Correlation of retrobulbar perfusion deficits with glaucomatous visual field defects.

PURPOSE: This study is to evaluate the correlation between retrobulbar perfusion deficits and glaucomatous visual field defects. METHODS: Eighty-four patients with glaucoma and 17 normal subjects serving as controls were selected. Color Doppler imaging (CDI) was used to measure the changes in blood flow parameters in the retrobulbar ophthalmic artery (OA), central retinal artery (CRA), and short posterior ciliary arteries (SPCAs). Visual field testing was performed using a Humphrey perimeter, categorizing the visual field deficits into four stages according to the Advanced Glaucoma Intervention Study (AGIS) scoring method. Subsequently, the correlation of retrobulbar hemodynamic parameter alterations among glaucomatous patients with varying visual field defects was examined. RESULTS: The higher the visual field stage, the lower the peak systolic velocity (PSV) of the OA, CRA, and SPCAs in glaucomatous patients. The CRA had the highest sensitivity to changes in its PSV. The PSV of the temporal SPCA (TSPCA-PSV) was lower in advanced glaucoma than in early-stage glaucoma. The PSVs of the OA, CRA, and TSPCA, as well as the resistance index of the CRA (CRA-RI), were positively correlated with the visual field index and the mean deviation. Except for that of OA, the PSV of the retrobulbar vessels was negatively correlated with the pattern standard deviation (PSD). The OA-PSV and end-diastolic velocity (EDV) of the CRA and TSPCA were lower in patients with superior visual field defects than in those with inferior visual field defects. CONCLUSIONS: Greater severity of visual field defects corresponded to poorer retrobulbar blood flow in glaucomatous patients. Patients suffered significant perfusion impairments in the CRA at the early stage, accompanied by SPCA perfusion disorder at the advanced stage. The presence of a bow-shaped defect in the superior or inferior region of the visual field in moderate-stage glaucoma was closely correlated with retrobulbar vascular EDV. TRIAL REGISTRATION: ChiCTR2200059048 (2022-04-23).

Characterization of the position of the extraocular muscles and orbit in acquired esotropia both at distance and near using orbital magnetic resonance imaging.

PURPOSE: Age-related distance esotropia (ARDE) involves acquired esotropia at distance and phoria at near. However, distance-independent esotropia (DIE) exists esotropia both at distance and near. Thus, we examined the orbital magnetic resonance imaging (MRI) findings for DIE to assess differences in its characteristics. METHODS: This study was a retrospective case-control study. We evaluated the efficacy of the standard coronal MRI in patients with acquired esotropia and control patients with optic neuritis. Cases with strabismus in the control group were excluded. DIE was defined as having esotropia both at distance and near, and an angle of more than 10 prism diopters at near. The condition of the lateral rectus-superior rectus band, position of rectus muscles, and the volume ratio of the globe to the whole orbit (G/WO) were examined. RESULTS: The DIE group consisted of 12 eyes of 6 patients (77.3±7.7 years); ARDE group, 38 eyes of 19 patients (73.1±6.8 years); and control group, 34 eyes of 17 patients (70.9±4.3 years). The ratio of abnormality of the lateral rectus-superior rectus bands was higher in the DIE and ARDE groups than in the control group (p<0.01). The vertical angle of the lateral rectus deviated downwards in the control (-7.5±5.1°), ARDE (-12.2±9.1°), and DIE groups (-18.8±5.7°) (p<0.05). The tilting angle of the lateral rectus was tilted temporally in the control (-12.2±9.1°), ARDE (-20.0±8.6°) and DIE groups (-28.6±5.4°) (p<0.01). G/WO was higher in the DIE (0.28±0.01) and ARDE groups (0.27±0.02) compared to the control (0.25±0.03) group (p<0.01). CONCLUSION: In comparison with the ARDE and control groups, the DIE group presented with abnormalities of the lateral rectus-superior rectus band, malposition of the lateral rectus, and differences in the G/WO. The DIE group showed a more severe form of ARDE.

Percentage of Myeloid Dendritic Cells in Peripheral Venous Blood Is Negatively Related to Incidence of Graves' Orbitopathy.

