Management and infection control practices in a Taiwanese radiology department during the COVID-19 outbreak.

The radiology department was categorized as a "high risk area" during the severe acute respiratory syndrome (SARS) outbreak in 2003 and is similarly considered a "high risk area" during the current coronavirus (COVID-19) pandemic. The purpose of infection control is to isolate patients with suspected or confirmed COVID-19 from uninfected people by utilizing separate equipment, spaces, and healthcare workers. Infection control measures should be prioritized to prevent the nosocomial spread of infection. We established a COVID-19 infection control team in our radiology department. The team's responsibilities include triaging patients with confirmed or suspected COVID-19, performing imaging and reporting, using dedicated equipment, disinfecting the equipment and the immediate environment, and staff scheduling.

Osseous Injury Associated With Ligamentous Tear of the Knee.

One of the most common knee injuries is ligament tear, which may initially manifest as an osseous injury in radiographs. Radiologists should therefore be able to recognize ligament tears of the knee as osseous abnormalities in images. This review focuses on the imaging features of knee ligament injuries and their related osseous injuries: anterior cruciate ligament (ACL) tear with Segond fracture; associated marrow contusion; ACL avulsion fracture; posterior cruciate ligament (PCL) tear with osseous avulsion of the ligament including arcuate sign; reverse Segond fracture; PCL avulsion fracture; medial collateral ligament tear with Pellegrini-Stieda disease; lateral collateral ligament tear with avulsion fracture of the fibular head; and patellar ligament injuries with Osgood-Schlatter and Sinding-Larsen-Johansson.

The effectiveness of N-Acetylcysteine in preventing contrast-induced nephropathy in patients undergoing contrast-enhanced computed tomography: a meta-analysis of randomized controlled trials.

BACKGROUND: N-Acetylcysteine (NAC) is reported to have potential for preventing of contrast-induced nephropathy (CIN) in patients undergoing coronary angiography. However, the effectiveness of NAC in preventing CIN in patients undergoing contrast-enhanced computed tomography (CT) is still controversial. We conducted a meta-analysis of relevant randomized controlled trials (RCTs) to further examine this issue. METHODS: RCTs were identified by computerized searching in PubMed, EMBASE, SCOPUS, and Cochrane databases. Two reviewers independently assessed the methodological quality of each study. A meta-analysis was performed to evaluate the effectiveness of NAC in preventing CIN in patients undergoing CT. The primary outcome was the incidence of contrast-induced nephropathy, and the requirement for dialysis. The secondary outcome was the change of serum creatinine. RESULTS: Six randomized controlled trials were identified with a total of 496 patients meeting the criteria for this study. Prophylactic administration of NAC in patients with serum creatinine above 1.2 mg/dL undergoing contrast-enhanced CT, along with hydration, reduced the risk of CIN (relative risk 0.20; 95 % confidence interval: 0.07-0.57). Requirement for dialysis was not significantly different between the NAC group and the control group. CONCLUSIONS: This review provides evidence of the efficacy of NAC in preventing the incidence of CIN and recommends that NAC be more widely used in high-risk patients undergoing contrast-enhanced CT. On the basis of the evidence reviewed, further research involving large RCTs may be warranted.

Sacrococcygeal teratoma in an adolescent.

Sacrococcygeal teratoma (SCT) is a neoplasm derived from more than one primitive germ cell layer. SCTs have rarely been reported in adults. We present a case of a 17-year-old youth who complained of a painful mass over his left buttock.The mass had been growing gradually since his childhood. Magnetic resonance imaging showed a well-defined soft-tissue mass which contained mainly fat tissue and large intestine. The patient had complete excision of the tumor and coccyx.The gross impression and histology revealed a mature teratoma.

Rapid staining and immediate interpretation of fine-needle aspiration cytology for palpable breast lesions: diagnostic accuracy, mammographic, ultrasonographic and histopathologic correlations.

OBJECTIVE: We investigated the role and turn around time of rapid staining and immediate interpretation of fine-needle aspiration cytology (FNAC) for women with palpable breast lesions. STUDY DESIGN: A total of 408 FNAC specimens from 400 patients with palpable breast lesions was analyzed for immediate interpretation and preliminary cytologic diagnosis. All cytological diagnoses were correlated with subsequent alcohol-fixed Papanicolaou-stained slides, mammographic, ultrasonographic and histopathological findings. RESULTS: Of the 408 specimens, 243 (59.6%) were interpreted as benign, 37 (9.0%) atypical, 22 (5.4%) suspicious, 68 (16.7%) malignant, and 38 (9.3%) unsatisfactory. 132 of 408 (32.4%) had subsequent surgical procedures; the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 88.5, 100, 100, 81.9 and 92.4%, respectively. The average turn around time was 8.6 min. Mammographic results were available in 242 (59.3%) cases, with 112 (46.3%) undergoing surgical excision. In correlation with mammography and surgical pathology, the false-positive rate, false-negative rate, sensitivity, specificity and accuracy were 1.9, 10.5, 98.1, 89.5 and 95.8%, respectively. CONCLUSIONS: Rapid FNAC interpretation is a useful, effective diagnostic method for palpable breast lesions in our healthcare environment.

