Randomized Clinical Trial on the Efficacy and Side Effects of Tropicamide and Phenylephrine in Mydriasis for Ophthalmoscopy

Purpose

To compare the efficacy and side effects of two combinations of tropicamide and phenylephrine as mydriatics for ophthalmoscopy.

Methods

In this prospective randomized controlled trial, 51 Chinese outpatients were randomized to receive topical tropicamide 1.0% and phenylephrine 2.5% (Regime A), and 50 to receive a fixed combination of tropicamide 0.5% and phenylephrine 0.5% (Regime B). The change in horizontal pupillary diameter, subject discomfort upon instillation and the time elapsed between instillation and recovery from glare and near blur were studied.

Results

After 60 minutes, the mean increase in pupillary diameter was 3.56±0.65 mm with Regime A, and 3.04±0.62 mm with Regime B (P<0.01), but there was no difference in the proportion of subjects having a post-mydriatic pupillary diameter of 6 mm or larger (P=0.54). No subjects required additional instillation. Regime B was better tolerated (P<0.001). The median times elapsed between instillation and recovery from glare or near blur was 7 hours, without a significant difference between the two regimes (P=0.5).

Conclusions

Both regimes were effective and safe for ophthalmoscopy. However, Regime B was better tolerated. Subjects may be reassured that the side effects of glare and near blur are likely to disappear by the following day.

Study of the efficacy of toothpaste containing casein phosphopeptide in the prevention of dental caries: a randomized controlled trial in 12- to 15-year-old high caries risk children in Bangalore, India

Casein phosphopeptide (CPP) has the potential to be added to mouth rinses, gels, toothpastes, chewing gums and confectioneries. Until now CPP has been studied in vitro, in situ and in animals, but clinical trials are lacking. This study was conducted to evaluate the efficacy of CPP-containing toothpaste in preventing dental caries in schoolchildren. The study was conducted among 150 schoolchildren randomly divided into three groups, each using one of three types of toothpastes: (a) containing 2% w/w CPP; (b) containing 1,190 mg/kg fluoride as 0.76% sodium monofluorophosphate (SMFP); (c) placebo toothpaste without CPP or fluoride. Students brushed with the given toothpastes for 24 months. Oral hygiene and caries experience were assessed at baseline, 12 and 24 months. The increments in caries lesions were calculated and analyzed to assess the caries-preventive effect. A significant reduction in caries increment was observed among students using CPP toothpaste or SMFP toothpaste, compared with the group using the placebo toothpaste. The reduction in caries increment was not significantly different between the CPP and SMFP groups. Oral Hygiene Index score increased from the 12-month to the 24-month examination. It is concluded that CPP can be effectively incorporated into calcium carbonate-based toothpaste and that toothpaste containing CPP is effective in preventing caries. Toothpaste containing 2% CPP seemed to have an efficacy similar to paste containing 1,190 mg/kg SMFP in the prevention of caries.

Unilateral ptosis correction with mersilene mesh frontalis sling in infants: thirteen-year follow-up report

PURPOSE

To assess surgical, visual, refractive, and aesthetic outcomes 13 years after mersilene mesh frontalis sling (MMFS) operation for severe unilateral congenital ptosis performed in 10 infants before 1 year of age.

METHODS

Longitudinal follow-up of an interventional case series by structured ocular examinations, external photographs, and questionnaire-based interviews.

RESULTS

Mean age at surgery was 6.9+/-2.7 months. After a mean follow-up of 13.0+/-0.6 years, one patient (10%) had recurrent ptosis with the upper lid 2 mm below the superior limbus at 3 months postoperatively. Best-corrected visual acuities were within two Snellen lines between the two eyes in all patients. Astigmatic errors were 1.20+/-1.00 D and 1.10+/-1.70 D between operated and unoperated eyes. Four patients had 2 mm lid lag on down-gaze and one of them had 2 mm lagophthalmos. Mean satisfaction scores (scale of 1 to 100) for lid position, cosmesis, function, and to the procedure were 83.3+/-11.8, 77.0+/-22.9, 89.4+/-5.5, and 86.8+/-6.3, respectively. No case of overcorrection, sling extrusion, stitch granuloma, or exposure keratopathy was noted.

