Evaluation of renal function following treatment with 5-aminosalicylic acid derivatives in patients with ulcerative colitis.

BACKGROUND: A number of cases of nephrotoxicity have been reported in patients with inflammatory bowel disease taking oral 5-aminosalicylic acid (5-ASA). AIM: To evaluate the effects of 9 months of therapy with mesalazine or olsalazine on renal function in patients with ulcerative colitis in remission. METHODS: Forty patients with ulcerative colitis in complete remission for 6 months were randomized to either olsalazine (n=20) or mesalazine (n=20 for nine months). Thirty-six of the 40 patients were on prior salicylate therapy. Disease activity was the measure ofclinical efficacy and was assessed by the Harvey-Bradshaw Index (HBI). Laboratory efficacy measurements included glomerular filtration rate (GFR), microalbuminuria, urinary gluthathione S-transferase (GST) and serum C-reactive protein (CRP). Safety analysis consisted of documentation of adverse events and laboratory values. RESULTS: There was no significant reduction in the GFR overall on therapy. The levels of GFR adjusted for baseline were similar in the two treatment groups after 3, 6 and 9 months. A significantly higher percentage of mesalazine-treated patients experienced drug related adverse events, all of a minor nature. The incidence of adverse events causing early withdrawal was similar in the two treatment groups. CONCLUSION: Treatment with mesalazine or olsalazine for 9 months had no significant impact on GFR.

Classification of mild Alzheimer's disease by artificial neural network analysis of SPET data.

An evaluation of the performance of artificial neural networks (ANNs) for the classification of probable Alzheimer's disease (pAD) patients was undertaken using data extracted from four regions of interest constructed on single photon emission tomographic (SPET) cerebral perfusion images. Two studies using feed-forward neural networks (FFNNs) were undertaken. The first was to determine if it would be possible to classify pAD patients and normal subjects in a mixed group, comprising 29 patients diagnosed as having pAD varying in severity from mild, established dementia to moderate dementia and 10 healthy control subjects. The second was to determine if the networks generated in the first study could prospectively classify 15 additional patients with very mild or mild cognitive impairment. The results were compared to those obtained using the same data and discriminant analysis. The relative performances of the two analysis techniques were assessed on the basis of the area under receiver operating characteristics (ROC) curves. The FFNN successfully classified all datasets in the first study, achieving an area under the ROC curve of 1.00, whereas discriminant analysis achieved 0.94. When tested on data from the second group, the areas under the ROC curves varied between 0.86 and 1.00 for the FFNN, whereas that for discriminant analysis was 0.99. We conclude that FFNNs can accurately classify pAD patients with mild to moderate dementia using data obtained from SPET cerebral perfusion images.

Dose reduction in double contrast barium enema by use of low fluoroscopic current.

Under standard conditions double contrast barium enema (DCBE) was carried out on a selected patient cohort using either standard (1.5 mA) or low (0.5 mA) fluoroscopic current. A statistically significant (p < or = 0.01) reduction in total dose was achieved by use of low screening current. This reduction was of the order of 40%. Fluoroscopic image quality was analysed both objectively and subjectively, and was found not to be significantly degraded when the lower current was used. On blinded evaluation all examinations were found to be of diagnostic quality. The use of low fluoroscopic current results in a reduction in patient dose, without compromising fluoroscopic image quality or diagnostic standard of the examination. Low fluoroscopic current technique has been adopted as the standard in our department.

Somatostatin and somatostatin analogues in medullary thyroid carcinoma.