Creation of a reflecting formula to determine a patient's indication for undergoing total knee arthroplasty.

BACKGROUND: The aim of this study was to develop, from patients' characteristics and radiography, a formula reflecting the decision for total knee arthroplasty (TKA) in patients with a painful osteoarthritic knee. METHODS: We reviewed medical records of 193 consecutive patients who had knee osteoarthritis and underwent primary TKA surgery and 133 consecutive patients with knee osteoarthritis who did not have surgery in one institution during the preceding 5 years. Two skeletal radiologists graded, from 0 to 3, radiographic joint space narrowing (JSN), osteophytes, subchondral sclerosis, and subchondral cysts. The association between the variables and outcome were calculated by the chi-squared test and multivariable logistic regression. RESULTS: Women had more TKAs than men (P = 0.002), and the TKA and non-TKA groups differed in terms of self-care ability (P < 0.001). There were no significant differences in age or body mass index between the two groups. The relevant factors in the reflective formula were age, sex, self-care ability, JSN, and osteophytes in the medial compartment. The retrospective sensitivity and specificity for patients who underwent TKA surgery were 84% and 83%, respectively. The diagnostic efficacy in retrospect evaluated by a receiver operating characteristic curve was 0.92. CONCLUSIONS: A formula reflecting the decision for TKA surgery in patients with a painful osteoarthritic knee has been developed with acceptable diagnostic efficacy obtained retrospectively. The formula should be validated by further study.

Is there an association between epiphyseal scar and osteonecrosis of the femoral head?

PURPOSE: To investigate statistical association between epiphyseal scar and osteonecrosis of the femoral head (ONFH) with magnetic resonance (MR) imaging. PATIENTS AND METHODS: We retrospectively reviewed 71 consecutive patients who underwent MR imaging of bilateral hips that showed nontraumatic ONFH. There were 110 hips with ONFH and 31 normal hips; one hip received bipolar arthroplasty before the MR studies. All cases of ONFH had typical MR findings. The epiphyseal scars in the femoral head were classified as type I (a sealed-off scar) or type II (a perforated scar). Bone marrow edema, if present, in the proximal femur was identified on coronal T2-weighted or STIR MR images. RESULTS: The type of femoral epiphyseal scar was clearly delineated in 97 hips. In cases with ONFH, a type I scar occurred in 46 hips (64%), and a type II scar in 26 hips (36%). In cases of ONFH with bone marrow edema, 69% of hips (24/35) had a type I scar and 31% of hips (11/35) had a type II scar. There was no statistical association between the type of epiphyseal scar and ONFH, regardless of staging (P=0.29), or the type of scar and bone marrow edema (P=0.42). CONCLUSION: There is not a significant statistical association between a sealed-off scar and ONFH.

Intervertebral disk degeneration related to reduced vertebral marrow perfusion at dynamic contrast-enhanced MRI.

OBJECTIVE: The purpose of this study was to use dynamic contrast-enhanced MRI to ascertain the relation between intervertebral disk degeneration and lumbar vertebral marrow blood perfusion. SUBJECTS AND METHODS: We recruited 25 patients (50 vertebral bodies) who underwent dynamic contrast-enhanced MRI of the lumbar spine. The peak signal enhancement of each vertebral body was calculated from the time signal after curve fitting of a pharmacokinetic model. We controlled for other variables that might have affected blood perfusion by assessing two vertebral bodies in each patient. The 25 patients were divided into three groups. In group 1, one of the vertebral bodies (L1 or L3) evaluated was between two adjacent normal disks and the other was between two adjacent degenerated disks. In group 2, each of the two vertebral bodies evaluated was between two normal disks. In group 3 each of the two vertebral bodies evaluated was between two degenerated disks. RESULTS: Without normalization by minimization of other variables, there were no statistically significant differences in original peak enhancement values among groups 1, 2, and 3 (p = 0.179). After normalization, the peak enhancement in group 1 (0.846 +/- 0.060) was significantly lower than that in group 2 (0.988 +/- 0.047) (p = 0.003) or group 3 (0.973 +/- 0.081) (p = 0.008). CONCLUSION: After normalization, lumbar vertebral marrow perfusion correlated well with intervertebral disk degeneration evaluated with dynamic contrast-enhanced MRI. Blood perfusion was 14% less in the vertebral body marrow between two degenerated disks than in vertebral marrow between two normal disks.

MRI of hemangioblastoma in the conus medullaris.

Hemangioblastoma of the conus medullaris with MRI has not been reported before. A 75-year-old man had a history of falling due to weakness of his left lower limb. MRI revealed a well-defined oval mass in the conus medullaris. The tumor had an isointense signal relative to spinal cord on T1-weighted images, hyperintense signal areas intermixed with punctate spots of hypointensity on T2-weighted images, and heterogeneous obvious enhancement on gadolinium-enhanced T1-weighted images. Associated abnormally tortuous vessels were noted in the dura proximal to the tumor. Histological findings were compatible with the diagnosis of hemangioblastoma. Hemangioblastoma should be included in the differential diagnosis in patients with an enhancing tumor and adjacent engorged vessels of the spinal cord.

