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Chui-Mei Tiu

Publications and source records attributed to Chui-Mei Tiu.

At least 19 recordsLinked to original sources
PubMed2007

Primary small cell carcinoma of the pancreas with an unusual sonographic appearance.

We present a case of primary pancreatic small cell carcinoma with an unusual sonographic feature. A 75-year-old woman presented with poor appetite and weight loss. Abdominal sonographic examination revealed a diffusely enlarged pancreas with relative increased echogenicity and smooth contour. CT also confirmed the diffuse infiltrative pattern of the tumor. The diagnosis was confirmed via sonographically guided biopsy. The tumor was composed of small cells with hyperchromatic nuclei and scanty cytoplasm infiltrating the pancreatic tissue, consistent with small cell carcinoma of the pancreas. Primary pancreatic small cell carcinoma rarely presents as the diffuse infiltrating type. These unusual sonographic features must be differentiated from other pancreatic tumors presenting as diffuse pancreatic enlargement.

Aged↗
PubMed2006

Biweekly oxaliplatin plus 1-day infusional fluorouracil/leucovorin followed by metronomic chemotherapy with tegafur/uracil in pretreated metastatic colorectal cancer.

PURPOSE: Metronomic chemotherapy, at a minimally toxic dose and with a frequent schedule, is a potentially novel approach to the control of advanced cancer disease via a different mechanism from maximum tolerable doses chemotherapy. Taking advantage of the potential effectiveness of metronomic therapy, tegafur/uracil (UFT) was incorporated into an oxaliplation/infusioanl fluouracil (5-FU)/leucovorin (LV) protocol in this study. The primary endpoints were response rate, time to progression (TTP) and safety profile in 5-FU-pretreated metastatic colorectal cancers (CRCs). PATIENTS AND METHODS: Twenty-eight patients with metastatic CRCs resistant or refractory to 5-FU/LV were enrolled. Chemotherapy was administrated every 2 weeks sequentially with 2-h infusion of oxaliplatin (85 mg/m2) and LV (200 mg/m2), intravenous bolus 5-FU (400 mg/m2), 22-h infusion of 5-FU (600 mg/m2) on day 1 and then followed by 10-day daily oral UFT (200 mg/m2)/LV (30 mg/m2). RESULTS: Partial response was seen in ten (35.7%) patients. The median TTP was 5.2 (95% CI: 4.16-6.31) months and the median overall survival was 13.4 (95% CI: 6.39-20.5) months. No grade 3 toxicities above 5% according to National Cancer Institute-Common Toxicity Criteria (NCI-CTC) occurred except sensory neuropathy (10.7%). No grade 4 toxicity, treatment-related mortality or hand-foot syndrome was found. CONCLUSIONS: This study protocol with favorable toxicity profile is thus promisingly effective against 5-FU-pretreated metastatic CRCs. Given the present experience, an evaluation of the regimen as front-line treatment of metastatic CRC is planned.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2006

Sonographic features of nonpalpable breast cancer: a study based on ultrasound-guided wire-localized surgical biopsies.

The purpose of this study is to investigate the correlation between surgicopathological findings and ultrasonic images of nonpalpable breast lesions. The study was composed of 220 nonpalpable breast lesions from 193 patients. The breast lesions were classified into soft tissue type (185 lesions) and calcification type (35 lesions). Of the 220 lesions, 62 (28%) were malignant. For soft tissue type lesions, the sonographic features of sound attenuation (p < 0.001) and irregular border (p < 0.001) were significantly associated with the malignant diagnosis. For soft tissue-type and calcification-type lesions, the presence of increased vascularity (p < 0.001) or calcification (p < 0.001) was significantly associated with the malignant diagnosis. Of the 164 breast lesions with corresponding mammograms, 37 of 74 mammographically identifiable lesions were pathologically malignant, as compared with 16 of 90 lesions with negative mammograms (p < 0.001). In our study, the more sensitive sonographic features for predicting malignancy were irregular border and increased vascularity (sensitivity 88% and 82%, respectively), whereas the features of sound attenuation and presence of calcifications were more specific (specificity 88% and 80%, respectively). In conclusion, ultrasound-guided wire localization of breast lesions is not only useful in assisting surgical biopsy, but the sonographic findings obtained by this procedure correlate with pathologic diagnosis.

