• Investigative Magnetic Resonance Imaging
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• v.15 no.2
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• pp.170-175
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• 2011

Ancient schwannoma is a rare variant of schwannoma and a slow growing benign tumor associated with degeneration that may be diagnosed as a malignant tumor, because it presents with a large size and an inhomogeneous signal intensity. The main differential diagnosis of plexiform soft tissue tumor includes plexiform neurofibroma, malignant peripheral nerve sheath tumor (MPNST). In this case, we describe the MRI findings in a case of ancient schwannoma involving left thigh of a 63-year-old woman mimicking a plexiform MPNST. The tumor appeared as an inhomogeneous signal intensity and multinodular appearance, causing misdiagnosis as a plexiform MPNST.

• The Journal of the Korean bone and joint tumor society
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• v.11 no.1
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• pp.82-87
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• 2005

Both neurilemmoma and neurofibroma are originated from Schwann cell. Plexiform tumor was mostly neurofibroma but Neurilemmoma which has plexiform is extremely rare. So it is important to differentiate plexiform neurilemmoma from plexiform neurofibroma, because plexiform neurilemmoma appears to have neither a significant association with neurofibromatosis nor a propensity for malignant transformation. We report two cases of plexiform neurilemmoma involving the left arm and right foot.

• Journal of Chest Surgery
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• v.39 no.11 s.268
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• pp.875-878
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• 2006

A 39-year-old man presented with a esophageal submucosal tumor on regular check up examination. Preoperative exams showed the typical submucosal tumor as leiomyoma and operative procedure was enucleation for complete resection. Postoperative pathologic diagnosis including histologic and immunohistochemical study was compatible with plexiform schwannoma. Plexiform schwannoma is one of the least common variant of schwannoma that typically shows a plexiform or multinodular pattern. To our knowledge, there is rare case report of plexiform schwannoma originating in the esophagus and we report ore case with related literature.

• Journal of the Korean Orthopaedic Association
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• v.54 no.1
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• pp.84-89
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• 2019

Schwannomas are benign neoplasms with a Schwann cell origin. A plexiform schwannoma is a rare variant of a schwannoma with a plexiform or multinodular growth pattern. The condition occurs mostly as a solitary lesion in the skin or subcutaneous tissue, or uncommonly located in the deep soft tissue. We report a rare case of recurred multiple plexiform schwannomas arising from the posterior tibial nerve and its branch, which was located in a deep anatomic location and accompanied by a bony deformity.

• Journal of Gastric Cancer
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• v.21 no.2
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• pp.213-219
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• 2021

Plexiform fibromyxoma (PF) of the stomach is a very rare mesenchymal tumor of the gastrointestinal tract. We report the first case of PF with 2 different growth patterns pathologically confirmed after surgical resection. The tumor was characterized microscopically as infiltrative; it demonstrated diffuse growth into the smooth muscle bundles of the muscularis propria and was also multinodular and plexiform within the myxoid stroma. Immunohistochemical analysis revealed that the tumor cells were positive or weakly positive for smooth muscle actin, vimentin, and H-caldesmon and negative for desmin, CD117, CD34, CK-20, Pan-CK, Dog1, S100, ER, PR, and CD10. No mutations of C-kit and platelet-derived growth factor receptor alpha were detected. No genetic disruption of glioma-associated oncogene homolog 1 was detected by fluorescence in situ hybridization. The final diagnosis of PF was mainly based on the morphological and immunohistochemical findings.

• Journal of Korean Neurosurgical Society
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• v.44 no.5
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• pp.338-340
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• 2008

A rare case of ruptured aneurysm associated with multiple $A_1$ fenestrations resembling plexiform network was demonstrated by 3D angiography. A 56-year-old female presented with a ruptured aneurysm in the $A_2$ segment of the left distal anterior cerebral artery associated with the right $A_1$ fenestration. The ruptured aneurysm was occluded with surgical neck clipping via interhemispheric approach without neurological deficit. Plexiform fenestrations of the right distal $A_1$. opposite side to the left ruptured $A_2$ aneurysm, were clearly visible on postoperative 3D angiography. Our case may strongly support the theory described by Paget, namely that a remnant of the plexiform anastomosis between the primitive olfactory artery and $A_1$ segment is the source of such fenestration.

