataract progression • Not common after pneumatic retinopexy (PR). • No significant difference in lens opacity (operated vs non- operated eyes) at 2 months post PR.(Koch et al,1991) • Minimized cataract Careful placement of the paracentesis needle Avoiding contact between the intraocular gas and the lens (adequate head positioning).
  • 53. Complications-endophthalmitis • Incidence post PR is very low (0.97% cases of staphylococcal endophthalmitis reported by Tornambe and Hilton (1989). • Can be reduced by a. meticulous with the sterile techniques. b. use of 5% povidone iodine solution prior to intraocular injection of gases
  • 54. Complications- Intraocular/ orbital hemorrhage • Intraocular hemorrhage is rare • May be due to injury anterior ciliary vessels (injection site) rupture of scleral vessels (cryotherapy) • Reduce by avoiding injection along the vertical and horizontal meridians (anterior ciliary vessels). Tip of cryoprobe should be allowed to thaw before removal from the ocular surface.
  • 55. Complications- Choroidal detachment (CD) • Not common post PR • Incidence of 3% post PR (Tornambe and Hilton,1989). • Suspect CD if prolonged and severe pain occur shortly after gas injection (gas injected into suprachoroidal space). • Pain: stretching of the ciliary nerves by the gas. • Prevent CD by Avoiding hypotony during paracentesis Reducing excessive cryotherapy
  • 56. Complications-cystoid macular edema • Not common after pneumatic retinopexy. • Risk factors include history of uveitis, prior cataract extraction, and macular detachment. • Can be reduced by avoiding excessive retinopexy • Medical treatment: Topical steroidal and nonsteroidal anti- inflammatory medications.
  • 57. Complications-Macular hole • May be due to vitreomacular traction during the perioperative period. • Expansion of the intraocular gas produces a vitreomacular detachment • Stress of shifting of a large amount of subretinal fluid under the macular. • Treatment is by conventional surgical techniques such as PPV.
  • 58. Epimacular fibrosis and macular pucker • Incidence of 4% of asymptomatic epimacular membrane post PR has been reported. • Minimize risk by avoiding excessive cryotherapy laser retinopexy
  • 59. Complications-Proliferative vitreoretinopathy • Incidence: 9.6-9.8% post PR (9.8% Chen et al, 1988) • No difference in incidence of PVR (cryotherapy versus laser): 9.6%, Tornambe, 1997. • May be caused by Excessive release of RPE cells into the vitreous Gas bubbles • PVR post PR can be treated with PPV and membrane stripping.
  • 60. Complications-Musculoskeletal • Due to consistent head tilt for a prolonged period. • Worse among elderly patients. • They include cervical spine injury, neck muscles and lower back pain, ulnar nerve neuropathy. • They are minor and temporal problems. • PREVENTIVE MEASURES: Use of pillow, cushion, table, desk (with the correct height) • TREATMENT: analgesics, heating pad, muscle relaxants to relieve musculoskeletal discomfort.
  • 61. Pneumatic retinopexy in inferior Breaks • PR ; an adjunctive role for RD with inferior breaks. • Studies involving maintaining an inverted posture for 8 hours following PR Restricted to highly motivated patients. IOP increases significantly in the head-down position (not indicated in glaucomatous eyes)
  • 62. PR in inferior Breaks contd  After PR for inferior retinal breaks post failed scleral buckle; posturing with a combined 10° Trendelenburg position 10° neck hyperextension 10° ocular supraduction • Had 88% success rate (Mansour et al, 2005).
  • 63. Pneumatic retinopexy in inferior Breaks contd • Lateral recumbent posture:77% success rate with inferior detachments. (Hwang et al, 2011) • Use of a temporary buckle in the inferior fornix combined with a face-down position with 5°–10° of neck flexion achieved 88% primary reattachment success. (Cheng et al, 2013). • Previous SB or PPV has been done in majority of these patients  therefore, success in PR as a primary procedure for RD with inferior retinal breaks have only few reported successful cases.
  • 64. Adaptability to our environment • Cost • Complications • Visual prognosis • Skills • Time of presentation
  • 65. Conclusion • Pneumatic retinopexy is currently underutilized despite its effectiveness in selected cases. • Adequate skills in BIO examination, localization of retinal breaks and patient’s motivation to head positioning are essential. • Success involves adequate surgeon’s experience, good patient selection, patience and effective doctor- patient communication.
  • 66. REFERENCES • Lihteh Wu. Pneumatic Retinopexy. Medscape. Updated: Mar 13, 2023 [accessed Aug 12th, 2023]. Available from https://emedicine.medscape.com/article/1844217-overview • Christina Y, Kamjoo S, Amitabh K. Pneumatic Retinopexy. EyeWiki. Jul 26, 2023 2023.[accessed Aug 12th, 2023]. Available from https://eyewiki.aao.org/Pneumatic_Retinopexy. • Wong TY. SNG C, Lim L. The ophthalmology examinations review. Pneumatic retinopexy. 2nd Ed. Singapore: World Scientific Publishing; 2011. p. 189. • Mandelcorn ED, Manusow JS, Mandelcorn MS. Pearls for Performing Pneumatic Retinopexy. Retina specialist. November 13, 2015[ Accessed August 15, 2023]. Available from https://www.retina- specialist.com/article/pearls-for-performing-pneumatic-retinopexy • Stewart S, Chan W. Pneumatic retinopexy: patient selection and specific factors. Clin Ophthalmol. 2018 Mar 16;12:493-502. doi: 10.2147/OPTH.S137607. PMID: 29588570; PMCID: PMC5859893 • Silva RA, Blumenkranz MS. Prophylaxis for Retinal Detachments. AAO. Oct 29, 2013. [Accessed August 15, 2023]. Available from https://www.aao.org/education/munnerlyn-laser-surgery- center/prophylaxis-retinal-detachments
  • 67. REFERENCES contd • Tornambe PE. Pneumatic retinopexy. Surv Ophthalmol. 1988 Jan- Feb;32(4):270-81. doi: 10.1016/0039-6257(88)90175-0. PMID: 3279561. • Chan CK, Lin SG, Nuthi AS, Salib DM. Pneumatic retinopexy for the repair of retinal detachments: a comprehensive review (1986– 2007) Surv Ophthalmol. 2008;53(5):443–478. • Cheng HC, Lee SM, Lee FL, Liu JH, Kuan CH, Lin PK. Short- term external buckling with pneumatic retinopexy for retinal detachment with inferior retinal breaks. Am J Ophthalmol. 2013;155(4):750.e1–756.e1. • Hwang JF, Chen SN, Lin CJ. Treatment of inferior rhegmatogenous retinal detachment by pneumatic retinopexy technique. Retina. 2011;31(2):257–261. • Mansour AM. Pneumatic retinopexy for inferior retinal breaks. Ophthalmology. 2005;112(10):1771–1776.