Adolescent↗
PubMed2005

Is urorectal septum malformation sequence a variant of the vertebral defects, anal atresia, tracheo-oesophageal fistula, renal defects and radial dysplasia association? Report of a case and a review of the literature.

UNLABELLED: The urorectal septum malformation sequence (URSMS) consists of multiple systems anomalies including ambiguous genitalia, the absence of a perineal opening, an imperforate anus, and urogenital, colonic and lumbosacral anomalies. We describe a 3-day-old female infant with characteristic URSMS and review its clinical manifestations, outcomes and putative pathogenesis. We also compare its characteristics with those of the vertebral defects, anal atresia, tracheo-oesophageal fistula, renal defects and radial dysplasia (VATER) association. CONCLUSION: Although defects of the urorectal septum malformation sequence and the vertebral defects, anal atresia, tracheo-oesophageal fistula, renal defects and radial dysplasia association overlap, we believe that they are separate entities. Differentiating the urorectal septum malformation sequence from vertebral defects, anal atresia, tracheo-oesophageal fistula, renal defects and radial dysplasia association is helpful to develop appropriate clinical investigations and search for the aetiology and pathogenesis of these diseases.

Abnormalities, Multiple↗
PubMed2005

Can ruptured appendicitis be detected preoperatively in the ED?

PURPOSE: The purpose of this study is to determine which clinical symptoms/signs and computed tomography (CT) signs can help in distinguishing ruptured from simple appendicitis. MATERIALS AND METHODS: The medical records and CT findings of 202 consecutive patients with surgically proven acute appendicitis were retrospectively reviewed and compared between 2 groups with and without appendiceal rupture. RESULTS: Longer duration of symptoms ( P < .001), peritoneal sign ( P = .004), and higher C-reactive protein ( P < .001) are significant clinical factors for predicting appendiceal rupture in acute appendicitis. Abscess, extraluminal air, wall defect, peritoneal enhancement, extraluminal appendolith, phlegmon, localized fluid, fascial thickening, ascites, stool impaction, and 4 patterns of bowel wall thickening ( P < .001 to P = .047) are significant CT signs for predicting appendiceal rupture. The appendiceal diameter is larger in patients with ruptured appendicitis than in those with simple appendicitis (13.2 +/- 3.2 vs 11.3 +/- 2.4 mm, P < .001). The appendolith size is larger in patients with ruptured appendicitis than in those with simple appendicitis (7.1 +/- 4.4 vs 5.1 +/- 2.8 mm, P = .018). CONCLUSION: Besides some clinical findings, CT scan can accurately determine appendiceal rupture in acute appendicitis and can further demonstrate the presence of local inflammatory mass, facilitating management decision in the emergency department (ED).

Adolescent↗
PubMed2005

Differentiating colonic diverticulitis from colon cancer: the value of computed tomography in the emergency setting.

