Axonal loss and blood flow disturbances in the natural course of indirect traumatic optic neuropathy.

BACKGROUND: Indirect traumatic optic neuropathy (TON) is an acute injury of the optic nerve associated with severe visual dysfunction, which may be a result of secondary mechanical injury and vascular disorder of the optic nerve due to trauma. We analyzed the natural course of axonal loss and blood flow disturbances in patients with indirect TON to find a possible therapeutic window. METHODS: A cohort of 54 patients with indirect TON recruited between October 2008 and October 2010 at Beijing Tongren Hospital was retrospectively analyzed. The patients were divided into no light perception group (NLP) and better than NLP (btNLP) group. Specifically, the thickness of the retinal nerve fiber layer (RNFL) measured by spectral domain optical coherence tomography (SD-OCT), and hemodynamic parameters of the ophthalmic artery (OA), central retinal artery (CRA) and posterior ciliary artery (PCA) were determined. RESULTS: Two weeks after injury, there was a statistically significant decrease in the thickness of RNFL in the btNLP group as compared with the fellow control eyes (P < 0.05). In contrast, in the NLP group, RNFL thickness slightly increased for 2 weeks following injury, then overtly reduced after 4 weeks (P < 0.05). Peak systolic velocity (PSV) of CRA was significantly decreased 4 weeks after injury (P < 0.05) in both the NLP group and btNLP group (P < 0.05). The thickness of RNFL in the NLP group was negatively correlated with PSV of CRA after 1 week of injury (P < 0.05, r = -0.962). CONCLUSIONS: SD-OCT is a useful supplement in detecting the axonal loss in TON. The dynamic change of the thickness of RNFL appears to correlate with the hemodynamic disturbances in the natural course of TON. The first 2 weeks following an injury is critical and should be considered as the therapeutic window for TON patients.

[Neurosurgical therapy of transorbital intracranial foreign bodies: review of 28 cases].

OBJECTIVE: To discuss the benefits and complications of the neurosurgical therapy in transorbital intracranial foreign bodies. METHODS: The clinical data of 28 cases of transorbital intracranial foreign bodies, metallic in 13 cases, vegetal 5 cases, and vitreous, plastic and other kinds in 10 cases, were analyzed retrospectively. Optic nerve injury was found in 13 cases, orbital apex syndrome in 11 cases; CSF rhinorrhea in 13 cases, CSF orbital leak in 3 cases, and hemiplegia in 2 cases. All the patients underwent head CT scan, and orbital horizontal and coronal CT scan. The patients with metallic foreign bodies had DSA exams, and the non-metallic cases had MRA scans. 22 cases had orbital-frontal craniotomy and foreign body resection, and 6 cases had direct foreign body extraction. All the cases received antibiotic and nerve nutritional therapy postoperatively. RESULT: The cases in which the foreign bodies came from the orbital roof into the skull recovered well postoperatively; and the cases in which the foreign bodies came from the superior orbital fissure into the skull showed hemiplegia (n = 2) or orbital apex syndrome (n = 6) postoperatively. CONCLUSION: Transorbital intracranial foreign body should be diagnosed in early stage to avoid missed diagnosis. Omission should be avoided during resection of the foreign body. The relationship between the foreign body and internal carotid artery should be examined carefully before the extraction. Direct extraction of foreign body causes less injury, and patients' condition should be followed up.

[The prevalence and its effective factors of primary angle-closure glaucoma in defined populations of rural and urban in Beijing].

