OBJECTIVE: With the improvement of surgical techniques, instruments and diagnostic imaging, the aneurysmal surgery could be performed less invasively with less retraction of neural structure and more smaller craniotomy. The authors present a superior orbital rim approach as minimally invasive anterior circulation aneurysm surgery. METHODS: Superior orbital rim approach was performed for the treatment of the anterior circulation aneurysms with or without clinoidectomy. We considered the indications and limitations of this approach and compared this approach with conventional approaches. RESULTS: The operative technique can be used in all cases of anterior circulation aneurysms and could give us excellent results, especially, in internal carotid artery aneurysms. In cases of middle cerebral artery aneurysms, more wide and lateral approaches were used. In general, operation time was shortened and transfusion was not needed. CONCLUSION: The superior orbital rim approach is a good alternative procedure to conventional microsurgical approach in treating anterior circulation aneurysms.
Aneurysm* ; Carotid Artery, Internal ; Craniotomy ; Diagnostic Imaging ; Intracranial Aneurysm ; Orbit*

Child ; Edema ; diagnostic imaging ; etiology ; Emphysema ; diagnostic imaging ; etiology ; Ethmoid Bone ; diagnostic imaging ; injuries ; Eyelid Diseases ; diagnostic imaging ; etiology ; Humans ; Male ; Orbit ; diagnostic imaging ; Orbital Diseases ; diagnosis ; diagnostic imaging ; pathology ; Radiography ; Skull ; diagnostic imaging ; pathology ; Skull Fractures ; complications ; diagnostic imaging

OBJECTIVE: To show imaging findings of inferior orbital fissure (IOF) and groove (IOG) on axial CT scans and to discover their anatomic variations, so as to avoid misdiagnosing them as orbital fracture. METHODS: 25 normal skull were used to investigate the configurations of IOF and IOG. Five skulls were performed axial CT scans. 20 normal orbital axial scans were studied as well. MPR and RT-3D reconstructions were used in this study. RESULTS: Skulls scans and normal orbital images on axial CT showed three sorts of findings: (1) single bony dehiscence between lateral and inferior walls; (2) first type of double bony dehiscence between lateral and inferior walls, among the dehiscence interposing a small bone. The long axis of the small bone was parallel to orbital wall; (3) second type of double bony dehiscence between lateral and inferior walls, but the long axis of the small bone was in anteroposterior direction. Anatomy and variation of three sorts of CT findings were corresponded respectively to: (1) a baseball club-shaped IOF; (2) a "V"-shaped IOF, that is composed of both of lateral and internal ramus, lateral ramus situates between the zygoma and the lateral portion of greater wing of sphenoid, and internal ramus between the maxilla and the internal portion of greater wing of sphenoid, both rami intercross caudally and open upwards in a "V"-shaped configuration; (3) a deep IOG with a protuberant lateral wall. CONCLUSION Familiarity of imaging features on the axial CT scans and understanding of their anatomy of IOF and IOG would be helpful for avoiding misdiagnosis of orbital fracture.
Cadaver ; Forensic Medicine ; Humans ; Imaging, Three-Dimensional ; Orbit/diagnostic imaging* ; Orbital Fractures/pathology* ; Skull/diagnostic imaging* ; Sphenoid Bone/diagnostic imaging* ; Tomography, X-Ray Computed/methods*

OBJECTIVETo understand the anatomy of the supraorbital ethmoid cell and its relationship with the frontal sinus drainage pathway.

METHODSFive patients (5 sides) who had supraorbital ethmoid cell underwent endoscopic frontal sinus surgery. Computed tomographic (CT) scans of the sinuses were obtained in coronal and axial views. The frontal sinus ostium and the supraorbital ethmoid cell were endoscopically identified respectively.

RESULTSOn coronal CT scans, the supraorbital ethmoid cell was a separate cell lateral to the frontal sinus. And on axial CT scans, it was lateral and posterior to the frontal sinus drainage pathway. Under endoscope, its opening was lateral and posterior to the frontal sinus ostium.

CONCLUSIONSThe supraorbital ethmoid cell extended superolateral the boundaries of the lamina papyracea and the roof of the ethmoid to pneumatize the orbital plate of the frontal bone.

Adult ; Endoscopy ; Female ; Frontal Sinus ; anatomy & histology ; diagnostic imaging ; Humans ; Male ; Orbit ; anatomy & histology ; diagnostic imaging ; Tomography, X-Ray Computed

OBJECTIVETo evaluate the accuracy of measurement of the globe proptosis by CT in patients with unilateral orbital fracture.

METHODS25 patients with unilateral orbital fracture were included. CT was performed before and after operation. The globe proptosis on the unaffected side was measured before and after operation by using Hertel exophthalmometer (HE), CT images with orbital lateral rim (OLR) and the optic nerve foramen (ONF) as reference points. The accuracy was evaluated comparably by statistical analyses.

RESULTSThe preoperative and postoperative average globe proptosis were (13.9 +/- 3.1) mm and (12.5 +/- 2.2) mm in HE group, (16.1 +/- 2.6) mm and (15.7 +/- 2.3) mm in the OLR group, (45.3 +/- 4.8) mm and (46 +/- 3.9) mm in the ONF group, showing a significant difference between the pre-and post-operative results in HE group, but not in OLR and ONF groups.

CONCLUSIONSCT measurement with the orbital lateral rim as reference point is more reliable than Hertel exophthalmometer measurement for globe proptosis.

