Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Strabismus”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,099 records · Page 61Linked to original sources
PubMedDate not supplied

Optimum timing of postoperative adjustment in a rabbit model of adjustable suture strabismus surgery.

Strabismus surgeons disagree on the optimum timing of the postoperative adjustment in adjustable suture surgery. We compared the peak force necessary for adjustment at various postoperative times using a rabbit model. Twenty-four eyes of 12 rabbits underwent a superior rectus recession of 5 mm using a standard adjustable suture technique. The eyes were randomized to adjustment at 15 minutes, and at 6, 24, and 48 hours postoperatively. The peak force required to advance the muscle 3 mm was measured using a strain gauge. During each adjustment, the peak force was noted to be that required for initial disinsertion of muscle from sclera. The mean peak force required was 14 +/- 5 g at 15 minutes, 37 +/- 10 g at 6 hours, 60 +/- 40 g at 24 hours, and 103 +/- 52 g at 48 hours. There was a significant relationship between the time of adjustment and the peak force required for adjustment (F = 7.8, P = 0.001). Post-hoc analysis showed that the peak force required at 48 hours was greater than that required at 24 hours (P = 0.04), 6 hours (P = 0.003), and at 15 minutes (P = 0.0002). The force required for adjustment at 24 hours and beyond was greater than the maximal force generated by an extraocular muscle. We therefore suggest that the postoperative adjustment should be performed within the first 24 hours.

Animals↗
PubMed1994

[Treatment of strabismus with botulinum toxin].

Having used botulinum toxin for four years, we describe our experience in one hundred squinting patients and compare our results with the literature. We have good results in unilateral sixth nerve palsy and small deviations with binocular potential. Botulinum toxin can also be helpful in third and fourth nerve palsy, in Graves' ophthalmopathy, as an adjunct to transposition surgery and in cases of under- or overcorrections after surgery. In cases of muscle fibrosis and wide angle strabismus, the results are more disappointing. We describe an original method of conditioning the toxin in individual doses which eases the botulinum consultation processing.

Botulinum Toxins↗
PubMed1994

[Comparative study of propofol versus thiopental-halothane in the occurrence of oculocardiac reflex and postoperative vomiting after surgery for strabismus in children].

Strabismus surgery in children is associated with side-effects, intraoperative oculocardiac reflexes in relation with muscular tractions and postoperative vomiting. Studies with propofol anaesthesia in this surgery have shown a lower incidence of these side-effects. So, a prospective study compared these incidences with propofol (P) versus thiopental/halothane (T+H) anaesthesia. Propofol appears to be efficient in reducing postoperative vomiting but might be associated with more frequent OCR.

Adolescent↗
PubMedDate not supplied

[Squint angle, eyeball length and surgical results in horizontal strabismus].

The studies comprised 70 patients with convergent and divergent strabismus. Deviation of the eye was measured before and after surgery with commonly applied methods. The anterior-posterior axial length of the eyeball was determined with A-scan and B-scan USG. Typical surgical methods, recession and reaction of the horizontal muscles were performed in one- (79.8%) or two-stage (20.2%) operations. The patients were divided in 5 groups depending on the range of the operation. Coefficient of correlation (r) between the deviation and length of the eyeball after surgery was determined for each group. Its values were highest in esotropia; 0.87 when the recession/resection ratio was 3.5/7 mm and 0.82 when it was 3.5/6. In exotropia, the coefficient was low but this group was not numerous enough for statistics. The results of surgery correlated more strongly with the length of the eyeball than with the degree of deviation. The authors concluded that the axial length of the eyeball should be taken in calculation of the operation range.

Adolescent↗
PubMed1994

Ocular dominance column development: strabismus changes the spacing of adjacent columns in cat visual cortex.

To investigate the role of visual experience for the gross layout of ocular dominance (OD) columns in the visual cortex, I compared the respective patterns in normally raised and strabismic cats. OD domains were visualized by (1) transneuronal labeling of the afferents from the left or right eye with intraocular 3H-proline injections or (2) 14C-2-deoxyglucose autoradiography after monocular visual stimulation in awake animals. To obtain the complete pattern of OD columns, flat-mount sections were prepared from the unfolded cortical hemispheres. Eliminating correlated activity between the two eyes by making the animals strabismic influenced the gross layout of the OD domains. In area 17, OD domains become more sharply delineated than in normal animals and spaced more widely. Spatial frequency analyses revealed a mean spacing of adjacent columns of 1100-1300 microns in strabismic and of 800-1000 microns in normal cats. In area 18, the spacing of the ocular dominance domains is larger than in area 17 for both normal and strabismic cats (1500-1650 microns), but little influenced by strabismus. These results indicate that in area 17 decreased correlation of activity between the eyes alters the periodicity of OD columns. In addition, these observations suggest that not only the segregation of afferents into distinct columns but also the final expression of the columnar grid is influenced by visual experience, and in particular by the temporal patterning of neural activity. This is further evidence for the hypothesis that the development of OD columns is governed by activity-dependent self-organizing principles.

