Glaucoma after Congenital Cataract Surgery 2011. 5. 11 여의도성모병원 안과 조교수 박명희

Developmental and childhood glaucoma Primary glaucoma Secondary glaucoma Congenital open angle glaucoma Autosomal dominant juvenile glaucoma Glaucoma associated with systemic abnormalities Axenfeld-Rieger syndrome Congenital rubella Chromosomal disorders Glaucoma associated with ocular abnormalities Aniridia Microcornea syndromes Peters syndrome PPMD Sclerocornea Traumatic glaucoma Glaucoma secondary to intraocular neoplasm Uveitic glaucoma Lens-induced glaucoma Steroid induced glaucoma Neovascular glaucoma Secondary angle-closure glaucoma Glaucoma with increased episcleral venous pressure Glaucoma secondary to intraocular infections Glaucoma after congenital cataract surgery

Developmental and childhood glaucoma Of all pediatric glaucomas in a tertiary-referral setting, aphakic glaucoma was responsible for 20% of cases, second only to primary congenital glaucoma. (Taylor et al., J AAPOS 1999) Among 1492 hospitalized pediatric glaucoma patients in Beijing Tongren Hospital from 2002 to 2008, congenital glaucoma was 46.07%, traumatic glaucoma was 12.13%, and aphakic glaucoma was 9.19%. (Qiao et al., Chin Med J 2009)

Incidence of glaucoma after pediatric cataract surgery : Approximate frequency of 10-25% commonly cited Of 392 consecutive childhood cataract aspiration procedures, chronic glaucoma was found in 6.1% of the eyes during mean 5.5 years follow-up. Coexisting ocular anomalies and retained lens cortex increased the risk for this complication. (Chrousos et al., Ophthalmology, 1984) After mean 9.6 years follow-up of 137 aphakic eyes, 12% of the eyes developed glaucoma. (Magnusun et al., Acta Ophthalmol Scand 2000) At a median of 15.1 years after surgery, a majority of the subjects had glaucoma or ocular hypertension (ie, 59%; 37/63). 19% (12/63) had glaucoma (5/22 with bilateral cataracts and 7/41 with unilateral cataracts). Approximately half (7/12) had developed glaucoma during the first 5-year observational period and the remainder (5/12) developed it during the following observational period. (Egbert et al., J AAPOS 2006) At mean follow-up 9.0 years after cataract surgery, glaucoma developed in 118 of 570 patients' eyes (21%). (Rabiah, AJO 2004) Of 269 aphakic eyes, 62 (23%) eyes were diagnosed with glaucoma(36 of 130 patients, 27.7%) an average of 59 months (Al-Dahmash et al., Eye & contact lens, 2010). 2 out of 20 pediatric aphakic patients (10%) developed glaucoma after 40.02 months follow-up. (Kim et al., KJO 2008)

Approximately 20% (or more Approximately 20% (or more!) of children who had a cataract extraction will at some point of their lifetime develop glaucoma.

Pediatric cataract 1 per every 2000 births Cause Idiopathic (m/c) Autosomal dominant > autosomal recessive > sex chromosome related Associated with hereditary, metabolic, systemic disease Intrauterine infection (TORCHS) Associated with ocular abnormalities Aniridia Anterior segment dysgenesis Microphthalmia PHPV Posterior lenticonus Traumatic

Pediatric cataract surgery Corneal incision Side port paracentesis Limbal incision Anterior capsulectomy CCC Vitreous-cutting instrument Lens aspiration Posterior capsulectomy Anterior vitrectomy with two port system (±) PC-IOL implantation with optic capture Corneal suture

Etiology of aphakic glaucoma Lens debirs or uveitic blockade of trabeculum Pupillary blockade Pigment dispersion Peripheral anterior synechiae / Trabecular damage Chronic open-angle

Etiology of aphakic glaucoma

Risk factors for developing of chronic open angle glaucoma Chen et al., JPOS 2006 Early age of cataract surgery (before 4 months) Postoperative complications Multiple procedure Small corneas (<10mm) Family history of aphakia Congenital rubella syndrome No IOL ? Khan et al., J AAPOS 2008

Hypothesis of pathophysiological mechanism of chronic open angle aphakic glaucoma chronic trabeculitis from postoperative inflammation blockade from retained lens material chemical factors from the vitreous (Phelps & Arafat 1993).

