We report two cases of supratentorial gangliocytomas mimicking an extra-axial tumor. MR imaging indicated that the tumors were extra-axial, and meningiomas were thus initially diagnosed. Relative to gray matter, the tumors were hypointense on T1-weighted images and hyperintense on T2-weighted images. On contrast-enhanced T1-weighted images, homogeneous enhancement was observed, while CT scanning revealed calcification in one of the two cases.
Adult ; Brain Neoplasms/*diagnosis/pathology ; Case Report ; Female ; Ganglioneuroma/*diagnosis/pathology ; Human ; *Magnetic Resonance Imaging ; Middle Age

Neurenteric cyst is very rare congenital disease and usually presents symptoms in adulthood. It can cause major neurological deficits if detection and treatment are delayed. It is also known to be a source of serious infection of the central nervous system. Neurenteric cyst is usually located in the ventral aspect of the lower cervical or upper thoracic spinal cord. Intracranial neurenteric cyst is very uncommon and less than 35 cases have been reported in the literature. We report MRI findings of two cases of intracranial neurenteric cyst and review the literature.
Central Nervous System ; Magnetic Resonance Imaging* ; Neural Tube Defects* ; Spinal Cord

PURPOSE: A compression plate fixation was generally used in the fracture of a femoral diaphysis but it produced the stress shielding problem which resulted in a decrease of bone mass and impaired mechanical properties. This study was designed to compare with the stiffnesses of three different internal fixation types ; fixation with only plate, with only cross-pins, and with both a plate and cross-pins. MATERIALS AND METHODS: To compare the stress distribution and stiffness of three types of fixation devices, the device-bone system are analyzed under axial compression(70Kg) and 3-point bending(500Nmm) in planes using the 2-D finite element method(ABAQUS 5.8). Also the stiffness of each device was evaluated at seven different time points during fracture healing by increasing Young's modulus of callus. RESULTS: The plate fixation model had the highest stress distribution and occurred the stress concentration in the cortex beneath the plate. During the healing of bone fracture, the fixation with cross-pins relatively had a higher compression and bending stiffness. The fixation with only cross-pins was as stiff as that with an only plate in bending but less stiff than in compression. CONCLUSION: The internal fixation added to cross-pins may decrease the stress shielding problems due to dispersing the stress concentration and also improve the stiffness of a device-bone system.
Bony Callus ; Diaphyses ; Elastic Modulus ; Finite Element Analysis ; Fracture Healing ; Fractures, Bone

OBJECTIVES: This study sought to compare efficiency results between the use of a customized implant (CI) and a reconstruction plate (RP) in mandibular defect reconstruction in an animal model. MATERIALS AND METHODS: Fifteen rabbits underwent surgery to create a defect in the right side of the mandible and were randomly divided into two groups. For reconstruction of the mandibular defect, the RP group (n=5) received five-hole mini-plates without bone grafting and the CI group (n=10) received fabricated CIs based on the cone-beam computed tomography (CBCT) data taken preoperatively. The CI group was further divided into two subgroups depending on the time of CBCT performance preoperatively, as follows: a six-week CI (6WCI) group (n=5) and a one-week CI (1WCI) group (n=5). Daily food intake amount (DFIA) was measured to assess the recovery rate. Radiographic images were acquired to evaluate screw quantity. CBCT and histological examination were performed in the CI subgroup after sacrifice. RESULTS: The 1WCI group showed the highest value in peak average recovery rate and the fastest average recovery rate. In terms of reaching a 50% recovery rate, the 1WCI group required the least number of days as compared with the other groups (2.6±1.3 days), while the RP group required the least number of days to reach an 80% recovery rate (7.8±2.2 days). The 1WCI group showed the highest percentage of intact screws (94.3%). New bone formation was observed in the CI group during histological examination. CONCLUSION: Rabbits with mandibular defects treated with CI showed higher and faster recovery rates and more favorable screw status as compared with those treated with a five-hole mini-plate without bone graft.
Bone Transplantation ; Cone-Beam Computed Tomography ; Eating ; Mandible ; Mandibular Reconstruction ; Models, Animal ; Osteogenesis ; Printing, Three-Dimensional ; Rabbits ; Transplants

OBJECTIVES: This study sought to compare efficiency results between the use of a customized implant (CI) and a reconstruction plate (RP) in mandibular defect reconstruction in an animal model. MATERIALS AND METHODS: Fifteen rabbits underwent surgery to create a defect in the right side of the mandible and were randomly divided into two groups. For reconstruction of the mandibular defect, the RP group (n=5) received five-hole mini-plates without bone grafting and the CI group (n=10) received fabricated CIs based on the cone-beam computed tomography (CBCT) data taken preoperatively. The CI group was further divided into two subgroups depending on the time of CBCT performance preoperatively, as follows: a six-week CI (6WCI) group (n=5) and a one-week CI (1WCI) group (n=5). Daily food intake amount (DFIA) was measured to assess the recovery rate. Radiographic images were acquired to evaluate screw quantity. CBCT and histological examination were performed in the CI subgroup after sacrifice. RESULTS: The 1WCI group showed the highest value in peak average recovery rate and the fastest average recovery rate. In terms of reaching a 50% recovery rate, the 1WCI group required the least number of days as compared with the other groups (2.6±1.3 days), while the RP group required the least number of days to reach an 80% recovery rate (7.8±2.2 days). The 1WCI group showed the highest percentage of intact screws (94.3%). New bone formation was observed in the CI group during histological examination. CONCLUSION Rabbits with mandibular defects treated with CI showed higher and faster recovery rates and more favorable screw status as compared with those treated with a five-hole mini-plate without bone graft.

