Validation of grading scales for contact lens complications

The validity of use of two artist-rendered and two photographic sets of grading scales (grading 'systems') designed for gauging the severity of contact lens-related ocular pathology was assessed in terms of precision and reliability. Thirteen observers each graded 30 images--by interpolation or extrapolation to the nearest 0.1 increment--of each of the three contact lens complications (corneal staining, conjunctival redness and papillary conjunctivitis) that were common to all four grading systems. This entire procedure was repeated approximately two weeks later, yielding a total data base comprising of 9360 individual grading estimates. Analysis of variance revealed statistically significant differences in both precision and reliability between systems, observers and conditions (p < 0.03 for system reliability; p = 0.0001 for all other combinations). The artist-rendered systems generally afforded lower grading estimates and better grading reliability than the photographic systems. Corneal staining could be graded less reliably than conjunctival redness and papillary conjunctivitis. Grading reliability was generally unaffected by the severity of the condition being assessed. Notwithstanding the above differences, all four grading systems are validated for clinical use and practitioners can initially expect to use these systems with average 95% confidence limits of +/- 1.2 grading scale units (observer range +/- 0.7 to +/- 2.5 grading scale units). In view of the significant between-system differences revealed in this study, it is advisable to consistently use the same grading system. It may be possible to reduce between-observer differences by applying personalised correction factors to normalise grading estimates.     

The comparative clinical performance of a new polyhexamethylene biguanide- vs a polyquad-based contact lens care regime with two silicone hydrogel contact lenses

PURPOSE: To compare the clinical performance of a new polyhexamethylene-biguanide (PHMB)- vs a polyquad-based contact lens care regime with two silicone hydrogel contact lenses. METHODS: This study was a randomised, controlled and investigator-masked (to the lens regimen) clinical study where the clinical performance of two multipurpose contact lens solutions was compared at a single site. Forty-one existing contact lens wearers were recruited and fitted randomly with either galyfilcon A or lotrafilcon A contact lenses. Subjects wore the same lens type for a period of 2 months but used a different care regime (PHMB- and polyquad-based) in a crossover manner, each for a period of 1 month. The primary outcome measure was the difference in corneal staining. Corneal staining was graded in five different locations: central, superior, inferior, temporal and nasal. Measurements of conjunctival redness, limbal redness, conjunctival staining and papillary conjunctivitis were also carried out throughout the study. Biomicroscopic measures were graded using the Efron grading scales. A variety of symptoms were also measured using a visual analogue scale. RESULTS: There was no statistically significant difference in overall corneal staining between lens types (p = 0.16) or care regimens (p = 0.60). Central corneal staining was significantly greater for the polyquad-based care regimen when compared with the PHMB-based care regimen (p = 0.04). Lotrafilcon A lenses showed greater superior corneal staining (p = 0.0004) and papillary conjunctivitis (p = 0.02), and lower comfort on insertion (p = 0.03) when compared with galyfilcon A lenses regardless of the care regime used. There were no statistically significant differences in the other biomicrosopic signs and symptoms between the lens types and the care regimes. CONCLUSIONS: Both care regimes performed in a similar clinical manner and are valid for use with the two silicone hydrogel contact lenses used in this study.     

The influence of lens conditioning on signs and symptoms with new hydrogel contact lenses

