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Sun-Won Park

Publications and source records attributed to Sun-Won Park.

9 recordsLinked to original sources
PubMed2006

Orbital abscess from an odontogenic infection.

An orbital abscess is a rare but serious complication of an odontogenic infection, which can lead to loss of vision or worse. This paper presents a case of orbital abscess secondary to an infection from the upper molar teeth, which extended to the retobulbar and posterosuperior region of the orbit, close to the superior orbital fissure. The infection spreaded to the pterygopalatine and infratemporal fossa and then to the orbit via the inferior orbital fissure. This paper reviews the clinical presentation, differential diagnosis, route of spread, value of serial CT scanning, treatment and possible complications.

Abscess↗
PubMed2005

Clustered localized pigmented villonodular synovitis.

The localized form of pigmented villonodular synovitis (PVNS) is a rare pathologic entity characterized by limited involvement of the synovium. In the knee joint, which is the most commonly affected joint, the disorder generally presents as a single nodular lesion, or rarely as 2 or 3 multiple nodular lesions into the joint. We report 2 cases of localized PVNS in which multiple nodules were clustered in a limited patella fat pad area. Clustered, multiple nodular lesions in a limited area suggested to us to consider a variant of localized forms.

Adult↗
PubMed2004

Lipoma arborescens of the knee.

Lipoma arborescens are rare lesions, typically located in the knee. They have a predilection for the suprapatellar pouch in the knee joint, but can also occur in any area of the knee joint. Magnetic resonance imaging of lipoma arborescens often reveals subchondral bone cyst and/or bone erosions, and there may appear to be a correlation between lipoma arborescens and osteoarthritis. We describe a case of histologically proven lipoma arborescens in the suprapatellar pouch and infrapatellar area of the knee with no damage to the posterior compartment and bone erosion in the proximal tibia without osteoarthritis.

Adipose Tissue↗
PubMed2004

Pigmented villonodular synovitis of the temporomandibular joint: MR findings in four cases.

OBJECTIVE: Although it is a rare condition, pigmented villonodular synovitis (PVNS) may involve temporomandibular joint (TMJ). The purpose of this study was to describe magnetic resonance (MR) findings of PVNS of the TMJ. METHODS AND MATERIAL: Between April 1992 and August 2000, four patients (two men and two women, 22-58-year-old) who had histologically proven diagnoses of PVNS in their TMJ were found in our institution. Their MR findings were reviewed retrospectively, and were correlated with pathologic findings. RESULTS: In all four patients, MR images invariably showed profound hypointensity on both T1- and T2-weighted sequences. This finding was seen diffusely and homogeneously throughout the lesion, and was considered to be due to paramagnetic effect attributed to heavy hemosiderin pigmentation, which was revealed by histopathological examination. MR images also showed aggressive nature of the lesions with adjacent skull base destruction and intracranial extension in two of them. CONCLUSION: As is the case in the other anatomic site, PVNS of the TMJ can be confidently diagnosed on MR imaging on the basis of the presence of hemosiderin. MR imaging also plays a pivotal role in surgical planning by precise and detailed localization of the lesion.

Adult↗
PubMed2003

Mesectodermal leiomyosarcoma of the ciliary body.

We report a case of low-grade mesectodermal leiomyosarcoma of the ciliary body, an extremely rare tumor of neural crest origin, occurring in a 12-year-old boy. MR imaging showed a well-marginated, ovoid soft tissue mass at the right temporal ciliary body, accompanied by total retinal detachment. The mass was slightly hyperintense relative to contralateral vitreous on T1-weighted images and markedly hypointense on T2-weighted images and enhanced very well. Initial biopsy of the mass suggested a peripheral nerve sheath tumor. The mass grew rapidly after biopsy, and enucleation was performed. The final diagnosis based on histology and immunohistochemistry was a low-grade mesectodermal leiomyosarcoma. To our knowledge, this is the first reported case of a malignant form of mesectodermal leiomyoma of the ciliary body.

Child↗
PubMedDate not supplied

Chronic, reactive conditions of the oral cavity simulating mucosal carcinomas: CT and MR imaging findings with pathologic correlation in five patients.

To investigate the radiologic and pathologic findings of chronic, inflammatory, reactive conditions of the oral cavity, which clinically and radiologically simulate mucosal malignancy, computed tomography (CT; n=4) and magnetic resonance (MR; n=2) images, as well as surgical specimens, obtained from five patients with surgically proved, chronic inflammatory mass of the oral cavity were retrospectively reviewed. All patients had a palpable mass or ulcerative lesion in the oral cavity. On CT and MR images, all three lesions in the oral tongue and one lesion in the retromolar trigone were seen as a superficial, ill-marginated, well-enhancing ellipsoid or focal soft tissue mass. Pathologic examinations revealed various depths and degrees of acute and chronic inflammation, granulation tissue, and fibrosis in the subepithelial stroma, accompanied by pseudoepitheliomatous hyperplasia in these four patients. In the remaining one patient with lesion in the hard palate, CT showed a relatively well-marginated, well-enhancing soft tissue mass, which histologically proved to be irritation fibroma. Neither clinical nor radiologic manifestations could afford clues to make the correct diagnosis, which therefore should rely on histology. Some forms of chronic, inflammatory, reactive conditions of the oral cavity are nearly indistinguishable from the malignant tumors both clinically and radiologically. Knowledge of this entity may obviate the unnecessary and somewhat disfiguring operation.

