David K. Wallace

Surgical results of secondary glaucomas in childhood

OBJECTIVEnThis study aimed to describe results of glaucoma surgeries performed at one institution over the past 20 years in children with aphakia, aniridia, anterior segment dysgenesis, and other secondary glaucomas.nnnDESIGNnThe study design was a retrospective review.nnnPARTICIPANTSnFifty-eight eyes of 40 patients were studied.nnnINTERVENTIONnTrabeculectomy with or without mitomycin C, Molteno implantation, goniotomy, sclerostomy, endolaser cyclophotocoagulation, and cyclocryotherapy were performed.nnnMAIN OUTCOME MEASURESnIntraocular pressure (IOP) control, defined as complete success (IOP < or = 21 without medications) or qualified success (IOP < or = 25 without medications or IOP < or = 21 with medications) and postoperative visual acuity stability were assessed.nnnRESULTSnOne hundred thirty surgical procedures were performed on 58 eyes of 40 patients; follow-up averaged 7.3 years. Intraocular pressure control was achieved in 40 (70%) of 57 eyes after 1 or more procedures. Intraocular pressure control and stabilization of visual acuity and optic disc appearance were achieved in 28 (51%) of 55 eyes. Five eyes had significant postoperative complications. Trabeculectomy with mitomycin C controlled IOP on last visit in 8 of 13 eyes with aphakic glaucoma.nnnCONCLUSIONSnSurgical intervention can control IOP and prevent visual loss in children with secondary glaucomas. In the authors experience, a filtering procedure is the most effective treatment in aphakic glaucoma and anterior segment dysgenesis.

Computer-automated quantification of plus disease in retinopathy of prematurity

BACKGROUNDnIn some cases of retinopathy of prematurity (ROP), it difficult to determine with certainty whether plus disease is present or absent. We have developed a computer program that captures digital images from a video-indirect ophthalmoscope, identifies and traces the major posterior pole blood vessels, measures the dilation and tortuosity of each vessel, and calculates whether or not an eye has plus disease. Our purpose was to determine the accuracy of the computer program in comparison with two masked examiners.nnnMETHODSnA representative sample of posterior pole images from 20 premature infants, 10 normal and 10 representing various degrees of dilation and tortuosity, was extracted from our video database and analyzed by the computer program as well as by two masked examiners experienced in the diagnosis of ROP. The standard photograph from the Cryotherapy for ROP study, representing the minimum degree of dilation and tortuosity required for plus disease, was also digitized, analyzed, and used as a numeric comparison for the automated determination of plus disease.nnnRESULTSnOf the five images determined to have plus disease by both examiners, four were calculated to have plus disease by the computer program (80% sensitivity). Of the 11 images without plus disease, 10 were calculated not to have plus disease by the computer program (91% specificity).nnnCONCLUSIONSnOur computer program has very good sensitivity and specificity compared with masked examiners determination of the presence or absence of plus disease. Automated analysis of dilation and tortuosity of posterior pole blood vessels has the potential to remove subjectivity from the determination of plus disease.

Corneal diameter in childhood aphakic glaucoma

BACKGROUNDnGlaucoma occurring after successful cataract surgery in infancy and childhood requires persistence to establish timely diagnosis and presents a therapeutic challenge. Previous studies have sought to identify risk factors, which would alert the clinician for the likelihood of developing glaucoma after cataract surgery in the young patient. Some risk factors are early age of surgery, microcornea, poor pupillary dilation, retained lens cortex, coexisting ocular anomalies, and cataract type. Other studies did not find these associations. In our experience, the majority of young aphakic glaucoma patients have microcornea. This study was carried out to investigate this association.nnnMETHODSnThe records were reviewed of all patients treated for aphakic glaucoma between 1991 and 1995 to determine the age at cataract surgery, age at glaucoma surgery, age at glaucoma diagnosis, corneal diameters, and other clinical characteristics.nnnRESULTSnForty-eight eyes in 29 patients were identified with aphakic glaucoma. Forty-five of the 48 (94%) eyes were found to have microcornea when compared with the normal corneal diameter for their age.nnnCONCLUSIONnAll children undergoing cataract surgery should have their corneal diameters recorded. Patients with corneal diameters smaller than normal should be followed closely for the development of glaucoma throughout childhood and beyond.