The aim of the study was to evaluate the distribution of blood dendritic cells (DCs) in patients with Graves' orbitopathy (GO) and to assess the influence of methylprednisolone therapy on subsets of peripheral blood mononuclear cells (PBMCs). Peripheral blood DC subsets were analyzed by flow cytometry in patients with active GO (n = 17), inactive GO (n = 8), and Graves' disease (GD) without GO (n = 8) and controls (n = 15); additionally, in patients with active GO (n = 17), analyses were done at three time points, i.e., before methylprednisolone treatment and after 6 weeks and after 12 weeks of the treatment. Percentage of myeloid DCs (mDCs) in PBMC fraction was significantly lower in patients with both active and inactive GO, compared to patients with GD without GO and controls (p < 0.05). In addition, mDCs were also documented to be an independent factor negatively associated with GO, however without essential differences between active and inactive phases. On the other hand, we did not observe any changes in the percentage of DCs after methylprednisolone therapy (p > 0.05). In the present study, we have succeeded to firstly demonstrate-according to our knowledge-that blood mDCs are negatively related to GO incidence.

Ophthalmic and orbital considerations in the evaluation of skull base malignancies.

INTRODUCTION: The orbital contents, afferent and efferent visual pathways, and the cranial nerves involved in eye movement, corneal sensation and eyelid closure traverse the skull base, a region bounded by the intracranial cavity, the paranasal sinuses, and the deep spaces of the face and head. As such, tumors from above or below have potential to affect some aspect of the visual system. METHODS: We discuss here the clinical ophthalmologic and orbital considerations in the evaluation of patients with these tumors, as well as the ophthalmic sequelae of treatment with radiation or surgery (or both). And for the surgeon, we discuss the ophthalmic and orbital considerations in surgical planning, the role of the orbital surgeon in skull base surgery, and briefly discuss transorbital approaches to the skull base. RESULTS AND CONCLUSION: Ophthalmic and orbital dysfunction may be the main source of disability in patients with skull base malignancy; it is thus incumbent on those who manage patients with tumors of this region to be aware of the ophthalmic, neuro-ophthalmic and orbital manifestations, so as to best tailor therapy and monitor treatment outcomes.

Enhanced orbital adipogenesis in a mouse model of T-cell-mediated autoimmunity, zymosan A-treated SKG mice: Implications for Graves' ophthalmopathy.

Inflammation and remodelling of orbital tissue associated with enhanced adipogenesis commonly occur in Graves' ophthalmopathy (GO), however, the underlying mechanisms that link immune cells and adipocytes in orbital inflammation are not well-known. The primary aim of this study was to elucidate how a genetically determined shift in the T-cell repertoire toward self-reactive T-cells could drive orbital adipogenesis. To induce the T-cell-mediated autoimmune response, SKG mice were intraperitoneally injected with zymosan A once at 8 weeks of age. After three months, orbital magnetic resonance imaging (MRI), histopathologic studies, and in vitro analyses were performed to evaluate inflammation and adipogenesis. The eyes of the zymosan A-treated SKG mice displayed proptosis and blepharitis. A detailed analysis of orbital adipose tissue showed enhanced orbital adipogenesis and cellular infiltration compared to controls. In addition, increased secretion of adipokines and other cytokines in the periorbital tissue was observed, together with elevated serum concentration of inflammatory cytokines. Orbital adipogenesis was enhanced in zymosan A-treated SKG mice, a novel mouse model for GO-like inflammatory adipose phenotypes most likely induced by T-cell mediated autoimmune responses. This mouse model gives us the opportunity to examine the underlying molecular mechanisms of enhanced adipogenesis in GO, ultimately providing a potential therapeutic target alternative to conventional GO treatment.

Reconstruction of Medial Wall Blowout Fracture Defect with a Combination of Resorbable Meshed Plate and Cancellous Bone Allograft.

