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Biomedical subjects

Yi-Hong Chou

Publications and source records attributed to Yi-Hong Chou.

54 records · Page 3Linked to original sources
PubMed2003

Neonatal enterovirus infections: emphasis on risk factors of severe and fatal infections.

OBJECTIVES: Neonatal enterovirus infections have diverse manifestations, from asymptomatic to fatal. An understanding of the risk factors associated with severe cases might help to reduce enterovirus-related morbidity and mortality. METHODS: From July 1989 through June 1998, neonates with virus culture-confirmed nonpolio enterovirus infection at Chang Gung Children's Hospital were enrolled in the study and divided into three groups: nonspecific febrile illness; aseptic meningitis; and hepatic necrosis with coagulopathy (HNC). Demographic factors, clinical manifestations, laboratory data and outcome were analyzed to reveal factors associated with clinical severity and fatality. RESULTS: There were 146 cases including 43 neonates with nonspecific febrile illness, 61 with aseptic meningitis and 42 with HNC. By multiple logistic regression analysis, the most significant factors associated with HNC were prematurity, maternal history of illness, earlier age of onset (< or =7 days), higher white blood cell count (WBC > or =15 000/mm3) and lower hemoglobin (< or =10.7 g/dl). In 10 (24%) of 42 cases, HNC was fatal. In comparison with nonfatal cases of HNC, fatal cases had higher WBC, lower hemoglobin, higher bilirubin and higher incidence of concurrent myocarditis. Multivariate analysis showed the most significant factors associated with fatality from HNC to be total bilirubin >14.3 mg/dl (adjusted odds ratio, 29.1; 95% confidence interval, 2.5 to 355.5; P = 0.007) and concurrent myocarditis (adjusted odds ratio, 13.7; 95% confidence interval, 1.1 to 177.2; P = 0.04). Intravenous immunoglobulin did not correlate with clinical outcomes in cases with HNC. CONCLUSIONS: Prematurity, maternal history of illness, earlier age of onset, higher WBC and lower hemoglobin are significant factors associated with HNC; higher total bilirubin and concurrent myocarditis were most significantly associated with fatality from HNC.

Antiviral Agents↗
PubMed2003

Breast lesions on sonograms: computer-aided diagnosis with nearly setting-independent features and artificial neural networks.

PURPOSE: To develop a computer-aided diagnosis (CAD) algorithm with setting-independent features and artificial neural networks to differentiate benign from malignant breast lesions. MATERIALS AND METHODS: Two sets of breast sonograms were evaluated. The first set contained 160 lesions and was stored directly on the magnetic optic disks from the ultrasonographic (US) system. Four different boundaries were delineated by four persons for each lesion in the first set. The second set comprised 111 lesions that were extracted from the hard-copy images. Seven morphologic features were used, five of which were newly developed. A multilayer feed-forward neural network was used as the classifier. Reliability, extendability, and robustness of the proposed CAD algorithm were evaluated. Results with the proposed algorithm were compared with those with two previous CAD algorithms. All performance comparisons were based on paired-samples t tests. RESULTS: The area under the receiver operating characteristic curve (A(z)) was 0.952 +/- 0.014 for the first set, 0.982 +/- 0.004 for the first set as the training set and the second set as the prediction set, 0.954 +/- 0.016 for the second set as the training set and the first set as the prediction set, and 0.950 +/- 0.005 for all 271 lesions. At the 5% significance level, the performance of the proposed CAD algorithm was shown to be extendible from one set of US images to the other set and robust for both small and large sample sizes. Moreover, the proposed CAD algorithm was shown to outperform the two previous CAD algorithms in terms of the A(z) value. CONCLUSION: The proposed CAD algorithm could effectively and reliably differentiate benign and malignant lesions. The proposed morphologic features were nearly setting independent and could tolerate reasonable variation in boundary delineation.

Adolescent↗
PubMed2003

Duplex Doppler ultrasound of hepatic Schistosomiasis japonica: a study of 47 patients.

