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C Metreweli

Publications and source records attributed to C Metreweli.

At least 109 records · Page 6Linked to original sources
PubMed1999

MRI of local disease in nasopharyngeal carcinoma: tumour extent vs tumour stage.

The purpose was to use MRI to study in detail local tumour extension in patients presenting with nasopharyngeal carcinoma (NPC) and to compare the extent of local disease with the current T-stage classification. MR images of 150 patients with newly diagnosed nasopharyngeal carcinoma were obtained on a 1.5 T unit. 10 extranasopharyngeal sites were analysed for tumour involvement. The number of concurrently involved sites was determined. The extent of tumour invasion was compared with staging as defined by the fifth edition of the AJCC classification. The T-stage distribution was T1 21%, T2 16%, T3 41% and T4 22%. The frequencies of tumour invasion into an individual site, and the mean number of other concurrently involved sites were as follows: skull base 63%, 3.9 sites; parapharyngeal 56%, 3.9 sites; nasal cavity 53%, 4.0 sites; oropharyngeal 17%, 5.2 sites; sphenoid sinus 27%, 5.6 sites; cranium 21%, 5.7 sites; infratemporal fossa 2%, 6.3 sites; ethmoid sinus 14%, 6.5 sites; orbit 5%, 7.0 sites; maxillary sinus 5%, 7.1 sites; and hypopharynx 0%, 0 sites. Extranasopharyngeal extension commonly occurred superiorly into the skull base rather than inferiorly to the oropharynx (p < 0.0001). Anatomical sites defined within the same T-stage category had different frequencies of involvement and different frequencies of concurrently involved sites. Oropharyngeal involvement (T2 stage) was associated with a number of concurrently involved sites comparable to structures in the T3 category. Maxillary and ethmoid sinus involvement (T3 stage) were associated with a number of involved sites comparable to the T4 stage. Invasion of the maxillary antrum and orbit are markers of the most bulky form of NPC.

Adult↗
PubMed1999

Comparison of laparoscopic sonography with surgical pathology in the evaluation of pelvic lymph nodes in women with cervical cancer.

OBJECTIVE: This study compared laparoscopic sonography with surgical pathology in the evaluation of pelvic lymph nodes in women with cervical cancer. SUBJECTS AND METHODS: Intraoperative laparoscopic sonography of pelvic lymph nodes was performed in 31 women with biopsy-proven cervical cancer. A lymph node that was rounded (longitudinal-transverse axis ratio of <2) or showed absence of central hilum was defined as positive for metastasis. For comparison, lymph nodes from each hemipelvis were grouped anatomically into paraaortic, common, internal, and external iliac chains during evaluation on laparoscopic sonography and on surgical pathologic examination. RESULTS: Pelvic dissection in 31 women yielded 630 lymph nodes. There were 54 metastatic nodes in 12 women. Laparoscopic sonography revealed 32 (59%) of all pathologically metastatic lymph nodes. Sensitivity on laparoscopic sonography when comparing groups by hemipelves was 93.3% and by anatomic lymph node chains was 76.2%. Metastatic nodes were most commonly located in the common iliac region and were characteristically rounded, hypoechoic, showed absence of central hilum, and occasionally showed central necrosis. Nine (28%) of 32 metastatic lymph nodes revealed by laparoscopic sonography measured 1 cm or less. Six benign nodes in four patients were also visualized with laparoscopic sonography. CONCLUSION: Laparoscopic sonography achieved a sensitivity exceeding 90% in the detection of metastatic lymph nodes in the hemipelves of women with cervical cancer. Laparoscopic sonography is a feasible and promising technique for the evaluation of pelvic lymph nodes in women with cervical cancer and merits further evaluation.

Adult↗
PubMed1999

Sonography compared with radiography in revealing acute rib fracture.

OBJECTIVE: This study was undertaken to compare the sensitivities of sonography and radiography for revealing acute rib fracture. SUBJECTS AND METHODS: Chest radiography and rib sonography were performed on 50 patients with suspected rib fractures. Sonography was performed with a 9- or 12-MHz linear transducer. Fractures were identified by a disruption of the anterior margin of the rib, costochondral junction, or costal cartilage. The incidence, location, and degree of displacement of fractures revealed by radiography and sonography were compared. Sonography was performed again after 3 weeks in 37 subjects. RESULTS: At presentation, radiographs revealed eight rib fractures in six (12%) of 50 patients and sonography revealed 83 rib fractures in 39 (78%) of 50 patients. Seventy-four (89%) of the 83 sonographically detected fractures were located in the rib, four (5%) were located at the costochondral junction, and five (6%) in the costal cartilage. Repeated sonography after 3 weeks showed evidence of healing in all reexamined fractures. Combining sonography at presentation and after 3 weeks, 88% of subjects had sustained a fracture. CONCLUSION: Sonography reveals more fractures than does radiography and will reveal fractures in most patients presenting with suspected rib fracture. Further scientific studies are needed to clarify the appropriate role for sonography in rib fracture detection.