Magnetic resonance imaging of gluteal intramuscular myxoma.

Gluteal intramuscular myxomas with MR images have not been reported before. A 45-year-old man presented with a palpable mass in his right buttock for several months. Magnetic resonance imaging showed an intramuscular cystic lesion with homogeneous signal intensity at the right gluteus muscle, and the mass had thin peripheral enhancement after gadolinium administration. The patient was treated by marginal excision of the tumor. Histologic diagnosis was compatible with intramuscular myxoma.

MRI of alveolar soft-part sarcoma.

Alveolar soft-part sarcoma (ASPS) is rare. We present a case of a 30-year-old woman with a 6-month history of a palpable mass in her left thigh. MRI showed an 8-cm mass and a satellite nodule at the left gluteus muscle. The main tumor exhibited an isointense signal on T1-weighted images and high-signal-intensity areas with low-signal-intensity scanty solid components on T2-weighted images. MR angiography showed dilated and tortuous veins around the tumor. Histologic findings were compatible with ASPS.

Intermuscular cavernous lymphangioma presenting with overgrowth of fat: MRI findings.

We present a case of an intermuscular cavernous lymphangioma with predominantly composed of fatty tissue. A 58-year-old man complained a palpable painless mass over his right arm for 1 month. Magnetic resonance imaging (MRI) showed a 14-cm mass with predominantly composed of fatty tissue between long and short heads of triceps muscle. There were some serpiginous structures with hyperintensity within the tumors on gradient-echo and gadolinium enhanced T1-weighted images. Histologic examination revealed a picture of intermuscular angioma predominantly composed of cavernous lymphangioma.

Tumoral calcinosis-like metastatic calcification in a patient on renal dialysis.

Tumoral calcinosis-like metastatic calcification in a patient with uremia on dialysis has rarely been reported in the radiological literatures. This report describes the radiographic, scintigraphic, ultrasound, and CT findings of this condition in a 54-year-old man who had a clinical history of renal dialysis for 6 years. Elevation of serum phosphate and parathyroid hormone levels was noted. Physical examination revealed a hard, movable, and tender mass over his left arm. Plain radiographs of the left shoulder showed an amorphous massive calcification in the upper arm. Scintigraphy showed increased tracer accumulation in the soft tissue of the proximal portion of the left arm and both thighs, where CT scan revealed multilocular, amorphous, calcified masses in these areas. Scintigraphy can help in screening multiple lesions, and CT scan may further help in identifying the extent of a localized lesion such as joint involvement. Ultrasound showed localized multiloculated fluid accumulation within hyperechoic masses and perifocal interstitial fluid collection, which can help to determine the activity of the lesion. Ultrasound findings of tumoral calcinosis have not been reported before.

Malignant fibrous histiocytoma of the female breast: a case report.

Malignant fibrous histiocytoma (MFH) of the breast is very rare. Sonographic findings of MFH of the breast have not been reported before. We herein report a case of a 46-year-old woman with a histologically proved MFH of her right breast. Ultrasound examination revealed a 6-cm tumor mass with solid and cystic components, which were attributed after histological examination to hypercellularity and hemorrhage within the tumor. Histopathological diagnosis was compatible with MFH of the breast.

MRI of hemangiopericytoma in the sacrum.

Osseous hemangiopericytoma is rare. We present a case of a 30-year-old woman with low-back pain with radiation to the left buttock for 1 month. Magnetic resonance imaging (MRI) showed a tumor mass with areas of serpentine signal void pattern in the sacrum suggestive of a vascular tumor. Neither calcifications nor layered blood serum were noted. Histological diagnosis was compatible with osseous hemangiopericytoma.

Radiographic appearance and clinical outcome correlates in 26 patients with severe acute respiratory syndrome.

OBJECTIVE: We aimed to evaluate the appearance of chest radiographs in patients with severe acute respiratory syndrome (SARS) and correlate these findings with clinical outcomes. MATERIALS AND METHODS: We retrospectively reviewed the initial radiograph and a series of follow-up chest radiographs in 26 patients who had symptoms and signs consistent with SARS. Twenty-five patients completed the full course of radiographs in the hospital. The initial radiographic features and the distribution of parenchymal, mediastinal, and pleural abnormalities for each patient were evaluated. Follow-up radiographic findings were correlated with clinical outcomes for these patients. RESULTS: Initial chest radiographs showed abnormalities in 23 (88%) of 26 subjects. Eighteen patients (69%) had air-space consolidation, two (8%) had ground-glass attenuation, one (4%) had nodules, and two (8%) had mixed consolidation and nodules. Four patients (15%) had pleural effusion. Younger patients and those with normal initial radiographic findings or unifocal lung lesions had better outcomes. CONCLUSION: The initial predominant radiographic feature of SARS was air-space consolidation in the lateral and lower lung zones. Progressive deterioration to diffuse unilateral or bilateral consolidation in the series of follow-up chest radiographs is associated with a poor prognosis.