To present the first detailed assessment of the clinical features of CL-induced subconjunctival hemorrhage and associated risk factors.
Cross-sectional and case-control study of age-matched randomized groups.
A total of 45 CL wearers with subconjunctival hemorrhage aged 18 to 45 years (CL-Hemorrhage group), 200 age-matched healthy control subjects (non-CL group), and 200 age-matched CL wearers (CL group) were enrolled. The conjunctiva was divided into the following 8 equal areas: superior, superior/nasal, nasal, inferior/nasal, inferior, inferior/temporal, temporal, and superior/temporal. The site of hemorrhage, the grade, and other parameters of conjunctivochalasis at 3 locations (nasal, middle, and temporal), and the grade of pinguecula on the nasal or temporal conjunctiva were determined in all subjects.
Typically, subconjunctival hemorrhage affected 1 or 2 regions of the temporal conjunctiva. The grade of conjunctivochalasis and pinguecula was higher in both the affected and unaffected eyes of the CL-Hemorrhage group than the non-CL and CL groups (all P < .00001). The effect of downward gaze or digital pressure on the extent of conjunctivochalasis was more marked in the CL-Hemorrhage group and superficial punctate keratitis was more common (all P < .00001). Multivariate logistic regression analysis of variables revealed that the presence of conjunctivochalasis and pinguecula were associated with an increased risk of CL-induced subconjunctival hemorrhage (all P < .05).
These results suggest that the major risk factors for CL-induced subconjunctival hemorrhage are conjunctivochalasis and pinguecula.
Subconjunctival hemorrhage is a common ocular condition, characterized by the acute appearance of a flat area of bleeding under the conjunctiva. Subconjunctival hemorrhage is a benign disorder with a good visual prognosis. The first study of the risk factors for subconjunctival hemorrhage was the report by Fukuyama and associates, who investigated a large series of consecutive patients. They found that the most common causes of subconjunctival hemorrhage from 1987 to 1988 were minor local trauma, systemic hypertension, and acute conjunctivitis. It is well known that subconjunctival hemorrhage is associated with common systemic vascular disorders such as hypertension and arteriosclerosis, diabetes, trauma, acute hemorrhagic conjunctivitis, and anticoagulant therapy. We have previously reported that conjunctivochalasis and wearing contact lenses (CLs) were associated with the occurrence of subconjunctival hemorrhage.
CLs are currently more popular than glasses because they provide more natural vision and a better cosmetic appearance. However, wearing CLs can cause chronic conjunctival inflammation, conjunctivochalasis, mechanical friction, dehydration, dry eyes, and problems attributable to incompatibility with the lens material. Hence, the number of patients with CL-induced ocular complications has increased. In our previous study on causal factors of subconjunctival hemorrhage, 8 out of 161 patients (5.0%) had contact lens–induced injury. However, there have been no large-scale surveys of subconjunctival hemorrhage associated with wearing CL (CL-subconjunctival hemorrhage). Accordingly, the objectives of the present study were to examine 1) the clinical features of CL-subconjunctival hemorrhage, 2) the risk factors for CL-subconjunctival hemorrhage, and 3) the relation between CL-subconjunctival hemorrhage and conjunctival disorders such as conjunctivochalasis and pinguecula.
CL wearers with subconjunctival hemorrhage were enrolled from among consecutive patients attending our outpatient clinic over a 12-month period. Subconjunctival hemorrhage was diagnosed by slit-lamp examination in 58 CL wearers. Almost all of the patients lived in Tokyo or Kanagawa in Japan. Patients with a history of ocular surgery, punctal occlusion, or trauma were excluded, as were those with infectious conjunctivitis, proptosis, eyelid abnormalities (such as entropion, ectropion, and trichiasis), or systemic conditions that could interfere with interpretation of the study results (such as hypertension, diabetes, hyperlipidemia, thyroid disease, and anticoagulant therapy). Patients over 50 years old were also excluded because their subconjunctival hemorrhage may have been age-related. Consequently, the study population consisted of 45 CL wearers (CL-Hemorrhage group), including 15 men and 30 women aged 31.3 ± 7.5 years (mean ± SD), with an age range of 18 to 45 years ( Tables 1 and 2 , and Figure 1 ). One thousand eight hundred and seventy-three non-CL wearers and 780 CL wearers, who attended our outpatient clinic for eye screening tests, were also selected using the same exclusion criteria as for the CL-Hemorrhage group. Additional exclusion criteria included current or recent use of topical ophthalmic medications or systemic medications such as steroid and anticoagulant drug that could affect eye conditions. These subjects underwent the same clinical examinations as the CL-Hemorrhage group. The 200 age- and gender-matched controls (non-CL group) and 200 CL wearers without subconjunctival hemorrhage (CL group) were randomly selected from the 1873 non-CL wearers and 780 CL wearers, respectively, by random sampling stratified for each decade of age using a random number table computer ( Table 1 ). The non-CL wearers and CL wearers without subconjunctival hemorrhage lived in the same geographic area as the CL wearers with subconjunctival hemorrhage. Hard CLs (HCL) were all rigid gas-permeable lenses.