Background: Daily disposable contact lenses are considered to be the pinnacle of safe contact lens wear, yet it has been suggested that it takes some period of wear for the lens surface to reach optimal compatibility with the ocular surface. This study assesses the influence of brief treatment with a conditioning drop on the ocular response to new contact lenses over a single day of wear. Methods: The study was a single‐masked, paired (contralateral) comparison of the signs and symptoms with wear of new Acuvue 2 contact lenses pretreated with a conditioning agent containing carboxymethylcellulose (carmellose, CMC) against new lenses inserted directly from the blister pack. Sixty‐one subjects participated in the study, of whom 59 were considered eligible for data analysis. Subjects were also divided into symptomatic and asymptomatic lens wearers based on their overall comfort level in lens wear. Symptoms and signs were recorded at lens delivery and following eight hours of wear. Results: A set of slitlamp signs, comprising corneal staining (p < 0.05), limbal redness (p < 0.05), bulbar conjunctival hyperaemia (p < 0.05), bulbar conjunctival staining (p < 0.01) and palpebral conjunctival redness (p < 0.05) showed small but statistically significant (p < 0.05) end‐ofday mean values in favour of the lens that was conditioned with the rewetting agent. These data were supported by the proportion of subjects showing lower gradings with conditioned lenses versus unconditioned lenses, as follows: corneal staining (35 per cent versus 12 per cent, p <0.05), limbal redness (43 per cent versus 22 per cent, p < 0.05), bulbar conjunctival hyperaemia (50 per cent versus 15 per cent, p < 0.05), bulbar conjunctival staining (46 per cent versus 30 per cent, p < 0.1) and palpebral conjunctival hyperaemia (28 per cent versus 17 per cent, NS). For those subjects reporting symptoms with lens wear (n = 12), there was a statistically significant (p < 0.05) preference in terms of comfort as a result of preconditioning. Conclusions: The results of the investigation suggest that use of a conditioning agent can provide a more physiologically suitable environment for a new lens, thereby reducing the clinical signs associated with lens discomfort. The protocol used here, which is based on a statistical paradigm using standard pictorial grading scales, allows high sensitivity in detecting small changes in ocular parameters.     

软接触镜并发症临床分析

统计分析软接触镜致眼部并发症434例(737眼),其中急性红眼反应162例(37.3%),滤泡性结膜炎或巨乳头状结膜炎54例(12.4%),角膜浸润147例(33.9%),角膜溃疡62例(14.3%),角膜新生血管2例(0.5%)及角膜上皮片状损伤7例(1.6%)。统计结果显示长戴型软接触镜比日戴型具有更大的危险性。     

Comparison of the performance of 6- or 30-night extended wear schedules with silicone hydrogel lenses over 3 years.

AIM: To compare the clinical performance of silicone hydrogel lenses worn for 6- or 30-nights, with monthly replacement, for 3 years. METHODS: In this 3-year prospective clinical trial, 161 subjects were enrolled and 154 commenced extended wear. Clinical performance was assessed by comparing discontinuations and lens surface characteristics (front surface deposits, lens wettability, number of mucin balls), lens fitting performance (primary gaze movement, lens tightness), and physiologic parameters (limbal and bulbar redness, corneal and conjunctival staining, microcysts) and subjective parameters (ratings of comfort and vision) between groups. RESULTS: Eighty-eight subjects remained in the study after 36 months. There were no differences in the probability of subjects surviving in either group, and the major cause of lens-related discontinuation in both groups was contact lens-induced papillary conjunctivitis. There were no clinically important differences in performance between wear schedules. CONCLUSION: The long-term clinical performance of silicone hydrogels worn for 6- or 30-nights continuously was similar. Clinical markers of hypoxia were low in both groups, and the 6-night wear schedule was not superior to the 30-night wear schedule with regard to preventing lens spoilage, improving corneal physiology, or subjective symptoms of comfort and vision.     

Short-term physiologic response in neophyte subjects fitted with hydrogel and silicone hydrogel contact lenses.

PURPOSE: To investigate the short-term physiologic response to three soft lens materials with different oxygen permeability characteristics. METHODS: Forty-three neophytes were randomly prescribed Acuvue 2, Acuvue Advance (Johnson & Johnson Vision Care), or Focus Night & Day (CIBA Vision) for 4 weeks on a daily-wear basis. A further 19 subjects did not wear lenses (control). Experimental and control subjects were examined 2 and 4 weeks after dispensing. Ocular physiologic response was measured with a slitlamp biomicroscope in a strictly masked fashion. RESULTS: Limbal redness increased in the Acuvue 2 group compared with the other two groups. Conjunctival redness increased more in the Acuvue 2 group than in the Acuvue Advance group. More conjunctival staining was seen with the Acuvue Advance and Focus Night & Day groups compared with the Acuvue 2 group. Increased scores for papillary conjunctivitis were seen in the Focus Night & Day group compared with the Acuvue Advance group. CONCLUSIONS: The reduced level of limbal redness seen with the Acuvue Advance and Focus Night & Day groups suggests that these lenses provide more oxygen to the ocular surface than the Acuvue 2 lens to a degree that can be observed clinically. The conjunctival staining response was similar for the Acuvue Advance and Focus Night & Day groups. The results for the Acuvue Advance and Focus Night & Day groups for papillary conjunctivitis may reflect differences in their material and surface properties.     

