Cataract surgery, despite being an anterior segment procedure, can sometimes cause posterior segment complications. Hence, the subject matter remains an important topic for expert discussion. At the recently held joint EURETINA-ESCRS 2018 Congress in Vienna, Austria, a diverse panel of vitreoretinal specialists connected with an enthusiastic crowd in a dynamic discussion of the posterior segment complications of cataract surgery.
Based on presentation by Dr. Bhuvan Chanana, senior consultant, vitreoretina and uvea specialist, Bharti Eye Hospital and Foundation, India, on “Management of Dropped IOL and Nucleus” and “Endophthalmitis: Early Detection, Differentiation from Sterile Reaction and Management”.
Management of intraocular lens (IOL) dislocation, according to Dr. Bhuvan Chanana, has been reported to occur in 0.2-1.8% of patients after cataract surgery. He stressed that the key to management of such complications is to remain calm and to avoid over manipulation in order to prevent extension of the capsular tear and the development of further complications.
Optimal times for intervention include intraoperatively and up to 2 weeks postoperatively when inflammation and corneal edema has subsided. Nuclear fragments less than 20% may not cause significant inflammation and may be reabsorbed spontaneously.
The use of viscoelastics in the prevention of anterior migration of the vitreous and the use of sutures to keep incisions watertight to prevent postoperative complications such as hypotony or endophthalmitis are recommended. Attempts to follow the lens fragments by IOL fishing should not be pursued as these procedures may lead to complications like retinal breaks, giant retinal tears (GRT) and even retinal detachment (RD).
Surgical management like a 23-25G vitrectomy with removal of all vitreous adhesions around the lens fragments to avoid traction may be considered. Soft lens matter may be removed with cutter, but harder fragments are to be removed with a fragmatome.
If handled correctly, a dropped nucleus or IOLs during cataract surgery in most cases do not lead to any serious complications if managed correctly during cataract operation and operated by VR specialist using pars plana vitrectomy and removal.
Endophthalmitis, as discussed additionally by Dr. Chanana in the same symposium, is a common complication of cataract surgery. It is defined as an intraocular inflammation predominantly involving the vitreous cavity (leading to exudation in the vitreous cavity) and anterior chamber commonly as a result of intraocular colonization by microorganisms. In advanced cases, contiguous ocular structures such as the retina or choroid may be involved.
It is very important to differentiate endophthalmitis from an exaggerated reaction as the management of such a case is very different, and a delay in the diagnosis may result in grave outcomes.
An important prophylactic step recommended to decrease the incidence of postoperative endophthalmitis is 5% povidone iodine cleaning for at least three minutes. Single use instruments (including single use tubing) are always preferred. Data currently shows that there is no reduction in the risk of endophthalmitis with preoperative cutting of eye lashes and that taping back of the eyelashes instead in order to exclude them from the surgical field is recommended.
Based on presentation by Dr. Atchara Amphornphruet, Rajavithi Hospital in Rangsit University, Bangkok, Thailand, on “Cystoid Macular Edema: When and How to Treat?”.
“Pseudophakic cystoid macular edema (PCME) is a common complication following cataract surgery,” noted Dr. Atchara Amphornphruet. It has a clinical incidence ranging as high as 2-12% in extracapsular cataract extraction (ECCE) and as low as 0.1-2.35% with the use of phacoemulsification. PCME remains an important cause of suboptimal postoperative vision.
Although acute cases of PCME may spontaneously resolve without intervention within a span of 3-4 months, it may also progress to a chronic stage that affects vision. The incidence of PCME has however decreased over the years with the development of less invasive and traumatic cataract surgery techniques.
Topical NSAIDs remain the mainstay in prevention and the management of PCME with topical, periocular and intraocular corticosteroids serving as a useful adjunct. Surgical intervention can be effective in certain cases and there is currently no standard algorithm for the prevention and treatment of PCME highlighting the need for more prospective randomized clinical trials.
Based on presentation by Dr. Heinrich Heimann, Royal Liverpool University Hospital, United Kingdom, on “Retinal Detachment in Mismanaged Cataract Surgery: Prevention, Etiology and Management”.
In standardized phacoemulsification surgery, the first year incidence of retinal detachment (RD) was relatively low at 0.16 – the 8-year cumulated incidence rose to 0.93 per eye. There was also a 4-fold increased risk when the fellow non-operated eye was used as a reference.
Posterior capsule (PC) rupture with myopia was found to be the most important risk factor while PC rupture was found to be the most important modifiable risk factor in pseudophakic retinal detachment (with vitreous loss being an important feature and increased difficulty with the presence of nuclear fragments in the vitreous).
Dr. Heimann shared some tips with the audience on phacoemulsification. He stressed on the importance of having a good view of the operative field and mastering the slowest possible rhexis. Hydrodissection of the nucleus and complete separation of pieces decrease surgical complexity.
Based on presentation by Dr. Martin Zinkernagel, Department of Ophthalmology and Department of Clinical Research, Bern University Hospital, Switzerland, on “Inadvertent Globe Perforation during Local Anaesthesia for Cataract Surgery and its Management”.
A rare yet devastating complication during peri- or retrobulbar block is globe perforation or penetration, which has an incidence of 1:16000 and 1:10000, respectively.
Dr. Martin Zinkernagel highlighted that preventive strategies included the use of topical anaesthesia or a sub-tenon block, blunt needles and a technique which involves avoiding the globe by going transconjunctivally rather than through the skin.
An early diagnosis followed by proper management is key to achieving the best possible outcome. Anaesthetic effects on the retina are usually reversible and an early vitrectomy for vitreous hemorrhage before retinal detachment develops is recommended.
Based on presentation by Dr. V. Chaikitmongkol, Department of Ophthalmology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand, on “Expulsive Hemorrhage: Early Detection and Management”.
Expulsive hemorrhage remains one of the most frightening complications that can occur during intraocular cataract surgery. It is an explosive accumulation of blood from the suprachoroidal space leading to an expulsion of intraocular contents and permanent vision loss.
In order to decrease the risk of expulsive hemorrhage, sudden drops in intraocular pressure (IOP) should be avoided and the surgeon should always be alert for early signs of suprachoroidal hemorrhage. Extra precautions are necessary in patients at risk of coughing during surgery and or those who have underlying risk factors for expulsive hemorrhage.
Dr. Chaikitmongkol emphasized that the key to preserving an eye in such a scenario would rely on early detection and prompt action. Primary surgical management would involve immediate closure of wound, creation of anterior pressure, IV medications and positioning of the patient in an extreme reverse Trendelenburg position to reduce central venous pressure. Primary drainage is controversial and is not recommended as it may be unsuccessful due to clotting of the hemorrhagic blood in the suprachoroidal space and may reverse the tamponade effect which would result in additional bleeding.
Editor’s Note: PIE Magazine Issue 07 was distributed at the Joint EURETINA-ESCRS 2018 Congress, held in Vienna, Austria. Reporting for this story, “Posterior Segment Complications of Cataract Surgery”, also took place at EURETINA-ESCRS 2018.
