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At least 919 records · Page 51Linked to original sources

PubMed2001

The use of subtenon ropivacaine in managing strabismus with adjustable sutures.

BACKGROUND: Squint angle alterations with the use of adjustable sutures after strabismus surgery can be painful. Ropivacaine is a long-acting local anesthetic that, at low doses, produces sensory block with limited nonprogressive motor block. METHOD: We performed a double-blind, randomized, pilot study using subtenon ropivacaine or placebo at the time of surgery in patients undergoing adjustable suture surgery. Surgery was performed by the same surgeon in each case. Later in the day, the same surgeon adjusted the sutures. At the time of adjustment, the patient recorded pain using a linear pain score, and the surgeon recorded ease of adjustment using a linear score. The results of surgery were noted at 4 weeks. RESULTS: Ten patients were randomized to receive ropivacaine and 11 to receive placebo. All 10 of the ropivacaine group and 9 of the placebo group had suture adjustment. In the ropivacaine group, there was a significantly lower pain score (P <.05, Mann-Whitney U test) but no significant difference in ease of adjustment. There appeared to be no demonstrable difference in the results of surgery between the 2 groups. CONCLUSION: Ropivacaine appears to reduce the pain of postoperative suture adjustment without adversely affecting the final outcome, although it does not appear to ease the adjustment itself. This small pilot study shows promising results in postoperative analgesia in these patients, although further larger trials are recommended.

Adult↗

PubMed2002

The reliability of grading the fixation preference test for the assessment of interocular visual acuity differences in patients with strabismus.

PURPOSE: The purpose of this study is to test the reliability of the grading system of standard fixation preference testing compared with the logarithmic scale of the minimum angle of resolution (logMAR) interocular visual acuity difference of patients with manifest strabismus and to test the strength of association between the interocular visual acuity difference and the grade of alternation. METHODS: A total of 111 strabismic patients with large angle heterotropias (> 10 PD) were included in this study. The visual acuities of these patients were determined using the Snellen's, tumbling E, or Lea visual acuity charts as appropriate for the child's age and ability to cooperate. The results were converted to their logarithmic equivalents of minimum angle of resolution or recognition. Fixation preference was graded from 0 to 4 and was evaluated by observing the time-period through which fixation was maintained with the nonpreferred eye. RESULTS: The median value of interocular visual acuity difference for grade 4 was determined as 0.0, grade 3 as 0.097, grade 2 as 0.17, grade 1 as 0.3, and grade 0 as 0.8. The grade of fixation preference was found to be inversely related to the logMAR interocular visual acuity difference (P <.0001). There was a significant difference between every fixation grade except grade 1 and grade 2 (P <.005). CONCLUSIONS: The grades used in fixation preference testing correlate with the logMAR visual acuity differences in strabismic amblyopic patients. However, the grading system does not imply a linear function in terms of visual acuity difference. The difference between the logMAR values of patients with grade 0 and 1 are more profound compared with other grades.

Adolescent↗

PubMed2002

Investigation of hemodynamic changes after strabismus surgery using color Doppler imaging.

PURPOSE: To investigate hemodynamic changes after strabismus surgery using color Doppler imaging (CDI). METHOD: Group 1 patients (n = 13) underwent surgery on a single horizontal rectus muscle, and group 2 (n = 13) underwent surgery on both horizontal rectus muscles. Subjects with no systemic or ophthalmologic disorders were selected as controls (n = 16). In group 1 and group 2, CDI of the ophthalmic artery (OA), the central retinal artery (CRA), and the nasal and temporal posterior ciliary arteries (PCAs) was performed before surgical correction and on postoperative days 1 and 7. For each vessel, peak systolic (V(max)), end diastolic (V(min)), and mean (V(mean)) blood flow velocities were measured, in addition to the resistivity index (RI) and pulsatility index (PI). RESULTS: V(max) in the OA on postoperative day 1 was higher in group 2 than in group 1 (P =.004). V(min) in the OA on postoperative day 1 was significantly higher in group 2 than in the controls (P =.001) and group 1 (P =.001). For group 2, comparison of the OA preoperative findings to the findings on postoperative day 1 showed that V(min) (P =.003) and V(mean) (P =.02) increased significantly, and the RI (P =.01) and PI (P =.006) decreased significantly. These significant differences were not observed on day 7 (P >.05). CONCLUSION: Surgery on both horizontal rectus muscles in an eye causes hemodynamic changes in the OA in the early postoperative period.

