Clinico-radiologic findings of entrapped inferior oblique muscle in a fracture of the orbital floor.

A 51-year old man presented with vertical and torsional diplopia after reduction of a blowout fracture at another hospital one year ago. He had no anormalies of head position and 14 prism diopters (PD) right hypertropia (RHT) in the primary position. In upgaze no vertical deviation was found, and hyperdeviation on downgaze was 35PD. Bielschowsky head tilt test showed a negative response. Distinct superior oblique (SO) and inferior rectus (IR) underaction of the right eye was noted but IO overaction was mild on the ocular version test. Double Maddox rod test (DMRT) revealed 10-degree extorsion, but fundus extorsion was minimal in the right eye.Thin-section coronal CT scan showed that there was no fracture line on the anterior orbital floor, but a fracture remained on the posterior orbital floor. Also, the anterior part of the right inferior oblique muscle was vertically reoriented and the medial portion of the inferior oblique muscle was not traced on the coronal CT scan. The patient underwent 14 mm right IO recession and 3 mm right IR resection. One month after the surgery, his vertical and torsional diplopia were eliminated in the primary position.

Sonographically guided fine needle aspiration of thyroid nodule: discrepancies between cytologic and histopathologic findings.

PURPOSE: To analyze the discrepancies between the cytologic results of sonographically (US)-guided fine needle aspiration (FNA) of thyroid nodules and final histopathologic results and to discuss the limitations of US-guided FNA. MATERIALS AND METHODS: The results of US-guided FNAs performed by a single experienced radiologist in 315 thyroid nodules in 292 patients (246 women, 46 men aged 12-79 years) were retrospectively correlated with their surgical pathologic results. The FNA results were classified as nondiagnostic, indeterminate, negative, or positive, whereas final pathologic diagnoses were classified as malignant or benign. RESULTS: The FNA results were nondiagnostic in 31 cases (9.8%), indeterminate in 97 cases (30.8%), and determinate in 187 cases (59.4%). Of the 187 conclusive cases, 169 (90.4%) were concordant with the final pathologic results, whereas 18 (9.6%) were discordant with 14 false-positive and 4 false-negative results. These discrepancies were caused by atypical nuclear features. Among the 97 indeterminate and 31 nondiagnostic cases, a malignancy was found in 14 (14.4%) and 8 (25.8%) cases, respectively. In addition, 10 papillary carcinomas, which were not visualized on sonograms, were detected incidentally in thyroidectomy specimens. CONCLUSION: The diagnostic accuracy of US-guided FNA of thyroid nodule has limitations that should be minimized by careful interpretation of the cytologic findings and accurate sampling.

Diffusion-weighted magnetic resonance imaging in the syndrome of acute bilateral basal ganglia lesions in diabetic uremia.

In this report, we have presented a diabetic patient with uremia, in which acute Parkinsonism occurred, coupled with acute mental confusion, after a sudden increase in blood urea nitrogen and serum creatinin levels. Diffusion-weighted magnetic resonance imaging revealed a unique cytotoxic-type edema in the bilateral basal ganglia during the acute phase. Signal alterations were shown to regress in accordance with the normalized apparent diffusion coefficient (ADC) values, but irreversible cystic degeneration developed in the globus pallidus, with the very low preceding ADC values.

Inflammatory myofibroblastic tumor of the larynx.

BACKGROUND: Inflammatory myofibroblastic tumor, composed of myofibroblastic spindle cells with acute and chronic inflammatory cells, is an unusual, benign solid mass that mimics a neoplastic process. METHODS: We report a rare case of a patient with a laryngeal inflammatory myofibroblastic tumor. Laryngoscopy demonstrated a submucosal mass involving the right false cord. The mass was a well-enhanced supraglottic lesion on CT scan. It showed medially high signal intensity and peripherally low signal intensity on T2-weighted MR images, and it displayed a high magnetization transfer ratio; before surgery, it was believed to be a malignant tumor. Laryngoscopic biopsy was performed. Pathologic features of the specimen were diagnostic for inflammatory myofibroblastic tumor. RESULTS: Steroid therapy was chosen for further treatment. No recurrence was observed for 4 years. CONCLUSION: In patients with chronic hoarseness who have a malignant-looking submucosal laryngeal mass, inflammatory myofibroblastic tumor should be considered. Conservative surgery and steroid treatment are advocated because of laryngeal preservation.

