• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.18 no.4
• /
• pp.741-745
• /
• 1996

AVMs is not a neoplasm, but a congenital developmental anomalies.$^{5)}$ In oral and maxillofacial area, the high recurrence rate and more facial disfigurement give a difficult problem to surgen and patient.$^{8)}$ Conventional treatment modality nowadays is presurgical embolization and surgical resection. In treatment planning, we consider the possibility of complete surgical resection and the esthetics of soft tissue reconstruction. But, two things are very difficult to achieve. We present a patient with AVMs in left upper lip, he had presurgical embolization with Ivalon and Bucrylate, and conservative surgical procedure. So we present this possible treatment modality.

• Archives of Reconstructive Microsurgery
• /
• v.24 no.2
• /
• pp.41-49
• /
• 2015

Free or pedicled vascularized fibular grafts (VFG) are useful for the reconstruction of large skeletal defects, particularly in cases of scarred or avascular beds, or in patients with combined bone and soft tissue defects. Compared to non-VFG, VEG, which contains living osteocytes and osteoblasts, maintains its own viability and serves as good osteoconductive and osteoinductive graft. Due to its many structural and biological advantages, the free fibular osteo- or osteocutaneous graft is considered the most suitable autograft for the reconstruction of long bone defects in the injured extremity. The traditional indication of VFG is the long bone and soft tissue defect, which cannot be reconstructed using a conventional operative method. Recently, the indications have been widely expanded not only for defects of midtibia, humerus, forearm, distal femur, and proximal tibia, but also for the arthrodesis of shoulder and knee joints. Because of its potential to allow further bone growth, free fibular epiphyseal transfer can be used for the hip or for distal radius defects caused by the radical resection of a tumor. The basic anatomy and surgical techniques for harvesting the VFG are well known; however, the condition of the recipient site is different in each case. Therefore, careful preoperative surgical planning should be customized in every patient. In this review, recently expanded surgical indications of VFG and surgical tips based on the author's experiences in the issues of fixation method, one or two staged reconstruction, size mismatching, overcoming the stress fracture, and arthrodesis of shoulder and knee joint using VFG are discussed with the review of literature.

• Journal of Korean Neurosurgical Society
• /
• v.59 no.4
• /
• pp.405-409
• /
• 2016

Meningiomas are typically diagnosed by their characteristic appearance on conventional magnetic resonance imaging (MRI). However, detailed image findings regarding peri- and intra-tumoral anatomical structures, tumor consistency and vascularity are very important in pre-surgical planning and surgical outcomes. At the 7.0 T MRI achieving ultra-high resolution, it could be possible to obtain more useful information in surgical strategy. Four patients who were radiologically diagnosed with intracranial meningioma in 1.5 T MRI underwent a 7.0 T MRI. Three of them underwent surgery afterwards, and one received gamma knife radiosurgery. In our study, the advantages of 7.0 T MRI over 1.5 T MRI were a more detailed depiction of the peri- and intra-tumoral vasculature and a clear delineation of tumor-brain interface. In the safety issues, all patients received 7.0 T MRI without any adverse event. One disadvantage of 7.0 T MRI was the reduced image quality of skull base lesions. 7.0 T MRI in patients with meningiomas could provide useful information in surgical strategy, such as the peri-tumoral vasculature and the tumor-brain interface.

• Journal of Korean Neurosurgical Society
• /
• v.29 no.3
• /
• pp.345-352
• /
• 2000

Objective : The purpose of this study was to compare computed tomographic angiography(CTA) with conventional cerebral angiography(CCA) and to assess usefulness of CTA in detection and anatomic definition of intracranial aneurysms of the circle of Willis in subarachnoid hemorrhage. Patients and Methods : Fifty consecutive patients with known or suspected intracranial saccular aneurysms underwent CTA with preoperative CCA from 1997 to 1999. Using surface shaded display post-processing technique, CTA was interpreted for the presence, location of aneurysms and anatomic features. The image obtained with CTA was then compared with CCA image. Results : In 47 patients, CCA revealed 57 cerebral aneurysms and CTA revealed 54 aneurysms. Two of the 57 cerebral aneurysms were located outside of the imaging volume of CTA and one case was misdiagnosed. The sensitivity of CTA was 94.7% and the specificity was 100%. The results obtained with CTA were, compared with the results obtained with CCA, equal in determining dome shape, direction and lobularity. However, CTA provided a 3-dimensional representation of aneurysmal lesion very useful for surgical planning. Moreover, CTA was useful for rapid and relatively noninvasive detection of aneurysms in the circle of Willis. Conclusion : CTA can be a diagnostic tool for the patients with acute subarachnoid hemorrhage due to a ruptured aneurysm of the circle of Willis and provides adequate anatomic detail for surgical planning, especially to complex cerebral aneurysms. However, we think CCA is necessary because of CTA limitations including its difficulty in detecting unusually located aneurysms(including those in cavernous sinus or distal artery) and combined vascular lesion (including arteriovenous malformation) and acquiring dynamic flow information.