Adolescent ; Adult ; Exophthalmos ; diagnostic imaging ; Humans ; Middle Aged ; Orbit ; diagnostic imaging ; Orbital Fractures ; diagnostic imaging ; Tomography, X-Ray Computed ; methods ; Young Adult

Computer-assisted medical imaging has shown tremendous improvements in definition of in vivo anatomy of patients with craniofacial anomalies. In accordance with developments of simulation surgery, preoperative surgical simulation can now be performed more accurately and interactively within the environment of computer graphic workstation and can also provide the best solution for surgery by displaying the 3 dimensional simulation images. The interactive surgical simulation approach is based on digitally osteotomized objects which have been translocated manually by an operator who visually determines the amount of movement required until the desired end result is achieved. However, this approach depends upon subjective assessment and may not consistently provide optimal simulation in all directions due to manual movement of the osteotomized object by mouse or trackball. In addition, this procedure is time and labor intensive due to repetitive processing to obtain a satisfactory end result. This study demonstrates a method of surface matching of digitally osteotomized objects, by simulating the deformed orbit to the assumed ideal position of mirror image without manual manipulation of simulation objects. This process can move the osteotomized object to the preset end results-mirror image- automatically by computer module. The single processing of the osteotomized segment changes the position of simulated segments with certainty. This procedure allows more accurate and reliable result of simulation surgery. However, it will be valuable only when one can determine the ideal end results such as mirror image of this article as a normal template.
Animals ; Automation ; Computer Graphics ; Diagnostic Imaging ; Goldenhar Syndrome ; Humans ; Mice ; Orbit*

Adult ; Head Injuries, Penetrating ; diagnostic imaging ; etiology ; surgery ; Humans ; Male ; Orbit ; injuries ; Tomography, X-Ray Computed

OBJECTIVETo fabricate a rapid prototyping (RP) 3-D image models for individual reconstruction of orbital bony loss.

METHODSThe skull was placed on a helical CT scanner table and the Frankfort plane was perpendicular to the table. The CT data was obtained by a Aquilion (TOSHIBA, Japan) with 1 mm thickness section in spiral mode. By adjusting of CT threshold value and pixels in order to stack the segmental defects, we obtained an approximate 3-dimension visual model of the scanned skull using MedGraphics software. An orbital RP model based on the dataset of the 3-dimension visual model was fabricated by RP machine. Both 3-dimension visual model and RP model were measured against the skull with several anatomic landmarks to examine the accuracy of the models, and the errors were analysed.

RESULTSIntegrity precision rapid RP models of the orbital region were reconstructed. The anterior orbital rim, middle orbital section and posterior orbital section were all fabricated. Optic foramen, superior orbital fissure, infraorbital foramen, inferior orbital fissure, lacrimal sac socket and naso-lacrimal duct were shown clearly. But some fine hole and slot, such as the anterior ethmoidal foramen, posterior ethmoidal foramen and zygomaticofrontal suture were not obviously seen. The mean difference between the 3-dimension visual model and the skull was 0.10 +/- 1.02mm. For the RP and dry skull, the mean difference was 0.22 +/- 1.04mm. There were no statistical differences between them.

CONCLUSIONSIntegrity precision orbital RP models were fabricated which fulfilled the requirements of the individual reconstruction with bony orbital pathologic changes. The keys to fabricate the precision orbital RP models included a closer cooperation between the surgeon and engineer, thin CT slice in 1mm thick and an appropriated threshold value. Better results for the orbital deformities should be achieved for the contour of orbital region or eye function.

Humans ; Image Processing, Computer-Assisted ; methods ; Models, Anatomic ; Orbit ; anatomy & histology ; diagnostic imaging ; Radiography

Bone Cysts, Aneurysmal ; diagnosis ; diagnostic imaging ; Female ; Humans ; Middle Aged ; Orbit ; Tomography, X-Ray Computed

OBJECTIVETo evaluate the 3-D position changes of periorbital structures after midface distraction osteogenesis in patients with Crouzon syndrome.

METHODSThe CT data of 8 cases who had accepted the midface distraction osteogenesis following Le Fort III osteotomy were retrospectively analyzed. The patients were averagely 11.9 years old, and the CT was performed before and one year after operation. After 3-D image reconstruction, a right-hand coordinate system based on the preoperational Frankfurt Plane was then established. The pre- and post-operative positions of the superior orbit point (SOr), inferior orbit point (IOr), median orbit point (MOr), lateral orbit point (LOr), anterior ocularis point (AO), ocularis eyeball point (PO) and the four insertion ocularis rectus were documented and compared. The positions of these marked points in normal controls were also documented and compared with those in patients.

RESULTSAfter midface distraction osteogenesis, the position of AO was not changed significantly on the y-axis and z-axis, but the distance between two AO points on x-axis was reduced by 3.40 mm; IOr moved averagely 12.24 mm on y-axis and 4.25 mm on z-axis, MOr moved averagely 10.11 mm on y-axis and 2.80 mm on z-axis, LOr moved averagely 9.86 mm on y-axis and 2.31 mm on z-axis. The Inferior Rectus attachment moved averagely 3.63 mm on y-axis and 2.98 mm on z-axis. No other significant change was observed on other marked points.

CONCLUSIONSMidface distraction osteogenesis following Le Fort III osteotomy can significantly move the medial, lateral and inferior peri-orbital bone structure anteriorly and inferiorly. The eyeballs have no markedly sagittal position changes after distraction except slight medial, downwards movements and anterior-upwards rotations.

Adolescent ; Child ; Facial Bones ; diagnostic imaging ; surgery ; Female ; Humans ; Imaging, Three-Dimensional ; Male ; Orbit ; diagnostic imaging ; Osteogenesis, Distraction ; methods ; Osteotomy, Le Fort ; methods ; Tomography, X-Ray Computed