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C Metreweli

Publications and source records attributed to C Metreweli.

At least 55 records · Page 3Linked to original sources
PubMed2001

US-guided percutaneous biopsy of small (< or = 1-cm) hepatic lesions.

PURPOSE: To determine the accuracy of ultrasonography (US)-guided percutaneous biopsy in diagnosing malignant neoplasms for hepatic lesions 1 cm or smaller. MATERIALS AND METHODS: In this prospective study, 64 consecutive patients with 74 discrete focal hepatic lesions depicted at US were referred for liver biopsy to confirm the exact nature of the lesions. Mean lesion size was 0.84 cm +/- 0.13 (range, 0.5-1.0 cm). Biopsy was performed with an 18-gauge automated biopsy gun in 46 lesions (once [n = 37], twice [n = 7], three times [n = 2]) or a 22-gauge needle in 28 lesions (once [n = 23], twice [n = 4], three times [n = 1]). Measures were taken to ensure accurate and effective lesion sampling. The histologic diagnosis of malignant tumor and findings on follow-up US images of "benign" nodules for 15-39 months were the criterion standard. RESULTS: No complications occurred. All specimens obtained were sufficient for diagnosis. Histologic examination revealed various types of primary and secondary malignant tumors (n = 44), hemangioma (n = 5), cirrhosis (n = 13), focal fatty change (n = 8), focal fatty sparing (n = 2), and abscess (n = 2). The diagnostic discrimination of US-guided biopsy in diagnosing malignant tumors in these small lesions was sensitivity, 98%; specificity, 100%; positive predictive value, 100%; negative predictive value, 97%; and accuracy, 99%. CONCLUSION: Percutaneous biopsy under US control is highly accurate in providing a definitive histologic diagnosis of malignant neoplasms for small hepatic lesions if measures for ensuring precise and effective lesion sampling are taken.

Adolescent↗
PubMed2001

Vesicoureteric reflux and renal scarring in Chinese children.

Vesicoureteric reflux (VUR) and renal scarring are commonly found in children with urinary tract infection (UTI). The prevalence of VUR and scarring may vary between racial groups. There are no published data on the prevalence of VUR and scarring in Chinese children with UTI. A retrospective, single-institution study was made of Hong Kong Chinese children aged less than 5 years with a documented UTI investigated by both micturating cystourethrography and dimercaptosuccinic acid scintigraphy. VUR was identified in 39% of 93 Chinese children with UTI. Renal scarring was present in 28% of boys, which is comparable with published data on Western children. Scarring appears to be less common in Chinese girls with UTI (11%) than in Western girls (30-38% from published data), and its severity is poorly related to VUR grade. There is a significant dependency relationship between grade of VUR and degree of scarring in Chinese boys (p < 0.05). In conclusion, renal scarring appears to be relatively uncommon in Chinese girls. The correlation between grade of VUR and degree of scarring in Chinese boys suggests a relationship, but provides no evidence about the direction of causation.

Child, Preschool↗
PubMed2001

Acute elbow trauma in children: spectrum of injury revealed by MR imaging not apparent on radiographs.

OBJECTIVE: The objective of this study is to evaluate the frequency and significance of unrecognized bone or soft-tissue injury in pediatric patients with elbow trauma assessed with radiographs alone. SUBJECTS AND METHODS: Fifty children (32 boys and 18 girls; mean age, 7.3 years; age range, 2-12 years) with acute elbow trauma were examined with radiography and MR imaging. Radiographs were categorized into those showing normal findings, an effusion, an equivocal fracture, or an unequivocal fracture. MR examinations were assessed for an effusion, fracture, transphyseal fracture extension, physeal injury, bone bruising, and ligament or muscle injury. Average clinical follow-up was 1.6 years (range, 6-28 months) after injury. RESULTS: Radiographs showed normal findings in seven children (14%), an effusion only in 17 children (34%), and an unequivocal or equivocal fracture in 26 children (52%). MR imaging showed an effusion in 48 children (96%); unequivocal fracture in 37 children (74%), including transphyseal fracture in seven children (14%) and other physeal injury in three children (6%); bone bruising in 45 children (90%); ligament injury in six children (14%); and muscle injury in 19 children (38%). A less severe spectrum of injury occurred in children with normal findings on radiographs than in those with an effusion or fracture seen on radiography. Follow-up radiographs did not help in the detection of radiographically occult fractures. MR findings had no appreciable effect on patient treatment and no value in predicting duration of convalescence or clinical outcome at an average of 1.6 years after injury. CONCLUSION: In children with elbow trauma, MR imaging reveals a broad spectrum of bone and soft-tissue injury beyond that recognizable radiographically. However, the additional information afforded by MR imaging has little bearing on treatment or clinical outcome.

