PURPOSE: To evaluate the result of re-operation on the deviated eye of recurred, consecutive or undercorrected sensory strabismus after surgery. METHODS: The medical records of 11 patients who had received second strabismus operation on the deviated eye due to recurred, consecutive or undercorrected sensory strabismus were studied retrospectively. RESULTS: Among the 11 patients, five patients were operated for recurred exotropia after surgery of sensory exotropia (group 1), two for consecutive exotropia after surgery of sensory esotropia (group 2), and four for undercorrected esotropia after surgery of sensory esotropia (group 3). Re-operation was performed 19.2+/-12.6 years after the first operation and the mean preoperative deviation before re-operation was 30.0+/-8.66 prism diopters (PD), 32.5+/-10.6PD, and 32.5+/-8.66PD, respectively. In all cases, a small amount of recession or resection compared with the usual surgical dosage was applied in re-operation on the deviated eye. The mean follow-up period after re-operation was 12.3+/-14.2 (1-48 months). Among the 11 patients, postoperative deviations less than 10PD were achieved postoperatively in 8 (72.7%) at 1 month and of the 8 patients with follow-up data beyond 6 months, 5 (62.5%) showed orthotropia within 10PD at 6 months or later. CONCLUSIONS: The surgical result of re-operation on the deviated eye of recurred, consecutive or undercorrected sensory strabismus after the first surgery was satisfactory in spite of the reduced amount of surgical correction compared with the surgical dosage recommended for the non-operated eye.
Adolescent ; Adult ; Child ; Child, Preschool ; Female ; Humans ; Male ; Oculomotor Muscles/*surgery ; Ophthalmologic Surgical Procedures ; Recurrence ; Reoperation ; Strabismus/*surgery ; Time Factors ; Treatment Outcome

PURPOSE: To evaluate the result of re-operation on the deviated eye of recurred, consecutive or undercorrected sensory strabismus after surgery. METHODS: The medical records of 11 patients who had received second strabismus operation on the deviated eye due to recurred, consecutive or undercorrected sensory strabismus were studied retrospectively. RESULTS: Among the 11 patients, five patients were operated for recurred exotropia after surgery of sensory exotropia (group 1), two for consecutive exotropia after surgery of sensory esotropia (group 2), and four for undercorrected esotropia after surgery of sensory esotropia (group 3). Re-operation was performed 19.2+/-12.6 years after the first operation and the mean preoperative deviation before re-operation was 30.0+/-8.66 prism diopters (PD), 32.5+/-10.6PD, and 32.5+/-8.66PD, respectively. In all cases, a small amount of recession or resection compared with the usual surgical dosage was applied in re-operation on the deviated eye. The mean follow-up period after re-operation was 12.3+/-14.2 (1-48 months). Among the 11 patients, postoperative deviations less than 10PD were achieved postoperatively in 8 (72.7%) at 1 month and of the 8 patients with follow-up data beyond 6 months, 5 (62.5%) showed orthotropia within 10PD at 6 months or later. CONCLUSIONS: The surgical result of re-operation on the deviated eye of recurred, consecutive or undercorrected sensory strabismus after the first surgery was satisfactory in spite of the reduced amount of surgical correction compared with the surgical dosage recommended for the non-operated eye.
Adolescent ; Adult ; Child ; Child, Preschool ; Female ; Humans ; Male ; Oculomotor Muscles/*surgery ; Ophthalmologic Surgical Procedures ; Recurrence ; Reoperation ; Strabismus/*surgery ; Time Factors ; Treatment Outcome

