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Wong YY, Chu WCW, Lam WWM. Intravenous leiomyomatosis: computed tomography diagnosis. Hong Kong Med J 2006; 12:239-40. [PMID: 16760557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023] Open
Abstract
Intravenous leiomyomatosis is a rare neoplastic condition characterised by nodular masses of histologically benign smooth muscle growing within veins. In most cases, the disease is confined to the pelvic veins, but involvement may extend to the inferior vena cava and right heart chamber. We report the computed tomography features of a woman who developed extensive intravenous leiomyomatosis and lung metastases, and presented with acute-onset lower limb swelling.
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Tse GMK, Tan PH, Lui PCW, Gilks CB, Poon CSP, Ma TKF, Law BKB, Lam WWM. The role of immunohistochemistry for smooth-muscle actin, p63, CD10 and cytokeratin 14 in the differential diagnosis of papillary lesions of the breast. J Clin Pathol 2006; 60:315-20. [PMID: 16698948 PMCID: PMC1860581 DOI: 10.1136/jcp.2006.036830] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Histological differentiation of mammary papillary lesions can be difficult. The evaluation of myoepithelial cells can be helpful, with benign papilloma showing a continuous myoepithelial cell layer, which becomes attenuated or absent in malignant papillary lesions. METHODS A large series of 100 papillomas (28 papillomas with florid epithelial hyperplasia) and 68 papillary carcinomas (9 invasive, 44 in situ, and 15 ductal carcinomas in situ (DCIS) involving papillomas) of the breast were stained for myoepithelial cells by immunohistochemistry using antibodies to smooth-muscle actin (SMA), p63, CD10 and cytokeratin (CK) 14. RESULTS In the papillomas, using these four antibodies, myoepithelial cells were positive in 88%, 99%, 91% and 95% of cases, respectively, with SMA showing marked stromal component cell staining and CD10 showing epithelial and stromal staining. CK14 also showed epithelial staining in 71% of papillomas and 96% of papillomas with florid epithelial hyperplasia. In the papillary carcinomas, 36 (53%) cases showed staining of myoepithelial cells that were scattered, discontinuous and diminished in number and the remaining 32 (47%) cases did not show myoepithelial cells. Invasive papillary carcinoma has the lowest proportion (33%) with myoepithelial cells, and DCIS involving papillomas had the highest proportion (87%). CONCLUSIONS p63 had the highest sensitivity and did not cross-react with stromal cells and only rarely with epithelial cells. CK14 has the added ability to distinguish between florid epithelial hyperplasia involving papilloma and DCIS involving papillomas. CK14 and p63 may be used as an adjunct in assessing difficult papillary lesions of the breast.
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MESH Headings
- Actins/metabolism
- Adult
- Aged
- Aged, 80 and over
- Biomarkers, Tumor/metabolism
- Breast Neoplasms/metabolism
- Breast Neoplasms/pathology
- Carcinoma, Intraductal, Noninfiltrating/metabolism
- Carcinoma, Intraductal, Noninfiltrating/pathology
- Carcinoma, Papillary/metabolism
- Carcinoma, Papillary/pathology
- DNA-Binding Proteins/metabolism
- Diagnosis, Differential
- Female
- Humans
- Keratin-14/metabolism
- Middle Aged
- Neoplasm Proteins/metabolism
- Neprilysin/metabolism
- Papilloma/metabolism
- Papilloma/pathology
- Papilloma, Intraductal/metabolism
- Papilloma, Intraductal/pathology
- Trans-Activators/metabolism
- Transcription Factors
- Tumor Suppressor Proteins/metabolism
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Chen XY, Lam WWM, Ng HK, Fan YH, Wong KS. The Frequency and Determinants of Calcification in Intracranial Arteries in Chinese Patients Who Underwent Computed Tomography Examinations. Cerebrovasc Dis 2006; 21:91-7. [PMID: 16340183 DOI: 10.1159/000090206] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2005] [Accepted: 07/22/2005] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Intracranial artery calcification is common but the prevalence and determinants are not well established. We aim to describe the prevalence and location of calcification in intracranial arteries according to brain multi-detector-row computed tomography (MDCT) images, and to investigate its correlation with potential risk factors. METHODS We studied consecutive men and women referred for brain CT in December 2004. All patients received a questionnaire regarding their medical history related to atherosclerosis, including traditional risk factors of atherosclerosis, serum chemistry values and inflammatory markers. All CT examinations were done with a 16-slice MDCT and the severity of intracranial artery calcification was categorized. RESULTS Four hundred and ninety patients aged 1.4-101 years (62.92+/-19.04; mean+/-SD) were included in our study. There were 340 patients (69.4%) who had intracranial artery calcification. The highest prevalence of intracranial artery calcification was seen in the internal carotid artery (60%), followed by vertebral artery (20%), middle cerebral artery (5%) and basilar artery (5%). Patients with calcification were significantly older than those without calcification (p<0.001). A significantly higher prevalence of calcification was present among patients with hypertension (p<0.001), diabetes (p<0.001), renal failure (p<0.05), atrial fibrillation (p<0.05), smoking (p<0.05), hyperlipidemia (p<0.001), ischemic heart disease (p<0.05) and ischemic stroke (p<0.001). Mean values of serum phosphate, serum urea and CRP level were also significantly higher in patients with intracranial artery calcification (p<0.05, respectively), and there was a trend that patients with intracranial calcification had a higher white blood cell count (p=0.070). Stepwise multiple logistic regression showed age (RR=2.795 per 10 years), a history of ischemic stroke (RR=3.915), and white blood cell count (RR=1.107) to be independently associated with intracranial artery calcification. CONCLUSIONS Calcification of the intracranial arteries is associated with age, history of ischemic stroke and white blood cell count. Further prospective studies to investigate the clinical significance of intracranial artery calcification are needed.
