Role of artificial tears with and without hyaluronic acid in controlling ocular discomfort following PRK: a randomized clinical trial

AIM: To compare outcomes of applying preservative free artificial tears (PFAT) with and without hyaluronic acid (HA) in early postoperative course following photorefractive keratectomy (PRK). METHODS: In this triple-blinded randomized clinical trial, PRK procedure was performed on both eyes of 230 patients. Following PRK, patients were divided into three groups: the HA+ group, 44 patients PFAT containing HA; the HA- group, 71 patients PFAT without HA were administered 5 times per day (every 4h); the third group, 115 patients received no PFAT before lens removal. On the 1st and 4th postoperative day, Visual Analogue Score (VAS) was utilized to evaluate patient’s level of pain. Participants were asked to complete a questionnaire about the severity of eye discomfort ranked from 0 to 10 (0=no complaint; 10=most severe complaint experienced). RESULTS: In eyes receiving PFAT with or without HA (Drop group), mean scores for epiphora, foreign body sensation, and blurred vision on the 1st postoperative day were statistically lower (P<0.05). Filamentous keratitis (FK) was detected in 11 (4.7%) eyes, and recurrent corneal erosion (RCE) was observed in 5 (2.1%) eyes. In the control group, FK was noted in 16 (6.9%) eyes while 13 (5.6%) eyes had RCE and 5 (2.1%) eyes had corneal haze. The rate of complications was statistically lower in Drop group (P=0.009). However, the aforementioned scores were not statically different between HA+ and HA- group one and two (P=0.29). CONCLUSION: Following PRK, applying PFAT with and without HA yields faster visual recovery, decreases postoperative ocular discomfort and haze formation; however there is no additive effect for HA.     

Identification and validation of tumor microenvironment-related lncRNA prognostic signature for uveal melanoma

AIM: To compare outcomes of applying preservative free artificial tears (PFAT) with and without hyaluronic acid (HA) in early postoperative course following photorefractive keratectomy (PRK). METHODS: In this triple-blinded randomized clinical trial, PRK procedure was performed on both eyes of 230 patients. Following PRK, patients were divided into three groups: the HA+ group, 44 patients PFAT containing HA; the HA- group, 71 patients PFAT without HA were administered 5 times per day (every 4h); the third group, 115 patients received no PFAT before lens removal. On the 1st and 4th postoperative day, Visual Analogue Score (VAS) was utilized to evaluate patient’s level of pain. Participants were asked to complete a questionnaire about the severity of eye discomfort ranked from 0 to 10 (0=no complaint; 10=most severe complaint experienced). RESULTS: In eyes receiving PFAT with or without HA (Drop group), mean scores for epiphora, foreign body sensation and blurred vision on the 1st postoperative day were statistically lower (P<0.05). Filamentous keratitis (FK) was detected in 11 (4.7%) eyes, and recurrent corneal erosion (RCE) was observed in 5 (2.1%) eyes. In the control group, FK was noted in 16 (6.9%) eyes while 13 (5.6%) eyes had RCE and 5(2.1%) eyes had corneal haze. The rate of complications was statistically lower in Drop group (P=0.009). However, the aforementioned scores were not statically different between HA+ and HA- group one and two (P=0.29). CONCLUSION: Following PRK, applying PFAT with and without HA yields faster visual recovery, decreases postoperative ocular discomfort and haze formation; however there is no additive effect for HA.     

Comparison of Postoperative Pain Following Laser-assisted Subepithelial Keratectomy and Transepithelial Photorefrac-tive Keratectomy:a Prospective,Random Paired Bilateral Eye Study

