主眼外斜视进行双侧外直肌后退术与单侧后退-切除术

PURPOSE: To compare the surgical outcomes of bilateral lateral rectus recession and unilateral recess-resect (RR) procedure on the nondominant eye for the patients of exotropia with a dominant fixating eye. DESIGN: Prospective randomized comparative clinical trial. METHODS: One hundred twenty four patients of exotropia with an invariably fixating eye were enrolled to this study. Patients were assigned randomly to two groups, those who underwent bilateral lateral rectus (BLR)-recessions (BLR group) or unilateral RR procedures on the nondominant eye (RR group); surgical outcomes were compared. An outcome was considered satisfactory if there was between 10 prism diopters of exophoria/tropia and 10 prism diopters of esophoria/tropia at 6 months after surgery. RESULTS: In the BLR group, 28 of the 58 patients (48.3% ) had a satisfactory outcome, and 30 patients (51.7% ) had recurrence. There was no case of overcorrection in the BLR group. In the RR group, 55 of the 66 patients (83.3% ) had a satisfactory outcome; 6 patients (9.1% ) had recurrence, and 5 patients (7.6% ) were overcorrected (P < .001, Fisher’s exact test). All overcorrected patients in the RR group had poor stereoacuity and constant exotropia before the operation. The cumulative probability of surgical success was significantly higher in the RR group than in the BLR group (P=.012, log rank test). CONCLUSIONS: In the patients with exotropia with a dominant eye, the unilateral RR procedure resulted in a better outcome than BLR recession surgery. But, the overcorrection rate was significantly higher in the unilateral RR procedure group, especially in those patients with a poor preoperative stereopsis status and constant exotropia.

视动力反应测量有眼部疾病患者的客观视力

PURPOSE: To investigate the efficacy of optokinetic nystagmus (OKN) suppression and induction methods for the objective estimation of visual acuities in patients with various ocular diseases. DESIGN: Prospective, descriptive study. METHODS: One hundred seventy-three eyes of 89 patients aged between 27 and 75 years who registered at our institution from January to December 2004 were prospectively enrolled onto this study. Ocular diseases included generalized retinal diseases (47 eyes), media opacity (32 eyes), refractive errors (31 eyes), glaucoma (27 eyes), maculopathies (26 eyes), and optic neuropathies (10 eyes). Horizontal optokinetic stimuli were presented on a 17-inch monitor screen at a distance of 40 cm from the subject in a dark room. Horizontal eyemovements were recorded in each eye separately by infrared oculography. Objective visual acuities measured by using OKN suppression or induction methods were compared with subjective visual acuity assessments. The logarithm of minimal angle of resolution visual acuity was 1.03, and ranged from -0.08 to hand movement. RESULTS: Linear regression identified minimum stripe stimuli required to induce OKN by using the OKN induction method, and the minimum dot size required to suppress OKN was found to be correlated with subjective visual acuity (P < .01). The induction method was useful in patients with visual acuities of 20/60 or worse, and the suppression method was useful in patients with visual acuities of 20/200 or better. CONCLUSIONS: Combined use of the OKN induction and suppression methods provides a satisfactory means of determining objective visual acuity.

常染色体显性遗传视神经萎缩的线粒体DNA含量减少

Background: Autosomal dominant optic atrophy (ADOA) is the commonest form of i nherited optic neuropathy. Mutations in the OPA1 gene encoding a dynamin-relate d mitochondrial protein underlie ADOA and may perturb the biogenesis and mainten ance of mitochondria. Objective: To investigate the mutation spectrum of the OPA 1 gene and assess alterations in mitochondrial content caused by OPA1 mutations. Methods:Sixteen Korean patients with clinically suspected ADOA were studied. Th e mutation spectrum of the OPA1 gene was analyzed by PCR single-strand conforma tion polymorphism and sequencing, and mitochondrial DNA (mtDNA) content was quan tified by real-time PCR. Results: Eight different mutations were found, includi ng five novel mutations. Quantitative real-time PCR analysis showed excellent l inearity and precision for the determination of mtDNA copy numbers. The number o f mtDNA copies per cell in patients with OPA1 gene mutations(ages 7 to 40) was s ignificantly lower than those in all normal control subjects (p=0.037), particul arly lower than in normalcontrol subjects ages 10 to 39 (p=0.022). Conclusion: T he mutation spectrum of the OPA1 gene disclosed marked genetic heterogeneity and the mitochondrial DNA content was found to be lower in autosomal dominant optic neuropathy, which provides direct evidence for a pathogenetic role of mutations of the OPA1 gene.