Medullary thyroid carcinoma (MTC) is a neuroendocrine tumour characterized by the production and secretion of calcitonin. MTC tumours may express functional somatostatin receptors (hSSTR). A significant proportion of hSSTR receptor-positive MTC tumours, including metastatic disease, may be visualized in vivo through 111In-pentetreotide scintigraphy. Four patients with recurrent/metastatic disease, who had previously been assessed with 111In-anti-CEA monoclonal antibody fragment [F(ab')2] imaging, were evaluated. 111In-pentetreotide scintigraphy localized all known disease sites. Furthermore, mediastinal disease was detected in one patient with negative conventional, and 111In-anti-CEA F(ab')2 imaging studies. The detection of somatostatin within the tumour (2 patients), or negative octreotide challenges (2 patients), did not affect the outcome of 111In-pentetreotide scintigraphy. In conclusion, 111In-pentetreotide scintigraphy appears at least as effective as 111In-anti-CEA F(ab')2 imaging and should be considered in the diagnostic evaluation of MTC, particularly in the setting of recurrent/metastatic disease not detected by conventional means.

Event-related potential prolongation in Alzheimer's disease signifies frontal lobe impairment: evidence from SPECT imaging.

BACKGROUND: The N2 and P3 components of auditory event-related potentials (ERPs) and single-photon emission computed tomographic (SPECT) images are separate independent biological markers of cerebral function and are abnormal in Alzheimer's disease (AD). The relationship between ERP N2 and P3 latencies and regional cerebral perfusion abnormalities in AD is unknown. METHODS: ERP and SPECT data were obtained one week apart in 18 patients with "probable" AD of mild or moderate severity, and 12 healthy age-matched elderly controls. Average premotor frontal, anterior temporal, inferior parietal, and occipital cortical/cerebellar perfusion ratios were calculated from the SPECT data and correlations with ERP N2 and P3 latencies derived for AD and control groups separately. RESULTS: ERP N2 latency was correlated significantly with the average frontal perfusion ratio (r = -.59; p < .009), but correlations with average temporal, parietal, and occipital ratios were nonsignificant in the AD group. Similarly, ERP P3 latency was correlated significantly with the average frontal perfusion ratio (r = -.65; p < .004), but not with the other perfusion ratios in the AD group. In the control group, a partial correlation between the average frontal perfusion ratio and the ERP N2 latency was noted (r = -.52; p < .09), but no other ERP/SPECT correlations approached statistical significance. CONCLUSION: ERP N2 and P3 latency delay in AD is a function of differential frontal lobe hypoperfusion.

Lymphatic obstruction in rheumatoid arthritis.

We describe four patients with rheumatoid arthritis and unilateral upper limb oedema. In all cases, qualitative lymphoscintigraphy showed lymphatic obstruction in the affected limb.

Gastric motility following oesophagectomy.

The motility of the vagally denervated transposed stomach after oesophagectomy was examined by ambulatory gastric manometry and videofluoroscopy. Two groups of subjects were studied. Group 1 comprised ten patients who had undergone oesophagectomy 6-12 months previously and group 2 consisted of six normal control subjects. Studies were performed on fasting and fed subjects, and following injection of erythromycin 8 mg/kg. No distinguishable manometric wave activity was seen in either group while fasting. Feeding generated a measurable wave pattern in the patient group only. A significant increase in the mean (s.e.m.) distal wave amplitude was identified after infusion of erythromycin in both patients (34.0(15.1) versus 12.2(3.1) mmHg, P < 0.05) and controls (15.1(3.4) versus 5.0(0.0) mmHg, P = 0.05). The response to erythromycin was more rapid in patients than in controls (mean(s.e.m.) 113(16) versus 377(133) s, P < 0.05) and the effect persisted for longer (more than 1 h) in those who had undergone oesophagectomy. Videofluoroscopy confirmed purposeful motility in both the normal and vagally denervated stomach. It is concluded that the transposed stomach is a dynamic conduit. Enhancement of motility was greatest in the denervated stomach, indicative of denervation supersensitivity.

The discriminant value of semiquantitative SPECT data in mild Alzheimer's disease.