OBJECTIVE: To investigate the prevalence of primary angle-closure glaucoma (PACG) of urban and rural residents in Beijing, China. A quantitative comparison was made based on the data collected from this epidemiological survey. We also identify some of the most typical risk factors associated with PACG. METHODS: Glaucomatous screening examination was applied to specific age group populations (aged 40 and older) in the defined district of Beijing and its remote rural county, from June to October, 2001. There are 4451 subjects in all, 1980 rural subjects and 2471 urban subjects, 1939 males and 2512 females. The screen and diagnostic methods used in this survey included van Herick methods and gonioscopy examination to estimate the peripheral depth of the anterior chamber, visual acuity, intraocular pressure, refraction status, stereoscopic fundus photography, and threshold-related visual field tests. Subjects regarded as suspected glaucoma and glaucoma patients are reexamined with standard glaucomatous examination. RESULTS: The response rate of rural and urban population is 79.6% (1980/2488), 87.1% (2471/2836), respectively. The prevalence of PACG (in aged 40 years or older population) resulted from this survey was 1.2% (95% CI 0.9% - 1.5%). However, the prevalence was different between urban and rural residents, 1.1% (95% CI 0.8% - 1.4%) vs. 1.6% (95% CI 1.2% - 2.0%). The prevalence of PACG in female was more than that in male, 1.7% (95% CI 1.3% - 2.1%) vs.0.8% (95% CI 0.5% - 1.1%). A drastic increase in prevalence of PACG with age increase was identified in both survey sites, however, this increase in rural subjects (aged 60-69 years group) occurred ten years earlier than those from urban subjects (aged more than 70 years group). Compared to urban residents, rural residents showed higher prevalence of unilateral low vision (39.3% vs. 20.6%) and blindness (28.6% vs. 14.7%). This survey also confirmed that, as people aging, refraction status became hyperopia, the depth of peripheral anterior chamber became narrow. In the different age groups, female and male groups, the changes of refraction status and the depth of peripheral anterior chamber paralleled the prevalence of PACG. CONCLUSIONS: The prevalence of PACG was obviously different in different groups. This could due to several factors including gender, age, change of refraction status and chamber angle as well.

[Endoscopic decompression of optic canal].

OBJECTIVE: To evaluate the effectiveness of endoscope in the treatment of optic nerve injury. METHODS: Thirteen patients with fracture at the inner and lower walls of optical canal underwent endoscopic decompression. The posterior 1/3 of the middle concha, the posterior ethmoid sinus and sphenoid sinus were opened, chips of bone and old hematocele were scavenged, and the optic ring of the optic canal was polished; however, the sheath of the optic nerve remained intact. In 2 cases with the dura broken at the cranial part of optic nerve, the broken site was covered with mucosa of middle concha, and the sphenoid sinus and the middle nasal meatus were covered with oil ribbon gauze. Three days after the operation, the ribbon gauze was pulled put, however, if cerebro-spinal fluid leakage was suspected, the ribbon gauze was pulled out 7-10 days after. After the operation the visual acuity improvement reaching one grade or more and improvement of visual field were defined as effective. RESULTS: Five of the 6 patients without light perception before the operation showed improvement in visual acuity. The other 7 patients with residual visual acuity all recovered to different extents. CONCLUSION: A mini-invasive surgery, decompression of optic canal with endoscope is effective in decompressing optic nerve, decreasing the injury of optic nerve, and the patients recover quickly after operation.

[Experimental study of the biocompatible and osteoinductive behavior of the hydroxyapatite/ultra-high molecular weight polyethtlene composite].

OBJECTIVE: To compare the biocompatibility and osteoinductive behavior of HA (hydroxyapatite) and HA/UHMWPE (ultra-high molecular weight polyethtlene) composite in orbital implantation. METHODS: Osteoectomy of the upper orbital rim was perform on 24 adult New Zealand rabbits. The animals were randomly divided into 4 groups with 6 of each. The HA, HA/UHMWPE composite or UHMWPE (10 mm x 10 mm x 3 mm in size) was implanted to the upper orbital defect of the animal in respective group. Animals were sacrificed at 1, 4, 8, 12 weeks. Histopathologic sections of the implants were evaluated and compared with light and transmission electron microscopy study. RESULTS: During the experimental period of 12 weeks, there was no implant extrusion or displacement. In the groups of HA and HA/UHMWPE composite, vascular ingrowth and fibroblasts were observed shortly and osteocytes were seen at 8 weeks. Calcium deposition of the implants showed a laminar fashion at 12 weeks. In the group of UHMWPE, fibrous membranes were seen around the implant at 1 week. Transmission electron microscopy study showed that in the HA and HA/UHMWPE groups, fibroblasts and vascular ingrowth could be seen, but osteocytes were not observed. CONCLUSION: HA/UHMWPE composite demonstrated biocompatibility and osteoinductive property. It would be a good substitute for bone, particularly for orbital bone.