Detailed nodal features of cervical tuberculous lymphadenitis on serial neck computed tomography before and after chemotherapy: focus on the relation between clinical outcomes and computed tomography features.

OBJECTIVE: To investigate the relation between clinical outcomes and nodal features on computed tomography (CT) in cervical tuberculous lymphadenitis (CTBL) before and after antituberculous chemotherapy. METHODS: Fifty-six patients with CTBL underwent CT before and after a 6- or 12-month course of standard chemotherapy. Three radiologists evaluated the nodal features on serial CT retrospectively, including calcification (no/punctuate/large), necrosis (no/eccentric/central), perinodal infiltrations (no/localized/extensive), and enhancing patterns (no/peripheral/homogeneous). The clinical outcome was defined as "favorable" (n = 33) or "unfavorable" (n = 23) at the completion of chemotherapy. RESULTS: All the features on the initial CT scan did not show a statistically significant difference between the favorable and unfavorable groups. On the final CT scan, absence of necrosis (P < 0.005), no infiltration (P < 0.005), no enhancement (P < 0.008), and central enhancement (P < 0.014) were more common in the favorable group, whereas large necrosis (P < 0.005), localized and extensive infiltration (P = 0.005, P < 0.005), and peripheral enhancement were more common in the unfavorable group (P < 0.005, P = 0.009). CONCLUSIONS: Central necrosis, perinodal infiltration, and peripheral rim enhancement on the final CT scan showed differences between the 2 groups. These CT features reflecting inflammation can be useful findings for assessing treatment response.

Cerebral white matter lesions and hypertension status in the elderly Korean: the Ansan Study.

There is evidence of an association of hypertension with white matter lesions (WMLs), leukoaraiosis, in the human brain in the United States, Europe and Japan. However, no study on this association has been reported in Korea. Community-dwelling elderly subjects aged over 61 years were randomly selected from samples of the Ansan Health Study, while their blood pressures (BPs) were measured using a highly standardized protocol. Hypertension was defined as a systolic BP> or =140 mmHg or a diastolic BP> or =90 mmHg or as reported treatment with hypertensive medication, and further subclassified with respect to its subtypes and control status. WMLs were determined by a 1.5-T MRI scan and further categorized into five subgroups with respect to its severity. Hypertension status, such as uncontrolled hypertension even after antihypertensive medication (adjusted odd ratio [OR]=6.07; 95% CI, 2.08-17.78), isolated systolic hypertension before medication (OR=2.66; 95% CI, 1.08-6.57), and hypertension before medication (OR=2.55; 95% CI, 1.19-5.46) were significantly and independently correlated with the presence and severity of WMLs. Advancing age (OR=1.76; 95% CI, 1.38-2.25), lacunar infarction (OR=3.19; 95% CI, 1.83-5.58), and cigarette smoking (OR=1.10; 95% CI, 1.03-1.18) were significantly related to the presence and severity of WMLs. Regular and tight control for hypertension should be exercised to prevent WMLs among the elderly with hypertension.

Fluid infusion technique for ultrasound-guided percutaneous nephrostomy.

We describe a simple but useful technique for improving the visualization of the needle during ultrasound-guided percutaneous nephrostomy, especially suitable for obese patients.

Acinic cell carcinoma of the head and neck: radiologic-pathologic correlation.