• Korean Journal of Computational Design and Engineering
• /
• v.16 no.5
• /
• pp.331-343
• /
• 2011

High tibial osteotomy (HTO) is a widely accepted treatment for unicompartmental osteoarthritis of the knee and other lower extremity deformities, particularly for young and active patients. However, it is generally recognized as a technically demanding procedure. Thus the limitations of conventional surgical methods have been reported. Currently, the use of computer-aided surgery (CAS) system for successful surgery was increased. However it has been reported many problems such as expensive equipment, infection or fracture caused by inserting half-pin and delaying surgery. Therefore we propose a novel method which can be tracked by using tracking-pin inserted in arbitrary locations of the femur and tibia, and fluoroscopic images obtained from G-arm of antero-posterior and lateral-medial.

• The Journal of the Korea Contents Association
• /
• v.14 no.11
• /
• pp.370-377
• /
• 2014

At present trend 3D Printing technology has been using more efficiently than conventional subtractive manufacturing method in various medical fields, in particular this technology superior in saving production time, cost and process than conventional. Especially in orthopedics, an attractive attention has been paid by adopting this technology because of improving operation, operation accuracy, and reducing the patient's pain. Though 3D printing technology has enormous applications still in some hospitals have not been using due to having the problem of technical utilization of hardware, software & chiefly financial availability and etc. In order to solve these problems by reducing the cost and time, we have used CT images in pre-operative planning by directly making the pelvic fracture model with open source DICOM viewer and STL file conversion program, assembly 3D printer of FDM wire additive manufacturing. After having the customized bone model of six patients who underwent unstable pelvic fracture surgery, we have operated our system in orthopedic section of University Hospital through the clinician. Later, we have received better reviews and comments on utilization availability, results, and precision and now our system considered to be useful in surgical planning.

• Journal of Korean Neurosurgical Society
• /
• v.29 no.2
• /
• pp.222-230
• /
• 2000

Purpose : Resection of the epileptogenic zone in the parietal and occipital lobes may be relevant although only few studies have been reported. Methods : Eight patients with parietal epilepsy and nine patients with occipital epilepsy were included for this study. Preoperatively, all had video-EEG monitoring with extracranial electrodes, MRI, 3D-surface rendering of MRI using Allegro(ISG Technologies Inc., Toronto, Canada), and PET scans. Sixteen patients underwent invasive recording with subdural grid. Eight had parietal resection including the sensory cortex in two. Seven had partial occipital resection. Two underwent total unilateral occipital lobectomy. The extent of the resection was made based mainly on the data of invasive EEG recordings, MRI, and 3D-surface rendering of MRI, not on the intraoperative electrocorticographic findings as usually done. During resection, electrocortical stimulation was performed on the motor cortex and speech area. Results : Out of eight patients with parietal epilepsy, three had sensory aura, two had gustatory aura, and two had visual aura. Six of nine patients with occipital epilepsy had visual auras. All had complex partial seizures with lateralizing signs in 15 patients. Four had quadrantopsia. One had mild right hemiparesis. Abnormality in MRI was noticed in six out of eight parietal epilepsy and in eight out of nine occipital epilepsy. 3D-surface rendering of MRI visualized volumetric abnormality with geometric spatial relationships adjacent to the normal brain, in all of parietal and occipital epilepsy. Surface EEG recording was not reliable in localizing the epileptogenic zone in any patient. The subdural grid electrodes can be implanted on the core of the structural abnormality in 3D-reconstructed brain. Ictal onset zone was localized accurately by subdural grid EEGs in 16 patients. Motor cortex in nine and sensory speech area in two were identified by electrocortical stimulation. Histopathologic findings revealed cortical dysplasia in 10 patients ; tuberous sclerosis was combined in two, hamartoma and ganglioglioma in one each, and subpial gliosis in six. Eleven patients were seizure free at follow-up of 6 months to 37 months(mean 19.7 months) after surgery. Seizures recurred in two and were unchanged in one. Six produced transient sensory loss and one developed hemiparesis and tactile agnosia. One revealed transient apraxia. Two patients with preoperative quadrantopsia developed homonymous hemianopsia. Conclusion : This study suggests that surgical treatment was relevant in parietal and occipital epilepsies with good surgical outcome, without significant neurologic sequelae. Neuroimaging studies including conventional MRI, 3Dsurface rendering of MRI were necessary in identifying the epileptogenic zone. In particular, 3D-surface rendering of MRI was very helpful in presuming the epileptogenic zone in patients with unidentifiable lesion in the conventional MRI, in planning surgical approach to lesions, and also in making a decision of the extent of the epileptogenic zone in patients with identifiable lesion in conventional MRI. Invasive EEG recording with the subdural grid electrodes helped to confirm a core of the epileptogenic zone which was revealed in 3D-surface rendered brain.

