Difference of anterior and posterior orbital development in patients with congenital microphthalmia: a retrospective cohort study from China.

AIM: To evaluate volume differences between anterior and posterior orbit and demographic characteristics of Chinese patients with congenital microphthalmia. METHODS: A retrospective cohort study, involving 169 unilateral congenital microphthalmia patients aged between 1 and 57 years old was conducted. Three-dimensional images of the orbit were generated from past CT scans, and digital orbital volume comprehensive measurement was done. The measured data included orbital volume (OBV), posterior orbital volume (POV), orbital width (OBW), orbital height (OBH), orbital depth (OBD), and posterior orbital area ratio. RESULTS: Significant differences were observed among OBV, POV, OBW, OBH, and OBD of the affected and unaffected eyes in different age-based groups (all P<0.001). Among them, OBH had the greatest different. The mean microphthalmic to contralateral ratio (MCR) of OBV, POV, OBW, and OBH continuously increased from 1 to 3 years old, whereas the MCR of POV decreased from 3 to 17 years old. The MCR of OBD was not found to be correlated to age. There was no significant difference between OBV, POV, OBW, and OBH in ages from 13 years old to adulthood (all P>0.05). The difference in posterior orbital area ratio between the affected and unaffected groups was not statistically significant (P>0.05). CONCLUSION: OBH is maximally affected, whereas OBD is minimally affected by microphthalmia. Posterior orbital retardation began 2y prior to orbital retardation and occurred at 3 years old in the affected eye, suggesting that intervention therapy should be done before the age of 4.

Congenital Monocular Strabismus Fixus.

PURPOSE: To investigate the clinical characteristics and magnetic resonance imaging (MRI) findings of the extraocular muscle and ocular motor nerves in congenital monocular strabismus fixus. METHODS: The retrospective observational case series of three patients with congenital monocular strabismus fixus were reviewed between January 1, 2006, and December 31, 2016. Ophthalmologic examination and thin-sectioned MRI of the ocular motor nerve and the orbit were performed on the three patients. RESULTS: Three patients presented with unilateral non-progressive strabismus fixus with marked limitations of movement in all directions since birth. Of the three patients, one presented with esotropia, one with a large degree of exotropia and hypertropia, and one with an almost normal primary position. All three patients had normal ocular motor nerves, but adherences among the extraocular muscles, posterior Tenon's capsule, and the globe within the muscle cone on MRI. Two patients underwent strabismus surgery, but there were no postoperative improvements in the primary position and eye movements. CONCLUSIONS: Extensive adherences among the extraocular muscles, posterior Tenon's capsule, and globe may partially explain the cause of congenital monocular strabismus fixus and why strabismus surgery was ineffective. The findings further highlight the importance of MRI in detecting and characterizing atypical forms of strabismus. [J Pediatr Ophthalmol Strabismus. 2018;55(6):363-368.].

[Vertical retraction syndrome caused by anomalous orbital structures].

OBJECTIVE: To described the clinical feature and MRI imaging of six children with vertical retraction syndrome. METHODS: Six children with unilateral vertical retraction syndrome between 15 months and 8 years of age, mean age was (5.01 ± 1.27) years old. Strabismus examination included diopter, prism diopters, eye movement examination, binocular vision and fundus examination. Imaging of the ocular motor nerves at the brainstem was performed in 0.8 mm thickness image planes using 3D-FIESTA sequence, the orbits were imaged with FSE T1, T2WI using surface coils, and within 2.0 mm thick planes. RESULTS: Four children showed hypertropia, characterized by limited depression, a light retraction of the globe during downward gaze and eyelid lag. The MRI imaging showed anomalous orbital structure in the superonasal quadrant that between medial rectus and superior rectus or adjacent to the superior rectus. Two children showed intermittent exotropia, characterized by limited elevation, retraction of the globe and narrowing of the palpebral fissure during upward gaze. The MRI imaging showed anomalous orbital structure was present in the inferotemporal quadrant, one originate in inferior rectus and another close to the lateral rectus. CONCLUSION: Anomalous orbital structures are a main cause of vertical retraction syndrome. The presence of specific unusual eye movement and MRI imaging may assist in diagnosis. When the eyelid lag was found since the early age, anomalous orbital structures were implied.