BACKGROUND: Various materials are available for the reconstruction of bone defects in cases of medial wall blowout fracture. This study was conducted to assess the efficacy of the combination of a resorbable meshed plate and cancellous bone allograft. METHODS: From March 2014 to March 2017, a total of 111 patients were evaluated. Sixty-three patients received reconstruction surgery with porous polyethylene plates (control group) and the other forty-eight patients underwent operation with a resorbable meshed plate plus allogenic cancellous bone (combined group). The results were assessed by exophthalmometric measurements, width, and volume discrepancies as compared with the unaffected orbit, and operation time. RESULTS: The difference in exophthalmometric measurements between the affected and unaffected orbits were 0.94 ± 0.70 mm in the control group and 1.05 ± 0.73 mm in the combined group without statistical significance (p = 0.425). In the analysis of computed tomography images, the width discrepancy was 1.55 ± 0.86 mm and 1.08 ± 0.69 mm, respectively (p = 0.003); however, the volume discrepancy demonstrated no statistically significant difference (2.58 ± 1.40 cm3 versus 2.20 ± 1.80 cm3; p = 0.209). Operation time was significantly shorter in the combined group as compared with the control group (43.0 ± 7.0 versus 38.3 ± 7.0 minutes; p = 0.001). CONCLUSION: The combination material composed of resorbable meshed plate and cancellous bone allograft made reconstruction surgery of medial wall blowout fracture easier and quicker to perform with long-lasting results.

Therapeutic Effects of Short Cyclic and Combined Epitope Peptides in a Long-Term Model of Graves' Disease and Orbitopathy.

BACKGROUND: Cyclic peptides derived from some cylindrical loops of the leucine-rich repeat domain (LRD) of the thyrotropin receptor (TSHR) have been shown to treat disease manifestations in a mouse model of Graves' disease during a long-term protocol of four-weekly immunizations with adenovirus coding for the TSHR A-subunit (Ad-TSHR289). METHODS: In a follow-up study, two additional cyclic peptides were tested, which were shortened in order to obtain additional information on the minimally involved epitopes and to enable easier production conditions. In addition, a linear peptide was tested, which mimics parts of three loops of the native TSHR LRD structure, and is potentially able to block the discontinuous epitopes of anti-TSHR antibodies. RESULTS: The novel peptides markedly reduced thyroid size, serum thyroxine levels, retro-orbital fibrosis, and tachycardia in Ad-TSHR289-immunized mice. In immunologically naïve mice, administration of the peptides did not induce any immune response. CONCLUSIONS: In summary, novel cyclic peptides mitigate many clinical findings in a mouse model of established Graves' disease and orbitopathy, and may therefore provide an additional therapeutic option compared to existing drugs or interventions.

Ocular Compartment Syndrome and Lateral Canthotomy Procedure.

BACKGROUND: Ocular compartment syndrome (OCS) is a serious ophthalmological emergency that should be diagnosed and treated immediately to prevent permanent loss of vision. It is usually caused by a retro-orbital bleed that will subsequently increase intra-orbital pressure and threaten the patient's vision. Lateral canthotomy and cantholysis is a minor bedside procedure using simple equipment that is readily available in emergency departments, and the aim of such a procedure is to free the eye globe from its lateral attachment to the bony orbital wall and allow more eye protrusion and hence reduce intra-orbital pressure and save the patient's sight. The case we present describes a 42-year-old man who presented with facial injuries following an alleged assault and in whom a computed tomography scan of the head showed a retro-orbital hemorrhage. The patient had subtle signs of increased intra-orbital pressure for which lateral canthotomy and cantholysis was indicated. DISCUSSION: OCS is an ophthalmological emergency that can present with subtle signs of increased intraocular pressure that can lead to irreversible loss of vision if not treated with a simple bedside operation called lateral canthotomy and cantholysis within a specific time frame. We explore the pathophysiology and presentation of OCS and how to perform the lateral canthotomy with cantholysis procedure. CONCLUSIONS: The aim of this case presentation is to highlight the importance of diagnosing OCS as an ophthalmological emergency and discuss how to perform the sight-saving procedure.

Cerebral Venous Thrombosis: An Uncommon Cause of Papilledema on Bedside Ocular Ultrasound.

BACKGROUND: Cerebral venous thrombosis (CVT) is a rare, difficult-to-diagnose form of venous thromboembolic disease and is considered a type of stroke. Its presentation is highly variable and may be easily confused for more common and less debilitating or life-threatening diagnoses such as migraine, seizure, or idiopathic intracranial hypertension. CASE REPORT: A 25-year-old woman presented with a complaint of bifrontal throbbing headache and blurry vision. A bedside ultrasound of the orbit suggested increased intracranial pressure. A subsequent computed tomography venogram demonstrated a left transverse sinus thrombosis. The patient was started on enoxaparin and admitted for bridging to warfarin and evaluation for hypercoagulable state. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: CVT is a rare form of stroke that carries a high rate of mortality and morbidity and masquerades as more common and benign diagnoses. Emergency department bedside ultrasound of the orbit may make the diagnosis of CVT more attainable by identifying patients with increased intracranial pressure.