Acute Disease↗
PubMed2001

Power Doppler sonography to differentiate tuberculous cervical lymphadenopathy from nasopharyngeal carcinoma.

BACKGROUND AND PURPOSE: Tuberculous lymphadenitis and metastatic nodes from nasopharyngeal carcinoma are common in Asians and are often indistinguishable clinically. Because their treatment depends on prompt diagnosis, we undertook this study to evaluate if power Doppler sonography could distinguish these two pathologic abnormalities. The intranodal vascular appearances of tuberculous neck nodes are compared with benign reactive neck nodes and metastatic nodes from nasopharyngeal carcinoma. METHODS: The appearances of power Doppler sonograms of 42 tuberculous nodes were compared with 28 metastatic nodes from nasopharyngeal carcinoma and 27 benign reactive nodes. The intranodal distribution of vessels and the intranodal vascular resistance of vessels were compared among these three groups. All examinations were performed by the same sonologist (A.A.), who had more than 3 years' scanning experience, and all data analysis was performed by the same investigator (M.Y.). RESULTS: The intranodal vascular distribution in tuberculous nodes was varied and simulated both benign and malignant disease. Avascularity of nodes and displacement of hilar vascularity were frequent in tuberculous nodes. Metastatic nodes from nasopharyngeal carcinoma (resistive index [RI], 0.81+/-0.09; pulsatile index [PI], 1.91+/-0.81) had a higher vascular resistance than did tuberculous nodes (RI, 0.71+/-0.11; PI, 1.34+/-0.55). Tuberculous nodes had a higher vascular resistance than did reactive nodes (RI, 0.66+/-0.09; PI, 1.10+/-0.26). CONCLUSION: Avascularity, displaced hilar vessels, and low intranodal vascular resistance are clues that may suggest the tuberculous nature of neck nodes. However, there is overlap of appearance between tuberculous nodes, benign reactive neck nodes, and metastatic nodes. Thus, histologic analysis is often required for a definitive diagnosis.

Adolescent↗
PubMed2000

Neck node metastases from nasopharyngeal carcinoma: MR imaging of patterns of disease.

BACKGROUND: The purpose was to use MR imaging to document the patterns of nodal involvement in the upper neck in nasopharyngeal carcinoma (NPC). METHODS: The MR images of 150 patients with newly diagnosed NPC were reviewed retrospectively. Nodes were considered abnormal on MR criteria of size, necrosis, and extracapsular spread. RESULTS: Retropharyngeal nodes (RN) were more frequently involved than nonretropharyngeal nodes (NRNs) (94% vs 76% in 115 patients with nodal metastases). NRN involvement without RN was seen in only 7 of 115 patients (6%). Involvement of RN at the level of the oropharynx (82%) was as common as at the nasopharynx (83%) level. Internal jugular nodes were the most frequently involved NRN nodes (72%). Spinal accessory nodal involvement was also common (57%) but seldom in isolation (8%). Submandibular (3%) and parotid (2%) nodal metastases were uncommon and were always associated with advanced nodal metastases in the ipsilateral RN, internal jugular, and spinal accessory regions. CONCLUSION: Retropharyngeal nodes are the first echelons of nodal metastases. Direct lymphatic spread to the neck without involvement of the RN nodes is uncommon. RN metastases at the level of the oropharynx are more common than previously suspected, and this should influence radiotherapy planning. NRN outside the internal jugular and spinal accessory chains are rare and only occur when the usual routes of lymphatic spread have already been blocked by tumor.