• Archives of Plastic Surgery
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• v.38 no.5
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• pp.679-682
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• 2011

Purpose: Neurofibromas of neuroectodermal origin are commonly found in Von Recklinghausens disease or neurofibormatosis type 1. It is an autosomal dominant disease caused by mutation of the long arm of chromosome 17. It can present from small nodules to disfiguring giant tumor. Plexiform neurofibroma is benign in most cases, but it could be transformed into malignant tumor, which requires surgical excision. To cover the defects after the excision, a number of surgical correction methods are available. This study is to report a surgical correction of disfiguring plexiform neurofibroma using anterolateral thigh free flap for extensive defects after surgical excision of neurofibrona. Methods: Data of five neurofibroma patients with an average age of 39 including medical history, physical examination, computed tomography, and magnetic resonance imaging were checked. No disease other than neurofibroma were detected. Biopsy on the excised tissues was performed. The follow-up period was 7 to 27 months. Results: The average size of defects after complete excision of neurofibroma was $13{\times}10{\sim}25{\times}15$ cm. Defects were covered by anterolateral thigh free flap, while donor sites were covered by local flap, split thickness skin graft and regional flap. Throughout follow-up, there were no complication, relapse, or any abnormalities. Conclusion: Despite various surgical correction methods are applicable to defects after excision on disfiguring plexiform neurofibroma, coverage of massive defects is still challenging in plastic and reconstructive surgeon. We have made five successful cases of surgical correction of disfiguring plexiform neurofibroma using anterolateral thigh free flap.

• Korean Journal of Veterinary Research
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• v.39 no.3
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• pp.407-416
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• 1999

This study was carried out to investigate the NPY-immunohistochemical characteristics of the olfactory bulb in the striped field mouse(Apodemus agrarius). The animals were anesthesized with thiopental sodium and perfused with 4% paraformaldehyde through left ventricle and aorta. Brains were removed and tranfered 10%, 20% and 30% sucrose. Sections were then cut on a cryostat into $40{\mu}m$-thick. The tissue immunostained with avidin-biotinylated complex method. The main olfactory bulb consisted of seven circumferential laminae : an olfactory nerve fiber layer, a glomerular layer with glomeruli surrounding by periglomerular cells, an external plexiform layer having granule and tufted cells, a mitral cell layer, a narrow internal plexiform layer, a granule cell layer forming several cell rows and a layer of white matter. The accessory olfactory bulb had four layers : an olfactory or vomeronasal nerve fiber layer, a glomerular layer consisting of small glomeruli, a mixed layer not distinguishing the external plexiform/mitral cell/granule cell layers and a granule cell layer. Most of NPY-immunoreactive(NPY-IR) neurons in main olfactory bulb were localized in the deeper portion of granule cell layer, white matter and anterior olfactory nucleus. In addition, some NPY-IR neurons were identified in the external plexiform layer. The shape of NPY-IR neurons of all olfactory bulb were predominant round or oval, sometime multipolar in shape. And most NPY-IR processes were parallel to long axis of white matter. In accessory olfactory bulb, NPY-IR neurons were not found in all region.

• Journal of Korean Ophthalmic Optics Society
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• v.5 no.2
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• pp.15-20
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• 2000

The morphology of dopaminergic neurons in the adult ox retina was studied. The dopaminergic neurons were identified using antibody immunocytochemistry. The great majority of tyrosine hydroxylase - immunoreactive neurons were located at the innermost border of the inner nuclear layer. The processes were monostratified and ran laterally within layer 1 of the inner plexiform layer. The second major population of tyrosine hydroxylase - immunoreactive neurons was displaced amacrine cells. The processes of displaced tyrosine hydroxylase - immunoreactive amacrine cells were also located within layer 1 of the inner plexiform layer. Some processes of a few neurons were located in the outer plexiform layer. A very low density of neurons had additional bands of tyrosine hydroxylase - immunoreactive processes in the middle and deep layers of the inner plexiform layer. The processes of dopaminergic neurons widely extended radially and formed large, moderately branched dendritic fields. These processes occasionally had varicosities but did not have "dendritic rings". These results indicate that dopaminergic cells make up specific neuronal cell types in the ox retina.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.2
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• pp.247-252
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• 2014

Purpose: This study was to investigate the properties and the location of neural reorganization following eccentric viewing training. Methods: 14 subjects with normal vision took part in eccentric viewing training. The measurements of the light sensitivity and multifocal electroretinogram were performed before and after the training. Results: The measurements of the light sensitivity and multifocal electroretinogram for pre-eccentric viewing training and post-eccentric viewing training showed the significant difference (p<0.047 and p<0.028, respectively). Conclusions: The retinal outer plexiform layer is unable to regenerate. However, the neural reorganization in the retinal outer plexiform layer is able to take place following eccentric viewing training.