CONCLUSIONS

In view of the low recurrence rate (10%) and absence of serious complication or need for revision after 13 years, the use of MMFS seems effective and feasible in infants less than 1 year old. Achieving compatible long-term stability, satisfactory aesthetic, and visual outcomes, MMFS may offer an alternative to delaying operations for autogenous fascia lata harvesting in infants requiring early ptosis correction.

Posterior corneal curvature measurements with peripheral fitting zones before and after myopic LASIK using Orbscan II

PURPOSE

To compare pre- and postoperative posterior corneal curvature measurements in peripheral fitting zones using the Orbscan II topographer in patients undergoing myopic LASIK.

METHODS

Retrospective analysis of preoperative and 3-month postoperative Orbscan II data of 194 eyes that underwent myopic LASIK at a university eye center. Posterior corneal power was estimated using the peripheral 7- to 10-mm fitting zones. The pre- and postoperative values were analyzed and compared.

RESULTS

The mean difference in estimated pre- and postoperative power of the posterior cornea was -0.04 +/- 0.16 diopters (P < .01).

CONCLUSIONS

The difference in posterior corneal curvature measurement following myopic LASIK using the peripheral fitting zone with the Orbscan II, as compared to the preoperative values, is clinically insignificant.

Descemet stripping endothelial keratoplasty: effect of the surgical procedure on corneal optics

PURPOSE

To determine the changes in corneal optical performance after posterior lamellar corneal transplantation.

DESIGN

Retrospective case series.

METHODS

The anterior segment in four eyes of four patients who underwent Descemet stripping endothelial keratoplasty (DSEK) with cataract extraction and intraocular lens (IOL) implantation were imaged with the Visante anterior segment optical coherence tomography [OCT] (Carl Zeiss Meditec, Dublin, California, USA). The curvature of the posterior surface of the donor graft was compared with that of the host cornea, and corneal thickness was measured.

RESULTS

All eyes had a hyperopic refractive error after surgery. The posterior corneal curvature after surgery was more than that before surgery. Average preoperative keratometry was 43.4 diopters (D), and after surgery, it was 42.8 D using keratometry. However, when the postsurgical corneal power was calculated using the Gaussian optics method, the average value was 40.8 D.

CONCLUSIONS

The addition of a donor corneal graft to the posterior surface of decompensated corneas may lessen the effective optical power of the cornea and may have implications for IOL power calculations in these eyes.

Calculating graft size and position in rotational corneal autografting: a simplified approach

In eyes with eccentric corneal opacities partially involving the pupillary area, using a rotational corneal autograft, can help restore vision without the immunological complications associated with allografts. In this report, we describe a simple intraoperative method for determining trephine size and placement for rotational corneal autografting. This surgical approach helps in the planning and execution of rotational corneal autografting, to obtain good outcomes.

The effect of parental history of myopia on children's eye size and growth: results of a longitudinal study

PURPOSE

To evaluate the effect of parental myopia on eye size and growth in Chinese children.

METHODS

A school-based, cross-sectional survey was performed in Chinese children 5 to 16 years of age. A longitudinal cohort study was conducted 1 year later. The effects of parental myopia, parental education level, and near work performed by the child on the refractive error and ocular biometry of the child were assessed.

RESULTS

There were 7560 children enrolled in the initial study (response rate: 76.3%). One year later, 4468 children (response rate: 75.9%) in the original cohort (with the exception of those who had completed primary schooling) were evaluated, to determine eye growth. Although children with a stronger parental history of myopia tended to be less hyperopic before the onset of myopia (spherical equivalent refraction [SER] = 0.43 D, 0.67 D, and 0.68 D in children with two, one, and no myopic parents respectively; P = 0.007), the axial lengths did not follow the same pattern (axial length [AL] = 23.11, 23.07, and 23.15 mm; P = 0.429). Eye growth and myopic shift in refraction occurred more rapidly among children with a stronger parental history of myopia (annual AL growth/myopia progression = 0.37 mm/-0.22 D, 0.26 mm/-0.07 D, and 0.20 mm/-0.02 D in children with two, one, and no myopic parents, respectively; P < 0.001).