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Ho SSY, Lam WWM, Wong KS, Leung CSF, Metreweli C. Potential Value of Poststroke Extracranial Arterial Blood Flow Volume in the Prediction of Stroke Functional Outcome. Cerebrovasc Dis 2006; 21:54-9. [PMID: 16282691 DOI: 10.1159/000089595] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2005] [Accepted: 08/19/2005] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND AND PURPOSE Cerebral vasoreactivity and collateral circulation are important protective mechanisms against cerebral ischemia. Previous studies suggest that the efficiency of these mechanisms can be reflected by extracranial arterial blood flow volume. Brain damage leading to neurological impairments can influence patients' functional recovery after stroke. This study attempted to explore the potential value of post stroke extracranial arterial blood flow volume in the prediction of stroke patients' functional outcome. METHODS We prospectively studied 362 consecutive patients who were hospitalized for recent acute strokes. All patients underwent extracranial arterial blood flow volume measurement of the carotid and vertebral arteries by color velocity imaging quantification within 3 days after admission. Their functional recovery was assessed 6 months after stroke. The effect of post stroke extracranial arterial blood flow volume on patients' functional outcome was tested by multivariate ordinal regression after controlling for other independent variables. Significance was at p<0.05. RESULTS Post stroke extracranial arterial blood flow volume together with age, pre-stroke modified Rankin scale, the National Institutes of Health Stroke Scale and diabetes mellitus had significant effects on the patients' 6-month functional outcome as measured by the modified Rankin scale after controlling for other independent variables (p<0.05). CONCLUSIONS Post stroke extracranial arterial blood flow volume is an independent outcome predictor. The graded predictive power of this parameter is potentially more superior than other outcome predictors by allowing classification of stroke outcome according to the degree of severity. A large prospective study is thus warranted to investigate its clinical value in the management of stroke patients.
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Chu WCW, Yeung HY, Chau WW, Lam WWM, Ng BKW, Lam TP, Lee KM, Cheng JCY. Changes in vertebral neural arch morphometry and functional tethering of spinal cord in adolescent idiopathic scoliosis--study with multi-planar reformat magnetic resonance imaging. Stud Health Technol Inform 2006; 123:27-33. [PMID: 17108399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
With the use of multiplanar reformat Magnetic Resonance imaging, AIS patients were found to have significantly reduced pedicle widths on concavity. Pattern of vertebral asymmetry was also exaggerated with smaller pedicle width, length and area on concavity. The cord appeared more roundish and was deviated to the concavity at apical vertebra in AIS. A tethering force might therefore be present on the cord along the transverse axis in AIS, accounted by the relatively fixed position of the exit nerve roots and deviation of the cord from the exit foraminae of the corresponding vertebra.
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Chu WCW, Lam WWM, Chan YL, Ng BKW, Lam TP, Lee KM, Guo X, Cheng JCY. Relative shortening and functional tethering of spinal cord in adolescent idiopathic scoliosis?: study with multiplanar reformat magnetic resonance imaging and somatosensory evoked potential. Spine (Phila Pa 1976) 2006; 31:E19-25. [PMID: 16395162 DOI: 10.1097/01.brs.0000193892.20764.51] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN MR imaging and multiplanar reconstruction were used to evaluate relative length of the spinal cord to the vertebral column in adolescent idiopathic scoliosis (AIS). OBJECTIVES Ratio of spinal cord length to vertebral column length and position of the cerebellar tonsils were evaluated and correlated with somatosensory cortical evoked potentials (SSEP). SUMMARY OF BACKGROUND DATA Tonsillar herniation, abnormal anthropometric growth, relative spinal overgrowth, and abnormal somatosensory function have been reported in AIS. All these observations suggest a possible neural origin of the etiopathogenesis of AIS, which can be linked to a disproportional growth between spinal column and cord. METHODS Two-dimensional sagittal MRI of the spine was performed in 28 AIS patients (14 mild curve; 14 severe curve) and 14 age-matched controls. Measurements of spinal cord, vertebral column length, and tonsillar position were made on reformat images and correlated with SSEP studies. RESULTS No significant differences in the absolute spinal cord length were found. However, there was significant relative segmental lengthening of the spinal column at the thoracic level in AIS patients with severe curve; hence, ratios of cord to vertebral column length were significantly reduced (P < 0.01). There was high interobserver reliability (0.9); 28% (8 of 28) scoliosis patients had low-lying cerebellar tonsils and abnormal SSEP, respectively. CONCLUSION There was significantly reduced spinal cord to vertebral column ratios in the AIS patients with severe curve, suggesting a disproportional growth between the skeletal and the neural systems. The relative shortening and functional tethering of spinal cord may play an important role in the etiopathogenesis of AIS.