Animals↗
PubMed1975

Histology of the monkey lateral geniculate nucleus after unilateral lid closure and experimental strabismus: further observations.

The histology of binocularly and monocularly innervated portions of the lateral geniculate nucleus (LGN) was studied after unilateral lid closure and experimental esotropia and exotropia in the Macaca mulatta and the results were compared with behavioral and neurophysiological data. The most severe cell shrinkage occurred in two animals who had one eye sutured during the first week of life; all dorsal and ventral deprived LGN layers, including the monocular segment, were involved. Less severe anomalies and sparing of the monocular segment were encountered in esotropic amblyopic monkeys and the least severe changes were in exotropic animals without amblyopia. The severity of behavioral, neurophysiologic, and histologic changes following unilateral lid suture or experimental strabismus could be correlated in all animals studied. The data indicate that the order of susceptibility of the LGN to reduced or abnormal visual input early in life appears to be: dorsal laminae greater than ventral laminae greater than monocular segment.

Amblyopia↗
PubMed1993

Necrotizing scleritis and transient myopia following strabismus surgery.

Necrotizing scleritis may occur following ocular surgery, most commonly after cataract extraction. This complication developed in a 60-year-old woman following strabismus surgery for a gaze palsy and sixth-nerve paresis following a stroke. Although an autoimmune process is present in many patients with necrotizing scleritis, none was detected in this patient. Inflammation was controlled with topical and systemic corticosteroids and ibuprofen. Good visual acuity was preserved, and improved ocular alignment was achieved. Transient myopia, not previously reported in necrotizing scleritis, was observed.

Female↗
PubMed1993

Saccadic underaction in concomitant strabismus and Hering's law: a new neurophysiologic model for binocular motor correspondence.

Hering's law of equal innervation has remained so far as an universal truth with no scientific basis. However, recent reports of Saccadic underactions in concomitant strabismus indicating asymmetric ocular motor innervation is in contradiction to the law. In an effort to understand the inequalities of binocular movements, we propose a neurophysiologic model for both normal and abnormal eye movements. The model hypothesizes that any binocular movement results from the yoking of two monocular reflex loops corresponding to the two eyes, during the plastic stage of development of ocular motor reflexes. The retinal target discrepancy triggers the reflex loop resulting in a monocular corrective movement. As there is a common binocular field, the stimuli to the two eyes are similar causing a similar binocular corrective movement. In abnormal cases coupling of asymmetric motor loops may occur resulting in alternate or unilateral saccadic underactions.

Electrooculography↗
PubMedDate not supplied

[The importance of using the computer in treating children with strabismus and amblyopia].

A method for therapy of strabismus and amblyopia with the use of IBM PC AT type computer is suggested. It consists in active interaction of a patient with various test objects on the monitor and is realized via a special set of programs. Clinical indications for the use of a new method are defined. Its use yielded good results in 82 of 97 children.

Adolescent↗
PubMed1993

Use of a silicone sheet for delayed adjustable strabismus surgery.

Adjustable strabismus surgery sometimes fails because of changes in the angle of deviation developing a few days after surgery. A thin silicone sheet placed between the muscle and sclera prevents postoperative adhesions between these tissues, allowing adjustment to be delayed for up to 11 days after surgery. Once the final adjustment is made, the silicone sheet is removed.

Humans↗
PubMed1993

Occlusion therapy of Japanese children with anisometropic amblyopia without strabismus.

We examined 38 children (20 boys and 18 girls) with anisometropic amblyopia without strabismus who had been treated with occlusion therapy. At the initial visit, their ages ranged from five to ten years. Their visual acuity scores improved after therapy, and this was unrelated to patient age. The amount of anisometropia, visual acuity at the initial visit, and compliance were related to improved visual acuity in the amblyopic eye. The visual acuity improved for six months after therapy. No further gains were detected thereafter.

Amblyopia↗
PubMedDate not supplied

[Surgery of concomitant strabismus with an adjustable suture].

The authors emphasize the main features of the "adjustable suture" in concomitant strabismus surgery. Good results (over 92% of orthotropia) were noted especially in very young children (under 3 years of age)--cases in which an exact study on the status of motricity and vision is not possible.

Adolescent↗
PubMedDate not supplied

[The incidence of refractive errors in strabismus with an early onset].