Adult↗
PubMedDate not supplied

Single shot fast spin echo diffusion-weighted MR imaging of the spine; Is it useful in differentiating malignant metastatic tumor infiltration from benign fracture edema?

PURPOSE: This study aims to evaluate the usefulness of single shot fast spin echo diffusion-weighted MR imaging (DWSSFSE) in differentiating malignant metastatic tumor infiltration of vertebral bone marrow from benign vertebral fracture edema. MATERIALS AND METHODS: Forty-six consecutive patients with 59 acute osteoporotic or traumatic vertebral fractures (mean age = 59) and 31 patients with 98 vertebral metastasis including 20 pathologic fractures (mean age = 53) were included in this study. Diffusion-weighted MR images were obtained by single-shot fast spin echo technique with diffusion gradient (b = 500 s/mm2, TR/TE: 5002/99) by using a 1.5 T MR scanner (Signa MR/i; GE Medical Systems, Milwaukee, WI, USA). T1- and T2-weighted images and short inversion time inversion-recovery (STIR) images were available in all 157 lesions, while contrast-enhanced images were available in 98 metastatic lesions. We evaluated signal intensity patterns on DWSSFSE in 157 lesions, which showed low signal intensity on T1-weighted images in both benign fractures and metastasis. The lesions on DWSSFSE were categorized as low, intermediate, and high signal intensity relative to presumed normal vertebra by concordant inspection of two experienced musculoskeletal radiologists. RESULTS: In benign fractures, DWSSFSE images showed low signal intensity in 56 vertebrae (95%) in 43 patients (93%) and intermediate signal intensity in only 3 vertebrae (5%) in 3 patients (7%). On the other hand, metastases most commonly had low signal intensity in 57 vertebrae (58%) in 25 patients (80%), intermediate signal intensity in 35 vertebrae (36%) in 16 patients (52%), and high signal intensity in 6 vertebrae (6%) in 3 patients (10%). Thus, intermediate and high signal intensities are far more common than benign fractures. Such differences in signal intensity were statistically significant (chi-square test, P < .05). High or intermediate signal intensity on DWSSFSE was highly specific for the diagnosis of metastatic tumor infiltration of the spine (sensitivity: 42%; specificity: 95%; true positive rate: 93%; false negative rate: 52%). CONCLUSIONS: DWSSFSE of the spine may be useful in differentiating metastatic tumor infiltration of vertebral bone marrow from benign fracture edema.

Diagnosis, Differential↗
PubMedDate not supplied

Nodular fasciitis in the head and neck: CT and MR imaging findings.

BACKGROUND AND PURPOSE: The purpose of this study was to describe the CT and MR imaging findings of nodular fasciitis occurring in the head and neck region. METHODS: CT (n = 6) and MR (n = 4) images obtained from 7 patients (3 men and 4 women; mean age, 19.4 years; age range, 1-48 years) with surgically confirmed nodular fasciitis in the head and neck were retrospectively reviewed. All patients presented with a palpable mass in the head and neck that was noticed 1-3 months earlier: 5 in the face, one in the occipital scalp, and the remaining one in the supraclavicular fossa. We investigated the CT and MR imaging characteristics with emphasis on the location, size, internal content, margin, enhancement pattern, and signal intensity of the lesion. RESULTS: All lesions appeared as a discrete mass on imaging, ranging from 1.0 cm to 4.6 cm in diameter (mean, 2.2 cm). Six lesions, all of which appeared benign, were located in the subcutaneous tissue superficial to the deep cervical fascia. The remaining lesion was located deep to the temporalis muscle and showed an aggressive imaging appearance, markedly eroding the bony orbit and skull. Five lesions were solid, and 2 lesions were partly or completely cystic in appearance. Five lesions were well defined, whereas 2 lesions were ill defined. Four of 5 solid lesions showed moderate to marked diffuse enhancement, whereas the remaining lesion demonstrated mild enhancement. Two cystic lesions showed peripheral, nodular, or rim-like enhancement. Compared with muscle, both solid lesions had isointense signal intensity on T1-weighted images and hyperintense signal intensity on T2-weighted images, whereas the signal intensity of the solid portions of the deep-seated, partly cystic lesion was isointense on both T1-weighted and T2-weighted images. CONCLUSION: Although rare, nodular fasciitis occurs as a discrete solid or cystic mass in the head and neck, depending on the predominant stromal components. When one sees a head and neck mass with a superficial location and moderate to marked enhancement on CT and MR imaging, nodular fasciitis should be included in the differential diagnosis, especially in patients with a recently developed, rapidly growing mass and a history of recent trauma.

Adolescent↗