UNLABELLED: In most semiquantitative SPECT studies, overlap between groups of patients with Alzheimer's disease (AD) and age-matched elderly controls is such that single posterior cortical perfusion measurements lack sensitivity. In the present study, the value of a combination of semiquantitative temporoparietal SPECT parameters was examined. METHODS: Supratentorial transaxial perfusion measurements were obtained in frontal, anterior temporal, posterior temporoparietal and occipital cortical areas in both hemispheres, in a baseline population of 10 healthy elderly controls and 30 mild to moderately impaired AD patients, as well as in a prospective group of 15 patients with mild cognitive impairment, 12 patients with a diagnosis of probable AD and individual cases of multi-infarct dementia, dementia-frontal type and paranoid psychosis. A linear discriminant function (LDF) was calculated from the baseline subjects' data to classify control and AD subjects individually. RESULTS: Highly significant hypoperfusion was noted in both the anterior temporal and posterior temporoparietal regions of interest in the AD group compared with controls, but with significant overlap. Using an LDF incorporating these perfusion measurements in both hemispheres, 10/10 (100%) controls and 26/30 (87%) AD baseline subjects were correctly classified. Using the baseline LDF in the prospective 15 mildly impaired cases, 11/12 new mild AD cases and none of the 3 non-AD cases were classified in the AD group. CONCLUSION: These results support the use of a combination of semiquantitative SPECT perfusion estimates from cortical areas with predictable pathological involvement in AD in a linear discriminant format in the clinical assessment of patients with suspected AD.

Scintigraphic imaging of small-cell lung cancer with [111In]pentetreotide, a radiolabelled somatostatin analogue.

Recent work suggests that between 50 and 75% of small-cell lung cancer (SCLC) tumours have specific high-affinity binding sites for somatostatin. This study evaluated the potential role of the radiolabelled somatostatin analogue, [111In]pentetreotide, in the detection and staging of SCLC in patients prior to and after chemotherapy using scintigraphic imaging techniques. Thirteen patients were studied prior to chemotherapy. Following standard staging six patients had limited stage disease and seven extensive disease. [111In]pentetreotide imaging led to the detection of all primary sites of disease, including a primary site of disease not detectable with chest radiograph or computerised tomography (CT) of the thorax. Five of ten metastatic sites detected by standard staging were also imaged. Furthermore, a cerebellar metastasis was detected in a patient thought to have disease confined to the right hemithorax. This was subsequently confirmed with a CT brain scan. Following chemotherapy [111In]pentetreotide imaging detected residual intrathoracic disease in two of three patients with complete remissions by standard staging and in two patients who had had a partial response to chemotherapy. These results suggest that [111In]pentetreotide imaging may have a role to play in the clinical evaluation of patients with SCLC. Specifically, this technique may be of particular value in detecting residual intrathoracic disease in patients thought to be in complete remission by conventional staging methods.

Imaging of bronchial carcinoid tumours with indium-111 pentetreotide.

Neuroendocrine tumours are characterised by the expression of high affinity binding sites for somatostatin. The detection of bronchial carcinoid tumours through scintigraphic imaging is described in two patients using the novel radiolabelled somatostatin analogue indium-111 pentetreotide.

Image processing of videofluoroscopy of patients with velopharyngeal insufficiency and hypernasal speech.

Eleven patients with hypernasal speech and velopharyngeal insufficiency (VPI), together with five normals, were evaluated by videofluoroscopy to assess velopharyngeal movement, velar lift and lateral pharyngeal wall movement. Computer processing of the images obtained was used to compensate for initial poor quality images by contrast and edge enhancement techniques and to provide objective measurement of the movements involved. It was demonstrated that objective computer aided analysis of videofluoroscopic images is feasible and may provide additional subtle diagnostic information when nasendoscopy is unavailable. In addition, results obtained showed an increased degree of velar lift and lateral pharyngeal wall movement for the more severely affected patients. These suggest a compensatory mechanism in operation for the more severe cases of VPI.

Erythromycin improves emptying of the denervated stomach after oesophagectomy.