间歇性外斜视手术最大矫正角度

Purpose: To evaluate the safety of the approach based on the notion that the s urgical dose for intermittent exotropia should be based on the largest angle eve r measured. Design: Prospective case series of 33 patients. Methods: A total of 33 patients with intermittent exotropia, in whom angles of misalignment at dista nce or near showed a difference of 15 prism diopters (PD) or more among visits, were included. All the patients were treated by bilateral lateral rectus recessi on by the same surgeon (JMH), and all were followed up for a minimum of 6 months postoperatively. Short-and long-term surgical results after the initial proce dure for intermittent exotropia were analysed. Results: The short-term average result at a postoperative 1 week was 9.3 PD esotropia at distance (range 30 esot ropia-16 exotropia). The long-term average results postoperative 6 or 9 months were 4.8 PD exotropia at distance (range 12 esotropia -30 exotropia). At the l ast follow-up, no overcorrection over 2 PD esophoria at distance was found, and 9 PD of intermittent esotropia and esophoria at near was observed in two patien ts, respectively. Conclusions: The strategy of surgical dose for intermittent ex otropia based on the largest angle ever measured did not result in overcorrectio ns and is believed to be safe.

磁共振成像技术研究先天性纤维化综合征和协同肌分离患者的先天动眼神经发育不全及外展神经缺失

Objective: There is only one neuropathologic report of congenital fibrosis of the extraocular muscles (CFEOM), and none of synergistic divergence. The aim of this report was to study the oculomotor nerve and the abducens nerve in 2 such p atients with magnetic resonance imaging. Design: Observational case reports. Met hods: Ophthalmologic examination and thin-sectioned magnetic resonance imaging across the brainstem level were performed in 2 patients with CFEOM and synergist ic divergence. To confirm the accuracy of the procedure, we compared the results obtained with those of a control group of 40 individuals using the same techniq ue. Main Outcome Measures: The oculomotor nerve and the abducens nerve on magnet ic resonance imaging. Results: Magnetic resonance imaging disclosed bilateral hy poplasia of the oculomotor nerve in both patients, and absence of the abducens n erve on the affected side of synergistic divergence. The oculomotor and abducens nerves were observed in 80 of 80 eyes (100%) screened as controls. C onclusions: In both patients with CFEOM and synergistic divergence, the oculomot or nerve was hypoplastic bilaterally, and the abducens nerve was absent on the s ide exhibiting synergistic divergence.

颅面裂患者的特征性眼部表现

Purpose: To identify the characteristic ocular findings in patients with craniofacial cleft (CFC). Methods: Ophthalmologic examination wa s performed for a 16-year-old girl with no. 3 CFC and a 3-year-old boy with no. 5 CFC. Results: Exotropia was found in the 3-year-old boy with no. 5 CFC i nvolving the lateral orbit, and esotropia in the 16-year-old girl with craniof acial cleft no. 3 involving the medial orbit. Hypotropia, lower eyelid coloboma, amblyopia and an absence of stereopsis were common to both patients. Visual acu ity was improved from hand motion to 20/30 by means of occlusion therapy for amb lyopia in the 3-year-old boy. Strabismus surgery resulted in exophoria of 8 pr ism diopters (PD) in the 3-year-old boy and left esotropia of 8 PD in the 16- year-old girl. Conclusions: Amblyopia, hypotropia, esotropia (no. 3) and exotro pia (no. 5) should be verified in cases of CFC nos. 3 and 5. Ophthalmologic exam ination and early intervention for amblyopia may be mandatory for patients with CFC involving the orbit.

Duane眼球后退综合征的类型与外展神经存在与否的关系

To analyze whether the presence of the abducens nerve might depend upon the ty pe of Duane’s retraction syndrome (DRS). Observational case series. Sixteen pat ients with type 1 DRS, 2 patients with type 2 DRS, and 5 patients with type 3 DR S. Ophthalmologic examination and thin-sectioned magnetic resonance imaging (MR I) at the brain stem level were performed in 23 DRS patients. To confirm the acc uracy of the procedure, we compared the results obtained with those of a control group of 30 individuals using the same technique. Examination of ductions and v ersions and the presence of the abducens nerve on MRI. The abducens nerve on the affected side could not be observed using MRI in 18 (100%) of 18 eyes (16 pati ents) with type 1 DRS and in 3 of 5 eyes with type 3 DRS. Conversely, the abduce ns nerve was observed in 2 of 2 eyes with type 2 DRS and 2 of 5 eyes with type 3 DRS. The abducens nerve was observed in 60 (100%) of 60 eyes screened as contr ols. The abducens nerve on the affected side was absent in type 1 DRS patients a nd some type 3 DRS patients, but present in type 2 DRS patients as well as in so me type 3 DRS patients. In terms of the presence or absence of the abducens nerv e, type 1 and type 2 DRS were homogenous, and type 3 DRS was heterogenous.