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Mok V, Wong A, Tang WK, Lam WWM, Fan YH, Richards PS, Wong KT, Ahuja AT, Wong KS. Determinants of prestroke cognitive impairment in stroke associated with small vessel disease. Dement Geriatr Cogn Disord 2005; 20:225-30. [PMID: 16088138 DOI: 10.1159/000087310] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/29/2005] [Indexed: 11/19/2022] Open
Abstract
Understanding the determinants of prestroke cognitive impairment (PCI) in stroke associated with small vessel disease (SVD) may shed light on how to prevent further cognitive deterioration after stroke. We administered the Informant Questionnaire on Cognitive Decline (IQCODE) to close informants of 78 consecutive stroke patients who had SVD. PCI, as defined by an average score of IQCODE > or =3.4 was found in 19 (24%) patients. Regression analyses were performed on the following risk factors for PCI: age, years of education, gender, previous stroke, volume of white matter changes, measures of silent lacunes, cerebral atrophy index, medial temporal lobe atrophy and frontal lobe atrophy. Multivariate regression analyses revealed that only cerebral atrophy index (OR 1.5, CI 1.2-1.9, p < 0.001) predicted PCI among patients with SVD.
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Wong A, Mok V, Fan YH, Lam WWM, Liang KS, Wong KS. Hyperhomocysteinemia is associated with volumetric white matter change in patients with small vessel disease. J Neurol 2005; 253:441-7. [PMID: 16267639 DOI: 10.1007/s00415-005-0022-x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2005] [Revised: 08/03/2005] [Accepted: 08/11/2005] [Indexed: 11/26/2022]
Abstract
BACKGROUND Hyperhomocysteinemia is associated with cerebral small vessel disease (SVD). We examined the relationship between homocysteine and 1) volumetric measure of white matter change (WMC), 2) silent brain infarcts, 3) cerebral atrophy on MRI and 4) cognition on a consecutive cohort of patients with stroke associated with SVD. SUBJECTS AND METHODS Fifty-seven patients consecutively admitted to the Acute Stroke Unit in a university hospital due to stroke associated with SVD were recruited and assessed three months after the stroke. Non-fasting homocysteine was obtained. Using MRI, the number of infarcts, volume of WMC and cerebral atrophy were measured. General cognitive functions were assessed using the Mini Mental State Examination and Alzheimer's disease Assessment Scale. Mattis Dementia Rating Scale - Initiation/Perseveration subset was used to assess executive cognitive functions. RESULTS Hyperhomocysteinemia (> or = 14.88 micromol/L) significantly accounted for the volume of WMC on MRI in a multivariate stepwise regression model (adjusted R(2)=0.058, p <0.05) after adjustment for age and folate level. Patients in the highest quartile of WMC volume had significantly higher levels of homocysteine than those in lowest quartile (p <0.001). No significant relationship was found between homocysteine and silent brain infarcts, cerebral atrophy and performance on psychometric tests. CONCLUSION Hyperhomocysteinemia is associated with volumetric measure of WMC among patients with SVD. The role of homocysteine in the development of silent brain infarcts and cerebral atrophy as previously reported cannot be ascertained in this study. No direct relationship was found between homocysteine and cognitive functions.