The paper represents one study effected at a number of two hundred and fifty children under three years old, examinated in Ophthalmological Clinic between 1992 and 1995. It was examinated strabismic deviation, visual acuity, state of binocular-eyesight refraction. Most of children (59%) present to hypermetropia under three dioptry; 23.3% medium hypermetropia (3-6 dioptries). Little percentage under 10% present others refraction vices: big hypermetropia, astigmatism, anisometropia, myopia. After optic correction and occlusion, most of deviations remained unaltered requiring surgical subsequent correction. This fact certifys the preponderence of neurogenic pathogenesis and not adjustment in strabismus with precocious debut.

Age Distribution↗
PubMed1996

Sodium hyaluronate as a tool in strabismus surgery in rabbits.

BACKGROUND AND OBJECTIVE: The authors tested whether coating tissue with sodium hyaluronate (Na-HA) reduced postoperative adhesions and accelerated the healing process in strabismus surgery. MATERIALS AND METHODS: The surgical technique was tested during recession and resection operations performed on 30 rabbits and was compared with the use of NaCl 0.9%. Clinical, biomicroscopic examinations were performed on postoperative days 1, 2, 7, and 30 and histopathologic examinations were performed on postoperative days 2, 7, and 30. RESULTS: Clinically, there were no statistically significant differences between the study group and the control group. Also, there were no statistically significant differences between the two groups for most of the histopathologic criteria; however, new vessel formation was smaller with Na-HA than without it. Statistical significance was defined as P < .05. CONCLUSION: The authors found no significant positive effect of Na-HA on postoperative healing in rabbits.

Animals↗
PubMed1996

Postoperative nausea and vomiting after strabismus surgery: mechanisms, treatment, and implications for practice.

The occurrence of postoperative nausea and vomiting in children after strabismus surgery has historically been a challenging aspect of anesthetic management. This article provides an overview of the cause, physiology, and mechanisms of post surgical vomiting in this patient population. Current pharmacological treatment modalities and implications for future practice are examined.

Child↗
PubMed1996

Conjunctival closure in strabismus surgery: Vicryl versus fibrin glue.

Six patients undergoing bilateral symmetric strabismus surgery were enrolled in this study. For each subject, incisions were closed with Vicryl in one eye and glue in the other. The conjunctival closure with the Vicryl suture resulted in increased discomfort and inflammation during the early postoperative period compared with fibrin glue. However, the difference between the Vicryl and the glue disappeared after 14 days.

Conjunctiva↗
PubMed1996

[Amblyopia, refractive errors and strabismus in congenital ptosis].

The incidence of amblyopia in the normal population is 2-6%, whereas among patients with congenital ptosis it can be as high as 50%. We reviewed 146 cases of congenital ptosis in patients aged between 5 months and 15 years and compared them to a control group of 34 age- and sex-matched patients. In 78 children (156 eyes) reliable optotype visual acuity could be obtained. Fifty-three eyes (34%) were amblyopic. Ametropia was responsible for 34% and anisometropia for 28.3% of the amblyopia cases. In 25.4% of cases strabismus, and in 11.34% stimulus deprivation, was the reason for the development of amblyopia. Children with congenital ptosis should have retinoscopy done in cycloplegia, and refractive errors should be corrected early. Controlled patching therapy should also be started early. Since stimulus deprivation amblyopia is rare, congenital ptosis need not be corrected early in life.

Amblyopia↗
PubMed1996

Intermittent diplopia and strabismus caused by ocular neuromyotonia.

PURPOSE: Two cases illustrate the symptoms, signs, etiologies, and treatment of ocular neuromyotonia (ONM). METHODS: The histories, neuroradiologic tests, and/or biopsy revealed the etiologies of ONM in both patients. Clinical observations, videotaping, and electronic eye movement recordings documented the eye movements. RESULTS: A 72-year-old man with chronic arachnoiditis following myelography with thorium dioxide (Thorotrast) developed intermittent diplopia and a partial right third nerve palsy. Left gaze induced spasm of the right medial rectus. Right gaze produced right lateral rectus spasm. A 66-year-old woman, who had radiation treatment for a pituitary tumor and acromegaly, had intermittent spasm of the left medial rectus muscle and left esotropia. The episodes occurred spontaneously and were induced by right gaze. A left internuclear ophthalmoplegia was also found. Carbamazepine (Tegretol) abolished the ONM in both patients. CONCLUSIONS: Although ONM is an unusual cause of intermittent diplopia and strabismus, its distinctive clinical features identify it. Injury to the peripheral cranial nerves probably leads to segmental demyelination, axonal hyperexcitability, and a self-perpetuating, reverberating circuit, which causes spasms of the extraocular muscles.

Aged↗