Delayed tear clearance in contact lens associated papillary conjunctivitis.

PURPOSE. To study the tear film clearance in contact lens associated papillary conjunctivitis patients. METHODS. Fifty-eight daily-wear soft contact lens wearers completed a questionnaire regarding a survey of their contact lens usage and subjective symptoms. They were grouped according to the size of conjunctival papillae, namely PC1 with no papillae, PC2 with papillae of less than 0.3 mm, and PC3 with papillae of 0.3-1.0 mm in diameter. Tear film breakup time and fluorescein clearance tests were performed. RESULTS. There was a median of 1, 2, and 3 subjective symptoms in PC1, PC2, and PC3 groups respectively (p < 0.001). Patients with larger papillae on their upper tarsus had more subjective symptoms such as burning sensation, discharge, limbal injection, foreign body sensation and dryness sensation (p = 0.018, 0.001, 0.004, 0.005, and 0.036 respectively). They also had shorter tear film breakup time (p = 0.05), delayed tear clearance (p = 0.002) and more corneal neovascularization (p < 0.001). Patients having delayed tear clearance test tended to have more subjective symptoms (p = 0.004) and larger papillae on upper tarsus (p = 0.002). However, neither the way the patients cleaned their contact lenses nor their enzyme cleaning frequency associated with the tear fluorescein clearance (p = 0.528 and 0.394, respectively). Meibomian gland dysfunction and corneal neovascularization did not correlate with the delayed tear clearance either (p = 0.111 and 0.717, respectively). CONCLUSIONS. Tear clearance in contact lens associated papillary conjunctivitis patients was delayed. We proposed that delayed tear clearance might increase the protein and inflammatory mediator concentrations in the tear film and contribute to the pathogenesis or aggravate the severity of contact lens associated papillary conjunctivitis.     

Ocular allergy: causes and therapeutic options

Ocular allergic eye conditions are among the most common anterior eye problems encountered in optometric practice. There are six common forms of ocular allergy: seasonal allergic conjunctivitis, perennial allergic conjunctivitis, vernal keratoconjunc‐tivitis, atopic keratoconjunctivitis, contact lens associated papillary conjunctivitis and contact ocular allergy. Here, we review the current understanding of the pathophysiol‐ogy underlying ocular allergic conditions and describe the different causes and forms of allergic eye disease and different treatment options.     

Contact lens complications

Complications associated with contact lenses range from mild to severe and occur with all lens modalities. Contact lens wear can cause a change in corneal physiology, which can lead to epithelial, stromal, and endothelial compromise. Other complications include lens deposition, allergic conjunctivitis, giant papillary conjunctivitis, peripheral infiltrates, microbial keratitis, and neovascularization. Pre-existing conditions can contribute to these complications, or they can occur in association with contact lens wear and care regimens. Patient-related factors, such as alteration of the recommended wearing or replacement schedules and noncompliance with recommended contact lens care regimens for economic reasons, convenience, or in error, contribute to contact lens-related complications and have led to difficulty in accurate determination of complication rates among the various lens wear modalities. Complications may require discontinuation of contact lenses, topical therapy, and changes in contact lens wearing schedules, materials, and care solutions. On initial lens fitting and follow-up evaluations, practitioners should review contact lens replacement and cleaning regimens with patients and discuss complications. To avoid serious complications, patients should be reminded to remove their contact lenses as soon as ocular irritation occurs, and to call their eye care practitioner immediately if symptoms persist.     

Grading contact lens complications under time constraints.

PURPOSE: To investigate the effect of observation time on the precision of grading the severity of contact lens complications. METHODS: Twenty-five optometry students used the Efron Grading Scales for Contact Lens Complications to grade the severity of one image of each of the 16 forms of anterior eye pathology depicted in the Efron scales. This procedure was repeated for observation times of 0.1, 2, and 60 s. RESULTS: Overall, significantly greater grading precision (smaller standard deviation of mean grades) was demonstrated for longer observation times (p < 0.004); however, certain complications appear to require longer observation times for precise grading. There was a highly significant dependence of the mean grade on image (p < 0.0001), observation time (p < 0.0001), and observation time-image interaction (p < 0.0001). CONCLUSIONS: Overall, a brief viewing time of a few seconds is typically all that is required for precise grading of ocular complications of contact lens wear. Some forms of pathology are more complex and may require more time to grade precisely.     