Hypothesis of pathophysiological mechanism of chronic open angle aphakic glaucoma A manifestation of a single ocular syndrome with an abnormal anterior segment The defect responsible for producing the cataract may also affect aqueous outflow in the angle, causing open angle glaucoma (Phelps & Arafat 1993). Early lensectomy may interfere with maturation of the trabecular meshwork. Further damage by surgical trauma and exposure to the vitreous and high-dose steroid Kang et al., KJO 2006

Effect of IOL on the development of chronic open-angle glaucoma Asrani et al. (J AAPOS 1999) Comparison of the incidence of open-angle glaucoma in the two large groups of pseudophakic and aphakic pediatric patients a reduced incidence in the pseudophakic eyes. Patients in the study routinely had IOLs implanted when the corneal diameter was > 10 mm. 1/377 pseudophakic Eyes during 3.9 years f/u 14/124 aphakic eyes during 7.2 years f/u

Effect of IOL on the development of chronic open-angle glaucoma 2 theories for the lower incidence in pseudophakic eyes (Asrani et al. J AAPOS 1999) Chemical theory In aphakia, a vitreous chemical component (toxic to the trabecular meshwork) may have access to the trabecular meshwork, resulting in damage. This is prevented in pseudophakic eyes by the presence of an implant that forms a barrier to the vitreous. Mechanical theory The support to trabecular meshwork is lost in aphakia. A disorganization or collapse of the TM results in its diminished function as a filter. Placement of a PC IOL might minimize this loss of support.

No relationship? Cataract surgery at an early age (< 4.5 months) are risk for the development of glaucoma c/s an IOL implant (Trivedi et al., J AAPOS 2006)

How to find a glaucoma? IOP Corneal cloudiness Corneal diameter Refractional change: less hyperopic Axial length Optic nerve

Examination of children Office examination A complete ocular examination can be performed in the office in children older than 5 years of age and in some children as young as 3 with some training. Many children after age 5 can undergo kinetic Goldmann VF testing with the assistance of a parent. By the age of 8-10 years, some children can cooperate for a full quantitative visual field examination. For an infant, a careful examination can be performed over a bottle or breast milk. Chloral hydrate (100mg/kg of BW, maximum dose of 3g) can be given if necessary and does not affect IOP readings.

Examination of children Examination under anesthesia (EUA) General anesthesia is usually required for a thorough examination of children under the age of 5. Most of general anesthetics lower IOP to variable amounts and at variable times after administration. IV Ketamine may raise IOP slightly. Succinylcholine and endotracheal intubation significantly elevate IOP.

Examination of children Examination under anesthesia (EUA) The sequential component of the EUA IOP Corneal thickness and diameters Goniosocpy Ophthalmoscopy Axial length UBM Cycloplegic retinoscopy

IOP among normal awake children using different tonometers Age Pulsair (SD) Pensiero et al., JPOS 1992 Perkins (SD) Jaafar et al., JPOS 1993 Pneumatonometer (SD) Spierer et al., 1994 Premature (26-37 weeks) 10.2 18.3 - 0-1 yr 10.6 (3.1) 4.6 (0.5) 14.5 (0.5) 1-2 yrs 12.0 (3.2) 4.9 (0.5) 14.6 (0.6) 2-3 yrs 12.6 (1.5) 5.8 (1.0) 15.3 (1.4) 3-4 yrs 13.7 (2.1) 6.4 (1.8) 14.5 (0.9) 4-5 yrs 14.4 (2.0) 7.9 (1.3) 14.8 (2.0) 5-6 yrs 6-7 yrs 14.2 (2.3) 7-8 yrs 14.0 (2.5) 8-9 yrs 14.3 (1.7) 9-10 yrs 14.0 (2.7) 15-16 yrs 15.2 (2.4) 13.2 16.42 (2.2)

