To examine the development and management of glaucoma in patients with ocular chemical burns.
Retrospective, observational case series.
setting: University of Washington Eye Clinics. patient population: Twenty-nine eyes (18 patients) with ocular chemical burns seen between 1997 and 2010 with a minimum of 3 months of follow-up. observation procedure: Eyes were graded using the Roper-Hall scale. main outcome measures: Long-term use of glaucoma medications (3 months or more) and need for glaucoma surgery.
The mean age was 45 ± 17 years, with a mean follow-up of 75 ± 47 months (median, 66 months). Roper-Hall grade III or IV eyes (n = 20) had significantly higher intraocular pressure at presentation (35.9 vs 16.4 mm Hg; P = .001) and over follow-up were more likely to require long-term glaucoma medications ( P = .003) or to undergo glaucoma surgery ( P = .016) than Roper-Hall grade I or II eyes. Thirteen eyes (12 Roper-Hall grade III or IV) underwent glaucoma surgery. Eight eyes underwent glaucoma tube implant surgery; 4 required at least 1 revision. Seven eyes underwent diode laser cyclophotocoagulation; 4 required repeat treatment. Most (89%) eyes had controlled intraocular pressure at the last follow-up. However, 76% of eyes with visual acuity of 20/200 or worse at initial evaluation did not have improved vision at the last follow-up.
Eyes with Roper-Hall grade III or IV ocular chemical burns were more likely to have glaucoma and to require surgery for it. Outcomes of glaucoma management generally were good, although tube implant surgeries often had complications requiring revision.
Chemical burns constitute between 8% and 18% of ocular trauma. Most victims are young males between the ages of 16 and 45 years. Injuries are often work related, and nearly 90% of injuries occur as a result of accidents. Alkali burns are more common than acid burns and are more severe. Many prognostic factors have been examined in evaluating visual recovery after ocular chemical burns, including pH and concentration of the chemical, duration of exposure, corneal stromal whitening, and the extent of limbal ischemia. However, few studies have examined glaucoma after ocular chemical burns. The purpose of this study is to investigate the risk of, and risk factors for, development of glaucoma after ocular exposure to acid and alkali chemical agents and the outcomes of management for glaucoma in these cases.
We reviewed patients seen between 1997 and 2010 at the Eye Clinics of the University of Washington (University of Washington Medical Center and Harborview Medical Center). Patients were identified by International Classification of Disease, Ninth Edition, code search for ocular burns (940.0 through 940.5). Patients with ocular chemical burns with at least 3 months of follow-up were included in the study. Although glaucoma usually is assessed though evaluation of the optic nerve and visual field, because of the type of injury and the resulting poor corneal clarity, most patients did not have optic nerve findings recorded or visual field testing performed during follow-up. Therefore, we defined glaucoma as intraocular pressure (IOP) of more than 21 mm Hg and requiring treatment during management of ocular chemical burns.
Clinical data collected included type of chemical burn, ocular pH, demographic data (age, sex, race), visual acuity, IOP, glaucoma medications, and examination findings and procedures performed at presentation and over follow-up. Long-term medication use was defined as use of glaucoma medications at or beyond 3 months after injury.
Roper-Hall classification was used, in some cases retrospectively, to grade the severity of the burns. In brief, Roper-Hall grade I burns indicate corneal epithelial damage without limbal ischemia. Grade II burns indicate corneal haze with iris details visible and less than one third limbal ischemia. Grade III burns indicate total epithelial loss, stromal haze with iris details obscured, and one third to one half limbal ischemia. Grade IV burns indicate dense stromal haze with the iris and pupil obscured, and more than one half limbal ischemia. Eyes also were stratified into 2 groups based on presenting visual acuity: Snellen acuity of better than 20/200 and Snellen acuity of 20/200 or worse. Data were entered into a spreadsheet (SPSS software version 16.0 for Mac; SPSS, Inc, Chicago, Illinois, USA). Statistical analysis was performed with chi-square and Fisher exact testing and independent-samples, 2-tail t test.
Twenty-nine eyes (18 patients) with ocular chemical burns were identified and met inclusion criteria ( Table 1 ). The mean patient age was 45.4 ± 16.7 years (range, 19 to 77 years), and mean follow-up was 75 ± 47 months (median, 66 months; range, 10 to 157 months). Most patients were male (15/18; 83%) and white (15/18; 83%). Twenty-four eyes (83%) had alkali burns with a mean pH of 9.38, whereas 5 eyes (17%) had acid burns. Among eyes with alkali burns, 68% (15/22) had visual acuity of 20/200 or worse, compared with 60% (3/5) in eyes with acid burns. In 2 eyes (7%) with alkali burns, the initial visual acuity was unknown because the patient was intubated at the time of initial evaluation. In 1 eye (3.4%), the initial visual acuity was no light perception because of prior damage from long-standing angle-recession glaucoma, which was well controlled with medications before the chemical injury; this eye was not included in evaluation of visual acuity during follow-up. Four eyes (14%; all with initial visual acuity of 20/200 or worse; 2 patients) were injured in accidents involving suspected methamphetamine manufacture.