Ability of laboratories to detect emerging antimicrobial resistance in nosocomial pathogens : a survey of Project ICARE laboratories

A proficiency testing project was conducted among 48 microbiology laboratories participating in Project ICARE (Intensive Care Antimicrobial Resistance Epidemiology). All laboratories correctly identified the Staphylococcus aureus challenge strain as oxacillin- resistant and an Enterococcus faecium strain as vancomycin-resistant. Thirty-one (97%) of 32 laboratories correctly reported the Streptococcus pneumoniae strain as erythromycin-resistant. All laboratories testing the Pseudomonas aeruginosa strain against ciprofloxacin or ofloxacin correctly reported the organism as resistant. Of 40 laboratories, 30 (75%) correctly reported resistant MICs or zone sizes for the imipenem- and meropenem-resistant Serratia marcescens. For the extended-spectrum beta-lactamase (ESBL)-producing strain of Klebsiella pneumoniae, 18 (42%) of 43 laboratories testing ceftazidime correctly reported ceftazidime MICs in the resistant range. These results suggest that current testing generally produces accurate results, although some laboratories have difficulty detecting resistance to carbapenems and extended-spectrum cephalosporins. This highlights the need for monitoring how well susceptibility test systems in clinical laboratories detect emerging resistance.

Early strabismus surgery for thyroid ophthalmopathy

OBJECTIVEnTo determine whether strabismus surgery during active thyroid ophthalmopathy is beneficial for selected patients.nnnDESIGNnCase series.nnnPARTICIPANTSnEight patients with severe restrictive strabismus due to thyroid ophthalmopathy underwent early strabismus surgery and were followed for a minimum of 16 months after their initial surgery.nnnINTERVENTIONnAll eight patients underwent strabismus surgery while their thyroid ophthalmopathy was evolving.nnnMAIN OUTCOME MEASURESnSuccess was determined by the ability to fuse in the primary position at distance and near without an abnormal head position, and the absence of vision-threatening complications related to strabismus surgery.nnnRESULTSnAll eight patients achieved successful long-term alignment. Four patients (50%) required more than one operation.nnnCONCLUSIONSnStrabismus surgery during active thyroid ophthalmopathy can result in long-term stable alignment and may be a useful alternative in selected patients with marked disability due to thyroid ophthalmopathy.

Results of early alignment of congenital esotropia

OBJECTIVEnTo determine the long-term motor and sensory results after early surgical correction of patients with congenital esotropia.nnnDESIGNnNoncomparative interventional case series.nnnPARTICIPANTSnTen infants with congenital esotropia.nnnINTERVENTIONnPatients had bimedial rectus recession between 83 and 159 days of age; were re-examined in a regular follow-up program; and were retreated when required for strabismus, amblyopia, and refractive errors.nnnMAIN OUTCOME MEASURESnFinal alignment, stereo acuity, variations in vision, alignment, refraction, and number and types of retreatments required during the period of observation.nnnRESULTSnAll patients were aligned initially with bimedial rectus recession of 8.0 to 10.0 mm measured from the limbus. A total of 11 additional surgical procedures were performed on 7 patients to maintain alignment. Four patients required hyperopic spectacle correction to maintain alignment, and two patients required short periods of patching. Visual acuity was 20/40 or better in 19 eyes at the most recent examination, which was between 8.3 and 11.8 years after initial surgery. All patients had final alignment to within 10 prism diopters (PD) of orthotropia at either distance or near. Nine of ten patients had dissociated vertical deviation (DVD), and four of ten patients had latent nystagmus. Four patients had measurable stereo acuity at their last visit, with two achieving a stereo acuity of 3000 seconds (the Titmus fly), one 400 seconds, and one 140 seconds.nnnCONCLUSIONnSurgical alignment of congenital esotropia can be achieved in the 4-month-old with bimedial rectus recession, but this does not ensure continued alignment. At least one additional surgical procedure is required on average to maintain alignment in the first 10 years after initial successful surgery. These patients can also be expected to have one or more of the following: DVD, latent nystagmus, refractive component, or latent strabismus. Regardless of outcome, patients with congenital esotropia have optokinetic asymmetry. Attainment of stereo acuity, including high-grade stereo acuity, may be enhanced by attainment of orthotropia or small-angle esotropia but is likely to be ultimately dependent on constitutional factors rather than age of alignment.