Purpose： To compare postoperative pain following laser-as- sisted subepithelial keratectomy （LASEK） and transepithelial photorefractive keratectomy （T-PRK, two-step surgery） and alleviate postoperative subjective pain. Methods： Thirty patients （60 eyes） with myopia or myopic astigmatism were consecutively recruited into this prospective, randomized paired study. Patients underwent LASEK in one eye, and T-PRK in the other. The degree of pain was rated on a scale of 0-10 on postoperative days 1,2 and 3. Uncorrected visual acuity （UCVA） and subepithelial corneal haze were as- sessed at postoperative 1 and 3 months. Results： The pain was relieved on the 4th postoperative day in all patients, healing of corneal epithelium was observed at 4-5 days after surgery and contact lenses were removed promptly.At postoperative 1 day, the mean subjective pain score in the LASEK group was 3.2±1.88 and 4.43±1.61 in T- PRK group （P=0.008）.No significant difference was found be- tween two groups on postoperative 2 and 3 days. At postoper- ative 3 months, the percentage of UCVA t〉0.8 in the LASEK group was 100% and 96.7% in the T-PRK group （P=0.24）, 93.3% of patients in the LASEK with UCVA ≥ 1.0 and 90% in the T-PRK group（P=0.64）. In the LASEK group, the value of corneal haze was 0.26±0.21 and 0.27±0.25 in the T-PRK group（P=0.877）.     

【In Press】Impact of topical nonsteroidal anti-inflammatory drugs in prevention of macular edema following cataract surgery in diabetic patients

AIM: To evaluate the efficacy of prophylactic administration of topical non-steroidal anti-inflammatory drugs on macular edema following cataract surgery in diabetic patients, and comparing between types of non-steroidal anti-inflammatory drugs (ketorolac tromethamine 0.4% and nepafenac 0.1%). METHODS: Group1 (control) received artificial tears substitute as a placebo group, group 2 (Nepafenac) received topical nepafenac 0.1%, and group 3 (Ketorolac) received topical ketorolac tromethamine 0.4%. Patients were examined postoperatively after completing one week, one month, two months and three months’ intervals for evaluating cystoid macular edema (CME) development. The main study outcomes were achieving the best corrected visual acuity (BCVA) and change in the central macular thickness measured with optical coherence topography (OCT). RESULTS: Eighty eyes of 76 patients were included in this study. BCVA showed a statistically significant difference at the third month postoperative follow up between the control group and the nonsteroidal anti-inflammatory (NSAIDs) groups. There was an increase in the central macular thickness (CMT) in all cases starting from postoperative first week until third month. CMT showed a statistically significant difference between control group and NSAIDs groups from postoperative first month until third month. There was no statistically significant difference between Nepafenac and Ketorolac groups in BCVA and OCT CMT. CONCLUSION: Prophylactic preoperative and postoperative NSAIDs may have a role in reducing the frequency and severity of CME in diabetic eyes following cataract surgery.     

A two different chemoprophylaxis approaches after phacoemulsification surgery in one thousand patients in Iraq

AIM: To evaluate the effectivity of the combination of intracameral moxifloxacin 0.1% with subconjunctival triamcinolone acetonide 4 mg as prophylaxis of infection and inflammation after phacoemulsification in comparison with topical medication treated group. METHODS: A total one thousand patients with age range from 38 to 70 years old who scheduled for phacoemulsification were divided into 2 groups of no statistically significant differences in age, preoperative intraocular pressure (IOP) and central macular thickness (CMT), P=0.6, 0.9 and 0.8 respectively. The surgeries were done by 2 surgeons each one planned to use one method of prophylaxis at Eye Speciality Private hospital, Baghdad, Iraq. For the 1st group of patients (500) a topical moxifloxacin hydrochloride 0.5% and dexamethasone 0.1% eye drops were prescribed four times a day for 1mo postoperatively. For the 2nd group intracameral (IC) diluted moxifloxacin at 0.1% with subconjunctival (SC) triamcinolone 4mg in 0.4 cc were administered at the conclusion of the surgery. Follow up visits were on the first postoperative day, 1wk, 1mo, and 3mo postoperatively. Anterior chamber (AC) reaction was examined during the 4 visits while IOP was measured during the last 3 and CMT was measured only in the last one. RESULTS: The current clinical trial study compared 2 samples with 2 different prophylaxis methods. No endophthalmitis case reported in both group. By a 2-Sample t-test, the IC-treated group (group 2) had statistically significant lower AC cells at the 1st day postoperative visit than the other group while there were no statistically significant differences at 1wk, 1 mo and 3mo visits between the 2 groups. There was no statistically significant difference at 3mo visits in IOP and CMT between the two groups. A breakthrough inflammation rate with the topical medication was (9.6%) while in the other group (IC treated ) was 4.0%. A significant IOP elevation ≥10 mm Hg at 1mo in 2.4% within the topical medication group which was higher than the rate in the other group (0.8%). CONCLUSION: In addition to the safety and effectivity of the combination of intracameral moxifloxacin and subconjunctival triamcinolone in preventing infection and inflammation after cataract surgery. The majority (480) of our included patients didn’t require any topical postoperative medication that is cost saving for the patient, helped patients who were unable to administer topical medication, and decreased chance of complication related to patient poor adherence to postoperative medication.     