Changes in ocular physiology, tear film characteristics, and symptomatology with 18 months silicone hydrogel contact lens wear.

PURPOSE: The purpose of this study was to evaluate the longitudinal changes in ocular physiology, tear film characteristics, and symptomatology experienced by neophyte silicone hydrogel (SiH) contact lens wearers in a daily-wear compared with a continuous-wear modality and with the different commercially available lenses over an 18-month period. METHODS: Forty-five neophyte subjects were enrolled in the study and randomly assigned to wear one of two SiH materials: lotrafilcon A or balafilcon A lenses on either a daily- (LDW; BDW) or continuous-wear (LCW; BCW) basis. Additionally, a group of noncontact lens-wearing subjects (control group) was also recruited and followed over the same study period. Objective and subjective grading of ocular physiology were carried out together with tear meniscus height (TMH) and noninvasive tear breakup time (NITBUT). Subjects also subjectively rated symptoms and judgments with lens wear. After initial screening, subsequent measurements were taken after 1, 3, 6, 12, and 18 months. RESULTS: Subjective and objective grading of ocular physiology revealed a small increase in bulbar, limbal, and palpebral hyperemia as well as corneal staining over time with both lens materials and regimes of wear (p < 0.05). No significant changes in NITBUT or TMH were found (p > 0.05). Subjective symptoms and judgment were not material- or modality-specific. CONCLUSIONS: Daily and continuous wear of SiH contact lenses induced small but statistically significant changes in ocular physiology and symptomatology. Clinical measures of tear film characteristics were unaffected by lens wear. Both materials and regimes of wear showed similar clinical performance. Long-term SiH contact lens wear is shown to be a successful option for patients.     

Vascular response to extended wear of hydrogel lenses with high and low oxygen permeability.

PURPOSE: The purpose of this study was to determine the impact of extended wear of high and low oxygen permeability (Dk) lenses on the development or resolution of limbal hyperemia and corneal neovascularization in a randomized prospective clinical trial. METHODS: Adapted daily-wear contact lens wearers were randomly assigned to one of two groups. The low-Dk group (N = 23) wore etafilcon A lenses (Dk/t = 40) for up to 7 days and 6 nights, and the high-Dk group (N = 39) wore lotrafilcon A lenses (Dk/t = 175) for up to 30 days and nights. Limbal hyperemia and neovascularization were assessed and graded during 9 months of extended wear. A stratified analysis to determine how change in ocular redness depended on initial presentation was also conducted. RESULTS: On a 0 to 100 scale, extended wear of low-Dk lenses resulted in a 16-point increase in limbal hyperemia (p < 0.0001); no significant change occurred with the high-Dk lenses. The difference was greatest for low-Dk participants who initially presented with lower levels of hyperemia (N = 18). There was a slight resolution of redness in participants who initially presented with higher levels of hyperemia (N = 10) after wearing the high-Dk lenses. Neovascularization increased by an average of 0.5 on a scale of 0 to 4 in low-Dk lens wearers (p < 0.0001) but remained unchanged in the high-Dk lens wearers. The increase was most marked for the low-Dk group with lower levels of neovascularization at baseline. CONCLUSIONS: Subjects who wore lenses with higher oxygen permeability for 9 months of extended wear exhibited a lower vascular response of the ocular surface compared with subjects who wore lenses of lower oxygen permeability for the same period. This result was found both for the surface limbal vessels and in the deeper neovascular stromal vessels. Moderate neovascularization also developed after 3 months of extended wear of low-Dk hydrogels, whereas high-Dk lenses caused no neovascularization.     