Ocular Medications in Children

Many ocular medications are used by pediatricians or ophthalmologists caring for pediatric patients. Topical antibiotics are commonly prescribed for bacterial conjunctivitis, nasolacrimal duct obstructions, and ophthalmia neonatorum. Many new antiallergy eye drops are now available for the treatment of seasonal (hay fever) conjunctivitis. Dilating eye drops and antiglaucoma medications are generally used or prescribed by ophthalmologists, but pediatricians must be aware of their potentially serious systemic side effects. Before initiating treatment, physicians should evaluate the risks and benefits of ophthalmic medications, establish minimum dosages necessary to achieve a therapeutic benefit, and monitor children for local and systemic side effects.

Treatment outcome in fellow eyes after laser photocoagulation for retinopathy of prematurity.

PURPOSEnTo determine the concordance in structural outcome between fellow eyes in patients undergoing diode laser peripheral retinal photocoagulation for threshold retinopathy of prematurity.nnnMETHODSnRecords from 103 patients undergoing bilateral diode laser peripheral retinal photocoagulation for retinopathy of prematurity at three academic medical centers were reviewed. Information regarding infant gestational ages, birth weights, characteristics of retinopathy of prematurity, laser treatment variables, complications, and structural outcomes were obtained. The data were analyzed to determine the rate of successful structural outcomes among all eyes as well as the interocular outcome concordance.nnnRESULTSnA successful structural outcome was observed in 182 (88%) of the 206 eyes. Eighty-eight patients (85.4%) had bilateral favorable outcomes. Nine patients (8.7%) had bilateral unfavorable outcomes, and six patients (5.8%) had one favorable and one unfavorable eye. The outcome was concordant between fellow eyes in 94.2% of patients. This rate was higher than predicted if fellow-eye outcomes were truly independent (P < .00001) and did not depend on study center, laser settings, or location of the retinopathy of prematurity. Serious complications related to treatment were uncommon.nnnCONCLUSIONSnDiode laser peripheral retinal photocoagulation is a safe and effective procedure for treating threshold retinopathy of prematurity. The concordance of structural outcomes between fellow eyes is higher than expected by chance and suggests that patient-specific factors play a key role in treatment response.

Quantification of Retinopathy of Prematurity via Vessel Segmentation

Retinopathy of prematurity is a disease that affects the eyes of many babies who are prematurely born. If the retinopathy is not detected in the days following birth blindness may occur. Studies have demonstrated that by observing the blood vessels within the retina, the disease can be quantified in an early stage and early treatment can save the baby’s eyes. We have developed a new tool to assess retinopathy of prematurity. Our technique captures images of the retina to extract and quantify both tortuosity and dilation of blood vessels. Our approach demonstrates a 80% sensitivity and 92% specificity in the prediction of retinopathy compared to experts and shows a significant reduced diagnosis time and clinical integration via speech recognition and glare detection.

Surgical Management of Strabismus Associated with Chronic Progressive External Ophthalmoplegia

PURPOSEnThe purpose of the study is to describe the clinical characteristics and surgical management of strabismus associated with chronic progressive external ophthalmoplegia.nnnMETHODSnThe authors present four patients with chronic progressive external ophthalmoplegia and strabismus requiring extraocular muscle surgery, with attention to presenting symptoms, patterns of misalignment, results of surgical and nonsurgical therapies, and associated ocular or systemic conditions or both.nnnRESULTSnThree patients reported diplopia before surgery. One patient presented with an esotropia, one with an exotropia, and two with hypertropia. Three patients required only one strabismus surgery, and one patient required multiple surgeries.nnnCONCLUSIONSnChronic progressive external ophthalmoplegia may have clinical characteristics similar to those of myasthenia gravis or thyroid ophthalmopathy. Patients with chronic progressive external ophthalmoplegia and strabismus frequently have diplopia in primary position and may benefit from extraocular muscle surgery to improve alignment. In addition, because these patients typically have poor motor fusion, prisms often are useful adjuncts to surgery.