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Chan MSM, Chu WCW, Cheung KL, Arifi AA, Lam WWM. Angiography and Dynamic Airway Evaluation with MDCT in the Diagnosis of Double Aortic Arch Associated with Tracheomalacia. AJR Am J Roentgenol 2005; 185:1248-51. [PMID: 16247144 DOI: 10.2214/ajr.04.1493] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Chu WCW, Yeung DTK, Lee KH, Lam WWM, Yeung CK. Feasibility of morphologic assessment of vascular and biliary anatomy in pediatric liver transplantation: all-in-one protocol with breath-hold magnetic resonance. J Pediatr Surg 2005; 40:1605-11. [PMID: 16226992 DOI: 10.1016/j.jpedsurg.2005.06.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND/PURPOSE Noninvasive imaging for children with liver transplantation for possible sites of vascular and biliary complication remains a challenge. The aim of this study was to investigate the feasibility of magnetic resonance (MR) imaging as a comprehensive noninvasive test for the above purpose. METHODS Thirteen children (age, 8-16 years) with biliary atresia and who received liver transplantation underwent a comprehensive MR study including MR cholangiography and gadolinium-enhanced MR angiography. Images were interpreted by 3 radiologists for liver parenchymal abnormalities; definition of hepatic arterial and venous, portal venous, and biliary anatomy; and detection of any complications. Findings were correlated with surgical records. Conventional angiography and percutaneous cholangiography were obtained for correlation in 2 patients. Confidence level scores (1-5) for depiction of anatomy were given for source, multiplanar, and 3-dimensional images. RESULTS Hepatic artery anastomosis was visualized in 12 patients (92%) and the intrahepatic arteries were demonstrated in 10 (77%). The portal, hepatic venous, and biliary anastomoses were clearly demonstrated in all patients. Stenosis of hepatic artery anastomosis and multiple biliary strictures were detected in 1 patient each and confirmed by conventional imaging. High confidence scores (higher than 4) were obtained for all kinds of MR images. CONCLUSIONS Comprehensive MR imaging can be used in long-term follow-up of pediatric liver transplant recipients for depiction of hepatic structures and possible complications.
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Zhang Y, Chan AKY, Yu CM, Yip GWK, Fung JWH, Lam WWM, So NMC, Wang M, Wu EB, Wong JT, Sanderson JE. Strain Rate Imaging Differentiates Transmural From Non-Transmural Myocardial Infarction. J Am Coll Cardiol 2005; 46:864-71. [PMID: 16139138 DOI: 10.1016/j.jacc.2005.05.054] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2004] [Revised: 05/03/2005] [Accepted: 05/10/2005] [Indexed: 11/20/2022]
Abstract
OBJECTIVES The aim of this study was to determine if strain rate imaging (SRI) correlates with the transmural extent of myocardial infarction (MI) measured by contrast-enhanced magnetic resonance imaging (Ce-MRI). BACKGROUND Identification of the transmural extent of myocardial necrosis and degree of non-viability after acute MI is clinically important. METHODS Tissue Doppler echocardiography with SRI and Ce-MRI were performed in 47 consecutive patients with a first acute MI between days 2 and 6 and compared to 60 age-matched healthy volunteers. Peak myocardial velocities and peak myocardial deformation strain rates were measured. Location and size of the infarct zone was confirmed by Ce-MRI using the delayed enhancement technique with a 16-segment model. RESULTS Contrast-enhanced MRI identified transmural infarction in 21 patients, non-transmural infarction in 15 (mean transmurality of infarct 72.3 +/- 10.6%), and another 11 patients with subendocardial infarction (<50% transmural extent of the left ventricular wall). Peak systolic strain rate (SRs) of the transmural infarction segments was significantly lower compared to normal myocardium or with non-transmural infarction segments (both p < 0.0005). A cutoff value of SRs >-0.59 s(-1) detected a transmural infarction with high sensitivity (90.9%) and high specificity (96.4%), and -0.98 s(-1) >SRs >-1.26 s(-1) distinguished subendocardial infarction from normal myocardium with a sensitivity of 81.3% and a specificity of 83.3%. CONCLUSIONS Peak myocardial deformation by SRI can differentiate transmural from non-transmural MI, and it allows noninvasive determination of transmurality of the scar after MI and thereby the extent of non-viable myocardium.