BACKGROUND: The purpose of this study was to establish practical diagnostic criteria to differentiate colonic diverticulitis from colon cancer by computed tomography (CT) in the emergency department (ER). METHODS: Helical CT scans of 40 patients admitted to the ER with the clinical diagnosis of diverticulitis and 14 patients diagnosed with colon cancer were retrospectively reviewed. In total, 18 imaging parameters were analyzed and were compared between the 2 groups of patients. RESULTS: Thirteen parameters were found to be statistically significant for the diagnosis of colonic diverticulitis in excluding colon cancer: pericolic infiltration (p < 0.001); presence of lymph nodes (p < 0.001); inflamed diverticula (p = 0.001); non-inflamed diverticula (p = 0.001); degree of enhancement (p = 0.001); intestinal obstruction (p = 0.001); involved wall thickness (p = 0.005); lymph node size (p = 0.007); fascial thickening (p = 0.009); pattern of enhancement (p = 0.012); involved length (p = 0.014); free air (p = 0.035); and abscess formation (p = 0.042). Among these parameters, the most valuable imaging findings for diverticulitis were the presence of non-inflamed diverticulum, inflamed diverticulum, mild degree of enhancement, and small lymph node size. Three were found to have high specificity but low sensitivity: target enhancement pattern; abscess formation; and free air. When colonic obstruction is present, colon cancer is more likely than diverticulitis. CONCLUSION: Specific CT criteria help to differentiate colonic diverticulitis from colon cancer. CT scan with intravenous contrast administration would be the best noninvasive imaging modality in the ER for the accurate diagnosis and appropriate management of such disease.

Adult↗
PubMed2004

Xanthogranulomatous pyelonephritis treated by partial nephrectomy.

Xanthogranulomatous pyelonephritis is an uncommon disease in children. We report of a 2-month-old girl with urinary tract infection and with a renal mass detected by ultrasound scan. The preoperative differential diagnoses were Wilms tumor, multicystic dysplastic kidney, renal abscess, and mesoplastic nephroma. The subsequent histopathological findings allowed the diagnosis of xanthogranulomatous pyelonephritis (XGP). Although XGP is rare at this age, it must be considered in the differential diagnosis of a child presenting with renal mass, either with or without associated urolithiasis, anemia, and elevated inflammatory markers. The long-standing mainstay of therapy for diffuse XGP has been nephrectomy. However, we report the successful preservation of renal mass with partial nephrectomy for diffuse XGP. The affected kidney grew normally and preserved residual function after the operation. Hence we strongly suggest parenchymal saving in pediatric cases of XGP to preserve renal function.

Antihypertensive Agents↗
PubMed2004

Splenic hamartoma: presentation on contrast-enhanced sonography.

Splenic hamartoma is a rare benign tumor of the spleen. It is usually found incidentally at autopsy or splenectomy. We report a case of splenic hamartoma that was discovered during medical workup for vague upper abdominal pain. Abdominal sonography demonstrated a well-demarcated, slightly hypoechoic splenic solid mass; the mass was markedly enhanced on color Doppler sonography after injection of microbubble contrast agent. This finding may help to distinguish splenic hamartomas from other relatively common splenic tumors, such as hemangiomas or metastases.

Contrast Media↗
PubMed2004

Computed tomography features of acute pulmonary tuberculosis.

The purpose of this study was to demonstrate the computed tomography (CT) features of pulmonary tuberculosis in patients with acute clinical manifestations. The emergent CT images of 46 non-AIDS patients with acute clinical presentations of pulmonary tuberculosis (TB) were analyzed. The distribution and characterization of the pulmonary and pleural lesions were specifically focused. Multifocal airspace consolidation in multiple lobes was most commonly seen on the CT in 32 of 46 patients (70%), followed by cavitary pulmonary nodular shadows (50%). Other CT manifestations included pleural effusion (40%), TB empyema (20%), and lymphadenopathy (11%). On followup, 12 patients (26%) developed acute respiratory failure. Patients presenting with multifocal pulmonary consolidation, with or without cavitations, on CT should undergo early pulmonary TB workup. These findings could help early detection for pulmonary TB.

Acute Disease↗
PubMed2004

Factor analysis in both spatial and temporal domains of color blooming artifacts in ultrasound investigations utilizing contrast agents.

Color blooming artifacts can cause misinterpretations of normal and pathological structures during color Doppler flow imaging with ultrasound contrast agents (USCAs). These artifacts are characterized in both the spatial and temporal domains: in the spatial domain, artifacts result from wave propagation and the ultrasound system; and in the temporal domain, the color blooming time (CBT) is used to denote the duration of artifacts. In our experiments, CBT decreased from 86.7 to 46.8 s when the transmitting pressure was decreased from 370 to 180 kPa. From this, we conclude that an adaptive mechanical index can significantly shorten the CBT, which may in turn prolong the optimal viewing time during in vivo ultrasound investigations utilizing USCAs.