This study describes the ultrasound (US) appearances of the liver with hepatic schistosomiasis japonica (HSJ), and studies the portal hemodynamics in 47 patients with HSJ using duplex Doppler US over a period of 15 years. All patients but two were Chinese war veterans seen in Taiwan about 35-55 years after their presumed infection in Mainland China. The US presentations were reviewed. The data from Doppler portal flow studies were available for 39 patients with HSJ, and compared to data from Doppler portal flow studies in 40 normal healthy volunteers and to this data in 40 patients with postnecrotic cirrhosis. A typical "coarse reticular pattern" due to fibrosis in the whole liver was noted in 40 patients (85%). Other findings included periportal fibrosis (15%), septum-like fibrous bands extending to the liver capsule (32%), and an apparent nodular liver surface (19%). Splenomegaly was noted in seven patients. While coexisting hepatocellular carcinomas (HCC) were evident in three patients, and esophageal varices were found in three others, yet both conditions were found only in patients with positive hepatitis-B-surface antigen (HBsAg). Doppler flowmetry of the portal veins in HSJ patients showed a mean flow rate of 15.34 +/- 6.82 cm/sec, and a mean flow volume of 993.21 +/- 290.63 ml/min, both showed no significant difference from those in normal adults (p > 0.5). HSJ can be confidently diagnosed in patients with hepatic fibrosis when the hepatic pathology is presented as a coarse reticular pattern. The portal hemodynamics in HSJ patients who have been isolated from the infection site (for more than 35 years) are significantly different from portal hemodynamics in cirrhotic patients and are similar to those in healthy volunteers.

Aged↗
PubMed2002

Solitary metastasis from renal cell carcinoma presenting as diffuse pancreatic enlargement.

Late metastasis of renal cell carcinoma (RCC) to the pancreas is uncommon. Diffuse pancreatic metastasis of any carcinoma rarely causes global enlargement of the pancreas. We present the case of a 73-year-old man diagnosed with metastatic RCC of the pancreas 9 years after radical nephrectomy had been performed and describe our radiologic findings. The disease involved the entire pancreas, which was hypoechoic on sonography, hypodense on CT without contrast enhancement, and markedly hyperdense after intravenous administration of a contrast agent. Color Doppler sonography showed that the involved areas of the pancreas had increased color flow signals, indicating that the metastatic tumor was characteristically hypervascular. In patients with a history of RCC, color or power Doppler sonographic demonstration of diffuse enlargement of the pancreas with evidence of hypervascularity may indicate metastasis of RCC to the pancreas.

Aged↗
PubMed2002

Colonic diverticulitis diagnosed by computed tomography in the ED.

The purpose of this study is to evaluate the application of computed tomography (CT) in the diagnosis of colonic diverticulitis in the emergency department (ED). Clinical information and CT images of 38 proved cases of colonic diverticulitis were reviewed retrospectively. The most common CT findings were pericolic fat infiltration (100%), thickened fascia (78.9%), muscular hypertrophy (26.3%), and arrowhead sign (23.7%). The CT findings were correlated with clinical prognosis and 3 parameters were found to be indicators for poor prognosis: older age, abscess formation, and presence of free air. The patients with diverticulitis on right side colon were found to be younger in age and the lesions were shorter in involved length with higher incidence of muscular hypertrophy and less incidence of perforation, as compared with the left side group.

Adult↗
PubMed2002

Evaluation of calcific tendonitis of the rotator cuff: role of color Doppler ultrasonography.

OBJECTIVE: To use color Doppler ultrasonography to evaluate the morphology and vascularity of calcific tendonitis and to predict the formative and resorptive phases of the calcification. METHODS: Ninety-four patients with shoulder calcification on plain radiographs were enrolled in this study. Ultrasonography of the shoulder was focused on the rotator cuff. Color Doppler ultrasonography was applied in the calcific region. Patient symptoms were graded as painless, mild, moderate, and severe. The calcific plaques were classified as arc-shaped, fragmented or punctate, nodular, and cystic types. Color Doppler ultrasonographic signals were graded 0 to 3. The formative and resorptive phases of calcification were categorized by patient symptoms; acute onset of moderate or severe pain indicated the resorptive phase. RESULTS: The calcific plaques appeared arc shaped in 59 patients (20 painless, 19 mild, and 20 moderate), fragmented or punctate in 27 (2 painless, 3 mild, 20 moderate, and 2 severe), nodular in 6 (1 moderate and 5 severe), and cystic in 2 (severe). There was a significant difference between the morphology of the calcific plaques and clinical symptoms (P < .01). On color Doppler ultrasonography, grade 0 signals were found in 28 patients (22 painless and 6 with mild pain); grade 1 in 18 (16 mild and 2 severe); grade 2 in 41 (all moderate); and grade 3 in 7 (all severe). The correspondence between color Doppler ultrasonographic findings and clinical symptoms was excellent (P < .01). CONCLUSIONS: High-resolution ultrasonography with color Doppler imaging could differentiate the formative and resorptive phases of the calcification and could be used as a follow-up modality in calcific tendonitis of the shoulder.

Calcinosis↗
PubMed2002

Hereditary hemorrhagic telangiectasia.