|Eye No.||Age (years)||Type of Burn||Follow-up (months)||Roper-Hall Grade||Initial Visual Acuity||Initial IOP (mm Hg)||Final Visual Acuity||Final IOP (mm Hg)||IOP Medications (> 3 months)||Glaucoma Surgery Type||No. of Months to First Glaucoma Surgery||Corneal Surgery Type|
|1||28||Alkali a||98||4||20/400||42||20/80||20||Yes||Baerveldt, revision × 1||26||KPro I, KPro II|
|3||51||Alkali||151||4||20/200||23||20/60||5||Yes||Ahmed, removal, cyclocryotherapy||23||KPro II|
|4||51||Alkali||151||3||20/80||15||LP||10||Yes||ECP, CPC||105||PKP × 3, KPro I|
|8||33||Alkali||53||4||HM||43||Enucleation||43||Yes||PKP × 2|
|11||24||Acid||18||4||20/400||25||HM||6||Yes||CPC, Baerveldt, revision × 1||3||PKP × 2|
|12||45||Alkali||103||4||HM||NR||Enucleation||25||Yes||Tube (type unknown)||60||PKP × 2, KPro I|
|13||25||Alkali||10||3||NR||21||CF||6||Yes||CPC × 3||3||PKP|
|20||44||Alkali||157||3||LP||60||20/40||10||Yes||Ahmed + CPC||10||KPro II|
|23||70||Alkali||16||4||HM||21||20/200||20||Yes||PKP, KPro I|
|26||46||Alkali||109||4||20/400||40||HM||15||Yes||Baerveldt × 2, revision × 4||4||PKP, KPro I|
|28||52||Alkali||97||3||20/400||47||HM||20||Yes||CPC × 2||12||Declined|
|29||52||Alkali||97||4||20/400||87||LP||20||Yes||CPC × 3||11||Declined|
Roper-Hall classification resulted in 5 eyes (17.2%) with grade I ocular chemical burns, 4 eyes (13.8%) with grade II ocular chemical burns, 9 eyes (31.0%) with grade III ocular chemical burns, and 11 eyes (37.9%) with grade IV ocular chemical burns. One eye (3.4%) was enucleated after 10 days because of endophthalmitis after corneal perforation and was not included in the analysis of glaucoma development or treatment.
Higher Roper-Hall grade was associated significantly with initial visual acuity of 20/200 or worse. Higher Roper-Hall grade also was associated with worse initial visual acuity ( P = .016, analysis of variance), but not with higher initial IOP ( P = .055, analysis of variance), unless Roper-Hall grade III and IV eyes were combined and compared with Roper-Hall grade I and II eyes ( P = .001; Table 2 ). Higher Roper-Hall grade also was associated significantly with any glaucoma medication use ( P < .001), long-term glaucoma medication use ( P = .010), need for any ophthalmic surgery ( P = .003), and visual acuity of 20/200 or worse at final visit ( P = .020). Most eyes that required long-term glaucoma medication use had elevated IOP by the first week after injury (15/18 eyes; 83%).
|Findings||Roper-Hall Grade I/II||Roper-Hall Grade III/IV||P Value|
|Age (years)||54 ± 20||41 ± 14||.153 a|
|Follow-up (mos)||73 ± 33||75 ± 53||.895 a|
|Chemical: alkali/acid (eyes)||7/2||17/3||.633 b|
|Eyes requiring glaucoma medication|
|Initial||1/9 (11%)||18/20 (90%)||< .001 b|
|Long term||2/9 (22%)||16/19 (84%)||.003 b|
|No. of long-term medications||0.4 ± 1.0||1.8 ± 1.4||.018 a|
|Glaucoma surgery (eyes)||1/9 (11%)||12/19 (63%)||.016 b|
|Other surgery (eyes)||1/9 (11%)||17/20 (85%)||< .001 b|
|logMAR||0.46 ± 0.34||1.90 ± 1.18||< .001 a|
|> 20/200 (eyes)||7/9 (77%)||2/19 (11%)||.001 b|
|logMAR||0.61 ± 0.96||2.49 ± 1.72||.001 a|
|> 20/200||7/9 (77%)||5/19 (26%)||.014 b|
|Intraocular pressure (mm Hg)|
|Initial||17.1 ± 7.3||35.6 ± 18.8||.001 a|
|Final||16.2 ± 5.0||14.5 ± 9.2||.601 a|