Adolescent↗

PubMed2002

Visual and perceptual characteristics, ocular motility and strabismus in children with periventricular leukomalacia.

The immature visual system is vulnerable to adverse events. Periventricular leukomalacia (PVL), an end-stage lesion after hypoxia-ischemia at gestational age 24-34 weeks affecting the visual radiation, has become a principal cause of visual impairment in children. Cerebral visual dysfunction caused by PVL is characterized by delayed visual maturation, subnormal visual acuity, crowding, visual field defects, and visual perceptual-cognitive problems. Magnetic resonance imaging is the method of choice for diagnosing this brain lesion, which is associated with optic disk abnormalities, strabismus, nystagmus, and deficient visually guided eye movements. Children with PVL may present to the ophthalmologist within a clinical spectrum from severe visual impairment in combination with cerebral palsy to only early-onset esotropia, normal intellectual level and no cerebral palsy. Optimal educational and habilitational strategies need to be developed to meet the needs for this group of children.

Adolescent↗

PubMed2002

Neuroanatomical and neurophysiological consequences of strabismus: changes in the structural and functional organization of the primary visual cortex in cats with alternating fixation and strabismic amblyopia.

In recent years, evidence has accumulated indicating that long-ranging neuronal connections within the primary visual cortex (area 17) mediate the influences of context and experience, possibly also those of expectation. After early onset strabismus, the layout of these connections is massively modified: in strabismic but not in normally raised cats, horizontal connections extend primarily between neurons activated by the same eye. As a possible consequence of the modified circuitry, neuronal synchronization between different ocular dominance domains is also massively reduced. Thus, the inability of strabismics to combine the signals arriving from the two eyes into a single percept may be caused by these structural and functional changes. Strabismic amblyopia is also accompanied by significant modifications of intracortical associational interactions: corresponding to the psychophysical deficits, neurons driven by the normal eye displayed stronger synchronization of their responses than neurons dominated by the amblyopic eye.(1) These data demonstrated for the first time a clear neurophysiological correlate of strabismic amblyopia in area 17. They suggest that - similar to our observations in divergent squinters - at least some of the perceptual deficits of amblyopic patients are due to experience-dependent changes in intracortical circuitry. We analyze this question by combining optical imaging of intrinsic signals with 3-D reconstructions of neuronal circuitry.

Amblyopia↗

PubMed2005

Single-stage adjustable strabismus surgery under topical anesthesia and propofol.

AIM: To present our experience with single-stage adjustable strabismus surgery (SSASS) under topical anesthesia and propofol. MATERIALS AND METHODS: Sixteen patients who either had diplopia before the surgery or were at risk of developing diplopia after the surgery were selected for this operation after evaluating their tolerance for an eyelid speculum. Recession of the lateral recti, recession, resection and advancement of the medial recti, anteriorization of the inferior oblique and marginal myotomy to the superior rectus were the procedures done under topical anesthesia and propofol. The operations were done in two phases; in the first phase, the patients were sedated for 10 minutes with intravenous propofol (2 mg/kg) and the operation was done under topical anesthesia with 2% lidocaine. In the second phase, the patients were conscious and the adjustments were made. RESULTS: None of the patients complained of significant pain during the surgery. No complications occurred during and after the procedure and no patients had diplopia during the postoperative follow-up. CONCLUSIONS: Single-stage adjustable surgery is practical and avoids the risks of regional and general anesthesia. The only disadvantage is the pain that some patients experience. We found that it is feasible to use propofol for this surgery; it provides deep sedation and prevents pain from being felt during the operation, and its short elimination half-life provides rapid awakening for the adjustment phase.

Adolescent↗

PubMed2005

Strabismus and binocular functions in a sample of Swedish children aged 4-15 years.

PURPOSE: To investigate strabismus, head posture, nystagmus, stereoacuity, ocular motility, near point of convergence (NPC) and accommodative convergence to accommodation ratio (AC/A) in a sample of Swedish children. METHODS: A prospective cross-sectional study was carried out on 143 children, 4-15 years of age. RESULTS: Heterotropia was found in five children (3.5%), four with esotropia and one with exotropia. One child with esotropia had a slight overaction of both inferior oblique muscles. Heterophoria was found in 37 children (26%) at near and/or distance fixation and it was four times more common at near than at distance. In 29 children, heterophoria was found at one distance only and orthophoria at the other. Orthophoria at both near and distance fixation was noted in 101 children (70.5%). The near point of convergence was < or =6 cm in 97% of the children and 97% had stereoacuity of 60" or better. In the whole group, the median AC/A ratio calculated with the heterophoria method was 5.6/1 prism diopters/diopters (PD/D) and with the gradient method, 1.3/1 PD/D. No anomalous head postures or nystagmus were observed and all children had normal versions. CONCLUSION: In this study, 143 well-defined children were investigated with a battery of accurately described tests, commonly used in clinical practice. These results are in agreement with those of other studies examining one or few variables in larger populations and the authors therefore conclude that their results may be used for comparisons with different patient groups.