Hereditary hemorrhagic telangiectasia (HHT), also known as Osler-Weber-Rendu disease, is a rare disorder characterized by arteriovenous communications in visceral organs. The diagnosis of HHT consists of recurrent epistaxis, mucocutaneous telangiectasis, visceral vascular lesion and familial occurrence. HHT can be definitely diagnosed with the presence of all these three criteria. The prevalence of liver involvement of HHT was reported to range from 8 to 31%. Herein, we present a 75-year-old male who was diagnosed as having HHT with liver involvement, based on the findings of recurrent epistaxis, mucosal telangiectasis on the lower lip and hepatic arteriovenous malformation. The clinical presentations of this patient are discussed, and the literature is reviewed.

Aged↗
PubMedDate not supplied

Sonographically guided core needle biopsy of soft tissue neoplasms.

PURPOSE: This study was conducted to evaluate the usefulness of sonography (US)-guided needle biopsy in the diagnosis of soft tissue masses. PATIENTS AND METHODS: Thirty-seven patients with a mean age of 49 years were enrolled in the study. The size of the biopsy needle was selected according to the kind of tumor suspected (ie, primary or metastatic). In patients with suspected metastases, smaller biopsy needles were used; in patients with suspected primary tumors, larger needles were used so that larger specimens could be obtained. Prebiopsy color Doppler sonography (CDUS) was routinely used to guide the cutting needle to areas of the lesion showing sufficient vascularity. From 3 to 6 cores were obtained, depending on their quality. We compared the diagnoses yielded by the core biopsy and the final histopathologic analysis of the resected tumor by classifying the results as "concordant" or "discordant." RESULTS: A total of 37 tumors were examined. Final diagnoses were 24 malignant tumors (6 metastases and 18 primary tumors) and 13 benign tumors. The lesions were diagnosed correctly as either benign or malignant in 35 of the 36 cases for which needle biopsy specimens were adequate, with only 1 misdiagnosis. The diagnoses were concordant in 33 cases (17 primary malignant tumors, 6 metastatic tumors, and 10 benign tumors) and were discordant diagnosis in the other 4 cases (1 primary malignant tumor and 3 benign tumors). No complications were attributable to the needle biopsy. CONCLUSIONS: US-guided percutaneous core needle biopsy of soft tissue neoplasms is an easy, safe, and useful procedure. It can be considered a first-line procedure for the acquisition of tissue specimens adequate for histopathologic diagnosis.

Adolescent↗
PubMedDate not supplied

Epiploic appendagitis of the rectosigmoid junction: demonstration with transrectal sonography.

A 24-year-old man presented with lower abdominal pain that had been present for 18 hours. Physical examination revealed mild tenderness in the lower abdomen. Digital rectal examination revealed a tender point approximately 9 cm above the anal verge. Transrectal sonographic examination demonstrated an ovoid echogenic noncompressible mass surrounded by a hypoechoic halo attached to the wall of the rectosigmoid junction. A diagnosis of epiploic appendagitis was made on the basis of sonographic findings and was subsequently confirmed with contrast-enhanced CT.

Abdominal Pain↗
PubMedDate not supplied

Gray-scale and color Doppler ultrasonographic manifestations of papillary thyroid carcinoma: analysis of 51 cases.

UNLABELLED: The purpose of this study is to assess the specific ultrasonic characteristics of papillary thyroid carcinoma and to determine the relative frequency of various patterns of papillary carcinoma on gray-scale ultrasonography (US) and color Doppler ultrasonography (CDU). METHODS: We retrospectively reviewed US features in 51 patients with confirmed papillary thyroid carcinoma. The features were analyzed based on tumor size, echogenicity, echotexture, boundary, margin, shape, and calcification pattern on gray-scale US imaging, and on patterns of vascularity on CDU. We obtained the relative frequency of features and classified these features into three categories: common (> or =50% of lesions), less common (>10% but <50%), and uncommon (< or =10%). Individual differences and combinations of features were also analyzed. RESULTS: In total, 67 nodules were enrolled in our study. The sizes of 76% of nodular lesions were <20.0 mm. Common US features of papillary carcinoma included: a homogeneous hypoechoic solid picture; a poorly defined boundary; an irregular margin; the absence of halo; the absence of calcifications or microcalcifications; and mixed perinodular and intranodular blood flow patterns. Less common features included: a heterogeneous hypoechoic or very hypoechoic picture; microcalcifications; a well-defined boundary; a regular margin; a halo with uneven thickness or an incomplete halo; and a taller-than-wide shape. Uncommon features included: an isoechoic picture; solid with cystic components; coarse calcifications; mixed coarse calcifications and microcalcifications; "inferno"-type blood flow; and absence of blood flow. On average, each nodule had 4.9 US features considered common, 1.8 US features considered less common, and 0.4 US feature considered uncommon. Features such as predominantly cystic composition, hyperechoic texture, and hypoechoic halo with even thickness were never found in our study. The top two common manifestations of papillary carcinoma were solid architecture and mixed perinodular and intranodular blood flow signals. CONCLUSION: All lesions in our series had a predominantly solid characteristic on gray-scale US.

