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S B Walkden

Publications and source records attributed to S B Walkden.

6 recordsLinked to original sources
PubMed1996

Transrectal ultrasound in the evaluation of cervical carcinoma and comparison with spiral computed tomography and magnetic resonance imaging.

38 women with biopsy proven untreated cervical carcinoma were prospectively studied with transrectal ultrasound (TRUS), spiral computed tomography (SCT) and magnetic resonance imaging (MRI). 20 women had radical hysterectomy and pelvic lymphadenectomy with detailed histological evaluation of the parametra. The echographic features of cervical carcinoma on TRUS are a hypoechoic (60%) or isoechoic (40%) (relative to normal uterine muscle/cervical stroma), poorly defined mass lesion with indistinct margins in an enlarged cervix. This relatively high percentage of isoechoic tumours and relative lack of contrast resolution may pose a problem in the identification of some tumours, and to our knowledge has not been previously reported. Further limitations of TRUS are in the evaluation of advanced cervical cancer, due to bulky tumours rendering poor access to the parametrium and pelvic sidewall. The overall accuracy in staging of early cervical cancer (less than stage 2b) was 85% for examination under anaesthesia (EUA), 75% for TRUS, 65% for MRI and 50% for SCT. The positive predictive value in evaluating the parametra in this group of patients was also lower for SCT (14%) and MRI (33%) compared with TRUS (100%). In the evaluation of advanced cervical cancer (stage 2b or higher), there was poor correlation between TRUS and EUA, with MRI showing the best correlation with EUA. We conclude that SCT is inferior to both TRUS and MRI in the staging of early stage cervical cancer.

Adult↗
PubMed1995

Technical note: an evaluation of the routine use of rectal air in computed tomography of the pelvis.

We have performed computed tomographic examinations of the pelvis in 50 patients, using rectally administered air to outline the rectosigmoid colon. Bowel cleansing was not performed and smooth muscle relaxants were not used. The procedure was well tolerated by all patients, and diagnostic images were obtained in all cases. There were no complications. This is a safe, low cost and easily administered form of bowel contrast. We recommend it as the technique of choice in routine pelvic computed tomography.

Colon, Sigmoid↗
PubMed1995

Detection and assessment of intracranial aneurysms: value of CT angiography with shaded-surface display.

OBJECTIVE: The purpose of this study was to evaluate the efficacy of circle of Willis CT angiography with shaded-surface display in the detection and assessment of suspected intracranial aneurysms. MATERIALS AND METHODS: Twenty-three patients who had clinical or radiologic suspicion of intracranial aneurysms were studied prospectively with CT angiography and conventional angiography. The images were obtained and interpreted in a double-blind fashion by different radiologists. Conventional angiography, which was the reference standard in this study, diagnosed 17 aneurysms in 15 patients. The usefulness of the two types of images for surgical planning was evaluated by two neurosurgeons. RESULTS: No aneurysms were detected with either technique in eight patients. Both techniques showed 15 aneurysms in 14 patients. The maximum dimensions were less than 3.0 mm in three cases, 3.0-5.0 mm in four cases, and greater than 5.0 mm in eight cases. With conventional angiography used as the reference standard, CT angiography has one false-positive and two false-negative findings, resulting in a sensitivity of 88% (15/17) and a specificity of 89% (8/9). For 12 of 15 aneurysms, CT angiography was rated equal or superior to conventional angiography in depicting all aspects (shape, orientation, neck, and parent vessel) of the aneurysms. CONCLUSION: We were able to detect aneurysms of the circle of Willis as small as 2 mm in size. Using conventional angiography as the reference standard, CT angiography has a sensitivity of 88% and a specificity of 89% for the detection of aneurysms in the circle of Willis. In almost all cases, CT angiography was equal or superior to conventional angiography in characterizing the aneurysms for surgical planning.

Adolescent↗
PubMedDate not supplied

Is routine computed tomographic (CT) scanning necessary in suspected basal skull fractures?

The aim of this prospective observational study was to assess the yield of routine fine-cut computed tomographic (CT) scans in patients with suspected basal skull injuries. Over an 8 month period in 1994, 500 consecutive head-injured patients were examined for clinical signs of basal skull fracture and underwent fine-cut (5 mm) CT scans through the skull base in addition to standard (10 mm) cuts through the vault. Clinical signs were present in 144 patients (144/500, 28.8 per cent) of which 75 (75/144, 52 per cent) had corresponding CT evidence of fracture. A further 22 patients (22/500, 4.4 per cent) had no clinical signs but fractures were seen on CT. The presence of cranial nerve injury, cerebrospinal fluid leak, epistaxis, periorbital bruising, and two or more signs, were more likely to be associated with positive CT scans (P < 0.001, chi 2 tests). The incidence of associated mass lesions was 50.5 per cent, of which 55.1 per cent required craniotomy. This was significantly higher than in patients without evidence of skull base fracture (16.6 per cent) (P < 0.001, chi 2 27.165). Six patients, two of whom had meningitis, required surgical repair of the dural defects seen on CT. The diagnostic yield of routine fine-cut CT scans in this sub-type of head injury is 52 per cent, and is of value in detecting associated mass lesions or significant dural defects which may require surgical intervention.

Adolescent↗