Corneal measurements: diameter A good baseline measurement is required for Initial diagnosis Detection of subsequent corneal enlargement under age 3 Age Corneal diameter (horizontal, in mm) Normal Suspicious for Possible Glaucoma Birth – 6 months 9.5-11.5 >12 1-2 years 10-12 >12.5 Older child =<12 >13

Corneal measurements: diameter Corneal diameter measurement Horizontal (3 to 9 o’clock) and Vertical (6 to 12 o’clock) From white to white Co-examination for corneal haziness and tears of Descemet’s membrane (Haab striae) is needed.

Axial lengths among normal eyes and eyes suspicious for glaucoma Age Axial length (mm) Normal Suspicious for Possible Glaucoma Newborns 16-17 >20 1 year 20.1 >22.5 2 years 21.3 >23 3 years 22.1 >24 >3 years 23 >25 Sampaolesi et al., Arch Ophtahlmol 1982

Corneal measurements: central thickness CCT The clinical effect of CCT measures on IOP in children is similar to that seen in adults. In congenital glaucoma, CCT is thinner in glaucomatous eyes and positively correlated with their larger corneal diameters and longer axial lengths. CCT in children without glaucoma Hussein et al., Am J Ophthalmol 2004

Effect of IOL implantation on CCT In the absence of factors known to affect CCT, CCT is similar in eyes with congenital cataract and normal controls and increases after cataract surgery (Muir et al., AJO 2007)

Effect of IOL implantation on CCT CCT in children with cataracts increases after cataract surgery while the fellow eye remains stable. This increase seems to occur early after surgery, likely remaining stable thereafter, though glaucoma can accentuate the increase. (Lim et al., AJO 2011)

CCT in various kinds of pediatric glaucoma Patients with aphakic glaucoma are different from those with congenital glaucoma. Lopes et al., JPOS 2007 Tai et al., J glaucoma 2006

Ophthalmoscopy Fundus examination is challenging in many aphakic/pseudophakic children because of small pupil, PCO, persistent fetal vasculature, and nystagmus. But glaucoma should not be diagnosed by single high IOP itself unless extreme. Direct ophthalmoscopy can be used during EUA. C/D >0.3 is rare in healthy infants. With successful control of the IOP, the cup will either remain stable or its size will decrease. Concentric enlarging of cupping is more common than vertical notching in children.

Treatment of pediatric aphakic glaucoma Medication Surgery Goniotomy and/or Trabeculotomy Variable success rate reported (16~57%) Multiple procedures may be needed Trabeculectomy c MMC soaking Glaucoma Shunt Devices Trans-scleral diode laser cyclodestruction

Pediatric aphakic glaucoma Second most common type of pediatric glaucoma Approximately 20% of incidence during lifetime after congenital cataract surgery Chronic open angle glaucoma is more common than acute angle closure glaucoma. If any risk factor is accompanied, careful lifetime examination is necessary. IOL implantation may play a protective role in glaucoma development. CCT may change after cataract surgery and thus influence on IOP measures. Elevated IOP by itself, unless extreme, is insufficient to conform the diagnosis of glaucoma.

Variables to consider when assessing a child’s IOP The child’s age The patient’s level of activity or sedation Effects of anesthetics Corneal thickness and health Diurnal variations Measuring instrument

University of California, San Francisco (UCSF), Beckman Vision Center, Glaucoma Service Mentor: Robert L Stamper, M.D. Professor of Ophthalmology Director of the Glaucoma Clinic the chairman of the Prevent Blindness Northern California

University of California, San Francisco (UCSF), Beckman Vision Center, Glaucoma Service