Sherwin J. Isenberg

A Controlled Trial of Povidone–Iodine as Prophylaxis against Ophthalmia Neonatorum

Background Neonatal conjunctivitis (ophthalmia neonatorum) continues to cause blindness, because the agents used prophylactically to prevent this condition are not completely effective and are not widely available in many parts of the world. Povidone–iodine ophthalmic solution is an effective antibacterial agent with broad antibacterial and antiviral activity to which no bacteria are known to be resistant, and it is far less expensive and less toxic than the agents currently used to prevent neonatal conjunctivitis. Methods We conducted a masked, prospective trial involving 3117 infants born over a period of 30 months in a hospital in Kenya. Shortly after birth each infant received a 2.5 percent solution of povidone–iodine (n = 1076), a 1 percent solution of silver nitrate (n = 929), or 0.5 percent erythromycin ointment (n = 1112) in both eyes. Randomization was achieved by rotating the three medications after each was used for a week. Results Of the neonates treated with povidone–iodine, 13.1 percent had ...

Outpatient Topical Use of Povidone-iodine in Preparing the Eye for Surgery

Povidone-iodine 5% solution placed on the eye immediately before ophthalmic surgery within the preoperative preparation significantly reduces the conjunctival bacterial flora. In 40 patients undergoing ophthalmic surgery, the authors compared the outpatient use of povidone-iodine for 3 days before surgery with a 3-day course of a combination antibiotic ophthalmic solution (Neosporin) placed on the other eye. All patients also received topical povidone-iodine on the operating table directly preceding surgery. Cultures taken just before preparation of the operative field showed a similar reduction of bacteria by each regimen. Cultures taken after preparation but before commencement of surgery showed a further reduction for both regimens, but more for eyes previously treated with the antibiotic (P less than 0.02). To minimize the conjunctival bacterial flora before surgery, the authors continue to recommend instillation of a broad-spectrum antibiotic for 3 days before surgery, followed by application of povidone-iodine solution to the eye immediately before surgery within the preoperative preparation.

A controlled trial of povidone-iodine to treat infectious conjunctivitis in children.

PURPOSE To report the efficacy of povidone-iodine as a treatment for conjunctivitis in pediatric patients. DESIGN Double-masked, controlled, prospective clinical trial. METHODS In an ophthalmology clinic in a general hospital in Manila, Philippines, 459 children (mean [SD] age 6.6 [6.6] years; range, 7 months-21 years) with acute conjunctivitis were studied. Infected eyes were cultured for bacteria and underwent immunofluorescent testing for Chlamydia trachomatis. Viral conjunctivitis was diagnosed if bacterial cultures were negative and diagnostic criteria were met. Subjects were alternated to receive povidone-iodine 1.25% or neomycin-polymyxin-B-gramicidin ophthalmic solution, one drop 4 times daily in the affected eye. Ocular inflammation was evaluated daily by the family or patient and weekly by an ophthalmologist. The main outcome measures were days until cured and proportion cured after 1 and 2 weeks of treatment. RESULTS Despite adequate statistical power (power >80% for a 1-day difference and P <.05), there was no significant difference between treatment groups regarding the number of days to cure or proportion cured at 1 or 2 weeks whether caused by bacteria or virus (P =.133-.824 for the four comparisons). After 1 week of treatment, povidone-iodine cured marginally more chlamydial infections than the antibiotic (P =.057). By 2 weeks, fewer chlamydial infections were cured than those of viral or bacterial etiology (P =.0001). The younger the patient, the faster their conjunctivitis resolved (R = 0.13, P =.013). CONCLUSIONS Povidone-iodine 1.25% ophthalmic solution was as effective as neomycin-polymyxin B-gramicidin for treating bacterial conjunctivitis, somewhat more effective against chlamydia, and as ineffective against viral conjunctivitis. Povidone-iodine ophthalmic solution should be strongly considered as treatment for bacterial and chlamydial conjunctivitis, especially in developing countries where topical antibiotics are often unavailable or costly.