• Archives of Plastic Surgery
• /
• v.47 no.5
• /
• pp.428-434
• /
• 2020

Background Three-dimensional (3D) model printing improves visualization of anatomical structures in space compared to two-dimensional (2D) data and creates an exact model of the surgical site that can be used for reference during surgery. There is limited evidence on the effects of using 3D models in microsurgical reconstruction on improving clinical outcomes. Methods A retrospective review of patients undergoing reconstructive breast microsurgery procedures from 2017 to 2019 who received computed tomography angiography (CTA) scans only or with 3D models for preoperative surgical planning were performed. Preoperative decision-making to undergo a deep inferior epigastric perforator (DIEP) versus muscle-sparing transverse rectus abdominis myocutaneous (MS-TRAM) flap, as well as whether the decision changed during flap harvest and postoperative complications were tracked based on the preoperative imaging used. In addition, we describe three example cases showing direct application of 3D mold as an accurate model to guide intraoperative dissection in complex microsurgical reconstruction. Results Fifty-eight abdominal-based breast free-flaps performed using conventional CTA were compared with a matched cohort of 58 breast free-flaps performed with 3D model print. There was no flap loss in either group. There was a significant reduction in flap harvest time with use of 3D model (CTA vs. 3D, 117.7±14.2 minutes vs. 109.8±11.6 minutes; P=0.001). In addition, there was no change in preoperative decision on type of flap harvested in all cases in 3D print group (0%), compared with 24.1% change in conventional CTA group. Conclusions Use of 3D print model improves accuracy of preoperative planning and reduces flap harvest time with similar postoperative complications in complex microsurgical reconstruction.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.881-887
• /
• 2005

A total knee replacement is an extremely 'position-sensitive' operation; a malposition or a malalignment of the components will lead to a breakage of the component, a fracture around the knee prosthesis, and the limitation of range of the motion, etc. In a conventional total knee replacement, surgeons have to select an appropriate prosthesis according to the shape of the surgical region. A wrong selection may give rise to side effects or to need re-operation. Nevertheless, it is so difficult to choose the most proper prosthesis out of various kinds of prosthesis. This paper presents a surgical planning system for the total knee replacement with an operation simulating method in order to determine the parameters for the total knee replacement operation. We select an alignment axis and a resection angle as major operation parameters in the total knee replacement operation, and introduce the method to determine the major operation parameters with the operation simulator we developed. The simulator is used to determine operation parameters for optimized operations, to select the most appropriate prosthesis, and to analyze the prospective problems of the operation.

• Journal of Periodontal and Implant Science
• /
• v.38 no.4
• /
• pp.729-736
• /
• 2008

Purpose: Anterior ridge defect after tooth extraction results in unfavorable appearance. Ridge augmentation procedures should be preceded by careful surgical-prosthetic treatment planning, and various techniques can be used in anterior ridge augmentation. Materials and Methods: Three patients showed deformed ridges after tooth extraction. Three different techniques ; onlay-interpositional connective tissue graft; bovine hydroxyapatite graft with free connective tissue graft; bovine hydroxyapatite graft with resorbable collagen membrane following free connective tissue graft; were used for anterior ridge augmentation. Result: Soft tissue graft can be used in small amount of ridge defect, hard tissue graft combined with soft tissue graft can be used in large amount of ridge defect. After ridge augmentation, about three months of healing period, augmented tissue was stabilized. The final restoration was initiated after this healing period, and the tissue form was maintained stable. Conclusion: Careful diagnosis and surgical-prosthetic treatment planning with joint consultation prior to surgery should be performed in order to attain an optimal esthetic results.