Orbital Fat Injection: Technique and 5-Year Follow-Up.

BACKGROUND: Orbital volume loss, early or late, is common after placement of an orbital implant or dermis fat graft, and there is currently no satisfactory long-lasting solution. Hyaluronic fillers are relatively easy to administer but are prone to migration and are temporary. Cannula-based orbital fat grafting has not gained the status of standard of care because of perceived low likelihood of success in the near term. This paper describes a technique for fat volume augmentation, its rationale, long-term follow-up, and a description of a complication unique to fat grafting in the orbit. METHODS: Ten consecutive subjects with acquired anophthalmic enophthalmos were enrolled in two IRB (institutional review board)-approved protocols (10.27 and 12.01) undergoing a single session of autologous fat grafting to the orbit using a closed blunt cannula technique. Preoperative photography and non-contrast MRIs (magnetic resonance imaging) were obtained prior, immediately after, and at 1 year after injection. Yearly postoperative photography was performed on subjects with successful results. RESULTS: Three of five subjects in IRB 10.27 clearly showed a clinically apparent increase in orbital volume at 1 year. One subject who failed to show improvement also sustained inadvertent injection into three extraocular muscles; she subsequently volunteered to enter IRB 12.01. Three of five subjects in IRB 12.01 did benefit, showing volume increase at 1 year, including the subject who had experienced intramuscular injection in 10.27. One subject in IRB 12.01 was lost to follow-up. Of the total of ten subjects enrolled, three showed no improvement and one was lost to follow-up; six subjects showed volume improvement at 1 year with two retaining the correction at 5 years and four showing variable diminution over 2-5 years. With the exception of the subject who sustained injection into extraocular muscles, none experienced complications. CONCLUSION: A modified technique is recommended for orbital fat injection distinct from methods used elsewhere in the body. Theoretical limits of volumetric enhancement temper expectations in orbital fat grafting and should inform surgical planning. Cannula-based orbital fat grafting can be done safely and result in a gain of orbital fat volume at 1 year and in some cases up to 5 years. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Extraocular Pressure Measurements to Avoid Orbital Compartment Syndrome in Aneurysm Surgery.

BACKGROUND: Orbital compartment syndrome (OCS) is a rare but devastating complication following pterional craniotomy. Although the causes of OCS are unclear, external compression of the orbit by a myocutaneous flap is commonly mentioned as a major factor. We evaluated the ocular influence of external compression using an extraocular pressure monitor. METHODS: We measured extraocular pressure in 86 patients who underwent surgery for cerebral aneurysm via a pterional approach. Clinical information and radiologic parameters, including the area of the medial rectus muscle (MRM) and the craniotomy height from the bottom of the anterior skull base, were collected. As a control group, 117 patients who underwent surgery without pressure monitoring were also evaluated. RESULTS: Extraocular pressure reached a maximum during craniotomy (mean, 22.0 mm Hg; range, 18.4-51.0 mm Hg) and decreased after myocutaneous flap adjustment (mean, 7.9 mm Hg; range, 5.4-17.5 mm Hg). Pressure before myocutaneous flap manipulation differed between patients with anterior communicating artery (Acomm) aneurysms and other patients (mean, 16.5 mm Hg vs. 9.4 mm Hg; P = 0.003). Among Acomm aneurysm cases, the monitored group showed a significantly lower MRM swelling ratio (postoperative MRM area/preoperative MRM area) compared with the control group (1.03 ± 0.10 vs. 1.17 ± 0.15; P = 0.036). CONCLUSIONS: Myocutaneous flaps can produce unnoticed overpressure on the orbit, resulting in OCS-related blindness during aneurysm clipping surgery, especially in cases involving mandatory lower craniotomy. The continuous extraocular compressive pressure monitoring technique is a simple and effective approach to prevent such a serious complication.

Conservatively Treated Orbital Blowout Fractures: Spontaneous Radiologic Improvement.