CONCLUSIONS

Ocular biometric data in Chinese children suggest that parental history of myopia influences the growth rate of the eye, rather than its size before the onset of myopia, as previously reported in Caucasian children. Further longitudinal studies involving children of different ethnicities are warranted.

Monocular blindness due to central retinal artery occlusion in bipolar hemireplacement arthroplasty of the hip

Though rare, perioperative loss of vision after non-ocular surgeries is a disastrous complication. This has been reported after spine surgery or cardiopulmonary bypass surgery. We present an otherwise healthy 54-year-old man who underwent bipolar hemireplacement for a fractured neck of femur, and developed perioperative monocular visual loss due to central retinal artery occlusion, a complication hitherto unreported in hip replacement surgeries. The possible aetiological factors and the measures to prevent this complication are discussed.

Anterior segment ischemia after two-muscle surgery in a patient with radiation-treated nasopharyngeal carcinoma

Anterior segment ischemia after strabismus surgery is a rare occurrence. Risk factors include single-stage surgery of three or more muscles in one eye, dysthyroid eye disease, and advanced age. The authors report a case of anterior segment ischemia after single-stage surgery of two horizontal muscles without previous reported risk factors. However, the patient had received radiotherapy for nasopharyngeal carcinoma more than 20 years ago. The case was successfully treated with systemic steroids but with reduced best-corrected visual acuity. Previous radiotherapy in the related orbital field may be a new risk factor for this condition.

Agreement among 3 Methods to Measure Corneal Thickness: Ultrasound Pachymetry, Orbscan II, and Visante Anterior Segment Optical Coherence Tomography

PURPOSE

To assess the agreement of central and paracentral corneal thickness measurements between ultrasound pachymetry (USP), Orbscan II, and Visante anterior segment optical coherence tomography (ASOCT).

DESIGN

Observational cross-sectional study.

PARTICIPANTS

Seventy eyes of 70 subjects.

METHODS

Each subject underwent Orbscan II (using an acoustic equivalent correction factor of 0.89), ASOCT, and USP examination. Bland-Altman plots were used to evaluate agreement between instruments.

MAIN OUTCOME MEASURES

Central and paracentral corneal thickness measurements by the 3 methods and agreement, as evaluated by 95% limits of agreement (LOA).

RESULTS

The mean measurements of average central corneal thickness by USP, Orbscan II, and ASOCT were 553.5+/-30.26 microm, 553.22+/-25.47 microm, and 538.79+/-26.22 microm, respectively. There was high correlation between instruments: USP with ASOCT (r = 0.936, P<0.001), USP with Orbscan II (r = 0.900, P<0.001) for central corneal thickness measurements, and Orbscan II with ASOCT for average paracentral 2- to 5-mm measurements (r = 0.947, P<0.001). The mean differences (and upper/lower LOA) for central corneal thickness measurements were 0.31+/-13.34 microm (26.44/-25.83) between USP and Orbscan II, 14.74+/-10.84 microm (36.0/-6.51) between USP and ASOCT, and 14.44+/-9.14 microm (32.36/-3.48) between Orbscan II and ASOCT. The average mean difference (and upper/lower LOA) between Orbscan II and ASOCT for paracentral 2- to 5-mm corneal thickness measurements was 10.35+/-8.67 microm (27.35/-6.65).

CONCLUSION

Anterior segment optical coherence tomography underestimated corneal thickness compared with that measured with USP. Anterior segment optical coherence tomography had better agreement with the gold standard USP, as compared with Orbscan II. However, important discrepancies among instruments exist. Clinicians should be aware that corneal thickness measurements are influenced by the method of measurement and that, although highly correlated, these instruments should not be used interchangeably for the assessment of corneal thickness.

Accuracy of Orbscan II in the Assessment of Posterior Curvature in Patients With Myopic LASIK

PURPOSE

To evaluate the accuracy of Orbscan II measurements in assessing posterior corneal curvature in patients undergoing myopic LASIK.

METHODS

Using the Orbscan II, posterior corneal curvature was assessed pre- and postoperatively in 304 eyes that underwent myopic LASIK. The radius of curvature and corneal refractive power in diopters (D) were compared using the paired sample t test.