Macular Development in the Premature Infant

To classify the ophthalmoscopic appearance of the developing macula, I performed retinal examinations on 129 premature neonates. In normal infants, the classification ranged from 34 weeks of gestational age when pigment was first evident in the macula, through the development of the annular ring reflex of the macula and foveolar reflex, to a mature (adult-appearing) macula at 42 weeks. This sequence allowed the observer to estimate the gestational age of the older premature neonate from the appearance of the macular area. Babies who had, or subsequently developed, retinopathy of prematurity showed a statistically significant two-week delay in macular development in the later stages. This may be the first evidence of a direct macular insult in retinopathy of prematurity.

The relationship between stereopsis and visual acuity after occlusion therapy for amblyopia

PURPOSE To investigate the relationship between visual acuity (VA) and stereoacuity after occlusion therapy in patients with various types of amblyopia. DESIGN Retrospective noncomparative case series. PARTICIPANTS Sixty-one children with amblyopia caused by anisometropia with no strabismus (26 children), small angle (</=8 prism diopters) or intermittent strabismus (20), or both (15). METHODS All were treated with occlusion therapy. Visual acuity and near stereopsis using the Titmus test (Stereo Optical Inc., Chicago, IL) were measured at each clinic visit. MAIN OUTCOME MEASURE The change in near stereopsis relative to distance VA after occlusion therapy. RESULTS Mean age at initiation of therapy was 5.1 years (range = 3.5-8) and mean follow-up 52.3 weeks (range = 13-192). Mean duration of occlusion was 36 weeks (range = 12-102). After occlusion treatment, mean VA of all children improved from 0.43 to 0.78 (P<0.0001), whereas mean stereoacuity improved from 1167.4 seconds of arc to 101 (P<0.0001). By the last visit, 85.2% (52 of 61) of patients demonstrated at least 2 lines of improvement in VA. There was a significant linear relationship between VA and stereoacuity (P<0.001). The 26 anisometropic patients without strabismus enjoyed improvement in VA and stereopsis (P<0.0001) similar to that of the 35 with small-angle or intermittent strabismus (P<0.0001). CONCLUSIONS When employing occlusion therapy for amblyopia (due to anisometropia, small-angle or intermittent strabismus, or a combination), as VA improves, stereopsis generally also improves.

Posterior fixation sutures: a revised mechanical explanation for the fadenoperation based on rectus extraocular muscle pulleys.

PURPOSE To determine the effect of the rectus extraocular muscle pulleys on the fadenoperation, an operation designed to fixate the posterior muscle belly to the underlying retroequatorial sclera. METHODS First, duction into the field of action of the operated-on muscle was quantified retrospectively after fadenoperation. Magnetic resonance imaging was then performed prospectively after surgery to verify anatomic changes. Forced duction testing was performed prospectively during surgery before and after faden placement. Finally, computed tomography in a cadaver containing radiographic markers was performed prospectively to determine the effect of fadenoperation on the position of the medial rectus insertion relative to its pulley. RESULTS Mean maximum adduction after medial rectus fadenoperation was 18 degrees (range, 10 to 25 degrees; 13 eyes). Fadenoperations combined with large medial rectus recessions restricted adduction more than fadenoperations combined with smaller recessions (P = .019), but even fadenoperations without recessions substantially restricted adduction. Mean maximum abduction after lateral rectus fadenoperation was 40 degrees (range, 25 to 45 degrees; four eyes). Axial magnetic resonance imaging in two eyes demonstrated a smaller loss of muscle tangency to the globe during contraction than predicted by geometric models. Forced ductions in nine patients performed immediately after faden placement demonstrated a new mechanical restriction to duction toward the operated-on muscle. Cadaveric computed tomographic scans demonstrated posterior displacement of the medial rectus pulley during adduction after fadenoperation. CONCLUSIONS Posterior fixation sutures do not significantly decrease muscle torque during contraction. Because posterior fixation sutures posteriorly displace the pulley sleeve during duction toward the operated-on muscle, the mechanical restriction after surgery probably represents the force deforming the pulley. This mechanical restriction may account for the limitation in duction seen after fadenoperation.

Ocular Signs of Cocaine Intoxication in Neonates

We examined 13 cocaine-intoxicated neonates, proven by urine assay, by slit lamp and found that most had iris blood vessel abnormalities. Using an iris vascularity scale that ranged from Grade 0 with no visible vessels to Grade 4 with dilated and tortuous vessels, we found that the intoxicated infants had increased grades in the iris periphery and collarette (P less than .02) as compared to 36 control newborns who had no cocaine in their urine. Infants with dilated or tortuous iris vessels were more likely to be intoxicated by cocaine (P less than .01). The presence of dilated or tortuous iris vessels in a neonate should signal the physician to rule out cocaine intoxication.