A 6-month follow-up of successful refits from daily disposable soft contact lenses to continuous wear of high-Dk silicone-hydrogel lenses

PURPOSE: To compare, in routine optometric practice, the outcome of keeping successful soft contact lens (SCL) wearers in their lenses to re-fitting them with continuous wear of silicone hydrogel (SiH) lenses. METHODS: Forty-nine successful daily disposable lens wearers were recruited; 19 continued to wear daily SCLs and 30 were refitted with high-Dk SiH lenses on a 30-day/night schedule. Patients were assessed at baseline, 3 and 6 months by slit lamp examination along with the Efron grading scales, and central corneal thickness (CCT) and the corneal endothelium were assessed by non-contact specular microscopy. RESULTS: No substantial changes in subjective vision, refraction, visual acuity or overall lens comfort occurred for those completing the study, although five SiH lens wearers did discontinue due to reduced comfort, eyelid problems or seasonal allergy. Contact lens induced peripheral ulcers (CLPU) were observed in three patients in the first 3 months in the SiH lens group and these were also discontinued. Over the 6 month period, a complete set of records was obtained for 16 in each group. For those completing the study, lens dryness scores were variable, but there was a slight improvement in favour of SiH lenses. Small, but statistically significant, reductions in corneal staining, bulbar hyperaemia, and limbal neovascularisation in favour of the SiH lenses were also evident but mainly because of further increases in the daily lens wearers. Contact lens induced papillary conjunctivitis (CLPC) and corneal endothelial polymegethism were mild to moderate and showed slight increases in the daily lens wearers at 6 months. CONCLUSIONS: The present studies confirm that the continuous wear of SiH lenses for up to 30 days can be considered as an alternative to daily disposable soft lens wear, but is not suitable for everyone.     

Acquired ptosis secondary to vernal conjunctivitis in young adults

PURPOSE: To establish a relation between prolonged severe vernal conjunctivitis and upper eyelid ptosis. METHODS: The study consisted of 12 patients between the ages of 19 and 32 years with acquired ptosis who presented in our clinic between September 2001 and February 2005. Potential factors responsible for acquired ptosis were investigated in all patients, with specific attention to the history and severity of vernal conjunctivitis. RESULTS: We found vernal conjunctivitis to be the identifiable cause in 8 men and 4 women with acquired ptosis. There was neither contact lens usage nor trauma or ocular surgery history in their medical records. The blepharoptosis was caused by levator disinsertion and recession of the aponeurosis. The pathology improved in each case after reattachment of the aponeurosis to the superior tarsal border. CONCLUSIONS: These findings suggest that prolonged severe vernal conjunctivitis may induce a lower position of the upper eyelid and eventually lead to ptosis through levator disinsertion that is similar to involutional ptosis. We believe that chronic inflammation of the upper eyelid with giant papillary conjunctivitis and persistent rubbing of the eyelids may be responsible for the development of this pathology.     

The ocular response to extended wear of a high Dk silicone hydrogel contact lens

Purpose: A four‐month extended wear clinical trial was conducted to compare die ocular effects of a high Dk Balafilcon A silicone hydrogel lens and a low Dk HEMA 38.6 per cent H²O soft lens. Method: Twenty‐four subjects who were adapted to daily wear of soft lenses wore a high Dk lens in one eye and a low Dk HEMA lens in the other eye for four months on an extended wear basis after one week of daily wear. Thirteen progress evaluations were conducted using standard clinical procedures. Results: Eighteen subjects (75 per cent) completed the study. The high Dk lens induced significantly less bulbar and limbal injection and corneal vascularisation dian the low Dk HEMA lens (p < 0.05). Epithelial microcysts were observed only in the eyes wearing the low Dk lens. A significant increase in myopia was found in die eyes wearing die low Dk HEMA lens (mean = 0.50 D, p < 0.01) compared to die insignificant myopic increase of 0.06 D in the eyes wearing the high Dk lens. Three subjects developed small infiltrates in the high Dk lens wearing eyes and significantly more post‐lens debris was observed under the high Dk lens. Six subjects developed papillary conjunctivitis in die eye wearing silicone hydrogel lenses but only two of those were discontinued from the study. Conclusion: No hypoxia‐related effects were observed with extended wear of the high Dk Balafilcon A silicone hydrogel lens.     

An unusual case of floppy eyelid syndrome

A 51-year-old obese man with a history of nocturnal upper eyelid eversion secondary to floppy eyelids presented with a Staphylococcus aureus corneal ulcer. No papillary conjunctivitis was present. The corneal ulcer was treated successfully. This case demonstrates the importance of ruling out spontaneous nocturnal lid eversion as a cause for unexplained ocular surface pathology and emphasizes the fact that the floppy eyelid syndrome may present in the absence of classic papillary conjunctivitis.     