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Lui PCW, Wong RHL, Chu WCW, Lo YF, Arifi AA, Lam WWM, Chow LTC, Tse GMK. Delayed right ventricular intracavitary metastasis in a patient with Dukes B rectal adenocarcinoma. Pathology 2005; 36:592-4. [PMID: 15841701 DOI: 10.1080/00313020400011029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Mok V, Chang C, Wong A, Lam WWM, Richards PS, Wong KT, Wong KS. Neuroimaging determinants of cognitive performances in stroke associated with small vessel disease. J Neuroimaging 2005; 15:129-37. [PMID: 15746224 DOI: 10.1177/1051228404274304] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND AND PURPOSE Controversies still exist as to the neuroimaging determinants of cognitive impairment in cerebral small vessel disease (SVD). The authors studied the neuroimaging correlates of cognitive performances among patients with stroke associated with SVD. METHODS The authors per formed cerebral computed tomography, magnetic resonance imaging, and diffusion-weighted imaging among 74 consecutive patients admitted to the acute stroke unit because of stroke associated with SVD. They examined the association between cognitive performances and the following neuroimaging features: volume of white matter changes (WMC), multiplicity of lacunae, location of lacunae, total cerebral atrophy, and frontal and medial temporal lobe atrophy. RESULTS Apart from age and education, univariate linear regression analyses revealed that WMC volume, presence of thalamic lacunae, cerebral atrophy, and left frontal lobe atrophy predicted performance on the Mini-Mental State Examination while WMC volume, presence of thalamic infarcts, cerebral atrophy, and frontal lobe atrophy of both sides predicted performance on the Mattis Dementia Rating Scale-Initiation/Preservation subscale. In the multivariate analyses, education (R2=0.22, P<.001), left frontal lobe atrophy (R2=0.10, P=.004), and presence of thalamic lacunae (R2=0.04, P=.049) were found to predict performance on the Mini-Mental State Examination while age (R2=0.23, P<.001) and presence of thalamic lacunae (R2=0.08, P=.011) were found to predict performance on the Mattis Dementia Rating Scale-Initiation/Preservation. CONCLUSIONS Among patients with stroke associated with SVD, thalamic lacunae and frontal lobe atrophy are key determinants of cognitive performances.
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Chu WCW, Lam WWM, Lee KH, Yeung DKW, Sihoe J, Yeung CK. Phosphorus-31 MR Spectroscopy in Pediatric Liver Transplant Recipients: A Noninvasive Assessment of Graft Status with Correlation with Liver Function Tests and Liver Biopsy. AJR Am J Roentgenol 2005; 184:1624-9. [PMID: 15855128 DOI: 10.2214/ajr.184.5.01841624] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE Noninvasive in vivo hepatic phosphorus-31 MR spectroscopy has recently been shown to provide information about hepatic functional status. We sought to show the correlation of phosphorus-31 MR spectroscopy with blood biochemistry and liver biopsy results in pediatric patients after liver transplantation. MATERIALS AND METHODS Eleven pediatric transplant recipients (eight with good graft function, two with chronic hepatitis, and one with acute rejection) and four healthy control subjects were studied with in vivo 31P MR spectroscopy. Ratios of phosphomonoesters (PME) to total phosphorus (TP), phosphodiester (PDE) to TP, nucleotide triphosphates (NTP), inorganic phosphate (Pi), and intracellular acid-base status (pH) were measured. Liver function test (n = 11) and biopsy (n = 3) results were obtained for correlation with spectroscopic findings. RESULTS The eight patients with good graft function displayed spectral profiles similar to those of the healthy subjects, and no significant difference in the metabolic ratios of these patients compared with the control subjects was detected. Three patients with abnormal liver function and biopsy-proven hepatic complications showed elevated PME/TP ratios when compared with those of both the control subjects and the group with good graft function. CONCLUSION Phosphorus-31 MR spectroscopy is a feasible technique for the noninvasive assessment of host-related complications in pediatric patients after liver transplantation. Our preliminary data suggest that the technique may be integrated with MRI for the investigation of impaired liver function in transplant recipients when neither a biliary complication nor a vascular complication is identified.
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Ng WH, Chu WCW, Shing MK, Lam WWM, Chik KW, Li CK, Li CK, Ling SC. Role of Imaging in Management of Hemophilic Patients. AJR Am J Roentgenol 2005; 184:1619-23. [PMID: 15855127 DOI: 10.2214/ajr.184.5.01841619] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The purpose of this study was to evaluate the role of symptomatology and conventional radiographic scoring in predicting synovial hypertrophy, which could affect the clinical management of hemophilic patients. MATERIALS AND METHODS Twenty males (mean age, 14.3 years old) with hemophilic arthropathy, including 34 symptomatic joints and 26 asymptomatic joints (16 knees, 20 ankles, and 24 elbows) had conventional radiographs of individual joints obtained that were rated according to the Arnold-Hilgartner stage and the Pettersson score. The patients also underwent MRI for the detection of synovial hypertrophy. The association of synovial hypertrophy and symptomatology was evaluated using the chi-square or Fisher's exact test. The best sensitivity, specificity, and positive and negative predictive values in detection of synovial hypertrophy using symptomatology and radiographic scoring were calculated. RESULTS A significant association was seen between symptomatology and synovial hypertrophy of the knee and ankle joints (p < 0.05). The sensitivity, specificity, and positive and negative predictive values of symptomatology in detection of synovial hypertrophy of the knee were 100%, 78%, 78%, and 100%, respectively, and for the ankle were 83%, 75%, 83%, and 75%, respectively. The Arnold-Hilgartner stage and Pettersson score of the radiograph had a significant association with synovial hypertrophy of the knee and ankle joints (p < 0.05). Arnold-Hilgartner staging provided a better prediction of synovial hypertrophy, with sensitivity, specificity, positive predictive value, and negative predictive value of 100%, 100%, 100%, and 100% for knees and 82%, 100%, 100%, and 82% for ankles. CONCLUSION In hemophilic patients, the presence of symptomatology in the knee and ankle joints is associated with synovial hypertrophy, and scoring of the conventional radiographs using Arnold-Hilgartner staging is useful for the prediction of synovial hypertrophy.