PURPOSE: To report the clinical experience and surgical results of modified transposition surgery, in which half-width tendons are isolated and sutured into the paralyzed extraocular muscle. METHODS: We retrospectively reviewed the medical records of 6 patients (7 eyes), who had undergone modified transposition surgery to correct severe limitation of eye movement from January 1996 to December 2001. First, we divided the half-width tendons of two rectus muscles adjacent to the paralyzed rectus muscle and disinserted the halves from the sclera. The two half-width tendons were positioned underneath of the scleral insertion of the paralyzed muscle, sutured together and then sutured to the paralyzed muscle. In the case of contracture of the antagonizing extraocular muscle, recession of the antagonist was performed. RESULTS: Five of the six patients showed deviation under 15 prism diopters at primary gaze at distance, while synergistic divergence recurred in the sixth patient. CONCLUSIONS: Modified transposition surgery as described in this paper is thought to be an effective and safe method for correction of paralytic strabismus.
Contracture ; Eye Movements ; Humans ; Medical Records ; Muscles ; Retrospective Studies ; Sclera ; Strabismus ; Tendons

BACKGROUND: The purpose of this study was to investigate the differences of cerebral glucose metabolism between narcoleptic patients and normal controls. METHODS: We enrolled 24 patients with narcolepsy who underwent night polysomnography and multiple sleep latency tests to confirm the narcolepsy. 18F-fluorodeoxy glucose positron emission tomography scan was performed in all narcoleptic patients and 24 normal age-sex matched controls. To compare the cerebral glucose metabolism between the two groups, statistical parametric mapping (SPM99) was used. RESULTS: Patients with narcolepsy showed significant decreases of cerebral glucose metabolism in the bilateral rectal and subcallosal gyri, right superior frontal gyrus, right medial frontal gyrus, bilateral precuneus, right inferior parietal lobule, and left supramarginal gyrus of the parietal lobe at the uncorrected P<0.001. The bilateral posterior hypothalami and mediodorsal thalamic nuclei showed glucose hypometabolism at the level of corrected P<0.05 with small volume correction. CONCLUSIONS: This study showed cerebral glucose hypometabolism of hypothalamus-thalamus-orbitofrontal pathways in narcoleptic brains. The distribution of abnormal glucose metabolism is concordant to the cerebral pathways of the hypocretin system.
Brain ; Glucose* ; Humans ; Hypothalamus ; Metabolism* ; Narcolepsy* ; Parietal Lobe ; Polysomnography ; Positron-Emission Tomography ; Rabeprazole ; Thalamic Nuclei ; Thalamus ; Orexins

PURPOSE: Temporary deafferentation (TD) by local anesthesia in small parts of the body induces an immediate and reVersible reorganization of the receptive field (RF). It is thought that an adaptation for deafferentation would occur in the visual system. Therefore, in this study, simultaneous multi-single unit recording (SMSUR) from visual cortex (VI cortex) of rats have been carried out to characterize; 1) the TD-induced changes in the populational activities of single neurons, 2) the alteration of the neural network among neurons in each area during TD and 3) the synaptic mechanism underlying the neuronal plasticity of the visual system. METHODS: Using four channels of a multi-electrode made from tungsten microwire, the neuronal activities (evoked responses and spontaneous activities) and networks in the VI cortex of anesthetized rats have been investigated. In this study, TD was induced by a retrobulbar injection of lidocaine (2%, 0.1 ml). RESULTS: After the induction of TD, the cortical neurons showed reversed changes in their evoked reoponses. The induction of TD suppressed the activities of the target cells in the VI cortex. However, TD also caused facilitation of the activities of the neighboring neurons. The spontaneous activities of the neighboring neurons were also gradually facilitated after the induction of TD and then gradually recovered to their initial control period values. CONCLUSIONS: The results from the present study suggest that; 1) TD-induced plasticity of the central visual system involving the VI cortex may be due to disinhibition of the lateral inhibition and 2) the spontaneous activities of the VI cortical neurons, as well as evoking responses, may be involved in the TD-induced visual plasticity of anesthetized rats.
Anesthesia, Local ; Animals ; Electrophysiology ; Lidocaine ; Neuronal Plasticity ; Neurons ; Plastics ; Rats* ; Tungsten ; Visual Cortex*

