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H E Deans

Publications and source records attributed to H E Deans.

10 recordsLinked to original sources

Magnetic resonance imaging appearances of the uterus following microwave endometrial ablation.

AIM: Microwave endometrial ablation (MEA) is a treatment for dysfunctional uterine bleeding. It is a second generation ablative technique which is as effective as hysteroscopic methods but quicker and easier to perform. Our aim is to describe the Magnetic Resonance Imaging (MRI) appearances of the uterus following this procedure. METHODS: 15 women underwent MRI immediately before MEA, and again at one day and 4 months after treatment. T1 and T2 sequences were performed at 1.0T using a body coil. Images were assessed by 2 independent observers for quantitative and qualitative changes. Clinical questionnaires were completed before treatment and at 4 months. RESULTS: On images obtained one day post-ablation, 14 patients had a low signal intensity band subjacent to the treated area of the endometrial cavity on T2 images. Imaging at 4 months showed significant amounts of endometrial tissue in 11 patients, including 3 of the 6 patients who were amenorrhoeic. There were no changes in the appearances of myometrium or uterine dimensions and there were no haematometra. CONCLUSIONS: The detection of residual endometrium by MRI means that unopposed oestrogen hormone replacement therapy should be avoided after MEA, even in women who have amenorrhoea. Thepost-operative sub-endometrial low signal intensity zone corresponds to the region of tissue necrosis detected on vital staining of the treated uterus in in vivotesting. Depth of tissue destruction is a surrogate marker for clinical effectiveness. MRI may have a role in early assessment of patients participating in clinical research who are undergoing a modified MEA technique while retaining their uterus.

Cervix Uteri↗

The accuracy of "one-stop" diagnosis for 1,110 patients presenting to a symptomatic breast clinic.

UNLABELLED: To minimise delay in diagnosis and reduce patient anxiety, triple assessment with immediate reporting has been used in our symptomatic breast clinic since 1991. This article examines the accuracy of the diagnostic modalities used and the efficacy of the "one-stop" diagnostic policy. The data on 1,110 new patients presenting to the symptomatic breast clinic between January and July 1993, were analysed and subsequent three year follow-up and outcome established. Fine needle aspiration cytology (FNAC) gave the highest predictive value (97.3%) with a sensitivity of 93.5% and a specificity of 98.1%. Ultrasonography provided a 97.0% prediction with a sensitivity of 88.9% and a specificity of 97.4%, whereas mammography had a prediction of 96.4% with sensitivity of 93.2% and a specificity of 96.7%. When the mammogram or ultrasound scan were reported as unequivocally benign (M1), there were no missed cancers. The false positive and false negative rates for FNAC were 0% and 1.4%, respectively. Following assessment, a diagnosis was made in 96% of patients. Sixty-two percent of the patients were discharged at the first clinic visit. Four breast malignancies were subsequently diagnosed in the discharged group; two with new microcalcifications due to ductal carcinoma in situ, one with invasive disease in a different quadrant of the breast from that originally investigated, and in one patient the cancer was missed. CONCLUSION: A "one-stop" symptomatic breast clinic provides an accurate and effective means of establishing a correct diagnosis.

Adolescent↗

Incident round cancers: what lessons can we learn?

At the time of implementation of the National Health Service Breast Screening Programme a range of targets were set, and have since been updated. This study looks at a subset of cancers detected by screening - the incident round cancers - which are not currently identified and addressed by the targets. In our first incident round we screened 24838 women and detected 112 breast cancers in 111 women. On the basis of a two-stage retrospective evaluation of the prevalent round mammograms in these 111 women, we classified the prevalent mammograms as false negative 21 (19%), minimal signs 32 (28%) and new tumours 59 (53%). Analysis of the radiographic features revealed a disproportionate number with parenchymal deformity (21%) and asymmetry (17%) among the missed tumours when compared to all tumours detected by our screening programme (12% and < 1%, respectively). Identification and quantification of these incidence detected missed cancers could be incorporated into the Quality Assurance Data Set, and used as another performance indicator. Reviewing the mammograms proved a valuable teaching exercise and has allowed us to develop a test set of challenging mammograms.

Breast Neoplasms↗

Routine receiver operating characteristic analysis in mammography as a measure of radiologists' performance.

A system for calculating receiver operating characteristic (ROC) curves from routine audit data is described. Both diagnostic opinion and pathology outcome data from the symptomatic mammography department were recorded in an audit database, from which ROC curves were calculated. A comparison of overall radiologists' performance was made and the appropriate performance indices discussed. Similar data were collected from the breast screening centre where the same radiologists read mammograms. The radiologists' performance in the symptomatic department was compared with that in the breast screening centre and was found to be better in the screening centre. The difference could not be wholly attributed to the different age distribution of women and highlighted the different nature of the diagnostic task and the differing sampled populations. ROC curves were drawn for different clinical signs to determine any particular area of difficulty the radiologist may experience. ROC analysis as part of routine audit can be used for maintaining and improving the quality of an individual's performance, and targeting learning on areas of particular weakness.

