Vertical deviation and A pattern of type III Duane retraction syndrome.

BACKGROUND: Researches in ocular electromyography (EMG) and Magnetic resonance imaging (MRI) of patients with Duane retraction syndrome (DRS) suggest that there may be additional abnormalities such as paradoxical innervation between horizontal rectus muscles and vertical rectus muscles, hypoplasia of vertical rectus muscle and that oblique muscles may also contribute to the heterogeneity of the clinical manifestation of DRS. This paper reports the results of superior rectus recession for vertical deviation and A pattern in DRS Type III and discusses the pathogenesis of the disease. METHODS: Superior and lateral rectus recession were performed in 5 cases of Huber type III DRS to treat vertical deviation and A pattern strabismus. Before operation, MRI of the brain, brainstem, cavernous sinus, and orbits were performed. RESULTS: All subjects had unilateral limitation of both abduction and adduction, with palpebral fissure narrowing and globe retraction in adduction. Three cases had A pattern of strabismus, three cases had hypertropia. The abducens nerves (CN6) were either absent or hypoplasitic in the brainstem in all patients. Two eyes had larger oculomotor foramen. Two eyes had hypoplasia of the superior rectus and the inferior rectus. There was presumably a branch of the third cranial nerve (CN3) innervating the lateral rectus (LR) in one eye. While in another eye, two branches of CN3 sent into medial rectus were revealed. After surgery, vertical deviation in the primary position was reduced in all patients and A pattern was eliminated in 3 patients. One patient developed 10Δ consecutive esotropia postoperatively. CONCLUSION: The results suggest that structural abnormalities of vertical muscle and abnormal orbital innervation may be related to vertical deviation and the presence of A pattern in DRS type III. Recession of the superior rectus muscle seems to be a safe and effective treatment for vertical deviation and A pattern strabismus in DRS Type III.

Gene transfer of kringle 5 of plasminogen by electroporation inhibits corneal neovascularization.

PURPOSE: To test the efficacy of naked plasmid that expresses human kringle 5 of plasminogen (K5) in suppressing experimental corneal neovascularization in a rat model. METHODS: A eukaryotic expression plasmid encoding human K5 (pSecK5) was constructed. COS cells were transiently transfected with pSecK5 using a lipid-based transfection reagent. K5 secretion was confirmed by Western blot analysis. The effect of the secreted K5 on the proliferation of human umbilical vein endothelial cells (HUVECs) was investigated colorimetrically. Forty-three Sprague-Dawley rats were used for a corneal neovascularization suppression experiment. Corneal injury was induced by placing a disk of filter paper (immersed in 1 mol/l NaOH, 3.0 mm in diameter) on the corneal surface for 2 min. The cornea was immediately washed with saline. pSecK5 and empty plasmids were injected subconjunctivally, and square-wave electric pulses were immediately applied to the eyes. The expression of K5 was analyzed by reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry. The extent of corneal neovascularization was evaluated by scores. RESULTS: The constructed plasmid could express itself in COS cells. Conditioned medium from K5-transfected COS cells apparently inhibited HUVEC proliferation, compared with conditioned medium from COS cells transfected with empty plasmid or nontransfected cells. RT-PCR and immunohistochemistry confirmed the expression of K5 in the conjunctiva and cornea. Corneal neovascularization was significantly suppressed by K5 gene transfer in rats' eyes. CONCLUSION: In a rat model, K5 gene transfer by subconjunctival injection and electroporation can effectively inhibit corneal neovascularization induced by an alkali burn.