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Tang APY, Chu WCW, Lam WWM, Tse GMK. Radiological appearance of postirradiation sarcoma of the chest wall after mastectomy. Clin Imaging 2005; 29:185-8. [PMID: 15855063 DOI: 10.1016/j.clinimag.2004.07.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2004] [Revised: 04/10/2004] [Indexed: 11/28/2022]
Abstract
Radiotherapy-induced sarcoma arising from the chest wall after mastectomy and irradiation is uncommon but deserves special attention due to the increasing incidence of this soft-tissue sarcoma, contributed by the early detection and employment of radiotherapy in the treatment of breast carcinoma. We report the computed tomography (CT) and magnetic resonance imaging (MRI) features of two patients who developed cutaneous high-grade sarcoma after mastectomy and irradiation for primary breast tumours more than 5 years ago.
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Tang WK, Mok V, Chan SSM, Chiu HFK, Wong KS, Kwok TCY, Lam WWM, Ungvari GS. Screening of dementia in stroke patients with lacunar infarcts: comparison of the mattis dementia rating scale and the mini-mental state examination. J Geriatr Psychiatry Neurol 2005; 18:3-7. [PMID: 15681621 DOI: 10.1177/0891988704269814] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
There have been no data on the performance of the Initiation-Perseveration subtest of the Mattis Dementia Rating Scale (MDRS-IP) in screening poststroke dementia (PSDE). Three months after the index stroke, a research assistant administered the MDRS-IP and Mini-Mental State Examination (MMSE) to 83 Chinese stroke patients with lacunar infarcts who were consecutively admitted to the stroke unit of a general hospital. A psychiatrist, who was blind to the MDRS-IP and MMSE scores, interviewed all 83 patients and made a Diagnostic and Statistical Manual of Mental Disorders (4th edition) diagnosis of dementia, which served as the benchmark for judging the performance of MDRSIP. The optimal cutoff point of MDRS-IP was 22/23. The sensitivity, specificity, and positive and negative predictive values of MDRS-IP, and the area under the receiver operating characteristic curve were 82%, 90%, 0.41, 0.98, and 0.91, respectively. The overall performance of the MDRS-IP was comparable to the MMSE.
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Lam WWM, Leung TWH, Chu WCW, Yeung DTK, Wong LKS, Poon WS. Early computed tomography features in extensive middle cerebral artery territory infarct: prediction of survival. J Neurol Neurosurg Psychiatry 2005; 76:354-7. [PMID: 15716525 PMCID: PMC1739552 DOI: 10.1136/jnnp.2003.035055] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND To assess the predictive value of prognosis of different computed tomography (CT) features and National Institutes of Health Stroke Scale score (NIHSS) in acute extensive middle cerebral artery (MCA) infarct. METHODS Fifty five patients with acute extensive MCA infarct had the CT performed within 24 hours of the onset of symptoms. A total of 11 CT features were analysed. The age distribution, presence of risk factors, presence of individual CT feature, the total CT score, and the NIHSS were correlated with the 30 day mortality. RESULTS Single explanatory variable analysis showed NIHSS, presence of midline shift, midline shift of more than 1 cm, extent of infarct, presence of hydrocephalus, effacement of subarachnoid space/cella media, attenuation of corticomedullary differentiation, and total CT score were associated with the 30 day mortality. Both extent of infarct >67% and attenuation of corticomedullary differentiation gave a sensitivity and specificity of 93% and 95%, respectively, for the prediction of survival. Logistic regression analysis showed that the extent of infarct and NIHSS were the only independent predictors. CONCLUSIONS CT features and admission NIHSS are important parameters for prediction of survival in extensive MCA infarct.