Clinical Evaluation of Pranoprofen Combined with Fluorometholone Eye Drops on Postoperative Reaction of Corneal Cross-linking

 Purpose: To evaluate the efficacy and safety of pranoprofen eye drops for reducing postoperative ocular pain and inflammation after corneal cross-linking (CXL). Methods: Twenty-seven patients (38 eyes) with keratoconus undergoing CXL were examined and randomly divided into control (12 cases; 18 eyes) and experimental groups (15 cases; 20 eyes). The patients in the control group were given fluorometholone eye drops, and those in the experimental group were administered with fluorometholone combined with pranoprofen eye drops．Corneal irritation and haze were compared between the two groups at 1 month postoperatively． Results: At 1 to 3 days after surgery,the corneal irritation in the experimental group was significantly reduced compared with that in the control group (P＜0.05), but there was no significant difference on 5 to 7 days postoperatively (P＞0.05)．The average degree of haze in the experimental group was significantly lower than that in the control group 1 month after surgery (P＜0.05), but there was no significant difference in the best-corrected vision acuity and intraocular pressure between the two groups. There were 2 cases with >20 mmHg intraocular pressure in the control group. Conclusion: The combined use of fluorometholone and pranoprofen can significantly reduce inflammatory response,alleviate corneal irritation at early stage after CXL,effectively prevent and control the average of haze,and reduce the incidence of steroid-induced ocular hypertension after surgery．     

Efficacy of Carbamazepine Combined with Botulinum Toxin A in the Treatment of Blepharospasm and Hemifacial Spasm

 Purpose: To observe the efficacy of the combined treatment of carbamazepine and botulinum toxin A for blepharospasm and hemifacial spasm. Methods: Fifty-eight patients with either blepharospasm or hemifacial spasm were randomly divided into treatment and control groups. In the treatment group, 30 patients were administered with local intramuscular injections of botulinum toxin A and oral carbamazepine 100 mg/time,3 times/day for 60 days. Twenty-eight subjects in the control group underwent local intramuscular injections of botulinum toxin A only. Results: After combined treatment, the complete remission rate was 90%, which was significantly higher than that of the of the control group (67.9%, P<0.05，X2=4.733). However, no statistical significance was noted regarding the duration of therapeutic effects between the treatment group (range 14~40 weeks; 19.2 weeks on average) and control group (range 12~36 weeks; 18 weeks on average). Conclusion: The combined therapy of carbamazepine and topical injections of botulinum toxin A had increased efficacy in the treatment of blepharospasm or hemifacial spasm, but had no significant effect in terms of the duration of the therapeutic effect.     

Utilizing dexamethasone intravitreal implant to control postoperative inflammation in refractory uveitis undergoing cataract surgery