The lipid layer and stability of the preocular tear film in newborns and infants

PURPOSE To measure the thickness of the precorneal lipid layer and the stability of the precorneal tear film in neonates and infants in the first 6 postnatal months. DESIGN Prospective, observational case series. PARTICIPANTS One hundred ninety-eight neonates and infants in the newborn nursery. METHODS The Keeler Tearscope Plus (Keeler Instruments Inc., Broomall, PA) was used to evaluate lipid layer thickness by interference fringe biomicroscopy and directly to measure noninvasive tear breakup time (NIBUT). The thickness was classified from level 1 (open meshwork-very thin) to level 9 (colored fringe pattern-very thick). MAIN OUTCOME MEASURES Noninvasive tear breakup time in seconds and classification level of lipid layer thickness. RESULTS The mean lipid layer classification for all newborns was 8.3 +/- 0.9, with no significant difference between genders. The thickest classifications (levels 8 and 9) were found in 83.3% of all infants. At 3 and 6 postnatal months, all infants studied had a lipid layer classification of 9. Mean NIBUT was 32.5 +/- 5.2 seconds (range, 17.6-48.5 seconds) and was not significantly different whether stratified by race, postconceptional age, or birthweight. However, although NIBUT was longer in males at birth (35.1 +/- 4.2 seconds versus 29.4 +/- 4.5 seconds; P < 0.001), it was equal in both genders at 3 and 6 postnatal months. CONCLUSIONS In the first 6 postnatal months, the lipid layer of the tear film is much thicker than in adults. The NIBUT in newborns is prolonged compared with adult values. This thick lipid layer in infants provides stability that may help prevent the thin aqueous layer from evaporating.

The Effect of Anterior Transposition of The Inferior Oblique Muscle

The effect of anterior transposition of the insertion of the inferior oblique muscle was compared with the results from conventional inferior oblique muscle recession in 50 patients. Even though both groups of patients had a similar degree of overaction preoperatively, postoperative inferior oblique muscle action was weaker (P < .01) and upgaze more limited P < .01) in the anterior transposition group. These data suggest that anterior transposition serves to convert the inferior oblique muscle from an elevator to a depressor on attempted elevation. Because anterior transposition is such a powerful weakening operation, we suggest that it be reserved for patients with moderate to severe inferior oblique muscle overaction. To avoid postoperative hypotropia in upgaze, anterior transposition should be performed in both eyes for bilateral inferior oblique muscle overaction and not unilaterally.

A randomized clinical trial of the nonsteroidal eyedrop diclofenac after strabismus surgery1

OBJECTIVE This study aimed to compare the anti-inflammatory and analgesic effects of topical diclofenac sodium 0.1% (Voltaren) with prednisolone sodium phosphate 1% ophthalmic solution after strabismus surgery. DESIGN A prospective, double-masked, randomized, two-center clinical trial. PARTICIPANTS Eighty eyes of 52 patients undergoing strabismus surgery were examined. INTERVENTION For 1 week after surgery, the eye that was operated on received one drop of either diclofenac or prednisolone four times a day. MAIN OUTCOME MEASURES The diclofenac- and prednisolone-treated eyes were compared on postoperative days 3 and 7 with respect to signs of inflammation (e.g., erythema, edema, discharge), patient comfort, and conjunctival incisional healing. RESULTS On postoperative day 7, in eyes that received prednisolone, the conjunctival defects were larger (P = 0.004) and more frequent (P = 0.02). For all subjects, despite adequate statistical power, there was no statistically significant difference in inflammatory scores between eyes that received diclofenac or prednisolone. In cases of bilateral surgery, however, there was less postoperative erythema and edema in the diclofenac-treated eyes. CONCLUSIONS In the first week after strabismus surgery, topical diclofenac proved at least as effective as prednisolone in controlling inflammation and discomfort with less delay in incisional wound healing. Topical diclofenac, a nonsteroidal anti-inflammatory agent, may be considered for use after strabismus surgery in place of corticosteroids.