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Zhang Y, Chan AKY, Yu CM, Lam WWM, Yip GWK, Fung WH, So NMC, Wang M, Sanderson JE. Left ventricular systolic asynchrony after acute myocardial infarction in patients with narrow QRS complexes. Am Heart J 2005; 149:497-503. [PMID: 15864239 DOI: 10.1016/j.ahj.2004.05.054] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND The aim of the study was to assess the degree of left ventricular (LV) asynchrony after myocardial infarction (MI) in patients with a narrow QRS complex using tissue Doppler imaging (TDI) and correlate this with the site and extent of the infarction measured by contrast-enhanced magnetic resonance imaging (Ce-MRI). METHODS Echocardiography with TDI and Ce-MRI was performed within 6 days of acute MI in 47 patients and compared with 69 age-matched healthy volunteers. Regional myocardial velocities were assessed in 12 segments, and the corresponding systolic velocity (Sm), early diastolic velocity (Em), as well as the time to peak Sm (Ts) and time to peak Em (Te) were measured. To assess LV synchronicity, SDs of Ts (Ts-SD) and Te (Te-SD) of all 12 segments were computed. Location and size of infarct were confirmed by Ce-MRI with a 16-segment model. RESULTS All the patients had a normal QRS complex duration. The Ts-SD was significantly prolonged in the MI group when compared with controls (42.2 +/- 13.7 vs 18.0 +/- 7.0 milliseconds, P < .001). The Ts-SD was longer in patients with anterior than inferior MI (46.8 +/- 13.9 vs 34.6 +/- 8.5 milliseconds, P = .002). Stepwise multiple regression analysis revealed that infarct size was the main independent predictor of systolic asynchrony ( B = 0.79, 95% CI 0.75-1.23, P < .001). Asynchrony was not related to the transmurality of the infarction. CONCLUSIONS Myocardial infarction has a significant impact on LV synchronicity even in those with a narrow QRS complex. The degree of LV systolic asynchrony is mainly determined by the infarct size and not transmurality.
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So NMC, Lam WWM, Li D, Chan AKY, Sanderson JE, Metreweli C. Magnetic resonance coronary angiography with 3D TrueFISP: breath-hold versus respiratory gated imaging. Br J Radiol 2005; 78:116-21. [PMID: 15681322 DOI: 10.1259/bjr/66677575] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
To compare the diagnostic accuracy of coronary magnetic resonance angiography with three-dimensional (3D) trueFISP breath-hold and respiratory gated techniques for the detection of significant coronary artery stenosis. 15 patients who recently underwent elective coronary angiogram were studied and a total of 60 arteries and 48 arteries were assessed by breath-hold and respiratory gated 3D trueFISP techniques, respectively. The image quality, length of artery visualized and the presence or absence of significant coronary artery stenosis were recorded. 83.3% and 81.7% of the arteries obtained with the respiratory gated and the breath-hold techniques, respectively, had an image quality suitable for further analysis. There was no significant difference in the length of artery visualized. Sensitivity and specificity of 80%, 100% and 75% and 100%, respectively, were obtained with the breath-hold and respiratory gated techniques in detecting significant stenosis in the coronary arteries. Both techniques have moderate sensitivity and high specificity in detection of significant stenosis in the visualized segments of the major coronary arteries. However, they cannot replace conventional coronary angiogram for diagnosing coronary artery disease at present. Further studies are required to evaluate whether breath-hold approach is more efficient, therefore should be performed first and respiratory gated approach reserved for those who cannot breath-hold.
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Poon WS, Ng SCP, Chan MTV, Lam JMK, Lam WWM. Cerebral blood flow (CBF)-directed management of ventilated head-injured patients. ACTA NEUROCHIRURGICA. SUPPLEMENT 2005; 95:9-11. [PMID: 16463810 DOI: 10.1007/3-211-32318-x_2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
OBJECTIVE Ischaemic brain damage has been shown to be an important contributing factor causing head injury fatality. Maintenance of an adequate cerebral perfusion pressure is difficult in patients with elevated intracranial pressure (ICP) and deranged cerebral vasoreactivity. Thirty-five cases of ventilated moderate-to-severe head-injured patients were prospectively studied, correlating their cerebral haemodynamic abnormalities, neurochemical disturbances (using microdialysis methodology) and clinical outcome. METHODS Cerebral haemodynamic abnormalities were defined and classified by transcranial Doppler ultrasonography (TCD) and stable xenon-CT cerebral blood flow measurements (XeCT) into their status of CO2 reactivity, pressure autoregulation, hyperaemia or non-hyperaemia. Two-hour episodes of these abnormalities with and without haemodynamic intervention were followed in their changes in ICP, CPP, intracerebral metabolites and finally their clinical outcome. RESULTS Loss of CO2 reactivity was associated with a significantly higher ICP, increasing intracerebral metabolites (lactate, glutamate and glycerol) and invariably a fatal outcome. Impaired pressure autoregulation was also associated with an elevated ICP, but no significant difference in intracerebral metabolites and incidence of favourable clinical outcome. Patients with intact CO2 reactivity and impaired pressure autoregulation were treated with an elevated CPP in 32 episodes, resulting in a significant reduction in ICP, intracerebral glutamate and glycerol and non-survival. In patients with intact CO2 reactivity and impaired pressure autoregulation, eleven episodes of hyperaemia were identified by XeCT. A modest 20%, blood pressure reduction resulted in a trend towards a reduction of ICP, intracerebral glutamate and glycerol and non-survival. CONCLUSIONS The need for haemodynamic intervention in this group of ventilated patients with moderate-to-severe head inury can be made logical when these abnormalities are identified daily. The success of management was reflected by a stable or improved ICP, CPP, intracerebral metabolic deranagement and survival.