Adolescent↗

PubMed1985

Comparison of four non-depolarizing neuromuscular blocking drugs in the suppression of the oculocardiac reflex during strabismus surgery in children.

Eighty children (aged 2-12 yr) undergoing strabismus surgery were randomly assigned to receive tubocurarine, alcuronium, pancuronium or vecuronium during anaesthesia with thiopentone, fentanyl and nitrous oxide in oxygen. Heart rate and rhythm were recorded before and after the induction of anaesthesia and before and during traction on an extraocular muscle. End-tidal carbon dioxide concentration and the degree of neuromuscular blockade were monitored. Alcuronium seemed to give more protection against the oculocardiac reflex (defined as a 20% decrease in heart rate) than did tubocurarine, pancuronium or vecuronium.

Alcuronium↗

PubMed1994

Comparison of the analgesic and emetic properties of ketorolac and morphine for paediatric outpatient strabismus surgery.

In a prospective, double-blind, randomized study, we have compared i.v. ketorolac and morphine in paediatric outpatients undergoing strabismus surgery. Forty-two ASA I or II children, aged 2-12 yr, were allocated randomly to receive either ketorolac 0.75 mg kg-1 i.v. or morphine 0.1 mg kg-1 i.v. and metoclopramide 0.15 mg kg-1. Anaesthesia was induced with propofol and maintained with propofol and nitrous oxide. Pain was assessed at 15-min intervals until discharge, and the incidence of nausea and vomiting was recorded for the first 24 h. There was no difference in pain behaviour scores or recovery times. The incidence of nausea and vomiting during the first 24 h was 19% in the ketorolac group and 71% in the morphine group (P < 0.001). We concluded that ketorolac was an effective analgesic for this type of surgery and that it was associated with less postoperative emesis than morphine and metoclopramide.

Ambulatory Surgical Procedures↗

PubMed1995

Prevention of vomiting after paediatric strabismus surgery: a systematic review using the numbers-needed-to-treat method.

Randomized controlled studies were reviewed to assess the effectiveness and safety of antiemetics used for prophylaxis in paediatric strabismus surgery. Early and late vomiting (6 and 48 h after operation, respectively), and adverse effects were evaluated using the numbers-needed-to-treat method. In 27 reports with information on 2033 children, the mean incidence of early vomiting was 54% and of late vomiting 59%, without prophylaxis. Only three drugs were studied sufficiently for firm conclusions to be drawn. In the best documented regimen (droperidol 75 micrograms kg-1), four children have to be given the drug to prevent one vomiting; of the three others, one may vomit and two would not have vomited anyway; fewer than one child in 100 may have an extrapyramidal reaction and 16 may have minor adverse effects. Metoclopramide 0.15 and 0.25 mg kg-1 was significantly better than control only for early vomiting. Propofol had a high incidence of oculocardiac reflex without conferring any significant antiemetic effect: it should not be used. The benefits of prophylactic antiemetic therapy are not proven.

Antiemetics↗

PubMed1998

Laser stimulation of acupuncture point P6 reduces postoperative vomiting in children undergoing strabismus surgery.

We conducted a double-blind, randomized, placebo-controlled study to investigate the effectiveness of P6 acupuncture on postoperative vomiting in children undergoing strabismus surgery. Acupuncture was performed by laser stimulation with a low-level laser. Laser stimulation of P6 was administered 15 min before induction of anaesthesia and 15 min after arriving in the recovery room. In the laser stimulation group, the incidence of vomiting was significantly lower (25%) than that in the placebo group (85%).

Acupuncture Points↗

PubMed2001

Dexamethasone is a cost-effective alternative to ondansetron in preventing PONV after paediatric strabismus repair.