Adult↗
PubMedDate not supplied

Peritendinous lesions: the role of high-resolution ultrasonography.

PURPOSE: To evaluate the peritendinous lesions over the extremities by high-resolution ultrasonography (HRUS). MATERIALS AND METHODS: The authors retrospectively collected 328 cases, focusing on peritendinous lesions in limbs. The diagnosis was made by US findings with long-term follow-up, aspiration and biopsy proved. RESULTS: The most common disease entity in our study is ganglion (n=270), followed by Baker's cyst (n=24). Other disease entities included tenosynovitis, bursitis, gout, hematoma, amyloidosis, thrombophlebitis, and other tumor/tumor-like lesions, such as osteogenic sarcoma (OGS), schwannoma, lymphoma, myxoid lipomsarcoma, xanthoma, intramuscular cavernous hemangioma, pigmented villonodular synovitis (PVNS), giant cell tumor of the tendon sheath (GCTTS), etc. CONCLUSION: Because of dynamic capabilities and aid of real-time sono-guided fine needle aspiration, HRUS becomes an efficient and inexpensive tool for musculoskeletal lesions, especially in the superficial parts.

Adult↗
PubMedDate not supplied

Six surgery-correlated sonographic signs for rotator cuff tears: emphasis on partial-thickness tear.

The purpose of the study is to correlate the sonographic signs of rotator cuff tears (RCTs) with surgical findings, with emphasis on partial-thickness tear. We prospectively performed ultrasonography (US) on 50 patients with suspected RCTs and comparison with operative findings. Six US signs, which included "nonvisualization", "focal depression", "focal thinning", "focal hypoechoic cleft", "floating bright spots" and "focal heterogeneous hypoechogenicity" in rotator cuffs (RCs), were emphasized, but only "focal heterogeneous hypoechogenicity" favored partial-thickness tear (10/14, 71%). All the other five signs, including "floating bright spots" (not pointed out in literatures), were suggestive of full-thickness tear. The overall sensitivity, specificity, positive predictive value, negative predictive value and accuracy for US to detect RCTs were 95%, 90%, 97%, 82% and 94%, respectively. US is effective to detect RCTs and differentiate full- from partial-thickness tear.

Adolescent↗
PubMedDate not supplied

Interventional procedures in superficial lesions: the value of 2D with additional coronal reformatted 4D ultrasonography guidance.

OBJECTIVE: We wanted to assess the usefulness of four-dimensional (4D) ultrasonography (US), i.e., real-time three-dimensional US, as an adjunct for performing various US-guided interventional procedures in superficial lesions. MATERIALS AND METHODS: Thirty-three patients were referred for US-guided interventional procedures for superficial lesions, including core biopsy in 19, fine-needle aspiration in eight, therapeutic drug injection in four and needle puncture in two. The procedures were performed under 4D US guidance. We reviewed the pathologic/cytologic results of the core biopsies or needle aspirations, and also the outcomes of drug injection or needle puncture. RESULTS: For all the patients who underwent 4D US-guided core biopsy, the specimens were adequate for making the pathological diagnosis, and specimens were successfully obtained for those patients who underwent 4D US-guided aspiration. The patients treated with 4D US-guided therapeutic drug injection or needle puncture had a good response. No major procedure-related complications occurred. The procedural times were similar to those procedural times with using two-dimensional US. CONCLUSION: Combining the two dimensional and 4D US techniques aids the physician when performing US-guided interventional procedures for the superficial lesions.

Adolescent↗
PubMedDate not supplied

Syndrome of mitochondrial myopathy of the heart and skeletal muscle, congenital cataract and lactic acidosis.

The syndrome of hypertrophic cardiomyopathy, mitochondrial myopathy, congenital cataract, and lactic acidosis is a rare disease. It is now considered as an autosomal recessive inheritance. Two forms of the syndrome can be identified, the neonatal fatal and the benign adult variants. We report on 2 cases from a family and compared their clinical and histopathological features with 23 other patients previously reported in the literature. Detailed histochemical and ultrastructural findings of these two patients are outlined in the text. Histopathological features revealed abnormal mitochondrial proliferation in the heart and skeletal muscles. Tissue staining showed the activities of several enzymes of the mitochondrial respiratory chain to be within normal range. Despite severe lactic acidemia, no defect was found in the rate of pyruvate oxidation among these patients.

Cataract↗