AIM:To report the effectiveness of intravitreal implantation of dexamethasone implant(Ozurdex)after phacoemulsification and intraocular lens implantation in refractory uveitis patients.METHODS:This single-center retrospective study conducted for refractory pan-uveitis patients who underwent cataract surgery combined with intravitreal Ozurdex implantation.The main outcome measurements were bestcorrected visual acuity(BCVA),central retinal thickness(CRT),grade of anterior chamber cell(AAC),intraocular pressure(IOP),and systemic/ocular adverse events.RESULTS:Ten eyes of 7 patients were included.BCVA showed significant improvement at 1 mo(P=0.004),3 mo(P=0.0004),and 6 mo(P=0.001)post operation.There were no statistically significant differences in the postoperative CRT among follow-up groups(P>0.05).No significant differences were observed in the baseline IOP when compared to 1,3,and 6 mo(all P>0.05)post operation.One patient developed a transient elevated IOP post injection.Two eyes(20%)developed posterior capsular opacifications and underwent neodymium-doped yttrium aluminum garnet(Nd:YAG)laser capsulotomy.In six patients(8 eyes,71.4%),the systemic steroid usage was reduced to below 10 mg/d.The patients experienced a mean of 1.4±0.52 recurrences of inflammation in the 6 mo before operation and 0.7±0.48 in the 6 mon post operation.The mean recurrence time was 13±0.58 wk(range 12-14 wk)post operation.In five of seven patients(7 out of 10 eyes),inflammation relapse was developed postoperatively.Only one patient(2 eyes)needed increased amounts of oral corticosteroids.Intraocular inflammation recurrence in the remaining patients was controlled by topical steroids.CONCLUSION:Ozurdex is considered a safe and effective approach to control postoperative inflammation in cataract surgery for patients with refractory uveitis in our study.After the disappearance of Ozurdex’s antiinflammatory effects over time,in most cases the recurrent inflammation can be controlled by topical steroids.     

Effect of eccentricity of overnight lenses on 2-year axial growth and visual quality

AIM: To explore the effect of eccentricity of overnight orthokeratology (OK) lenses on 2-year eye axial growth and visual quality. METHODS: Based on the degree of eccentricity of OK lenses, patients were divided into three groups: a low degree of eccentricity group (degree of eccentricity ≤0.5 mm), a group of moderate eccentricity (eccentric degree >0.5-1.0 mm) and a group with a high degree of eccentricity (eccentric degree >1-1.5 mm). The degree of eccentricity of the OK lens, spherical equivalent (SE), the uncorrected visual acuity (UCVA) after wearing OK lenses, axial length (AL) before and after wearing OK lenses, total higher-order aberrations (HOA), comas, and spherical aberrations (SA) for 3 mm pupils were analyzed. The difference among the three groups for all parameters was compared using the Kruskal-Wallis H Rank-Sum test. RESULTS: The study retrospectively analyzed 75 cases (139 eyes). In the low eccentricity group (53 eyes), the mean age was 11.4±2.4y, SE was -3.24±1.48 D, and AL was 24.85±1.01 mm. In the moderate eccentricity group (53 eyes), the mean age was 11.4±2.2y, SE was -3.22±1.29 D, and AL was 25.15±0.92 mm. In the high eccentricity group (31 eyes), the mean age was 11.5±1.9y, SE was -3.54±1.43 D, and AL was 24.95±0.84mm. After two years, there was no significant difference in the changes of the axis among the three groups (P=0.089). The HOA, SA, and coma in the high eccentric group were significantly higher than in the middle eccentric group (P<0.05). The HOA, SA, and coma in the high eccentric group were also significantly higher than those in the low eccentric group (P<0.05). CONCLUSION: For OK lenses, it is unnecessary to strictly require the absolute centralization of the lens position. An unnecessary change of the lenses may delay the eye-axis control. However, the balance between axial control and visual quality should be assessed.     

Effects of medication methods after simple and effective probing of lacrimal passage

AIM:To evaluate the effect of reducing the use of antibiotics in the treatment of infant bacterial dacryocystitis after probing of the lacrimal duct.METHODS: A total of 542 cases of children under one year old and accepting nasolacrimal duct probing treatment were divided into two groups, which were treated with topical and oral antibiotics, respectively. Conjunctival sac secretions were used as a control index of bacterial infection, whereas the disappearance of epiphora symptoms and lacrimal passage patency were used as cure indexes. The χ² test was used to compare enumeration and measurement data, and a statistical significance was set at P<0.05. The therapeutic effect on the two groups of postoperative patients was investigated.RESULTS:In the two study groups, no significant differences in gender, age and postoperative control of lacrimal sac infection were observed. The cure rates after three probing operations also showed no significant difference.CONCLUSION:After probing of the lacrimal passage, results of this study confirmed that postoperative medication without oral antibiotics but an ophthalmic dosage of antibiotics was a simple and effective treatment method.     