Adult↗
PubMed2000

Transcranial Doppler ultrasonography (TCD) in ventilated head injured patients: correlation with stable xenon-enhanced CT.

Disturbance of cerebral vasomotor regulation has been shown to be associated with the severity of traumatic brain injury (TBI). The transient hyperaemic response (THR) test is a test of the pressure autoregulatory response in terms of cerebral blood flow velocity after a brief carotid artery compression. Correlating with the test of cerebral vascular reactivity (CVR) to carbon dioxide by means of passive hyperventilation suggested that the THR test is a simple clinical test for the assessment of cerebral haemodynamic status in head-injured patients.

Adolescent↗
PubMed2000

Correlation of ultrasonographic imaging of congenital muscular torticollis with clinical assessment in infants.

Congenital muscular torticollis (CMT) is a common problem affecting infants and children. There is a general lack of standard clinical classification or objective assessment methods. Ultrasonographic imaging of the sternomastoid muscle (SCM) has been carried out in a consecutive series of 436 infants less than 1 y old presenting with CMT over a 5-y period. All patients were classified into three clinical groups: postural torticollis, muscular torticollis and sternomastoid tumor. The severity of the torticollis was also expressed into four subgroups according to the degree of deficits in passive rotation of the neck. The ultrasonographic image of the affected SCM included the echogenicity, texture, motility, softness and the transverse and longitudinal extent of the involvement. The disturbance in the quantitative measurement of the transverse diameter of the lower and upper third of the SCM and the ratio of the measurement to the normal side was recorded. The qualitative and quantitative changes in the SCM image were found to correlate significantly with the clinical typing and severity of rotational deficits of the neck. Ultrasonographic imaging has important potential clinical application in helping the diagnosis, prognostication and monitoring of progress of CMT longitudinally.

Female↗
PubMed2000

Paranasopharyngeal space involvement in nasopharyngeal cancer: detection by CT and MRI.

Paranasopharyngeal tumour extension (PTE) from nasopharyngeal carcinoma (NPC) is staged in its own subgroup in the American Joint Committee on Cancer classification. Most large clinical trials use computed tomography (CT) to stage PTE, but diagnosis relies on indirect signs of tumour invasion such as asymmetry of the parapharyngeal fat. Magnetic resonance imaging (MRI) has the advantage of directly revealing PTE because of its ability to depict the complex anatomical structures that form the boundary of the nasopharynx. The aim of this study was to compare CT and MRI in the identification of PTE and to determine whether the imaging modality used influenced staging of the disease. The MRI and CT scans of 78 patients (156 parapharyngeal regions) with NPC were assessed for PTE. On MRI, PTE was considered to be positive when there was tumour invasion through the complex anatomical structures of the nasopharyngeal wall. When using CT, it was considered positive when there was: (1) distortion of the parapharyngeal fat plane; or (2) extension beyond a line drawn from the medial pterygoid plate to the lateral aspect of the carotid artery. CT scanning and MRI were compared. PTE was judged to be present in 28 of 78 (36%) patients by MRI and in 41 of 78 (53%) scanning by CT when using criterion 1 or 2. An analysis of the discordant findings revealed that MRI was positive in three sides of the nasopharynx in early tumour extension through the pharyngobasilar fascia but not identified with CT by using criterion 1 or 2. MRI was negative in 20 and 21 sides of the nasopharynx that were judged to be positive on CT by using criterion 1 and 2 respectively. In these patients MRI revealed that the positive CT scan was caused by a large tumour compressing but not invading the parapharyngeal fat space, a metastatic lateral retropharyngeal node, or a combination of the two. The imaging modality used for staging NPC has an impact on the staging of PTE. CT scanning suggested the presence of PTE more frequently than MRI because of its inability to distinguish the primary tumour from lateral retropharyngeal nodes, and direct tumour invasion of the parapharyngeal region from tumour compression. The imaging modality and criteria used for staging PTE should be taken into consideration when assessing the results of clinical studies.

