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Query: UMLS:C0038379 (strabismus)
 9,317 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Anterior segment ischemia changes can occur without detachment of any muscles. The most common cause of such ischemic changes of the anterior segment is the removal of too many rectus muscles in one operation. Twenty dog eyes and eight monkey eyes were subjected to the disinsertion and detachment of various combinations of extraocular muscles. They were sacrificed at intervals from 30 to 90 days. During the observation period, they were observed for gross and slit lamp changes. The enucleated eyes were studied microscopically for signs of ischemic and necrotic changes. Two patients who were studied, observed, and treated for anterior segment ischemia following muscle surgery are described. The changes which occur after muscle surgery are extensive and include corneal edema, cataract, chemosis, corneal changes, decreases in intraocular pressure, decreases in outflow or glaucoma and frank necrosis. The variables which lead to this reaction is described in detail. Also, some unanswered queries, such as the duration of the reaction and the time interval of the reaction after multiple muscle surgeries, are discussed.
J Pediatr Ophthalmol Strabismus
PMID:Production of anterior segment ischemia. 10 21

Iris circulation was investigated by fluorescein iris angiography in 33 human eyes before and after tenotomy of one or more recti for correction of strabismus. Tenotomy of one or both horizontal recti produced no appreciable circulatory disturbance in the iris, but tenotomy of superior or inferior rectus produced circulatory delay in superior temporal or inferior temporal sectors, respectively, of the iris. When tenotomies of a horizontal and one or two vertical recti were combined, the defect occurred in the region of the vertical rectus only. Blood supply of the nasal half of the iris was usually not disturbed by tenotomy of the vertical and/or medial rectus. The findings indicate that the blood supply of the iris is segmental and suggest that, in strabismus surgery, cutting the two vertical recti along with the lateral rectus may subject the eye to the risk of anterior segment ischemia. In the light of the present findings, physiological anatomy of the blood supply of the iris and role of the major arterial circle of the iris are discussed.
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PMID:Fluorescein iris angiography. II. Disturbances in iris circulation following strabismus operation on the various recti. 67 78

A 69-year-old woman with chronic lymphocytic leukemia developed segmental iris atrophy and iridocyclitis after routine surgery for exotropia. Both the clinical picture and fluorescein angiogram indicated anterior segment ischemia. It is postulated that this was related to hyperviscosity of the blood caused by a high white blood cell count (114,000/cu mm). The possibility of anterior segment ischemia should be kept in mind when contemplating strabismus or retinal detachment surgery in the presence of hematologic disorders likely to increase blood viscosity. In these cases a minimal amount of surgery should be done with proper supportive therapy. Strabismus surgery should be done in stages allowing for hemodynamic compensation between procedures.
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PMID:Anterior segment ischemia and sector iris atrophy: after strabismus surgery in a patient with chronic lymphocytic leukemia. 103 46

Preservation of anterior ciliary vessels (ACVs) during strabismus surgery using microscopic dissection techniques and the operating microscope has been previously described. We describe a technique using standard loupe magnification for vessel preservation, in 77 patients, ages 7 months to 69 years, who had surgery between January 1989 and September 1990. ACVs, with a small sheath of connective tissue, were dissected off the surface of the muscles and tendons using blunt and sharp dissection with Knapp iris hooks and Vannas scissors. Key elements of the dissection were sufficient separation of the vessel complex from the anterior tendon insertion and the use of blunt rather than sharp dissection. We successfully preserved 125 ACVs in 97 muscles. Ninety-five vessels were saved with 71 recessions, 14 with 13 resections, and 16 with adjustable sutures. The success rate of surgery was 85% in surgeries done either with or without anterior ciliary preservation. Vessel dissection time averaged 5 to 10 minutes per muscle. ACV preservation can be easily and successfully performed in routine strabismus cases. The procedure does not require the operating microscope and can be done under standard loupe (1.5 to 3.0 x) magnification. This procedure theoretically reduces the risk of anterior segment ischemia in situations where the patient is thought to be at significant risk for this complication.
J Pediatr Ophthalmol Strabismus
PMID:Preservation of anterior ciliary vessels during strabismus surgery: a nonmicroscopic technique. 158 78