溴芬酸钠滴眼液对RPK术后止痛效果的观察

目的:观察溴芬酸钠滴眼液用于PRK术后止痛的临床效果。方法:选取双眼行PRK术患者60例,术前及术后常规局部使用抗菌素、激素。根据局部使用非甾体抗炎药随机分组,溴芬酸钠滴眼液组30例60眼,术前3d开始点用溴芬酸钠滴眼液2次/d,至术后5d;对照组30例60眼,术前3d开始点用普拉洛芬滴眼液4次/d,至术后5d。采用5级疼痛评估法,即无痛0度,轻痛1度,中度痛2度,重度痛3度,严重痛4度。记录术后3d内最高疼痛数值。结果:疼痛调查表回收率100%。溴芬酸钠组0度20例(66.66%),1度10例(33.33%);对照组0度10例(33.33%),1度10例(33.33%),2度7例(23.33%),3度3例(10.00%)。统计学结果显示溴芬酸钠组与对照组之间有统计学差异(P<0.05)。结论:溴芬酸钠滴眼液用于PRK术后止痛效果优于普拉洛克滴眼液,并且副作用小,依从性好。     

Oral gabapentin for the treatment of postoperative pain after photorefractive keratectomy

PURPOSE: To evaluate oral gabapentin for postoperative pain after photorefractive keratectomy (PRK). DESIGN: Prospective, nonrandomized clinical trial. METHODS: In additional to a standard regimen of topical antibiotics, topical steroids, and topical tetracaine as required, all PRK patients at our laser vision center were treated after surgery for pain for a two-month period with Percocet (oxycodone/acetaminophen) [Endo Pharmaceuticals; Chadds Ford, Pennsylvania, USA] 5 mg/325 mg as required for three days (control group). Patients completed a pain assessment survey using a faces pain scale (from zero through 6) on the evening of surgery and each subsequent morning and evening until postoperative day 3. A successive cohort of patients received Neurontin (gabapentin) [Pfizer, New York, New York, USA] 300 mg thrice daily (first dose administered two hours or more before the procedure) as an oral pain medication for three days, and the same survey data were collected. RESULTS: Data were collected on 141 patients in each cohort. Successful pain management score (defined as faces zero through 2 on the scale) differences did not reach statistical significance between the two cohorts except on the morning of the second postoperative day, when gabapentin was superior. On all postoperative days, patients in the oxycodone/acetaminophen cohort used significantly less tetracaine eye drops as required. The percent of patients rating overall pain experience as better than expected was 35% and 36%, those rating pain experience as about what was expected was 50% and 49%, and those rating pain experience as worse than expected was 15% and 15% in the oxycodone/acetaminophen and gabapentin cohorts, respectively. CONCLUSIONS: We found no difference in overall subjective pain management ratings between gabapentin and oxycodone/acetaminophen for postoperative PRK pain, although gabapentin was associated with significantly more frequent use of anesthetic eye drops as required.     

Intraoperative mitomycin and corneal endothelium after photorefractive keratectomy

PURPOSE: To determine whether there is an increased risk to the corneal endothelium when mitomycin C (MMC) is administered after photorefractive keratectomy (PRK). DESIGN: Prospective, randomized, double-blind, placebo-controlled crossover trial. METHODS: Corneal endothelium was analyzed preoperatively and postoperatively in 18 eyes of nine patients who were administered either MMC- or balanced salt solution (BSS)-supplemented PRK at Codet Aris Vision, Tijuana, Mexico. After laser ablation, one eye was randomly assigned to intraoperative topical MMC 0.02% treatment for 30 seconds, and the fellow eye (the control eye) was treated in a standard fashion with topical BSS. Preoperative pachymetry and endothelial cell count were performed and compared with postoperative measurements after one month and three months. Main outcome measure studied was endothelial cell loss. RESULTS: There was no significant difference in the preoperative endothelial cell count between the 2 groups: MMC group 2835 +/- 395, control group 2779 +/- 492, P = .62. In the control group, at one month and three months the difference in the endothelial cell count was not statistically significant (P = .27, P = .14, respectively). However, in the MMC group the endothelial cell loss was statistically significant: at one month 14.7 +/- 5.1%, and at three months 18.2 +/- 9.0% (P = .0006, P = .002, respectively). CONCLUSIONS: The use of intraoperative topical MMC 0.02% for 30 seconds after PRK may affect the endothelial cell count.     