Adult↗
PubMed2000

Longitudinal colour doppler study of superficial lymph nodes in non-Hodgkin's lymphoma patients on chemotherapy.

AIMS/METHODS: A longitudinal study of 22 malignant lymph nodes by colour Doppler (CD) and/or colour power (CP) ultrasonography was undertaken in 12 non-Hodgkin's lymphoma patients to delineate changes in vascularity, and correlate this response with clinical outcome. RESULTS: Reduced vascularity in response to chemotherapy was shown to be a positive prognostic sign. CONCLUSIONS: More persistent nodal vascularity may signify a less favourable prognosis.

Adult↗
PubMed2000

Staging papillary carcinoma of the thyroid: magnetic resonance imaging vs ultrasound of the neck.

AIM: To evaluate the role of magnetic resonance imaging (MRI) for staging local disease and lymph node metastases in papillary carcinoma of the thyroid by comparing MRI with ultrasound (US) of the neck. MATERIALS AND METHODS: Fourteen patients with papillary carcinoma underwent MRI and US. The images were prospectively reviewed for (1) identification of the primary lesion; (2) presence of multifocal thyroid disease; (3) extracapsular extension; (4) invasion into the trachea, oesophagus and major vessels; and (5) presence of lymph node metastases. Correlation was made with the surgical findings. RESULTS: The site of the primary lesion was correctly identified by US in 14 of 14 (100%) and by MRI in 13 of 14 (93%) of patients. Multifocal thyroid tumour was correctly identified by US in two of two patients (100%) and by MRI in zero of two (0%). Extracapsular extension (n = 9), oesophageal invasion (n = 1) and tracheal invasion (n = 2) were identified by MRI in seven, zero, and one, and by US in six, zero and zero patients, respectively. Invasion of the major vessels was not seen. Metastatic cervical nodes were present in 19 nodal groups in 10 patients involving the internal jugular chain (n = 10), posterior triangle (n = 4) supraclavicular fossa (n = 1) and central group (n = 4). Both MRI and US failed to identify metastatic nodes in the central group but correctly identified 14 of the 15 nodal groups outside the central group. CONCLUSION: Ultrasound should be used as the first line of investigation for detecting the primary lesion, multifocal disease and cervical lymphadenopathy. In cases where the primary tumour is not surrounded by normal thyroid tissue MR imaging should be added to assess extracapsular spread, especially into the trachea.

Adolescent↗
PubMed2000

Sonographic appearances of preauricular sinus.

AIM: Preauricular sinuses are a common congenital abnormality. This study was performed to determine their sonographic features. MATERIALS AND METHODS: Fifteen preauricular sinuses (in 13 patients) were examined using a 5-10 MHz transducer to evaluate the nature of the sinus. Surgical correlation was obtained in 11 cases. RESULTS: Sonography detected the sinus in all cases. The maximum width of the sinus tract was 3 mm; it showed a branching pattern in four (27%) patients. Nine sinuses (60%) led to a cystic component, and the remaining six (40%) showed terminal ramification. Gas was identified within the sinus in nine (60%) cases. In the patients that underwent surgery, the diagnosis and the relationship of the sinus/ cystic component to the superficial temporal artery (STA), anterior crus of the helix and the tragus was confirmed and correlated well with the sonographic findings. However, the branching pattern of the sinus tract was difficult to confirm. CONCLUSION: Sonography readily detects preauricular sinuses and demonstrates their relationship to the STA, anterior crus of the helix, and the tragus, and can therefore be helpful in pre-operative assessment. Ahuja, A. T. (2000). Clinical Radiology 55, 528-532.

Adolescent↗
PubMed2000

Differentiation of lymphadenopathy in different forms of carcinoma with Doppler sonography.