|Non-CL Wearers (%)||CL Wearers (%)||CL Wearers with Hemorrhage (%)||P Value|
|Number of patients|
|15–20 years||16 (8.0%)||16 (8.0%)||3 (6.6%)||—|
|21–25 years||40 (20.0%)||40 (20.0%)||10 (22.2%)||—|
|26–30 years||40 (20.0%)||40 (20.0%)||8 (17.8%)||—|
|31–35 years||40 (20.0%)||40 (20.0%)||8 (17.8%)||—|
|36–40 years||40 (20.0%)||40 (20.0%)||10 (22.2%)||—|
|41–45 years||24 (12.0%)||24 (12.0%)||6 (13.3%)||—|
|Total||200 (100.0%)||200 (100.0%)||45 (100.0%)|
|Male||95 (47.5%)||81 (40.5%)||15 (33.3%)||NS a|
|Female||105 (52.5%)||119 (59.5%)||30 (66.7%)|
|Age (years)||31.1 ± 7.5||31.1 ± 7.5||31.3 ± 7.5||NS b|
|Spherical equivalent||−2.48 ± 2.36||−5.12 ± 2.36||−5.20 ± 2.78||<.00001 c|
|History of CL use|
|Type worn at examination, HCL/SCL||—||27/173||9/36||NS a|
|Duration of wearing CL (years)||—||9.4 ± 6.8||12.9 ± 6.8||.00125 b|
|Age at first wearing CL (years)||—||21.7 ± 6.6||18.3 ± 5.3||.00025 b|
a χ 2 test of independence, or Fisher exact probability test.
c One-way analysis of variance and Scheffé multiple comparison test.
|Patient No||Age (y)||M/F||R/L||Season a (Month)||Extent b||IOP (mm Hg)||Refraction (Diopters)||Type of CL (Duration of Wearing CL, y)|
|13||25||F||R||11||3||18||−5.50||Conv-SCL (5) → 1D-DSCL (4)|
|14||26||F||L||11||3||19||−5.25||Conv-SCL (5) → 1D-DSCL (5)|
|15||26||M||L||6||2||15||−2.13||Conv-SCL (2) → 1D-DSCL (8)|
|22||31||M||L||11||1||15||−7.75||HCL (6) → 2W-DSCL (7)|
|23||32||F||R||7||1||11||−7.50||HCL (1) → 2W-DSCL (11)|
|26||34||F||R||2||4||14||−7.25||HCL (2) → Conv-SCL (16)|
|27||34||F||R||7||1||15||−11.50||Conv-SCL (9) →2W-DSCL (10)|
|29||35||F||R||12||1||11||−3.00||Conv-SCL (12) → 2W-DSCL (8)|
|33||37||M||L||12||4||14||−2.50||Conv-SCL (5) → HCL (14)|
|36||38||F||R||7||1||16||−10.75||Conv-SCL (7) → 2W-DSCL (14)|
|37||39||F||R||7||2||14||−4.00||HCL (12) → 2W-DSCL (8)|
|41||42||F||L||7||2||20||−3.50||Conv-SCL (18) → 2W-DSCL (8)|
|43||43||F||R||8||1||16||−5.25||HCL (8) → 2W-DSCL (13)|
|44||43||F||L||2||3||16||−2.50||HCL (10) →1D-DSCL (15)|