Epithelial healing and clinical outcomes in excimer laser photorefractive surgery following three epithelial removal techniques: mechanical, alcohol, and excimer laser

PURPOSE: To evaluate epithelial healing, postoperative pain, and visual and refractive outcomes after photorefractive keratectomy (PRK) using three epithelial removal techniques. DESIGN: Prospective, nonrandomized, comparative trial. METHODS: SETTING: Department of Ophthalmology, Yonsei University College of Medicine and Balgensesang Ophthalmology Clinic, Seoul, Korea. INTERVENTIONS: For the PRK procedure, the corneal epithelium was removed in one of three ways: mechanically (conventional PRK [PRK]) in 88 eyes of 44 patients; using excimer laser (transepithelial PRK [tPRK]) in 106 eyes of 53 patients; or using 20% diluted alcohol, laser-assisted subepithelial keratomileusis (LASEK) in 106 eyes of 53 patients. MAIN OUTCOME MEASURES: Epithelial healing, postoperative pain, uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), and remaining refractive error. RESULTS: The mean postoperative pain scores were 4.84 +/- 1.45 for PRK, 4.71 +/- 1.62 for tPRK, and 4.63 +/- 1.52 for LASEK (P = .125). The mean epithelial healing rates were 12.3 +/- 4.6 for PRK, 15.2 +/- 4.9 for tPRK, and 18.1 +/- 5.2 mm2/day for LASEK (P < .001). The postoperative 6-month remaining mean spherical equivalents (diopters) were -0.46 +/- 1.01 for PRK, 0.18 +/- 0.91 for tPRK, and -0.82 +/- 1.18 for LASEK (P = .01). The LASEK group showed less favorable UCVA than other groups. There was no significant difference in BSCVA between the groups. CONCLUSIONS: Postoperative pain, subepithelial opacity and BSCVA were similar regardless of the epithelial removal procedure. A faster epithelial healing rate did not result in better visual or refractive outcomes. Using the same nomogram, tPRK resulted in a slight overcorrection, and LASEK resulted in a slight undercorrection.     

Vitreal penetration of oral and topical moxifloxacin in humans

PURPOSE: To investigate the vitreal penetration of moxifloxacin after oral and topical administration. DESIGN: Prospective, nonrandomized clinical trial. METHODS: Twenty-four patients were assigned to one of four dosing groups: control (n = 3), which received no medication; oral (n = 8), which received two 400 mg oral doses of moxifloxacin before surgery; topical (n = 8), which received one drop of topical moxifloxacin 0.5% every 15 minutes for the hour preceding surgery; and combined (n = 5), which received two 400 mg oral doses and one drop of topical moxifloxacin 0.5% hourly for 18 hours prior to surgery. Vitreous samples were obtained and analyzed. RESULTS: Control, below quantifiable levels; oral, 1.553 +/- 0.33 microg/ml; topical, 0.027 microg/ml; and combined, 2.219 +/- 0.71 microg/ml. One topical patient developed postoperative endophthalmitis. CONCLUSIONS: In contrast to topical moxifloxacin, oral moxifloxacin achieves significant levels in the noninflamed human vitreous.     