Adult↗
PubMed1999

Thyroglossal duct cysts: sonographic appearances in adults.

BACKGROUND AND PURPOSE: Previous reports have suggested that thyroglossal duct cysts (TDCs) appear on sonograms as well-defined cystic masses with thin walls and posterior enhancement. In our experience, however, TDCs have a variable sonographic appearance. We report our findings in 40 patients with TDCs and document the variability of sonographic patterns. METHODS: All patients in whom the diagnosis of TDC was made clinically (by at least two head and neck surgeons) and sonography detected a cystic mass related to the hyoid bone were included in this study. Sonograms of 40 patients with TDCs were reviewed. The features evaluated were the location, internal echogenicity, posterior enhancement, presence of septa, solid component, and fistulous tract. The echo pattern was not compared with the biopsy results. RESULTS: Four patterns of TDCs were identified: anechoic (28%), homogeneously hypoechoic with internal debris (18%), pseudosolid (28%), and heterogeneous (28%). The majority showed posterior enhancement (88%), were midline (63%), and infrahyoid in location (83%). Only half of all TDCs showed a typical thin wall. CONCLUSION: On sonograms, TDCs in adults are not simple cysts, as previously suggested, but have a complex pattern ranging from a typical anechoic to a pseudosolid appearance.

Adult↗
PubMed1999

Magnetic resonance imaging of the eustachian tube in nasopharyngeal carcinoma: correlation of patterns of spread with middle ear effusion.

OBJECTIVE: The purpose of this study was to use multiplanar high-resolution magnetic resonance imaging (MRI) to detail the patterns of tumor spread in nasopharyngeal carcinoma (NPC) and to correlate the findings with the presence of an effusion in the middle ear and mastoid. MATERIALS AND METHODS: Magnetic resonance imaging was performed in 51 patients with newly diagnosed NPC, providing 102 individual sides for analysis. RESULTS: Fifty-nine lateral walls of the nasopharynx were involved by NPC. Tumor involved the lateral recess (55), eustachian tube orifice (41), levator palatini (LP) (32), torus tubarius (TT) (21), pharyngobasilar fascia (38), tensor palatini (TP) (17), parapharyngeal fat space (PFS) (19), main body of the cartilaginous eustachian tube (CET) ( 13), bony eustachian tube (0). middle ear (0), and inner ear (0). Effusions were present in 32 (54%) of the 59 involved sides. Effusions were found to be associated with the following patterns of spread: tumor causing major displacement of the CET without invasion (3 of 4), tumor invading TT or LP with minor displacement of the TT (4 of 7) or major displacement of the CET (7 of 7) and advanced invasion involving the TP, PFS, or CET with major displacement of CET (18 of 19). Effusions were not seen in tumors without invasion that were restricted to the lateral recess or eustachian tube orifice either with no displacement (O of I I) or with minor displacement (O of 1 1) of the TT. Effusions were present in 28 of 30 cases with major displacement of the main body of the CET, 4 of 18 with minor displacement of the TT, and 0 of 11 with no displacement. Displacement of the eustachian tube was a significant factor in the production of an effusion (p < 0.00001) and remained significant even after exclusion of all cases of advanced invasion (p < 0.0001). CONCLUSION: The cause of an effusion in NPC is multifactorial. Magnetic resonance imaging has shown invasion of the tensor palatini muscle in patients with an effusion, suggesting a functional cause. However, displacement of the eustachian tube is a significant factor in patients with middle ear and mastoid effusions.

Adult↗
PubMed1999

Magnetic resonance imaging and audiologic assessment of middle ear effusions in patients with nasopharyngeal carcinoma before radiation therapy.