PURPOSE: By recording the electrically evoked potential (EEP) we tried to verify that focal electrical stimulation of retina sends a signal to the cortex that is similar to that elicited by light and also to investigate optimal stimulus parameters. METHODS: Five New Zealand white rabbits were placed under anesthesia. A tungsten bipolar stimulating electrode (diameter: 250 um) was placed on the vitreal surface of the retina. Cutaneous Ag/AgCl patch electrodes of VEP were used to record EEP. EEP was recorded at each stimulation. Focal visual evoked potentials (VEPs) were also recorded and compared to the focal EEP to ascertain cortical origin of the EEP, and similarities of the EEP to the VEP were determined. RESULTS: EEP recordings were elicited in 8 eyes. Current amplitudes which produced detectable responses ranged from 100 to 5000 micro A. In our best series, EEP amplitudes increased by 8 to 119 micro V in response to the current increasing from 100 to 1000 micro A. In comparing latencies of the EEP and focal VEP, the EEP latencies were 12~16 ms faster, which supports our EEP recording was done properly. CONCLUSIONS: EEPs obtained using VEP setting with adequate parameters of current duration and threshold level for the retinal implant showed that use of the EEP response is a good way to monitor the proper functioning of the retinal implant.
Anesthesia ; Electric Stimulation ; Electricity* ; Electrodes ; Electrophysiology ; Evoked Potentials ; Evoked Potentials, Visual ; Rabbits ; Retina* ; Retinaldehyde ; Tungsten ; Visual Prosthesis

PURPOSE: To analyze the clinical features of anterior ischemic optic neuropathy (AION) and to evaluate the visual prognosis METHODS: Medical records of 52 eyes in 47 patients who were diagnosed with AION from January 1991 to December 2000 were retrospectively reviewed. The clinical features, associated systemic disease, visual fields findings, and fundus findings in the patients were analyzed. RESULTS: The mean age of the patients was 55.9 years (20~81 years). Twenty-six were men (55.3%) and 21 were women (44.7%). The initial visual acuity of less than 0.1 was 24 eyes (46.2%), that of 0.1 to 0.5 was 23 eyes (44.2%), and more than 0.5 was 5 eyes (9.6%). In seasonal onset, frequency of AION during the winter was 18 eyes (37.5%). As the associated systemic diseases, 15 had diabetes mellitus (31.9%), and 27 had hypertension (57.4%). In laboratory examination, erythrocyte sedimentation rate (ESR) was elevated in 4 patients (8.5%). In fundus examination, the optic disc swelling was found in 16 eyes (30.8%), and optic disc atrophy was found in 36 eyes (69.2%). In Goldmann perimetry, the altitudinal field defect was found in 23 eyes (44.2%), most commonly. The mean follow-up period was 1.7 years (2 months ~ 9 years), and the visual acuity improved in 13 eyes (25.0%), worsened in 6 eyes (11.5%), and did not change in 33 eyes (63.5%) at the final follow-up. CONCLUSIONS: In conclusion, patients with AION showed various clinical features and overall visual prognosis is poor. Because AION is frequentely associated with systemic diseases, careful evaluation on the systemic disease is mandatory.
Atrophy ; Blood Sedimentation ; Diabetes Mellitus ; Female ; Follow-Up Studies ; Humans ; Hypertension ; Male ; Medical Records ; Optic Neuropathy, Ischemic* ; Prognosis ; Retrospective Studies ; Seasons ; Visual Acuity ; Visual Field Tests ; Visual Fields