[The prevalence and its screening methods of primary open angle glaucoma in defined population-based study of rural and urban in Beijing].

OBJECTIVE: The purpose of the study is to determine the prevalence of primary open-angle glaucoma (POAG) in persons aged 40 or above in Beijing, China. METHODS: From June 2001 to October 2001, the screening population was identified by a door-to-door census in five metropolitan resident areas in the north of Beijing and three villages in a county south to Beijing. The screening included visual acuity, frequency doubling perimetry (FDP, C-20 screening program), non-contact tonometry, slit lamp microscopy, anterior chamber depth (Van Herick method), and fundus photography. The suspect glaucoma and definite glaucoma patients were asked to have an examination of Octopus 1-2-3 perimetry (G1X TOP threshold program), repeat tonometry, gonioscopy and fundus stereo-photography at Beijing Tongren Hospital. RESULTS: There were 4451 subjects who were examined at the study sites. The response rates in rural and urban were 79.58% and 87.13%, respectively. In this 40 years-old or above population, the prevalences of POAG were 1.97% in rural men, 2.07% in urban men, 1.04% in rural women and 1.42% in urban women. In this study, 92.30% POAG patients in rural and 87.30% POAG patients in urban were new diagnosed cases. The prevalence of POAG increased with age and the change was exponential. In 50% POAG patients first IOP measurement was less than 21 mm Hg (1 mm Hg = 0.133 kPa). The prevalence of monocular eye blindness was 15.40% and 10.90% in rural and urban, respectively. CONCLUSIONS: Owing to use fundus photography and integrated evaluation of optic disc, it is possible to diagnose in earlier stage of POAG. This study identifies more patients with POAG than any previous population-based studies of China, and is similar to other studies of Asia such as in India and Singapore. The reason of lower POAG prevalence in rural women than in urban may be that the anterior chamber depth of rural women is shallower than that of urban women. It may cause difficult to differentiate the chronic primary angle closure glaucoma from POAG at screening sites, so the part POAG patients may be included in primary angle closure glaucoma patients.

[Traumatic Rollel's syndrome treated with decompression of orbital apex].

OBJECTIVE: To observe the efficiency of decompression of orbital apex operation for the treatment of traumatic Rollel's syndrome. METHODS: Eleven patients with Rollel's syndrome were operated using two different approaches of decompression of orbital apex according to the location of the lesion. Five cases were treated by trans-frontal approach and 6 cases by trans-pterion approach. For the purpose of evaluation, the postoperative outcome of visual acuity was classified into five grades: Non-light perception, light perception, hand motion, finger counter and acuity chart. The visual acuity improvement reaching 1 grade or more was defined as effective and less than 1 grade as inefficient. The improvement of nerve injuries in superior orbital fissure was also evaluated, patients with recover of 2 or more nerves was defined as effective. RESULTS: Visual acuity: 3 cases (50%) were classified as effective in non-light perception group, the remaining 5 cases who had residual vision before operation all improved to various extents. The eye position in cases with exophthalmos was return to normal after operation. Injured nerves were recovered in all 11 cases. CONCLUSIONS: Decompression of orbital apex is an effective treatment for patients with Rollel's syndrome and the craniotomy approach can treat the combined brain injury. The recovery after operation is correlated with the timing of surgery, the approach of the operation and also related with the severity of the nerve injury.