OBJECTIVE: The aim of this study was to assess the performance of clinical methods, viz. otoscopy, pure-tone audiometry, and tympanometry in diagnosing middle ear effusions (MEEs) using magnetic resonance imaging as a reference standard. STUDY DESIGN: A retrospective study of 46 patients with newly diagnosed nasopharyngeal carcinoma was performed comparing clinical evaluation and audiometry results with magnetic resonance imaging findings obtained before radiation therapy. RESULTS: Twenty-two (25%) of the temporal bones imaged had both MEE and mastoid effusions, 24 (27%) had only middle ear fluid, and 29 (33%) had mastoid fluid alone. The sensitivity for tympanometry, audiometry, and otoscopy in detecting fluid in the middle ear was 96%, 92%, and 80%, respectively. Although tympanometry was most sensitive in diagnosing MEE, there was no statistically significant difference when comparing the overall accuracy of pure-tone audiometry air-bone gap and tympanometry (p = 0.7, chi-square test). Flat curve tympanograms (type B) only achieved a sensitivity of 45% but were of high specificity (92%). Forty-nine percent with negative pressure tympanograms (mean air pressures > -100 daPa) had no MEE. CONCLUSIONS: Using magnetic resonance imaging as a reference standard, tympanometry is the most sensitive audiologic test in detecting the presence of MEE. The overall accuracy of tympanometry, pure-tone audiometry air-bone gap, and otologic examination was, however, not significantly different.

Acoustic Impedance Tests↗
PubMed1999

Metastatic adenopathy from nasopharyngeal carcinoma: successful response to radiation therapy assessed by color duplex sonography.

BACKGROUND AND PURPOSE: Although the role of gray-scale sonography for neck nodes is well documented, it plays a limited role in the evaluation of nodal response to treatment. This preliminary limited study sought to determine color duplex sonographic changes in successfully treated metastatic nodes from nasopharyngeal carcinoma. METHODS: Fourteen patients with nodal metastases from nasopharyngeal carcinoma were studied. A pretreatment sonogram was obtained for all patients. Patients were divided into two groups of seven: in one group, repeat sonograms were obtained 8 weeks after completion of treatment; in the second group, sonograms were obtained 16 weeks after treatment. The features studied included distribution of intranodal vascularity, resistive and pulsatility indexes, and peak systolic velocity. In 11 patients, follow-up sonograms were obtained 1 year after treatment. RESULTS: The majority (90%) of malignant nodes from nasopharyngeal carcinoma have an increased central and peripheral vascularity, a high resistive index (0.8), and a high pulsatility index (1.8). After radiation therapy to the nodes, a reduction in intranodal vascularity and a statistically significant reduction in the resistive index (0.58 to 0.59) and pulsatility index (0.91 to 0.93) are found. Although a similar reduction in the peak systolic velocity is observed, it is not statistically significant. CONCLUSION: Our preliminary findings suggest that after radiation therapy for malignant nodes in nasopharyngeal carcinoma, a reduction in intranodal vascularity is found, and the resistive and pulsatility indexes may return to benign parameters as early as 8 weeks after completion of treatment.

Adult↗
PubMed1998

Renal length in Chinese children: sonographic measurement and comparison with western data.

PURPOSE: The purpose of this study was to determine the normal range of renal length in Hong Kong Chinese children and compare it with Western data. METHODS: Two hundred fifty children undergoing routine abdominal sonography were examined prospectively, and the maximum length of 1 kidney per child was recorded. Ages ranged from newborn to 19 years, and there were 109 girls and 141 boys. Similar data from Australian children involved maximum lengths of both kidneys in 554 children ranging in age from newborn to 14 years. There were 361 girls and 193 boys. No children had known renal disease. RESULTS: There was no statistically significant difference between the mean renal lengths of girls and boys. Statistical comparison of the data from Hong Kong and Australia showed no significant difference except in the 8-12 month age group (this difference is unlikely to be clinically significant). Although direct statistical comparison with published data on kidney lengths in 203 U.S. children was not possible, plots of the three sets of data were strikingly congruent. CONCLUSIONS: Despite expectations that smaller body size in Hong Kong children might equate to smaller kidneys, comparison with 2 sets of Western data showed no clinically significant difference in renal length between the 3 groups.

Adolescent↗
PubMed1998

Cervical lymphadenopathy: sonographic differentiation between tuberculous nodes and nodal metastases from non-head and neck carcinomas.