PURPOSE: To determine if conservatively treated blowout fractures of the orbit undergo spontaneous improvement based on radiologic findings. DESIGN: Prospective, noncomparative series. PARTICIPANTS: Patients with conservatively treated orbital blowout fractures in a single tertiary institution from 2012 through 2016 with initial and follow-up computed tomography (CT) scans. METHODS: Comparison of initial and follow-up CT to assess for smoothening of bony contour, joining of bony edges, reduction in herniation of orbital contents, and new bone formation. Orbital and fracture volumes were calculated using a 3-dimensional reconstruction software program (3D Workstation; TeraRecon, Foster City, CA). MAIN OUTCOME MEASURES: Change in bony contour, new bone formation, and decrease in orbital and fracture volumes. RESULTS: Our study comprised 41 patients and 44 orbits, with 38 unilateral and 3 bilateral cases. Most were men (65.9%; n = 27), and the mean age was 34.3±13.5 years. The mean time from injury to follow-up scan was 4.6 months (range, 1-15 months). All orbits showed changes in bony contour from initial to follow up CT, including smoothening of the orbital contour (88.6%), joining of bony edges (90.9%), and reduction in herniation of orbital contents (65.9%). Most of the orbits (n = 41; 93.2%) showed features of neobone formation. Of the 44 orbits, 91.4% showed a decrease in orbital volume, whereas 94.3% showed a decrease in fracture volume. The reduction in volume was statistically significant for both orbital (from 23.7±4.0 to 21.8±3.9 ml) as well as fracture (from 1.2±0.8 to 0.7±0.6 ml) volumes from initial to follow-up scans, respectively (P < 0.001). CONCLUSIONS: A large proportion of patients showed improvement in radiologic findings despite being treated conservatively. This highlights the spontaneous improvement that can occur in untreated blowout fractures not just clinically, but radiologically, in terms of soft tissue and bony findings.

Measurement of Orbital Biomechanical Properties in Patients with Thyroid Orbitopathy Using the Dynamic Scheimpflug Analyzer (Corvis ST).

PURPOSE: To investigate orbital biomechanical properties in patients with thyroid orbitopathy and in age- and gender-matched healthy subjects using the Corvis-ST (CST, Oculus Wetzlar, Germany). METHODS: The CST allows a non-contact tonometry with an ultra-high-speed Scheimpflug device to record the deformation of the cornea during an air pulse. Biomechanical response parameters (intraocular pressure (IOP), whole eye movement length (WEMl) and time (WEMt), deflection amplitude 2 mm ratio max, deflection amplitude max, stiffness parameter, and biomechanically corrected IOP were measured in 39 patients with thyroid orbitopathy (= group I) and in 33 age- and gender-matched healthy subjects (= group II) using the CST. RESULTS: Mean age in group I was 54.3 ± 11.6 years and in group II 54.2 ± 12.3 years with no statistical significant difference between the groups (P = 0.98). The gender distribution between the groups was not statistically significantly different (P = 0.51). Mean central corneal thickness was 571 ± 30 µm in group I and 563 ± 36 µm in group II (P = 0.306). There were statistically significant differences (P < 0.001) between groups I and II in mean IOP (19.3 ± 4.5 vs. 14.8 ± 2.3 mmHg, mean biomechanically corrected IOP (17.1 ± 3.4 vs. 13.4 ± 2.1 mmHg), mean WEMl (207 ± 57 vs. 322 ± 50 µm), mean WEMt (20.5 ± 1.0 vs. 21.9 ± 0.7 ms), mean IOP-adjusted WEMl (213 ± 56 vs. 314 ± 62 µm), and in mean stiffness parameter (132.5 ± 29.6 vs. 107.8 ± 23.3 mmHg/mm), respectively. CONCLUSION: Biomechanical parameters as measured by the CST were significantly reduced in patients with thyroid orbitopathy compared to age- and gender-matched healthy subjects, indicating a reduction in orbital compliance in thyroid orbitopathy. The parameters WEMl and WEMt might be a useful diagnostic tool to evaluate the condition of the eyeball within the orbit.

Bilateral Subperiosteal Hematoma and Orbital Compression Syndrome in Sickle Cell Disease.

A 14-year-old boy with sickle cell disease presented with preseptal cellulitis findings as proptosis, eyelid edema, and hyperemia. His best corrected visual acuity in the right eye was 20/20 and 16/20 in the left eye. He had limited ductions in vertical and lateral gazes in both eyes. Bilateral venous tortuosity was observed in posterior segment examination. Orbital bone infarction and subperiosteal hematoma were seen in magnetic resonance imaging. He was diagnosed as having orbital compression syndrome secondary to vaso-occlusive crisis of sickle cell disease and was treated with intravenous ampicilin-sulbactam and methylprednisolone.