Artifacts↗
PubMed2004

Prostatic abscess: transrectal color Doppler ultrasonic diagnosis and minimally invasive therapeutic management.

The purpose of this study was to analyze the transrectal ultrasound (US), or TRUS, and color Doppler ultrasonography (CDU) findings and therapeutic strategies with TRUS-guided procedures in 13 patients with prostatic abscess. Over a period of 6 years, 18 prostatic abscesses were diagnosed in 13 patients (mean age: 59 years). Diagnostic workup included TRUS, analysis of midstream urine, and analysis and culture of abscess fluid for leukocytes and pathogens. These patients were treated either conservatively (for abscess cavities < 1 cm in diameter), or by aspiration or draining procedures (cavities > or = 1 cm). The transrectal CDU findings were correlated to the treatment effects. The predisposing factors were also reviewed. In the 13 patients, the most common clinical symptom and sign were urinary frequency (77%) and pus cell in the midstream urine (92%). Predisposing factors were found in 11 men, with diabetes in 5 of them. In 10 patients, the definitive preinterventional diagnosis was based on the TRUS findings. TRUS with probe palpation demonstrated tiny floating echogenic speckles in the abscess cavity in 4 patients. CDU demonstrated increased color-flow signals at the margin and surrounding tissue of the abscess pockets. Abscesses with poorly defined boundaries had more prominent surrounding color-flow signals and achieved, with relative difficulty, a satisfactory aspiration procedure. Aspiration was done for all 11 abscesses between 1 and 3 cm. A total of 4 larger abscesses (> 3.0 cm) were treated with aspiration or drainage using a 5-French pigtail catheter. No surgical drainage was performed. Transrectal CDU may help in the evaluation of maturity of an abscess pocket. US-guided aspiration with an 18-gauge needle or drainage with a 5-French pigtail catheter significantly shortened the hospital stay.

Abscess↗
PubMed2004

Tuberculosis of the parotid gland: sonographic manifestations and sonographically guided aspiration.

OBJECTIVE: Involvement of the parotid gland by tuberculosis (TB) is rare. If treated properly, the prognosis of TB of the parotid gland is good. In this retrospective study, we report our experience with sonography and sonographically guided aspiration in the diagnosis of parotid TB. METHODS: Over 12 years, 9 adults (mean age, 48 years) with parotid gland TB had been examined with high-resolution sonography and color Doppler sonography for their clinical problems of swelling on the mandibular angle. Sonographically guided fine-needle aspiration was done for cytologic study, stains for acid-fast bacilli, and cultures for mycobacterium. RESULTS: The sonographic patterns were classified as chiefly the parenchymal type (4 patients) and chiefly the periparotid type (5 patients). The parenchymal type appeared as a diffusely enlarged, comparatively hypoechoic gland (compared with the contralateral asymptomatic gland), with or without focal intraparotid nearly anechoic zones, which might have a cavity or cavities within it. The periparotid type appeared as hypoechoic nodules located in the peripheral zone of the hyperechoic parotid gland, consistent with enlarged periglandular lymph nodes. The diagnosis of parotid TB was made in 8 of 9 patients on the basis of sonographically guided aspiration for acid-fast bacilli stains, cytologic study, and cultures for mycobacterium. CONCLUSIONS: Sonographic examination contributes substantially in the diagnosis of parotid TB infection. In the presence of diffuse parotid echo pattern changes with periparotid lymphadenopathy, and with or without focal hypoechoic zones, TB infection should be differentiated. Sonographically guided fine-needle aspiration may provide further diagnostic information by means of stains, cultures, and cytologic study.