RESULTS

The mean pre- and postoperative radius of posterior corneal curvature were 6.49 +/- 0.26 mm and 6.35 +/- 0.30 mm, respectively. Mean pre- and postoperative posterior corneal power were -6.17 +/- 0.25 D and -6.32 +/- 0.30 D, respectively, and the difference (0.14 +/- 0.14 D) was statistically significant (P < .01).

CONCLUSIONS

Although the derived value for the power of the postoperative LASIK posterior corneal surface is overestimated using the Orbscan II, this small difference may not be clinically important. Orbscan II measurements can therefore be used (with caution) to measure posterior corneal curvature in patients with myopic LASIK for the assessment of intraocular lens power based on the Gaussian optics formula.

Topical anesthesia-induced keratopathy after laser-assisted subepithelial keratectomy

A 42-year-old woman had uneventful bilateral laser-assisted subepithelial keratectomy (LASEK) to correct myopia. She experienced intense pain in the first postoperative week and obtained topical oxybuprocaine for pain relief. Subsequently, she developed bilateral persistent corneal epithelial defects, epithelial edema, and bullae that failed to heal with bandage contact lens and topical lubricants. Over the next 4 months, there was progressive corneal stromal thinning and descemetocele formation in 1 eye, requiring application of cyanoacrylate glue, and stromal edema and scarring in the other eye, which resulted in a visual acuity of counting fingers. Investigations did not reveal associated infection or an underlying immunological disorder; however, the patient admitted to excessive use of topical anesthetic eyedrops in the post-LASEK period. She subsequently had penetrating keratoplasty and lens extraction with IOL implantation in the right eye. The left eye healed with central corneal scarring. This case illustrates that serious sight-threatening complications may occur after LASEK due to abuse of topical anesthetic agents.

Central corneal thickness measurements using Orbscan II, Visante, ultrasound, and Pentacam pachymetry after laser in situ keratomileusis for myopia

PURPOSE

To compare corneal pachymetry assessment using 4 measurement methods in eyes after laser in situ keratomileusis (LASIK) for myopia.

SETTING

Department of Ophthalmology & Visual Sciences, The Chinese University of Hong Kong, Hong Kong Eye Hospital, Hong Kong SAR.

METHODS

Fifty-two consecutive patients (103 eyes) who had LASIK for the correction of myopia had Orbscan II (Bausch & Lomb), Visante (Carl Zeiss Meditec), Pentacam (Oculus, Inc.), and ultrasound (US) pachymetry (Sonomed, 200P) 6 months after surgery. Data were analyzed using the paired sample t test, Bland-Altman plots, and linear regression.

RESULTS

The mean postoperative pachymetry measured by US, Orbscan (0.89 acoustic factor), Pentacam, and Visante pachymetry were 438.2 microm+/-41.18 (SD), 435.17+/-49.63 microm, 430.66+/-40.23 microm, and 426.56+/-41.6 microm, respectively. Compared with the US measurement, Pentacam and Visante measurements significantly underestimated corneal thickness by a mean of 7.54+/-15.06 microm (P<.01) and 11.64+/-12.87 microm (P<.01), respectively. There was no statistically significant difference between US and Orbscan measurements.

CONCLUSION

Pentacam and Visante measurements of corneal thickness 6 months after LASIK were significantly less than those obtained using Orbscan and US pachymetry, although all 4 measurement methods showed a high correlation with each other.

Repositioning of Free Cap Four Days After LASIK

PURPOSE

To report management and outcome of late repositioning of flap dislodgement after LASIK.

METHODS

A 27-year-old man underwent LASIK in the right eye for correction of myopia, which was complicated by free cap. The flap was repositioned, but dislodged 2 days later. The dislodged flap was stored in balanced salt solution for 48 hours and repositioned 4 days after initial surgery.

RESULTS

Postoperatively, the flap remained apposed, but diffuse lamellar keratitis and epithelial ingrowth developed, which was managed with topical steroids and topical mitomycin C. Stromal haze gradually decreased by 16 months postoperatively, resulting in best spectacle-corrected visual acuity of 20/20.