Strabismus surgery results in the permanent interruption of anterior ciliary blood flow, predisposing the eye to anterior segment ischemia (ASI). A primate model was used to assess the effectiveness of a new muscle-scleral tuck for preserving anterior ciliary artery circulation. The model consisted of removing 3 rectus muscles from both eyes of 2 rhesus monkeys, then performing a tuck on the inferior rectus (IR) right eye while leaving the left IR as a control. Four weeks later, a modified tuck was performed on the virgin left IR. Fluorescein iris angiograms of both eyes were obtained, and preoperative angiograms at 5-15 sec. showed normal 360 degrees perfusion. Postoperative follow-up angiograms showed segmental superior temporal filling defects and preservation of perfusion in the distribution of the IR. Comparison of fellow eyes tucked vs control IR showed no difference in the filling pattern in both monkeys. Comparison of the same eye before and after tuck also showed essentially the same filling pattern in all 4 eyes with preservation of inferior circulation. Our conclusion is that the modified tuck preserves the anterior ciliary blood flow and may be useful as a muscle-strengthening procedure in patients predisposed to developing ASI.
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PMID:Effect of a modified rectus tuck on anterior ciliary artery perfusion. 194 98

Removal of a rectus muscle results in permanent interruption of blood flow in the corresponding anterior ciliary artery, predisposing to anterior segment ischemia (ASI). A subhuman primate model of ASI was developed in order to study a novel muscle tuck procedure designed to preserve anterior ciliary artery circulation. Fluorescein angiograms were obtained before and after surgery to determine the effect of the muscle surgery on iris circulation. A total of 12 eyes from 12 cynomolgus monkeys underwent strabismus surgery consisting of tenectomy of all 4 rectus muscles in 3 eyes, tenectomy of 3 rectus muscles in 3 eyes, and tenectomy of 3 rectus muscles and muscle to sclera tuck of the remaining recti in 6 eyes. Postoperative angiograms documented preservation of perfusion in the distribution of the tucked muscle in all cases except one, in which there was iatrogenic trauma and disruption of anterior ciliary arteries. The modified tuck procedure thus appears to preserve anterior ciliary artery blood flow, and may be useful as a muscle strengthening procedure in patients predisposed to developing ASI.
J Pediatr Ophthalmol Strabismus
PMID:Effect of a modified rectus tuck on anterior segment circulation in monkeys. 205 Dec 93

Fornix conjunctival incisions in strabismus surgery may provide partial protection against anterior segment ischemia by preserving the perilimbal conjunctival-Tenon's circulation, which is disrupted with limbal conjunctival incisions. Six adult cynomolgus monkeys underwent tenotomies of three or four rectus muscles by making limbal conjunctival incisions in one eye and fornix incisions in the other. Iris fluorescein angiography and slit-lamp biomicroscopy were used to monitor changes. The eyes that had limbal incisions exhibited more severe anterior segment ischemic changes than the eyes that had fornix incisions in every instance of four rectus muscle surgery.
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PMID:A primate model of anterior segment ischemia after strabismus surgery. The role of the conjunctival circulation. 232 23

Microdissection of the muscular vessels allows recessions, resections, or transpositions of the recti muscles without interrupting the blood flow to the corresponding anterior ciliary arteries. This avoids postoperative impaired blood flow to the anterior segment and may play a role in preventing anterior segment ischemia syndrome. The use of a fine-hooked cannula and microscissors, in addition to the usual strabismus surgery instruments, is described.
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PMID:Vascular microdissection in strabismus surgery. 236 41

Conventional, full-tendon, rectus muscle surgery disrupts the anterior ciliary vessels. This may lead to anterior segment ischemia when the number of interrupted vessels is sufficient to significantly compromise anterior segment blood flow. Clinical observations and histologic studies provide new anatomic information concerning the course of the anterior ciliary vessels in the sub-Tenon's region. These studies demonstrate the feasibility of dissection and preservation of the anterior ciliary vessels during rectus muscle surgery. Dissection and preservation of 35 clinically apparent anterior ciliary vessel groups were attempted on 15 rectus muscles during strabismus surgery. The unplanned vessel destruction rate was 9.5%. Procedures included 12 recessions, 1 resection, and 2 full-tendon transpositions. The possible role of this procedure in the prevention of anterior segment ischemia is discussed.
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PMID:Preservation of the anterior ciliary vessels during extraocular muscle surgery. 272 79

Necrotizing scleritis with inflammation of the right eye developed after bilateral eye muscle surgery for thyroid ophthalmopathy. Debilitating pain, delay in onset, and involvement of the sclera distinguish this condition from anterior segment ischemia. The surgery may have acted as a nonspecific trigger in an eye at risk for scleritis. Necrotizing scleritis has occurred infrequently after other types of eye surgery but, to our knowledge, has not been previously reported as a complication of eye muscle surgery.
J Pediatr Ophthalmol Strabismus
PMID:Necrotizing scleritis following strabismus surgery for thyroid ophthalmopathy. 279 12


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