Adult↗
PubMed2004

Significance of pulmonary venous obstruction in total anomalous pulmonary venous return.

BACKGROUND: Total anomalous pulmonary venous return (TAPVR) is an uncommon congenital cardiovascular anomaly with poor natural prognosis. It has been detected more frequently in recent year due to the advent of echocardiography and cardiovascular magnetic resonance imaging (MRI). The aim of this study was to evaluate the clinical manifestations and outcomes in TAPVR patients with or without pulmonary venous obstruction (PVO). METHODS: From January 1985 to December 2002, a total of 27 cases with TAPVR at our institution were reviewed. Accurding to the preseace or assence of PVO, patients were divided into PVO group and non-PVO group. Patients' sex, age at diagnosis, types of TAPVR, clinical manifestations, surgical treatment and outcomes were evaluated. RESULTS: All of them had received 2-dimensional (2-D) and color Doppler echocardiography examination. Cardiac catheterization was performed in all but 1 patient who died at the first day of birth. In addition, 10 of 27 cases had cardiovascular MRI for further study. The number of cases in PVO group and non-PVO group were 15 (56%) and 12 (44%), respectively. There was no significant difference in sex or pulmonary venous drainage sites between both groups. Cyanosis was more prevalent in the PVO group (80% vs. 30%, p = 0.038). Four (27%) cases PVO group and 3 (25%) cases of the non-PVO group had of the non-isolated cardiac lesions. Pulmonary hypertension was present in 18 (69%) of 26 cases who had received cardiac catheterization. Among them, 10 had PVO and 5 had systemic level of pulmonary arterial pressure. Seven (30%) of 23 patients who had received operation died; in contrast, 3 of 4 patients without operation expired. The remaining 1 did not had surgery because of complex heart disease. There was no significant difference in surgical mortality between PVO and non-PVO groups (33% vs. 27%). CONCLUSIONS: Cyanosis is an obvious clinical symptom of obstructed TAPVR. Surgical mortality made no significant difference between obstructed and non-obstructed groups. Early detection and surgical treatment for TAPVR are important. Although cardiac catheterization and angiocardiography is the golden standard for the diagnosis, 2-D and color Doppler echocardiography can also provide quick and accurate diagnostic images of TAPVR.

Child, Preschool↗
PubMed2003

Congenital pelvic arteriovenous malformation: two cases and MR findings.

Congenital pelvic arteriovenous malformation (PAVM) is rare. We present two cases with emphasis on the imaging features. Magnetic resonance angiography (MRA) demonstrates comparable details of the vascular abnormalities as conventional angiography, which should be reserved for pre-embolization evaluation.

Adult↗
PubMed2003

Imaging studies of pyriform sinus fistula.

BACKGROUND: Pyriform sinus fistula (PSF) refers to a persistent embryologic third or fourth pharyngeal pouch, which typically presents as a congenital sinus tract that originates from the pyriform sinus. The sinus tract is often diagnosed by a barium study or direct endoscopic inspection. Utilization of advanced imaging studies, including ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI), may aid in the diagnosis of this disease entity. OBJECTIVES: To review the imaging findings of PSF and demonstrate the value of various cross-sectional imaging (US, CT, and MRI) in the diagnosis of PSF. MATERIALS AND METHODS: PSF in five children was verified surgically. Preoperative barium esophagography, US, CT, and MRI were performed selectively in these patients. The clinical and imaging findings are reviewed retrospectively. RESULTS: Barium studies demonstrated the sinus tract in all five patients. US, CT, and MRI demonstrated an associated inflammatory process. By utilizing the trumpet maneuver, the presence of sinus tract was evident in two patients during US. The sinus tract is also demonstrated by CT in another patient. CONCLUSIONS: Although barium esophagography is advantageous in demonstration of the sinus tract in PSF, US and CT are also capable of showing the sinus tract. The extent of inflammatory process related to PSF is better delineated by US, CT, and MRI.

Adolescent↗