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Wong KKY, Khong PL, Lin SCL, Lam WWM, Lan LCL, Tam PKH. Post-operative magnetic resonance evaluation of children after laparoscopic anorectoplasty for imperforate anus. Int J Colorectal Dis 2005; 20:33-7. [PMID: 15322835 DOI: 10.1007/s00384-004-0620-6] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/25/2004] [Indexed: 02/04/2023]
Abstract
BACKGROUND AND AIMS Laparoscopic anorectoplasty (LAR) is a relatively new procedure in the treatment of imperforate anus. Using magnetic resonance imaging (MRI), we evaluated the anatomical features of the anorectal region of children treated with LAR and compared this with conventional posterior sagittal anorectoplasty (PSARP). The findings were correlated with functional outcome. PATIENT/METHODS A retrospective review of ten children with the high/intermediate types of imperforate anus underwent LAR between May 2000 and December 2002. MRI of the pelvis was performed post-operatively and a semi-quantitative score was used to assess the degree of sphincter symmetry, peri-rectal fibrosis, and the position of the pull-through rectum. The defecation status of these patients was also recorded. Eight historical patients who had undergone PSARP served as a control group. RESULTS/FINDINGS When compared with PSARP patients, a significantly lower proportion of LAR patients had sphincter asymmetry (40 vs. 100%, p < 0.05) and peri-rectal fibrosis (40 vs. 87.5%, p < 0.05). The positioning of the rectum was, however, central for both groups (90 vs. 87.5%). No statistical correlation was found between defecation status and the degree of sphincter asymmetry or peri-rectal fibrosis. INTERPRETATION/CONCLUSION LAR allows more optimal anatomical reconstruction for patients with the high/intermediate types of imperforate anus. However, additional factors that are not correctable by surgery, such as intrinsic innervation deficiency, also influence the clinical outcome.
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Abstract
Magnetic resonance cholangiography has been shown to be useful in the evaluation of hepatobiliary problems in paediatric patients. Its clinical application in biliary atresia, choledochal cyst, cholelithiasis, bile plug syndrome and liver transplant are illustrated by the following cases.
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Gao S, Wong KS, Hansberg T, Lam WWM, Droste DW, Ringelstein EB. Microembolic Signal Predicts Recurrent Cerebral Ischemic Events in Acute Stroke Patients With Middle Cerebral Artery Stenosis. Stroke 2004; 35:2832-6. [PMID: 15514175 DOI: 10.1161/01.str.0000147035.31297.b6] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Cerebral embolism is a common cause of stroke. Microembolic signals (MES) detected by transcranial Doppler represent ongoing embolisms, but the lack of reliable data about its clinical relevance hinders its widespread use in clinical practice. METHODS We prospectively monitored 114 consecutive acute ischemic stroke patients with middle cerebral artery (MCA) stenosis for MES. The signals on digital audio tape were analyzed by an independent observer who was blinded to all other data. All patients were followed-up for the occurrence of recurrent stroke or transient ischemic attack (TIA) in the indexed MCA territory. RESULTS MES was detected in 25 (22%) patients. The mean number of MES was 18 (range, 1 to 102). MES were more common in patients with severe stenosis (10/21, 48%) than in those with mild-moderate stenosis (4/26, 15%) (Pearson chi2 P=0.02). During follow-up for a mean of 13.6 months (range, 1 to 32), 12 (12%) patients had further ischemic events (10 strokes and 2 TIAs) in the affected MCA region during follow-up. Among these, 7 (58%) had recurred within 1 month (1 recurred within 1 week, the other 6 patients had recurrences in week 3 or 4 after discharge), 3 within 6 months, 1 within 6 to 12 months, and the remaining 1 recurred after 1 year. The presence of MES was the only predictor of a further ischemic stroke/TIA by Cox regression (adjusted odds ratio, 8.45; 95% CI, 1.69 to 42.22; P=0.01) even after controlling for age, sex, diabetes, hypertension, previous stroke, smoking, and acute treatment. CONCLUSIONS In acute stroke patients with MCA stenosis, MES predicts further cerebral ischemia. This procedure should be considered as part of routine investigation and might identify a group of patients who are most likely to benefit from antithrombotic treatment.
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Chu WCW, Leung TF, Chan KF, Yeung DKW, Yeung TK, Cheung HM, Hon EKL, Liew CT, Lam WWM. Wilson's disease with chronic active hepatitis: monitoring by in vivo 31-phosphorus MR spectroscopy before and after medical treatment. AJR Am J Roentgenol 2004; 183:1339-42. [PMID: 15505300 DOI: 10.2214/ajr.183.5.1831339] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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