CONCLUSIONS

Flap dislodgement > 48 hours postoperatively can be repositioned with good visual outcome. The flap should be preserved in the event of such complication.

Perilimbal conjunctival pigmentation in Chinese patients with vernal keratoconjunctivitis

PURPOSE

To document the disease spectrum and evaluate the presence of perilimbal conjunctival pigmentation in Chinese patients with vernal keratoconjunctivitis (VKC).

METHOD

A case-control study was conducted between November 2004 and July 2005. Patients aged 18 or younger with VKC and age-matched children attending our eye clinic for refractive or orthoptic problems were recruited and compared. Detailed slit-lamp examination was performed noting in particular the presence of perilimbal conjunctival pigmentation, the severity of papillary reaction, and corneal complications of VKC.

RESULTS

A total of 19 patients and 23 controls were evaluated. The presence of bilateral large tarsal or limbal papillae and epithelial defect were significantly associated with symptoms severity (Fisher's exact test, P=0.015 and P=0.035 respectively). All VKC patients were found to have perilimbal conjunctival pigmentation in at least one eye. There was a significant correlation in the colour and density of pigments between the two eyes (Sperman's rho=0.93, P<0.001). None of the controls was found to have such perilimbal conjunctival pigmentation (Fisher's exact test, P<0.001).

CONCLUSION

The presence of perilimbal conjunctival pigmentation appears to be a consistent clinical finding in Chinese patients with VKC and may be a useful diagnostic sign for patients with subtle signs or symptoms.

Uncemented primary press-fit total hip arthroplasty: a 3 to 6 years of experience

PURPOSE

To analyse the 3 to 6 years' clinicoradiological outcome of 45 uncemented total hip arthroplasties performed in 37 patients using cementless Spotorno stem and St Nabor cup.

METHODS

The main indications for surgery were avascular necrosis of the femoral head and rheumatoid arthritis. Younger patients with good bone quality and a trumpet-shaped femur were eligible. A single surgeon performed all the operations using a posterolateral approach. Patients were reviewed at 6 weeks, 3 months, 6 months, and yearly thereafter. The clinical status was recorded using the Harris Hip Score. All radiographs were analysed by 2 independent blinded observers on 2 separate occasions.

RESULTS

The mean follow-up period was 49 months and the mean Harris Hip Score at the latest follow-up was 94. Osseointegration in the form of trabeculae running from the endosteum to the prosthesis surface along with tropism of the calcar was evident in 73% of the hips. None of the remaining hips showed any continuous radio-opaque lines suggestive of a lack of bone ongrowth. Patients with endosteal condensation had better Harris Hip Scores. Intra-operative stability of the implants could fairly predict outcome.

CONCLUSION

Initial clinicoradiological results of uncemented total hip arthroplasty are promising in younger patients with good bone quality and a trumpet-shaped femur.

Medial collateral ligament avulsion from both tibial and femoral attachments: a case report

The medial collateral ligament (MCL) is the most commonly injured ligament of the knee joint. Proximal MCL tears occur more frequently than do distal ones. We report a 28-year-old man with a valgus injury of his left knee joint after a fall from a motorcycle. Magnetic resonance imaging of the affected knee joint revealed complete avulsion of the superficial MCL from both its femoral and tibial insertions. The meniscofemoral portion of the deep part of the MCL was also torn and the medial meniscus was subluxated. Such a pattern, an MCL tear with subluxation of the medial meniscus, is rare.

Polyglactin sutures versus nylon sutures for suturing of conjunctival autograft in pterygium surgery: a randomized, controlled trial

PURPOSE

To compare the use of polyglactin sutures versus nylon sutures for conjunctival autograft suturing in pterygium surgery.

METHODS

A prospective, randomized, controlled, clinical trial was conducted, in which 32 eyes of 32 patients with primary nasal pterygium were randomized to undergo pterygium surgery with the use of nylon sutures or polyglactin sutures for conjunctival autograft suturing. Patients were followed up for 3 months. Outcome measures included postoperative discomfort according to a visual analogue scale (VAS), graft hyperaemia, graft oedema and tarsal conjunctival papillary reaction.