BACKGROUND: Fine needle aspiration (FNA) is regarded as initial diagnostic procedure for thyroid nodules due to its accuracy and safety. One of the limitations of FNA is variable rate of inadequate specimen. Recently, ultrasound guidance has been suggested as a valuable method to improve diagnostic performance of FNA. The aim of this study is to evaluate the rates of adequate specimen when FNA is done with ultrasound guidance. METHODS: This study was performed on 304 patients who underwent ultrasound-guided FNA for thyroid nodules. Ultrasound-guided FNA was performed due to various causes. RESULTS: Inadequate specimens were obtained from 62 patients (20.4%). The sizes of thyroid nodules from which specimen obtained were 1.63+/-1.17 cm for adequate specimen, 1.18+/-0.72 cm for inadequate specimen respectively and differed significantly (p=0.001). When patients were divided by the size of thyroid nodules, the rates of inadequate specimen were significantly different between the groups above 1.5 cm and less than 1.5 cm (p=0.04). The rates of inadequate specimen were also different according to the indications of ultrasound guidance, 25.4% in nonpalpable thyroid nodules and 11.4% in complex cysts. When complex cyst group was divided by the size of thyroid nodules, the rates of inadequate specimen were not different. CONCLUSION: There are less benefits of ultrasound-guided FNA for patients with nodule size less than 1.5 cm. We recommend ultrasound guidance for patients with complex cyst rather than nonpalpable thyroid nodules.
Biopsy, Fine-Needle* ; Humans ; Thyroid Gland* ; Thyroid Nodule* ; Ultrasonography

PURPOSE: Coiling or infusion of embolic materials into a wide necked aneurysm can be performed with stenting. The purpose of our study is to assess the technical feasibility of aneurysm treatment with glue embolization after stenting. MATERIALS AND METHODS: We used four Wallstents for surgically repairing eight canine carotid aneurysms. After confirmation of the aneurysms on the angiogram, we introduced a 6-7 F guiding catheter in order to deploy the stents. After stenting, we passed a microcatheter into the aneurysm lumen through the stent mesh. 28% glue was slowly injected until the glue cast completely filled the lumen. We evaluated the passage of a microcatheter through the stent meshwork, formation of the glue cast and the stents' ability to protection for any leakage of glue. The follow-up angiogram was obtained for two dogs, one to three times until 8 weeks, and then we sacrificed the dogs and performed pathologic examinations. RESULTS: Stenting was successful in all cases except one in which the vessel was occluded because the stent was not completely expanded within the lumen. The microcatheter could not pass through the stent mesh in one aneurysm. The two week follow-up angiogram showed complete occlusion of the aneurysm and a patent carotid lumen in a case after successful stenting and glue embolization without distal migration of glue. Tungsten in the glue was noted to migrate out of aneurysm into the soft tissue of the neck. Histopathologic examination showed successful obliteration and stable organization of the aneurysmal lumen with ingrowth of fibroblasts and a foreign body reaction. In contrast, the aneurysms without the glue embolization being performed showed partially thrombosed aneurysmal lumens that became smaller and indistinct on the 8 week follow-up angiograms. Histopathologic examination showed a disorganized thrombus with numerous recanalizations. CONCLUSION: Glue embolization after stenting could be performed for aneurysm without distal migration of the glue or gluing of the catheter. This concept appears to be useful for applications to the further research and the treatment of aneurysm.
Adhesives* ; Aneurysm* ; Animals ; Carotid Arteries* ; Catheters ; Dogs ; Fibroblasts ; Follow-Up Studies ; Foreign-Body Reaction ; Intracranial Aneurysm ; Neck ; Stents* ; Thrombosis ; Tungsten

We report a case of ganglioneurocytoma manifesting as a complex partial seizure in a young adult male. MR images depicted a well-marginated cystic mass with a heterogeneous solid portion abutting the dura in the parietal lobe. The solid portion showed minimal heterogeneous enhancement, and pressure erosion of the overlying calvarium had occurred. Following gross total resection, the clinical outcome was satisfactory, with no further seizures, and during the five-year follow-up period, the tumor did not recur.
Adult ; Brain Neoplasms/*pathology ; Case Report ; Follow-Up Studies ; Ganglioneuroma/*pathology ; Human ; Magnetic Resonance Imaging ; Male ; Neurocytoma/*pathology ; Parietal Lobe/*pathology

PURPOSE: To evaluate the MR findings of optic chiasmatic glioma (OCG). MATERIALS AND METHODS: MR images were reviewed in 14 patients with histologically proven OCGs and one with neurofibromatosis type 1 (male: female=8:7, mean age=8.5 years). Tumors were evaluated retrospectively with respect to their size, involvement of the optic pathway, transverse/vertical diameter ratio based on the coronal plane, signal intensities, enhancement pattern, and the presence of a cyst or calcification. RESULTS: Tumors was measured 1.7-5.5 (mean, 3.3) cm in maximum diameter. In ten patients, the optic tracts were involved, and in three, the optic nerves. In 12 patients, tumors had a transverse/vertical diameter ratio of over one, and showed iso (n=5) or low signal intensity (n= 10) compared with gray matter at T1-weighted imaging and high signal intensity (n=15) at T2-weighted imaging. Cyst formations were seen in eight patients, and tumors were enhanced strongly and homogeneously in nine and peripherally in four. In seven there was associated hydrocephalus, and in one, calcification. CONCLUSION: OCG is a suprasellar tumor which can extend into the optic pathway, has a transverse/vertical diameter ratio of more than one, and shows strong and homogeneous enhancement. These MR imaging findings are useful for the differentiation of OCG from other suprasellar tumors.
Glioma* ; Humans ; Hydrocephalus ; Magnetic Resonance Imaging* ; Neurofibromatosis 1 ; Optic Nerve ; Retrospective Studies ; Visual Pathways