[Theoretic explanation about visual disorder induced by fibrous dysplasia of skull: pressure disequilibrium between lamina cribrosa].

OBJECTIVE: To investigate the causes for changes in optic nerve head and visual impairment caused by fibrous dysplasia (FD) of optic canal stenosis. METHODS: A total of 12 FD patients, diagnosed by CT, received the fundus and optical coherence tomography (OCT). Those with FD involving optic canal underwent decompression. The examination of OCT showed that lamina cribrosa located at the top was the exposure factor for retinal pigment epithelium (RPE). There were decreased vision or edematous optic nerve and atrophic lesion. Odds ratio was calculated by Fisher's exact test. RESULTS: The examination of CT showed the results of optic canal stenosis caused by lesions involving 18 sides: 8-sides with normal vision. Among which, 6 showing that lamina cribrosa was located below RPE and a lamina cribrosa plate near RPE at follow-up, 1 side OCT showing lamina cribrosa above RPE with normal optic nerve; a lateral lamina cribrosa was located above RPE with edematous optic nerve. Visual impairment at 10 sides, normal papillary 2 sides, atrophic papillary 8 sides, OCT showed that lamina cribrosa was located above RPE, postoperatively OCT showed that lamina cribrosa below with 7 sides having improved visual acuity. Fisher's exact test was performed (P = 0.000, odds ratio = infinity). CONCLUSION: The optic canal stenosis causes a rising pressure of lamina cribrosa zone to shift above RPE. The channel becomes distorted so as to squeeze and cut the ganglion cell axons of optic nerve, block the axoplasmic transport and result in blood circulation disorder. The above factors are the etiologies of visual impairments. Postoperatively lamina cribrosa zone pressure drops so that depressed lamina cribrosa and channel deformation recover and visual acuity improves.

[Correlation between upper airway soft tissue 3-D measurement and the severity of obstructive sleep apnea hypopnea syndrome].

OBJECTIVE: To investigate the correlation between upper airway CT measurement value and severity of patients with obstructive sleep apnea hypopnea syndrome (OSAHS). METHODS: The upper airway of 82 patients with OSAHS were scanned by CT during normal respiration. The 3-D CT measurement were made in lateral and anterior-posterior diameters, cross-section areas and volumes of retropalatal and retroglossal region. RESULTS: The lateral diameters and cross-section areas of every research plane were negatively correlated with apnea and hypopnea index (AHI), in particular the minimal lateral diameter of the whole airway (r = -0.558, P < 0.01). For volumes, AHI decreased with larger volume of nasal cavity, nasopharyngeal cavity and velopharyngeal cavity (P < 0.05 or P < 0.01). The negative correlation between AHI and proportion of cavity volume to the bone frame of velopharyngeal area and whole upper airway were significant (P < 0.05 or P < 0.01). But the correlation between AHI and volume of velopharyngeal soft tissue, the proportion of soft tissue to the bone frame volume of velopharyngeal area, the proportion of soft tissue to the bone frame volume of whole upper airway was significant positive, as well as the correlation between AHI and the proportion of soft tissue to the cavity volume of velopharyngeal area and whole upper airway (P < 0.05 or P < 0.01). CONCLUSIONS: To evaluate the severity of OSAHS with upper airway CT measurement, there is no difference between 3-D parameters and 2-D parameters. In terms of the whole airway, the lateral diameters, the cross-section area, the cavity volume, the soft tissue of the upper airway, are meaningful to evaluate the severity of disease, in particular the measurement of velopharyngeal area.