经上皮个性化表面切削术与器械法去上皮准分子激光角膜表面切削术在患者术后早期恢复情况的比较

目的比较经上皮个性化表面切削术与器械法去上皮准分子激光角膜表面切削术（PRK）的术后疼痛感、上皮愈合时间和早期视力恢复情况。方法非随机前瞻性临床对照研究。连续收集2009年3月18日至2009年10月28期间接受iVIS-Suite 100 Hz激光机切削的经上皮个性化表面切削手术患者15例（30眼，组1），接受Amoils刷器械法去上皮并由Wavelight Allegretto 400 Hz激光机切削的器械法去上皮PRK手术患者15例（30眼，组2）。术后每24小时评估患者上皮愈合情况及主观疼痛感直至上皮愈合。术后1、2、3、4周测量患者术后屈光度，裸眼视力以及最佳眼镜矫正视力。采用独立样本Wilcoxon秩和检验来比较两组患者主观疼痛程度的差别，其他数据比较使用独立样本t检验。结果组1和组2患者的平均上皮愈合时间分别为（2．6±0．5）d和（2．9±0．6）d，差异具有统计学意义（t=2．039，P=0．046）。术后第2天，组1患者疼痛感评分小于组2（Z=-3．535，P〈0．01），且组1患者在术后3d内的最强烈疼痛感评分和平均疼痛感评分均低于组2，差异均有统计学意义（Z=-2．261，P=0．024；Z=-2．982，P=0．003）。术后3周，组1患者平均裸眼视力为-0．068±0．088（10gMAR），组2为-0．024±0．069（10gMAR），差异有统计学意义（t=2．236，P=-0．030）。两组患者术后1至4周的最佳矫正视力和平均等效球镜度经分析差异均无统计学意义。结论单一步骤的经上皮个性化表面切削术与器械法去上皮PRK相比，上皮愈合时间更短，裸眼视力恢复更快，术后疼痛感更轻。两种手术的术后最佳眼镜矫正视力和屈光值无明显差异。     

Topical tetracaine with bandage soft contact lens pain control after photorefractive keratectomy

PURPOSE: A major disadvantage of photorefractive keratectomy (PRK) is pain and discomfort in the first three postoperative days. We tried to assess the efficacy and safety to the cornea of a limited amount of topical tetracaine given to patients for use when needed to manage severe pain. METHODS: Sixty-nine eyes of 49 patients who underwent PRK between June 21, 1996 and June 15, 1998 by a single surgeon were prospectively included. Approximately 10 drops of commercial, non-preserved 0.5% tetracaine were given to patients to use when needed to control severe pain. A bandage soft contact lens was applied. Patients were examined at 1 and 3 days after surgery, at which time corneal re-epithelization was assessed and the number of tetracaine drops used was noted. No systemic analgesic or topical non-steroidal anti-inflammatory was prescribed. RESULTS: All eyes healed within 3 days. The mean number of drops of tetracaine used was 2.3 drops over 3 days, although in 33 eyes (48%) the patient did not use any tetracaine. There was no correlation between the attempted correction in diopters and the number of drops used. No significant difference was found in the number of drops used in the second eye of patients who had both eyes treated. CONCLUSIONS: Limited use of topical anesthetics is an effective and safe analgesic option after PRK. Use of tetracaine in this protocol did not prolong the time to re-epithelialization. Giving only a limited amount of tetracaine to patients prevents abuse and toxicity to the cornea while managing severe pain.     

Comparison of postoperative pain in patients following photorefractive keratectomy versus advanced surface ablation