Adult↗

A novel diagnostic index for use in the breast clinic.

The diagnostic accuracy of clinical examination, mammography, ultrasonography and fine needle aspiration (FNA) cytology in discriminating between benign and malignant breast lesions has been retrospectively assessed in 603 patients who attended the Professorial Breast Clinic and then underwent surgical biopsy, in Aberdeen Royal Infirmary, between January 1989 and September 1992. In this series of patients, FNA cytology gave the highest overall prediction of malignancy (92.6%) with a sensitivity of 87% and a specificity of 98%, whilst ultrasonography gave the lowest correct overall prediction (75.6%), with a sensitivity of 70% and a specificity of 79%. Using all the available findings (clinical examination, mammography, ultrasonography, FNA) as well as the patients' age, a stepwise logistic discriminant analysis was used to derive a mathematical equation for use as a novel diagnostic index. Weighted scores, derived from each variable, were used in the discriminant equation to predict the likelihood of malignancy in patients of different ages (>90%). For young patients (<35 years) the discriminant analysis predicted the diagnosis in 98% of women correctly. Quadruple assessment provides an opportunity for establishing the likely diagnosis in most patients the same day they visit the Breast Clinic. The diagnostic index, currently being evaluated prospectively in our breast clinic, may be a further aid to establishing a correct diagnosis.

Adult↗

Fetal fat measurement by magnetic resonance imaging.

A method to assess the average percentage of fetal fat with respect to other fetal tissue is described. This method was then used to assess the percentage of fat in 13 normal fetuses who had a magnetic resonance imaging (MRI) examination late in pregnancy (38-41 weeks). The scans of a further 13 fetuses of diabetic mothers and one case of intrauterine growth retardation (IUGR), all of whom had MRI examinations in the last 3 years, were reviewed and similar calculations were carried out. Whilst the percentage fat range in the normal group was large, it was still possible to discern a difference between the normal, diabetic and IUGR cases.

Adipose Tissue↗

Technetium 99m HMPAO scanning in patients with subarachnoid haemorrhage: a preliminary study.

Technetium 99m hexamethylpropylene amine oxime (HMPAO) is an agent which, when injected intravenously, gives images which reflect cerebral blood flow. Seven patients who had suffered subarachnoid haemorrhage were examined by cerebral angiography and by 99Tcm HMPAO scanning. The two studies were compared and in six cases there was evidence of decreased cerebral perfusion in relation to the ruptured aneurysm causing the subarachnoid haemorrhage. In one case no cause for the haemorrhage was demonstrated angiographically, and the HMPAO study was normal. In two of the six cases, spasm of the cerebral artery distal to the ruptured aneurysm was seen angiographically and it appears that 99Tcm HMPAO scanning does not correlate with gross arterial spasm but reflects smaller degrees of cerebral underperfusion not demonstrable by angiography. The results demonstrate a relationship between local decreased cerebral perfusion and ruptured cerebral aneurysm and may be of use in determining which aneurysm has bled in patients who have more than one aneurysm demonstrated angiographically.

Female↗

Magnetic resonance imaging of the parotid glands using inversion-recovery sequences at 0.08 T.

One hundred and eight examinations on 103 patients with suspected disease of the salivary glands were studied using a 0.08 T resistive magnet and inversion-recovery pulse sequences. Sixty-eight patients who had a mass lesion within a salivary gland later had surgery, and specimens were obtained for histological diagnosis. The remaining 35 patients were diagnosed on clinical grounds. In all cases the clinical findings were compared with the appearances on magnetic resonance imaging (MRI). The use of inversion-recovery pulse sequences allowed accurate localization of all tumour masses and, because of the clarity with which blood vessels were displayed, the precise relationship of any parotid mass to the retromandibular vessels and hence the facial nerve was possible. Whilst MRI did not display any pathognomonic features to allow the differentiation of malignant cell types or the differentiation of invasive malignant tumours from chronic inflammatory disease, it was possible to differentiate parotitis from Mikulicz's disease and to diagnose cysts and pleomorphic adenomas by their appearances on MRI.

Cysts↗

Magnetic resonance imaging of the orbits using a binocular surface coil.

Sixty subjects, including 12 normal volunteers, have been studied using the Aberdeen 0.08 T magnetic resonance imager. A wide range of pathological conditions, including both ocular and and orbital disease, have been examined using a specialized binocular surface coil. The images produced using this coil are superior to those made with a head coil and have the advantage of demonstrating both eyes simultaneously. Each patient has been studied using a pulse sequence combining alternate saturation-recovery and inversion-recovery pulses. The resultant short time-to-inversion inversion-recovery and saturation-recovery images have been shown to be accurate in demonstrating the normal anatomy of the globe and orbit and for the demonstration of a wide range of disease states.

Abscess↗