OBJECTIVE: To describe and correlate the imaging and pathologic findings of acinic cell carcinoma (ACC) in the head and neck. METHODS: We reviewed the radiologic findings of 12 patients with pathologically proven ACC in the head and neck. They were 6 males and 6 females (ages: 5-75 years, mean 36 years) who undergoing computed tomography (CT, n=9) and CT with magnetic resonance (MR) imaging (n=3). RESULTS: The lesions in the superficial lobe of the parotid gland were solid (n=7), cystic (n=1), and cystic mass with mural nodule (n=1) on CT. A parapharyngeal lesion was cystic mass with mural nodule, and a submandibular and a palate tumor were cystic lesions on CT. All solid masses in the parotid gland (n=7) included focal low-attenuating portions on CT, which were microcyst, hemorrhage, or necrosis on pathologic examination. We could not find intratumoral calcifications or metastatic lymphadenopathy on imaging and histologic studies in all 12 cases. Internal hemorrhage on the MR images was seen in a parapharyngeal and a parotid lesion. CONCLUSION: Although ACC appears to have nonspecific imaging findings, familiarity with some imaging features can be helpful for differential diagnosis of head and neck tumors.

Age-related changes in conventional and magnetization transfer MR imaging in elderly people: comparison with neurocognitive performance.

OBJECTIVE: This study was designed to compare three different measures of the elderly human brain; the magnetization transfer ratio (MTR) histogram, the percentage of brain parenchymal volume, and the volume of T2 hyperintense areas in terms of correlations with the study subjects neurocognitive performance. MATERIALS AND METHODS: Thirty-five healthy community-dwelling elderly volunteers aged 60-82 years underwent dual fast spin-echo (FSE) imaging and magnetization transfer imaging. A semi-automated technique was used to generate the MTR histogram, the brain parenchymal volume, and the T2 lesion volume. The subjects' neurocognitive performance was assessed by using the Korean-Mini Mental State Examination (K-MMSE) and additional tests. The peak height of the MTR (PHMTR), the percentage of brain parenchymal volume (PBV), and the normalized T2 lesion volume (T2LV) were compared between the normal group (Z score on the K-MMSE>/=-2, n=23) and the mild cognitive impairment group (Z score on the K-MMSE < -2, n=12), and these parameters were correlated with age and various neurocognitive performance scores. RESULTS: The PHMTR was significantly lower in the cognitively impaired subjects than the PHMTR in the normal subjects (p = 0.005). The PBV scores were lower in the cognitively impaired subjects than in the normal subjects (p = 0.02). The T2LV scores were significantly higher in the cognitively impaired subjects (p = 0.01). An inverse correlation was found between the PHMTR and T2LV (r = -0.747, p < 0.001), and also between the PBV and T2LV (r = -0.823, p < 0.001). A positive correlation was observed between the PHMTR and the PBV (r = 0.846, p < 0.001). Scores on the various neurocognitive tests were positively correlated with the PHMTR (6 of 7 items) and the PBV (5 of 7 items), and they were negatively correlated with the T2LV (5 of 7 items). CONCLUSION: Our findings of a correlation among the PBV, the T2LV, and the PHMTR suggest that MTR histograms and the PBV and T2LV can be used as a reliable method and valid statistical tool, respectively, for quantifying the total lesion burden in an aging brain.

CT findings in Kikuchi disease: analysis of 96 cases.