PURPOSE: Clinical examination alone cannot differentiate between cervical tuberculous lymphadenitis and cervical nodal metastases from non-head and neck (NHN) carcinomas because the distributions of involved lymph nodes are similar. We evaluated the sonographic features of cervical lymph nodes that could be used to differentiate between the 2 categories of nodes. METHODS: We retrospectively reviewed sonograms of abnormal cervical lymph nodes in 47 patients with proven cervical tuberculous lymphadenitis and in 22 patients with proven nodal metastases from NHN carcinomas. RESULTS: Abnormal nodes in tuberculous lymphadenitis and nodal metastases from NHN carcinomas were commonly found in the supraclavicular fossa (15% and 38%, respectively) and the posterior triangle (70% and 41%, respectively). Statistically significant (p < 0.05) features for differential diagnosis were lymph nodes' longest diameter, echogenicity, short-to-long axis ratio, appearance of surrounding soft tissues, and presence of intranodal cystic necrosis, matting, and posterior enhancement. Nodal size, echogenicity, presence of an echogenic hilum, calcification, coagulation necrosis, and sharpness of borders helped in identifying the abnormal lymph nodes. CONCLUSIONS: Sonographic features that helped to differentiate between the 2 categories of nodes were shape, edema of surrounding soft tissue, homogeneity, intranodal cystic necrosis, matting, and posterior enhancement.

Adult↗
PubMed1998

Ultrasound assessment of mild splenomegaly: spleen/kidney ratio.

BACKGROUND: Ultrasound may detect mild splenomegaly before it is clinically palpable. Knowledge of the normal range of spleen size in the population being examined is a prerequisite. Racial differences in splenic length could result in incorrect interpretation of splenic measurements. OBJECTIVE: To measure the normal values of splenic length in Hong Kong Chinese children and compare the results with Western data; to determine whether there is a constant ratio of the length of the spleen to the left kidney, which could be used to diagnose splenomegaly without reference to a nomogram. MATERIALS AND METHODS: Ultrasound was used to measure maximum splenic and left kidney length in 256 Chinese children to obtain normal values for spleen length and to determine the spleen/kidney ratio. Results. Splenic length in Chinese children is similar to Western children up to the age of about 15 years. The spleen/left kidney ratio is strikingly constant with a mean value of 1. Using 2 SD above the mean as a guide, the upper limit of normal for the spleen/kidney ratio is 1.25. CONCLUSION: Splenomegaly should be suspected in children if the spleen is more than 1.25 times longer than the adjacent kidney.

Adolescent↗
PubMed1998

Magnetic resonance cholangiography--feasibility and application in the paediatric population.

OBJECTIVE: To assess the feasibility of magnetic resonance cholangiography (MRC) in paediatrics. MATERIALS AND METHODS: MRC was attempted in 41 children from 1 week to 14-years. There were three groups: (1) children studied with MRI for non-biliary problems as controls; (2) infants with jaundice; and (3) older children suspected of biliary disease. The examination was successfully performed in 35 children, which included 12 children studied for non-biliary problems, 12 infants with jaundice, and 11 older children with suspected biliary disease. RESULTS: In group 1, the entire common duct was visualised in all 12 children. In group 2, successful demonstration of the common duct was achieved in two of the ten infants with subsequent confirmation of normal bile duct patency. In the last group of patients with suspected biliary disease, MRC gave good anatomical display of six choledochal cysts but failed to demonstrate the anomalous choledochopancreatic channel. It helped to confirm the diagnosis of two cases of pancreatic head cysts, and one case of Caroli's disease. CONCLUSION: MRC can be applied to the paediatric population, but its value depends on the type of problem to be evaluated. With current spatial resolution, its value in the diagnosis of biliary atresia is probably limited because it cannot reliably demonstrate the bile ducts in young infants with non-obstructive jaundice. In older children, it could provide a non-invasive anatomical display of the biliary tree and its disease. It has a potential role in addressing problematic cases encountered during ultrasonography.

Biliary Tract Diseases↗
PubMed1998

Intracortical osteosarcoma.

Intracortical osteosarcomas originate in the bone cortex and represent the rarest type of osteosarcoma. We describe the clinical, radiological and histological features of an intracortical osteosarcoma occurring in the femur of a young man and discuss the pertinent features of this tumour compared to those previously reported.

Adult↗
PubMed1998

Solitary cystic nodal metastasis from occult papillary carcinoma of the thyroid mimicking a branchial cyst: a potential pitfall.

Thyroid carcinoma presenting as cervical lymph node metastasis with a clinically normal neck indicates an aggressive tumour of the thyroid. When the nodal metastasis is solitary and cystic, with no obvious suspicious thyroid mass on ultrasound (US) it may be mistaken for a branchial cyst. As the management of these two conditions is different, it is important to make a correct pre-operative diagnosis. We present the US features that help in distinguishing the two.

Adult↗