RESULTS

There was no significant difference in the postoperative discomfort as assessed by VAS in both groups at all follow-up visits. Patients who had polyglactin sutures for suturing conjunctival autograft were noted to have more tarsal conjunctival papillary reaction at day 1 (p = 0.01) and more graft hyperaemia at week 1 (p = 0.019) after the operation. At 4 weeks postoperatively, significantly more nylon sutures remained on the autograft (p = 0.021), some of which were buried and could not be removed.

CONCLUSIONS

Both polyglactin and nylon are effective suture materials for autograft suturing in pterygium surgery and cause comparable postoperative discomfort. Polyglactin sutures resulted in slightly more conjunctival reaction in the early postoperative period compared with nylon sutures.

Topical Atropine in Retarding Myopic Progression and Axial Length Growth in Children with Moderate to Severe Myopia: A Pilot Study

PURPOSE

To study the safety and efficacy of topical 1% atropine eye ointment in retarding myopic progression in children with moderate to severe myopia.

METHODS

This was an interventional control study. Children (aged 5-10 years) with myopia of -3.00 diopters (D) or more were treated with 1% atropine ointment once daily for 1 year. Baseline and regular assessments of refractive errors by cycloplegic autorefraction and of axial length were done by ultrasound biometry, and the results were compared with data of control subjects.

RESULTS

Twenty-three children (mean age: 7.4 +/- 1.6 years) with moderate to severe myopia, being treated in the Hong Kong Eye Hospital of the Chinese University of Hong Kong, were recruited into the atropine group, and 23 children from the same eye clinic were matched with the study subjects with respect to age, sex, and initial spherical equivalent refraction, as controls. The initial refractive errors were -5.18 +/- 2.05 D and -5.12 +/- 2.33 D in the atropine and the control groups, respectively (P = 0.934). Myopic progression was significantly less (P = 0.005) in the atropine group (+0.06 +/- 0.79 D) than in the control group (-1.19 +/- 2.48 D). Axial length increase was also significantly smaller in the atropine group (0.09 +/- 0.19 mm) than in the control group (0.70 +/- 0.63 mm) (P = 0.004). One child (4.3%) developed an allergic reaction. No other major adverse effects related to the treatment were noted.

CONCLUSION

Topical 1% atropine ointment is a safe and effective treatment for retarding myopic progression in moderate to severe myopia. Further large-scale randomised controlled study with longer follow-up seems warranted.

Corneal Endothelial Cell Density and Morphology in Healthy Chinese Eyes

PURPOSE

To describe corneal endothelial cell density and morphology in healthy Chinese eyes.

METHODS

Specular microscopy was performed in 1329 eyes of 700 healthy volunteers (M:F, 311:389), 10 to 98 years of age. Parameters studied included endothelial cell density (CD), cell area (CA), coefficient of variation (CV) in cell area, and percent hexagonality.

RESULTS

Mean endothelial CD in the study population was 2932 +/- 363 cells/mm2. There was a statistically significant decrease in endothelial CD (P < 0.001; correlation, -0.435) and percentage of hexagonal cells (P < 0.001; correlation, -0.241) with age. Mean CA, CV, and percentage of hexagonal cells were 347 +/- 46 microm2, 33 +/- 5, and 59% +/- 9%, respectively. There was also a statistically significant increase in CA (P < 0.001; correlation, 0.410) and CV (P < 0.001; correlation, 0.251) with increasing age.

CONCLUSIONS

Normative data for the endothelium in the Chinese population are reported. Our data add to the knowledge about endothelial cell parameters in Chinese eyes and serve as a baseline for comparative studies with other populations.

Desmoplastic round cell tumour of the abdomen

Desmoplastic round cell tumour is a very rare tumour of childhood and young adults, and is not usually suspected as an explanation of intraabdominal or pelvic tumour. We report two cases of desmoplastic round cell tumour of the abdomen in the paediatric age group, occurring in two boys, an 11-year-old and a 13-year-old. We aim to demonstrate the imaging findings and to emphasise the importance of including this tumour in the differential diagnosis of childhood intraabdominal and pelvic tumours.