BACKGROUND AND PURPOSE: Although CT findings of Kikuchi disease (KD), or histiocytic necrotizing lymphadenitis, are reported in several case reports, large-scale analysis of the disease has not been undertaken. We characterized the clinical and CT findings in a large group of patients with KD. METHODS: Between 1990 and 2002, 96 patients (68 women, 28 men; mean age, 24.4 years) underwent biopsy of the cervical lymph nodes and had histologically proved KD at our institution. We reviewed their clinical and CT findings and recorded the total number of affected nodes; location and size of the lymph nodes; and characteristic findings including necrosis, perinodal infiltration, and contrast enhancement. RESULTS: We identified 1196 affected lymph nodes (12.5 nodes per patient). The affected lymph nodes were 0.5-3.5 cm (mean, 1.62 cm). Perinodal infiltration was found in 78 patients (81.3%). Eighty (83.3%) had homogeneous nodal contrast enhancement. Nine patients (9.4%) had lymph nodes with a focal low attenuation, and seven (7.3%) had ring-shaped lymph nodes. Unilateral and bilateral cervical lymph nodes were affected in 76 and 20 patients, respectively. Lymph nodes were mainly located at levels II (IIA, 174 nodes; IIB, 254 nodes), III (222 nodes), IV (160 nodes), and V (VA 126 nodes, VB 130 nodes). Follow-up CT in 32 patients showed complete resolution in 14 and partially improved lymphadenopathy in 18. CONCLUSION: Awareness of the various CT appearances of KD and follow-up CT may be helpful for more accurate diagnosis of the disease.

Maple syrup urine disease encephalopathy: a follow-up study in the acute stage using diffusion-weighted MRI.

Neonatal maple syrup urine disease (MSUD) is associated with diffuse oedema and characteristic MSUD oedema. We present a newborn infant with two coexisting different types of oedema. The myelinated white matter showed a marked decrease in the water apparent diffusion coefficient (ADC) compatible with cytotoxic oedema. The unmyelinated white matter showed an increase in ADC, consistent with vasogenic-interstitial oedema. On follow-up studies, the cytotoxic oedema showed improvement, but the vasogenic-interstitial oedema progressed into brain atrophy.

Moyamoya disease in a child with previous acute necrotizing encephalopathy.

A previously healthy 24-day-old boy presented with a 2-day history of fever and had a convulsion on the day of admission. MRI showed abnormal signal in the thalami, caudate nuclei and central white matter. Acute necrotising encephalopathy was diagnosed, other causes having been excluded after biochemical and haematological analysis of blood, urine and CSF. He recovered, but with spastic quadriparesis. At the age of 28 months, he suffered sudden deterioration of consciousness and motor weakness of his right limbs. MRI was consistent with an acute cerebrovascular accident. Angiography showed bilateral middle cerebral artery stenosis or frank occlusion with numerous lenticulostriate collateral vessels consistent with moyamoya disease.

Imaging findings of mantle cell lymphoma involving gastrointestinal tract.

Clinical manifestations and imaging findings of mantle cell lymphoma involving gastrointestinal tract were evaluated. The subjects were 7 cases of mantle cell lymphoma involving the gastrointestinal tract. All cases were pathologically confirmed in our hospital during the period from April 1994 to July 2000. Five patients were male and 2 were female, and their age ranged from 49 to 63 years (average 57.4). The objectives were: 1) characteristics and distribution of multiple polyposis, 2) presence, location and enhancement pattern of bowel wall thickening or mass formation, 3) presence of splenomegaly, 4) presence and location of abdominal lymph node enlargement, 5) involved extra-abdominal organs, 6) combined cancer and location, and 7) other findings. All mantle cell lymphomas occurred in elderly persons, over 40 years, and most showed multiple polyposis (6/7), bowel wall thickening or mass formation (6/7), lymph node enlargements (6/7) and extra- abdominal involvement (5/7). All cases of polyposis involved the small bowel and colon, and the size of the polyps ranged from 0.1-4.0cm. Four of 6 patients showed combined sessile and polypoid polyps, while the other 2 showed only sessile polyps. Most of or some of the polyps in 3 patients showed small central ulcerations. Most of the patients (5/6) showed an uncountable number of polyps. Polyposis was predominant in the rectum, ascending colon, rather than other sections in the colon, and the ileum were almost always involved by polyposis. Bowel wall thickening or mass formation developed exclusively in the ascending colon, rectum or ileum. Extra- abdominal involvement developed either simultaneously or nonconcurrently with gastrointestinal involvement. Some of patients showed splenomegaly (3/7), appendiceal enlargement (2/7), and intussusception (1/7), and some had associated adenocarcinomas (3/7).