PURPOSE: To compare postoperative pain associated with advanced surface ablation versus traditional photorefractive keratectomy (PRK). SETTING: Codet-Aris Vision Institute, Tijuana, Mexico. METHODS: This prospective double-masked randomized study included 56 eyes of 28 myopic patients who received traditional PRK in 1 eye and advanced surface ablation in the contralateral eye. For advanced surface ablation, removal of corneal epithelium was performed by incubating the cornea with 18% ethanol. Subsequently, the epithelium was removed by a surgical microsponge. For eyes treated by PRK, mechanical debridement of corneal epithelium was performed with a surgical blade. Excimer laser corneal ablation was performed using the Nidek EC-5000 excimer laser in all eyes. On postoperative days 1 and 3, patients were instructed to rate their pain via 3 pain measuring tools: (1) a global subjective rating; (2) a 100 mm visual analog scale (VAS); and (3) an 11-point numerical rating scale. RESULTS: All 28 patients completed postoperative questionnaires on day 1 and day 3. On postoperative day 1, all reported pain in both eyes. Using the global assessment rating, patients reported statistically significant more pain in eyes treated by advanced surface ablation (P = .0037; confidence interval [CI], 59%-92%). Furthermore, based on the 11-point numerical rating scale, mean pain scores were significantly higher in the advanced surface ablation treated eyes (P = .0121), while the VAS mean pain scores were marginally significantly higher (P = .0822). On postoperative day 3, 23 patients reported the presence of some pain, at least in 1 eye. Using the global assessment rating, 70% of the those who had pain reported more pain in the advanced surface ablation-treated eye (advanced surface ablation 16/23 versus PRK 7/23) (P = .0931; 95% CI, 47%-87%). In addition, on postoperative day 3, advanced surface ablation-treated eyes demonstrated slightly higher mean pain scores based on the 11-point numerical rating scale and on the VAS; however, mean differences were not statistically significant (P = .3494 and P = .3337, respectively). CONCLUSIONS: Advanced surface ablation was associated with statistically significantly more postoperative pain than PRK on postoperative day 1. A greater percentage of patients reported more pain in the advanced surface ablation-treated eyes on day 3. Refractive surgeons should consider the postoperative pain associated with advanced surface ablation when deciding on the type of epithelial debridement for their patients.     

Epithelial healing and ocular discomfort after photorefractive keratectomy in children

OBJECTIVE: To document the rate of healing of the corneal epithelial defect created by photorefractive keratectomy (PRK) and the degree of discomfort experienced by children treated with PRK. SETTING: Baylor College of Medicine, Texas Children's Hospital, Houston, Texas, USA. METHODS: Ten patients between 3 and 10 years of age were treated with PRK for severe anisometropia. All had anisometropic amblyopia refractory to conventional therapy with glasses or contact lenses and occlusion therapy. The size of the corneal epithelial defect was documented daily until the defect healed completely. Postoperative discomfort was documented daily using a pain-assessment scale until the epithelial defect healed completely. RESULTS: Two children were treated with PRK for hyperopic anisometropia; the rest were treated for myopic anisometropia. Cumulatively, the corneal epithelium had healed completely by day 3 in 6 patients (60%), by day 4 in 9 patients (90%), and by day 5 in all patients. The mean healing time was 3.5 days. Patients experienced mild discomfort on the day of surgery and on the first postoperative day. They had minimal pain on day 2. After day 2, no patient reported pain or other discomfort. CONCLUSIONS: The corneal epithelial defect created by PRK healed promptly and was associated with minimal postoperative discomfort in children treated with the protocol described.     

Prospective randomized comparison of simultaneous and sequential bilateral photorefractive keratectomy for the correction of myopia

BACKGROUND AND OBJECTIVE: To evaluate the efficacy and safety of simultaneous bilateral photorefractive keratectomy (PRK). PATIENTS AND METHODS: There were 52 patients (104 eyes) with myopia less than -6 diopters entered in this prospective trial and randomized to simultaneous or sequential bilateral PRK. Main outcome measures were uncorrected visual acuity (UCVA), percentage of eyes within +/-0.5 D of attempted outcome, present pain intensity (PPI) and total pain rating index (PRI(R)T) scores resulting from McGill the Pain Questionnaire, subjective symptoms, haze, and patient satisfaction. Follow-up extended to 14 months. RESULTS: There was no significant difference in UCVA (P=0.996) and percentage of eyes within +/-0.5 D of attempted correction (P=0.932). Present pain intensity and PRI(R)T scores were significantly higher in the sequential group (P=0.037; P=0.034). The percentage of satisfied patients after bilateral PRK was significantly higher in the simultaneous group (P=0.036). CONCLUSIONS: Simultaneous bilateral PRK was safe and effective, without any significant difference from sequential treatment.