AIM: The aim of the study was to show whether it may be possible to characterize malignant nodes of different aetiologies with Doppler imaging. Non-Hodgkin's lymphoma (NHL) and nasopharyneal carcinoma (NPC) were used as the models. MATERIALS AND METHODS: A prospective study was undertaken using colour Doppler sonography in 60 enlarged peripheral lymph nodes of 34 patients with either lymphoma or NPC. The vascular distribution, peak systolic velocity (PSV), end diastolic velocity (EDV), resistivity index (RI) and the pulsatility index (PI) of the largest node on each side of the patient were investigated. RESULTS: The vascular distribution was predominantly 'capsular and central' or 'capsular' in 57 nodes, consistent with previous descriptions, but there was no significant difference in the mean PSV (lymphoma: 20.0 cm/s; NPC: 21.86 cm/s;P > 0.05) and mean EDV (lymphoma: 5.95 cm/s; NPC: 5.07 cm/s;P > 0.05). However, significant differences were shown in the mean RI (lymphoma: 0.71; NPC: 0.81;P < 0.05) and mean PI (lymphoma: 1.43; NPC: 1.88;P < 0.05) of these two groups of lymph nodes. CONCLUSIONS: There is significant difference in the Doppler waveform between malignant nodes affected by lymphoma or NPC, suggesting that further differentiation of malignant nodes may be possible.

Adult↗
PubMed2000

Neck ultrasound in staging squamous oesophageal carcinoma - a high yield technique.

AIM: This study evaluates the use of neck ultrasound in staging squamous oesophageal carcinoma. MATERIALS AND METHODS: A prospective analysis of the clinical, neck ultrasound (US) and thoraco-abdominal computed tomography (CT) findings in 121 patients with squamous oesophageal carcinoma at presentation was performed. The relationship between malignant neck nodes, mediastinal and abdominal adenopathy, location and size of the primary tumour was analysed. RESULTS: Ten of 121 patients (8%) had clinically palpable neck nodes which were deemed malignant in six (5%) following US and fine-needle aspiration for cytology. Of those 111 patients with no palpable neck nodes, 31 (28%) had malignant nodes shown on US. The more cephalad the location of the primary tumour, the higher the frequency of malignant neck nodes which were found in 80%, 52%, 29% and 9% of cervical, upper thoracic, mid-thoracic and lower thoracic oesophageal tumours, respectively. Eleven (29%) of the 38 patients with malignant neck nodes shown on US had no CT evidence of additional adenopathy in the mediastinum or upper abdomen. Neck US altered TNM staging in 22/121 (18%) patients at presentation. CONCLUSION: Neck US frequently detects clinically impalpable metastatic nodes leading to altered TNM staging in patients with squamous oesophageal carcinoma. We advocate its routine use when staging squamous oesophageal carcinoma.

Adult↗
PubMed2000

Detection of parametrial invasion in cervical carcinoma: role of short tau inversion recovery sequence.

AIM: To investigate the role of short tau inversion recovery (STIR) sequence in the detection of parametrial invasion in patients with carcinoma of the cervix. MATERIALS AND METHODS: Axial magnetic resonance imaging (MRI) images of the cervical region using T1 weighted turbo spin echo (TSE), TSE T2, STIR and T1 weighted dynamic gadolinium enhanced SE sequences were obtained in 38 patients with cervical carcinoma. All the images were assessed for the presence or absence of parametrial invasion using a standard scoring system. The diagnostic confidence, image quality, sensitivity, specificity, positive and negative predictive values and accuracy of each sequence were compared. RESULTS: The sensitivity, specificity, positive predictive value, negative predictive value and accuracy for each sequence in the diagnosis of parametrial invasion were: 60%, 80%, 32%, 93% and 78% for unenhanced T1W sequence; 90%, 92%, 64%, 98% and 92% for TSE T2 sequence; 90%, 94%, 69%, 98% and 93% for STIR sequence; and 90%, 80%, 41%, 98% and 82% for dynamic T1W sequence, respectively. Image quality and diagnostic confidence were both better for STIR and T2 compared to the dynamic T1 sequence. CONCLUSION: Dynamic T1W imaging is inferior to STIR and TSE T2 sequences. STIR is of similar value in the detection of parametrial invasion in cervical carcinoma as a TSE T2W sequence; their simultaneous use is not justified.