PURPOSE: In order to evaluate the spectrum of mitochondrial DNA (mtDNA) mutations in the patients with suspected Leber's hereditary optic neuropathy (LHON). METHODS: We investigated 14 primary mtDNA mutations at nucleotide positions (nps 3460A, 4160C, 5244A, 9101C, 9804A, 10663C, 11778A, 13730A, 14459A, 14482G, 14484C, 14495G, 14498T, and 14568T) and one common secondary mutation (np15257A) in 82 Korean patients with suspected LHON. RESULTS: Among them, only three kinds of LHON mutations were identified in 60 (73%) of 82 probands, which were comprised of 46 (56%) cases with the 11778A, 13 (16%) with the 14484C, and 1 (1%) with the 3460A. None of the other mtDNA mutations was detected. Of the 60 probands with LHON positive mutations, 19 (32%) had relevant family histories. Heteroplasmy was determined in 2 (4%) of the 46 probands with the 11778A and 1 (8%) of 13 probands with the 14484C. CONCLUSIONS: In conclusion, the 11778A was the most common cause (56%), and higher prevalence of the 14484C and the lower prevalence of the 3460A were characteristic in Korean patients with LHON. Especially, the 3460A had a remarkable racial difference compared with Caucasians. Except 3460A, 11778A, and 14484C, the other mutations screened may not be involved in pathogenesis and not have a synergistic effect on the clinical expression of LHON in Koreans.
Asian Continental Ancestry Group ; DNA, Mitochondrial* ; Humans ; Molecular Biology* ; Optic Atrophy, Hereditary, Leber* ; Prevalence

PURPOSE: Extraocular muscle (EOM) consists of two layers, the global and the orbital layer, which are readily distinguished by their histopathology. This study was conducted to investigate the changes of myosin heavy chain (MHC) and MHC isoforms of the global and the orbital layers of EOM after tenotomy. METHODS: Twenty four New Zealand white rabbits were used. The rectus muscles were harvested on day 3, week 1, week 2, week 3, week 4, and week 8 after EOM tenotomy. The change of MHC amount was measured using an electrophoresis. The changes of MHC isoforms were also measured quantitatively using western blot immunostaining. RESULTS: The amount of total MHC, fast MHC isoform, and slow MHC isoform decreased maximally at 1-week after EOM tenotomy and recovered at 4-week and 8-week after tenotomy. There was no significant change in the amount of the neonatal and developmental MHC isoform. CONCLUSIONS: Fast and slow MHC isoform changed mainly due to the changes in the global layer rather than in the orbital layer after EOM tenotomy.
Blotting, Western ; Electrophoresis ; Muscles ; Myosin Heavy Chains* ; Myosins* ; Orbit ; Protein Isoforms* ; Rabbits* ; Tenotomy*

PURPOSE: To investigate the clinical outcome in patient underwent surgical correction of consecutive esotropia. METHODS: The medical records of 20 patients with at least 1 year follow-up who underwent surgical correction of consecutive esotropia from 1986 to 2001 were reviewed retrospectively. The authors investigated the deviation angle, amblyopia, diplopia before and after exotropia surgery, efficacy of occlusion on the angle of consecutive esotropia, and clinical course after consecutive esotropia surgery. RESULTS: Incidence of the consecutive esotropia was 0.9% (20 out of 2260 exotropia patients who were required surgery to correct consecutive esotropia), average age at exotropia surgery was 5 year-old, and average deviation of exotropia was 33 prism diopters (PD). There were lateral incomittancy in 4 patients, convergence insufficiency in 3 patients, amblyopia in 1 patients and no had diplopia. Monocular lateral rectus recession and medial rectus recession (R and R) was performed in 13 patients and bilateral recession in 7 patients. In most patients, even though esotropic angle was reduced by occlusion therapy, they were still esotropic. Postoperative cyclic esotropia in 3 patients, diplopia in 7 patients and amblyopia in 7 patients were developed. Surgery for esotropia was performed average 13months after surgery for exotropia, angle of esodeviation at surgery was average 31PD and amblyopia improved after surgery and occlusion in 3 eyes. There were exotropia in 15 patients, esotropia in 3 patients and orthotropia in 2 patients after surgery for consecutive esotropia. The second surgery for exotropia in 2 patients and esotropia in 1 patient were performed. CONCLUSIONS: The clinical results in surgical correction of consecutive esotropia were variable. We could not anticipate the surgical result. Careful observation and treatment for development of amblyopia is needed.
Amblyopia ; Child, Preschool ; Diplopia ; Esotropia* ; Exotropia ; Follow-Up Studies ; Humans ; Incidence ; Medical Records ; Ocular Motility Disorders ; Retrospective Studies