Differential diagnosis and therapy of gigantopapillary conjunctivitis

If wearers of contact lenses present with secretion and incompatibility of the contact lens, simple ectropionation of the upper eyelids often is sufficient to diagnose a giant papillary conjunctivitis as the cause. This form of papillary hypertrophy affecting wearers of both hard and soft contact lenses is morphologically similar to vernal conjunctivitis, which should be considered in cases of corneal ulceration resistant to therapy. The histological difference between the two forms of papillary hypertrophy is that contact lens-induced giant papillary conjunctivitis shows remarkably less eosinophilic infiltration of the papillary stroma. Both forms of papillary hypertrophy seem to be based on a complex immunologic reaction.     

Delayed ocular complications of mustard gas poisoning and the relationship with respiratory and cutaneous complications

BACKGROUND: This study was aimed to determine the correlation between ocular complications and respiratory or cutaneous complications in a group of 40 Iranian veterans with late complications of sulphur mustard (SM) poisoning. METHODS: Thorough ophthalmologic examination was performed on all severely SM-poisoned veterans in the province of Khorasan, Iran. Spirometric evaluation of pulmonary function, as well as estimation of the burned skin area, was performed for all the patients. The severities of ocular, respiratory and cutaneous complications were classified into four grades in each patient and were compared with each other, using Spearman's rank correlation test. RESULTS: Forty male patients (aged 43.8 +/- 9.8 years) with confirmed SM poisoning were studied 16-20 years after their initial exposure. Common symptoms were recorded as itching (42.5%), burning sensation (37.5%), photophobia (30%) and tearing (27.5%). Abnormal conjunctival and limbal findings were chronic conjunctivitis (17.5%), perilimbal hyperpigmentation (17.5%), vascular tortuosity (15%) and limbal ischaemia (12.5%). Abnormal corneal findings were subepithelial opacity (15%), corneal thinning (15%), diffuse corneal opacity (10%), neovascularization (7.5%) and epithelial defects (5%). A significant positive correlation was found between the severity of ocular and respiratory complications (r = 0.322, P = 0.043). Cutaneous complications revealed no significant correlation with either ocular or respiratory complications. CONCLUSIONS: SM causes delayed destructive lesions in the ocular surface and cornea, leading to progressive visual deterioration and ocular irritation. Late complications of SM poisoning in the eyes, respiratory system and skin are mainly due to SM's local irritant effects.     

Ocular complications of vernal keratoconjunctivitis.

BACKGROUND: The objective of this study was to assess the ocular complications and visual loss among patients with severe vernal keratoconjunctivitis (VKC). METHODS: A total of 58 consecutive patients (52 boys and 6 girls aged 8 to 17 [mean 12.2] years) with severe active VKC were examined at two tertiary care facilities in Riyadh, Saudi Arabia, between 1995 and 1997. Patients were deemed to have severe VKC if they had had symptoms for at least 2 years, had diffuse palpebral conjunctival edema and thickening with papillary hypertrophy (P3) and giant papillary conjunctivitis, and had limbal infiltration of 180 degrees or more. Visual acuity was measured with the standard Snellen visual acuity chart. Visual impairment was assessed by means of the World Health Organization criteria for visual disabilities. Visual loss was defined as either blindness or visual impairment. RESULTS: Twelve patients (21%) had a best corrected visual acuity in one or both eyes of 20/200 or less, 20 (34%) had 20/50 to 20/200 vision, and 26 (45%) had 20/20 to 20/50 vision. The ocular complications that led to visual loss among 32 patients included steroid-induced cataract (8 patients), steroid-induced glaucoma (4), central corneal scars (7), irregular astigmatism (4), keratoconus (3) and limbal tissue hyperplasia (3). Of the 32 patients 12 had dry eye syndrome, which may have contributed to the visual loss. INTERPRETATION: Severe VKC in developing countries is a potentially blinding disease. Visual loss may be due to corneal complications, including corneal scars, astigmatism and keratoconus, as well as complications of the unsupervised use of topically administered corticosteroids.