Adenocarcinoma↗
PubMed2000

Sonographic evaluation of thyroglossal duct cysts in children.

BACKGROUND AND AIMS: Thyroglossal duct cysts (TDC) in children have a variable sonographic appearance. Some reports have suggested that TDCs appear on ultrasound as well defined, cystic masses with thin walls and posterior enhancement, whereas others have documented a heterogeneous echopattern within these lesions. In our experience, although TDCs in children have a variable ultrasound appearance, the most common appearance is that of a pseudosolid mass closely related to the hyoid bone. In this study we report on 23 patients with thyroglossal duct cysts and document the ultrasonic patterns. PATIENTS AND METHODS: All patients in whom the diagnosis of TDC was made clinically (by at least two head and neck surgeons) and in whom ultrasound detected a cystic mass related to the hyoid bone, were included in this study. Sonograms of 23 children with TDCs were reviewed. The features evaluated included their location, internal echogenicity, posterior enhancement, the presence of septa, a solid component and a fistulous tract. The echopattern was not correlated with the biopsy results. RESULTS: Three patterns of TDCs were identified: anechoic (13%); pseudosolid (56.5%); and a heterogeneous pattern (30.5%). The majority were midline (82.6%), showed posterior enhancement (56.5%), and had thin walls (82.6%). CONCLUSION: On ultrasound, TDCs in children are not simple cysts but have a complex pattern ranging from a typical anechoic cyst to a pseudosolid appearance (most common).Ahuja, A. T. (2000). Clinical Radiology55, 770-774.

Adolescent↗
PubMed2000

Incidence of adverse events after I.V injection of MR contrast agents in a Chinese population. A comparison between gadopentetate and gadodiamide.

PURPOSE: To study the incidence of adverse events after i.v. injection of MR contrast agents in a Chinese population. A comparison was made between an ionic contrast agent (dimeglumine gadopentetate, Magnevist) and a non-ionic contrast agent (gadodiamide, Omniscan). MATERIAL AND METHODS: During a 24-month period, 2,049 Chinese patients who randomly received an i.v. bolus injection of either Magnevist or Omniscan were investigated. All patients were questioned for the presence of any generalized or localized adverse reaction on the following day after the MR examination according to a standardized questionnaire. RESULTS: Three hundred and nine out of 2,049 patients (15%) reported an adverse event. There was a higher incidence of adverse events in patients receiving Magnevist as compared to those receiving Omniscan injection. All reported adverse events were clinically mild and required neither treatment nor hospitalization. CONCLUSION: There was a higher incidence of adverse reaction in patients receiving Magnevist than in those receiving Omniscan.

Adolescent↗
PubMed2000

Assessment of optic nerve compression in Graves' ophthalmopathy. The usefulness of a quick T1-weighted sequence.

PURPOSE: Diagnosis of optic nerve compression can be difficult in patients with equivocal clinical signs. We examined the usefulness of a quick coronal MR sequence performed at a predetermined plane as a screening tool for selecting patients at high risk of optic nerve compression. MATERIAL AND METHODS: Direct coronal images of the orbit were obtained in 37 patients with Graves' disease in a predetermined plane. The muscular indices (MI) of each orbit were calculated. Mann-Whitney U-Wilcoxon rank sum test was used to assess if there was any statistically significant difference between patients with and without signs of optic nerve compression. The ROC curve was used to identify a value useful for discriminating patients with a higher risk of developing optic nerve compression. RESULTS: There was a statistically significant difference (p<0.05) in the MI between patients with and without optic nerve compression. An MI of -0.48 had 100% sensitivity, 89% specificity and 91% accuracy in identifying patients with optic nerve compression. CONCLUSION. A quick coronal MR image obtained at the mid-orbital plane is useful in screening patients with Graves' disease for optic nerve compression.

Female↗