Oesophagectomy, necessitating vagotomy, is associated with delayed gastric emptying. Cisapride and erythromycin have prokinetic effects and improve emptying of the innervated stomach. Their effect on the denervated stomach following oesophagectomy is unknown. The effect of pyloroplasty, cisapride and erythromycin on the rate of gastric emptying after oesophagectomy was studied using a radiolabelled meal. Oesophagectomy was associated with a marked delay in gastric emptying (56 per cent of the test meal remaining after 4 h) compared with age- and sex-matched normal controls (16 per cent; P < 0.001). Erythromycin improved the rate of gastric emptying to preoperative control values (18 per cent). Cisapride had no significant effect on gastric emptying. After pyloroplasty, 32 per cent of the label remained at 4 h (P = 0.065). The mean(s.e.m.) half-emptying time in patients receiving erythromycin was 94(29) min, which was similar to control values, 55(3) min (P = 0.26). Erythromycin may have a role in the treatment of gastric stasis following oesophagectomy or truncal vagotomy.

Imaging of medullary carcinoma of the thyroid using 111In-labelled anti-CEA monoclonal antibody fragments.

The distribution of 111In-labelled anti-carcinoembryonic antigen (CEA) monoclonal antibody fragments [F(Ab')2] was studied in five patients either with known inoperable medullary carcinoma of the thyroid (MCT) or evidence of recurrence/metastases based on elevated calcitonin (hCT) levels. All five cases had elevated serum CEA levels and positive immunohistochemical stains for both hCT and CEA prior to scintigraphy. In two patients with identified inoperable disease both planar and SPECT scans were positive. In the remaining three patients, where the recurrence/metastatic sites were unknown, SPECT images were positive in two. Of these, only one had positive planar images. These results indicate that 111In-labelled anti-CEA F(ab')2 scintigraphy, especially in conjunction with SPECT, is useful for the diagnostic evaluation of patients with MCT. The limiting factor of this technique is the high level of non-specific uptake, particularly in the liver, but improvements in the specificity of newer anti-CEA antibodies and the ability to label these with 99Tcm is addressing this problem.

Osteoarthrosis in runners with knee pain.

A clinical and radiological study of the knee joints of twenty middle and long distance runners, complaining of knee pain, was carried out. Osteoarthrosis of varying degree was found in six of the runners. A torn meniscus requiring surgery was found in one athlete, and another had considerable ligamentous laxity - both of these conditions predispose to the development of degenerative changes. Degenerative changes were significantly associated with the presence of genu varum (p less than 0.01) and history of severe injury (p less than 0.05). The number of years spent training was significantly greater in the affected group than in the unaffected group (p less than 0.05).

Low-dose radioisotope scanning and quantitative analysis in the diagnosis of congenital hypothyroidism.

Quantitative thyroid scanning using low doses of 99mTc sodium pertechnetate (1.85-3.7 MBq) was performed in 38 cases of congenital hypothyroidism. Of these 38 cases, 29 were scanned at 14 +/- 6 days old, and 9 at 1 year old. The scans show the full range of gland anatomy from athyreotic to normal. All morphologically normal scans had grossly increased uptakes of 99mTc. The incidence of the various thyroid anatomies was different in each age group. The average radiation dose to the thyroid was 2.29 mGy, with at least 70% of patients receiving a dose of 3.0 mGy or less. Such low doses of 99mTc should allow further scanning in later life. Neonatal thyroid scanning reveals the aetiology of congenital hypothyroidism and enables the clinician to assess the short- and long-term needs of the child.

An assessment of dynamic gastric scanning with 99Tcm-pertechnetate.

Following intravenous injection, technetium-99m (99Tcm) is selectively taken up by the stomach, and this uptake, which is stimulated by pentagastrin, may be quantified using a gamma camera. Using this property of 99Tcm as a means of assessing gastric function, we found that the mean rate of 99Tcm uptake was significantly greater in 24 duodenal ulcer patients than in 10 healthy controls (P less than 0.01). Scanning values did not correlate with BAO of MAO which were measured on a separate day. Both vagotomy (n = 10) and cimetidine infusion (n = 5) significantly reduced the rate of uptake of 99Tcm (P less than 0.01). Thus, although 99Tcm reflects a function of the stomach which is similar to acid secretion, scanning did not give a good estimate of acid secretion in this group of subjects.