This study evaluated the antiemetic efficacy, cost-effectiveness and clinical utility of prophylactic ondansetron and dexamethasone compared with placebo in the prevention of postoperative nausea and vomiting (PONV) in 135 children (2-15 yr, ASA I-II) undergoing strabismus repair. After induction with halothane and nitrous oxide in oxygen or i.v. thiopental, the children received i.v. dexamethasone 1 mg kg(-1) to a maximum of 25 mg, ondansetron 100 microg kg(-1) to a maximum of 4 mg or placebo (n=45). Episodes of PONV were recorded for the first 24 h after the operation. True outcome measures (parental satisfaction score, duration of stay in the postanaesthesia care unit and fast tracking time), therapeutic outcome measures (number needed to prevent (NNTP) PONV) and the cost to benefit a child with each drug were analysed. The incidence and severity of PONV in the first 24 h were significantly less in the dexamethasone and ondansetron groups than in the placebo group (P<0.05). The incidence (P=0.04) and severity (P=0.03) of PONV at the 6-24 h epoch were significantly less in the dexamethasone group than in the ondansetron group. Recovery time (P=0.07), fast tracking time (P=0.6), parental satisfaction scores (P=0.08) and NNTP PONV were comparable (NNTP=2) in both the ondansetron and the dexamethasone group. The cost to benefit a child with dexamethasone was approximately 22 times less than that of ondansetron.

Adolescent↗

PubMedDate not supplied

Familial dextrocardia, divergent strabismus and situs inversus of optic disc.

A family is described in which three of four siblings have major congenital cardiac defects in association with ocular abnormalities. The eldest sibling has isolated dextrocardia and the second has total situs inversus. The fourth child has both atrial and ventricular septal defects, with pulmonary hypertension and right ventricular hypertrophy. The mother and third sibling have normal hearts but exhibit a number of ocular defects. The principal ocular anomalies demonstrated in this family are divergent strabismus, bilateral situs inversus of the optic disc, and myopia. The hereditary aspect of these multiple findings is discussed.

Child↗

PubMed1997

A randomized multicenter study of remifentanil compared with alfentanil, isoflurane, or propofol in anesthetized pediatric patients undergoing elective strabismus surgery.

Remifentanil hydrochloride is a new, ultrashort-acting opioid metabolized by nonspecific plasma and tissue esterases. We conducted this multicenter study to examine the hemodynamic response and recovery profile of premedicated children undergoing strabismus repair who were randomly assigned to receive one of four treatment drugs (remifentanil, alfentanil, isoflurane, or propofol) along with nitrous oxide and oxygen for maintenance of anesthesia. Induction of anesthesia was by nitrous oxide, oxygen, and halothane or nitrous oxide, oxygen, and propofol. Anesthesia was then maintained with remifentanil 1.0 microgram/kg over 30-60 s, followed by a constant infusion of 1.0 microgram.kg-1.min-1, alfentanil 100 micrograms/kg bolus followed by a constant infusion of 2.5 micrograms.kg-1.min-1, propofol 2.5 mg/kg bolus followed by a constant infusion of 200 micrograms.kg-1.min-1, or isoflurane 1.0 minimum alveolar anesthetic concentration. The infusions of the anesthetics and the administration of the inhaled gases were adjusted clinically by predetermined protocols. Elapsed time intervals from the end of surgery to the time the patients were tracheally extubated and displayed purposeful movement, as well as the time the patients met the postanesthesia care unit (PACU) and hospital discharge times, were recorded. Heart rate and systolic and diastolic blood pressure were measured at fixed intervals. In addition, cardiovascular side effects (bradycardia, hypotension, and hypertension) as well as vomiting, pruritus, agitation, and postoperative hypoxemia were also noted. There were no significant differences in patient demographics among the treatment groups. There was no difference in the early recovery variables (times to extubation and purposeful movement) or the times to PACU and hospital discharge among groups. There were significant differences in side effects among the groups. Patients who received remifentanil had higher PACU objective pain-discomfort scores than those who received alfentanil and propofol. Patients anesthetized with alfentanil had a greater incidence in the use of naloxone and a greater incidence of postoperative hypoxemia compared with those anesthetized with remifentanil. The incidence of postoperative hypoxemia was the same for remifentanil, propofol, and isoflurane groups. There were no significant differences in the incidence of emesis among the four groups, and all four groups had similar hemodynamic profiles. We conclude that remifentanil appears to be an effective drug for anesthesia. Its hemodynamic and recovery profile appear similar to other comparable drugs. Based on previous pharmacokinetic studies, the 1.0 microgram.kg-1.min-1 infusion may be twice the 50% effective dose observed in adults. In this study, the relative "overdose" of remifentanil was well tolerated and did not prolong recovery.