Biomechanic Factors Associated With Orbital Floor Fractures.

IMPORTANCE: Orbital floor fractures are commonly seen in clinical practice, yet the etiology underlying the mechanism of fracture is not well understood. Current research focuses on the buckling theory and hydraulic theory, which implicate trauma to the orbital rim and the globe, respectively. OBJECTIVE: To elucidate and define the biomechanical factors involved in an orbital floor fracture. DESIGN, SETTING, AND PARTICIPANTS: A total of 10 orbits from 5 heads (3 male and 2 female) were used for this study. These came from fresh, unfixed human postmortem cadavers that were each selected so that the cause of death did not interfere with the integrity of orbital walls. Using a drop tower with an accelerometer, we measured impact force on the globe and rim of cadaver heads affixed with strain gauges. RESULTS: The mean impacts for rim and globe trauma were 3.9 J (95% CI, 3.4-4.3 J) and 3.9 J (95% CI, 3.5-4.3 J), respectively. Despite similar impact forces to the globe and rim, strain-gauge data displayed greater mean strain for globe impact (6563 µS) compared with rim impact (3530 µS); however, these data were not statistically significant (95% CI, 3598-8953 µS; P = .94). CONCLUSIONS AND RELEVANCE: Our results suggest that trauma directly to the globe predisposes a patient to a more posterior fracture while trauma to the rim demonstrates an anterior predilection. Both the hydraulic and buckling mechanisms of fracture exist and demonstrate similar fracture thresholds. LEVEL OF EVIDENCE: NA.

Ophthalmic Changes Associated with Long-Term Exposure to Microgravity.

This review discusses recent publications on the problem of ophthalmic changes associated with long-term effects of microgravity during space flights. Described changes include hyperopic shift of refraction, change in intraocular pressure, increased intracranial pressure, changes in the choroid and retina tissues, and swelling of the optic nerve. These effects are caused by redistribution of blood and fluid to the upper half of the body, increased intracranial pressure and congestion of venous blood and lymph in the upper half of the body and head. The reviewed also discusses other factors that may triggervision impairment caused by microgravity. Photographic illustrations of changes are also provided.

[Biomechanics analysis of the impact of maxillofacial injury on skull base damage].

OBJECTIVE: To analyze the impact of maxillofacial injury on skull base. METHODS: A three-dimensional(3D)finite-element model of cranio-maxillofacial bone was established by CT scan data. A lead cylinder in base diameter of 3 cm was designed as an impactor. There regions(upper right maxilla, left infraorbital margin and left zygomatic body)subjected to an impact at the speed of 8.6 m/s(about 30 km/h)was simulated. Thirteen landmarks at the skull base were selected. The values of stress at the end of 0.5, 1.0, 1.5, 2.0 ms were obtained, and the results were analyzed. RESULTS: The dynamic process of the fracture of the jaw and the stress distribution and conduction of the skull base were successfully simulated in three parts of the face. When the impact was on the right maxillary bone region, the stress values of the three points(medial foramen rotundum, medial foramen rotundum, anterior clivus reached the peak at each time point, 26.2, 22.4, 21.5 MPa(t=0.5 ms)and 70.0, 55.0, 45.0 MPa(t=1.0 ms)and 38.0, 26.5, 39.5 MPa(t=1.5 ms)and 26.0, 19.0, 23.0 MPa(t=2.0 ms), respectively. When the impact was on the left margo infraorbitalis orbitaeta region, the stress values of the two points(medial left foramen rotundum, posterior clivus)reached the peak at each time point, 8.8, 16.0 MPa(t=0.5 ms)and 10.0, 18.0 MPa(t=1.0 ms)and 5.5, 6.0 MPa(t=1.5 ms)and 11.5, 12.5 MPa(t=2.0 ms), respectively. When the impact was on the body of left zygomatic bone, the stress values of posterior clivus were 45.0 MPa(t=0.5 ms), 40.0 MPa(t=1.0 ms), 12.0 MPa(t=1.5 ms), 42.5 MPa(t= 2.0 ms), respectively. CONCLUSIONS: According to the difference of stress distribution and conduction of maxillofacial and skull base bone, the speed and the path of force transfer to the skull base were different. Finite-element dynamic simulation can be used for the biomechanics research on maxillofacial trauma.