Alfentanil↗

PubMed1989

Incidence of emesis and postanesthetic recovery after strabismus surgery in children: a comparison of droperidol and lidocaine.

The authors sought to compare the antiemetic and sedative postanesthetic effects of droperidol versus lidocaine given intravenously. One hundred and fifty children, ASA physical status I or II, ages 2-15 yr, were studied. Each child was randomly assigned to receive either droperidol, 0.075 mg/kg; lidocaine, 1.5 mg/kg; or a combination of lidocaine, 1.5 mg/kg, and a reduced dose of droperidol, 0.025 mg/kg, immediately after induction of anesthesia, which was with thiopental, atropine, and succinylcholine. Anesthesia was maintained with halothane and nitrous oxide. The incidence of postanesthetic vomiting was 22% in the droperidol-alone group, which was significantly less than the lidocaine-alone group (50%). The incidence of vomiting in the combination group (30%) was not significantly different from either the droperidol- or lidocaine-alone groups. The time in the recovery room was significantly shorter for patients given lidocaine alone than those given droperidol alone or the combination. However, the mean time intervals from completion of surgery to recovery of full alertness and to discharge from the hospital did not differ significantly among the three groups. In summary, the authors found that intravenous droperidol is significantly more effective than lidocaine in reducing the incidence of vomiting in unpremedicated children after strabismus surgery. Furthermore, droperidol did not delay either the time to recovery of full alertness or the time to discharge from hospital compared to lidocaine.

Adolescent↗

PubMed1990

Metoclopramide reduces the incidence of vomiting following strabismus surgery in children.

This randomized, double-blind study evaluated the efficacy of metoclopramide administered at the completion of surgery as an antiemetic agent in pediatric patients undergoing ambulatory strabismus surgery; 126 unpremedicated ASA Physical Status 1 and 2 children ranging in age from 2 to 18 yr served as subjects. All received general anesthesia with halothane, N2O, and O2; tracheal intubation was facilitated with intravenous (iv) atracurium 0.5 mg/kg. Intravenous atropine 0.02 mg/kg and lactated Ringer's solution with 5% dextrose equivalent to 4 h of maintenance fluids were administered during surgery. Neither opioids nor droperidol were given intraoperatively. At the completion of surgery, residual muscle paralysis was reversed with atropine 0.02 mg/kg (maximum dose 1.0 mg) and neostigmine 0.07 mg/kg (maximum dose 5.0 mg), and the stomach was decompressed prior to tracheal extubation. After the patient had been transferred to the postanesthesia recovery room (PARR) either metoclopramide 0.15 mg/kg or normal saline was administered intravenously to the children over a 1-min period. A research associate monitored the children for the incidence of post-operative vomiting and the time required for each child to meet discharge criteria from Short Stay Recovery Unit (SSRU). If a child vomited more than three times in both the PARR and SSRU, the vomiting was construed to be severe and the patient was offered further antiemetic treatment with iv droperidol 70 micrograms/kg. The incidence of postoperative vomiting in the metoclopramide group was 37% versus 59% in the placebo group (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1985

Quantitative evaluation of the strabismus patient.

Quantitative techniques of measuring ocular motor function have proven extremely useful in evaluating the strabismus patient. The forced duction test has been valuable in determining the extent of mechanical restrictions and, in some instances, indirectly provides information about muscle strength. The active force generation test is a direct measure of active muscle force, while the differential intraocular pressure test (which may be easier to perform) provides data on active force indirectly. Saccadic velocity studies reveal the presence of muscle paresis or paralysis as contrasted with restrictions. Several neuro-ophthalmic conditions have typical eye movement patterns that are helpful in identifying them correctly. Saccadic velocity tests can also be helpful in diagnosing a disinserted extraocular muscle. Quantitative studies assist in more accurate diagnosis and are helpful in therapeutic decision making in terms of the timing and type of therapy indicated.

Animals↗

PubMed1976

Strabismus measurements in the Siamese cat.

Anatomical and neurophysiological studies suggest a relationship between "abnormal" visual pathways and strabismus found in the Siamese cat. A telephotographic method for measuring eye positions in these cats reveals that newborn Siamese cats have a conspicuous exotropia appearance. Adult animals appear to have esotropia, orthophoria, or exotropia, which can be intermittent.

Age Factors↗