Radionuclide assessment of diastolic function in aortic regurgitation: a critical study of its measurement.

Systolic and diastolic ventricular function was assessed in patients with aortic regurgitation as the peak ejection and filling rates. The measured rate of change of volume was related to the ejection fraction when expressed in end diastolic volumes per second (EDV.s-1) but not when expressed as stroke volumes per second (STV.s-1) suggesting that an apparent variation in left ventricular volume change when expressed as EDV.s-1 may occur as a result of an increase in end diastolic volume rather than any absolute alteration in filling rate. There was a significantly greater increase in peak filling than peak ejection rate with increasing heart rate in patients with aortic regurgitation, and this relation was exaggerated compared with that in controls. No definite difference in these indices of left ventricular function was found in patients with aortic regurgitation of severity varying from mild to severe. Isolated measurements of left ventricular filling rate may not accurately reflect left ventricular compliance since other factors, particularly heart rate, must be considered.

Radionuclide studies in intestinal transplantation. Diagnosis of rejection and assessment of permeability.

Three patients who received intestinal allografts were studied using two distinct radionuclide investigations. In the first, 111In or 99mTc-labeled leukocyte scanning was performed to assist in the diagnosis of rejection. It was able to demonstrate the occurrence of rejection in the transplanted intestine, and the response to antirejection therapy. In 1 case, the abnormality on the scan preceded the histological confirmation of rejection. The second technique studied mucosal integrity by serial 51Cr-EDTA/14C-mannitol permeability tests. These studies demonstrated the initial marked impairment and the slow return to normal function of the intestinal mucosal barrier. In 1 patient, this occurred by 91 days; in another, it took 232 days. A single assay performed in the third patient at the time of allograft rejection was also abnormal. Both radionuclide tests were helpful in the care of these complicated cases.

Technetium (99mTc)-labelled white cell scanning, 51Cr-EDTA and 14C-mannitol-labelled intestinal permeability studies: non-invasive methods of diagnosing acute intestinal graft-versus-host disease.

We describe a case of a 38-year-old female who presented with diarrhoea and abdominal pain 27 days after a second 'top-up' allogeneic marrow infusion for acute myeloid leukaemia (AML) in first remission. A clinical diagnosis of gut graft-versus-host disease (GVHD) was made. Technetium (99mTc)-labelled white cell scanning and intestinal permeability studies using 51Cr-EDTA and 14C-mannitol were undertaken to confirm the diagnosis. The 99mTc white cell scan showed extensive uptake in the small bowel and the urinary excretion of 51Cr-EDTA was increased, the results being consistent with intestinal inflammation and gut GVHD. 99mTc white cell scanning and intestinal permeability studies may assist in the diagnosis of gut GVHD and in assessing its extent and response to treatment.

Isotopic scanning of bone in the diagnosis of osteomalacia.

Results of a study performed over 18 months in 21 elderly patients showed that isotopic bone scanning is a sensitive technique for the detection of osteomalacia. It can be used not only to indicate the presence of the disease but the response to treatment.

Accuracy of serology for the diagnosis of Helicobacter pylori infection--a comparison of eight kits.

AIMS: To determine the accuracy of eight commercially available kits for the serological diagnosis of Helicobacter pylori infection, and hence whether a serology service could be introduced to reduce endoscopy workload. METHODS: Eighty four patients newly presenting to their general practitioners with dyspepsia were recruited. Gold standard diagnosis of H pylori infection was obtained both by a histological examination of gastroduodenal biopsy specimens and by the 14C-urea breath test (UBT). The performance of six quantitative and two qualitative enzyme linked immunosorbent assays for H pylori IgG, used according to the manufacturers' instructions, with serum samples obtained during the endoscopy visit, were compared. RESULTS: The study population had a median age of 45 years, and the prevalence of H pylori infection was 35%. With one exception, where the patient had received a course of anti-H pylori treatment between endoscopy and UBT, there was 100% concordance in the results of the two gold standard techniques. Discordant serology results were more common in patients aged > 50 years (42% of the total) than in younger patients (21%), and this was most noticeable in uninfected patients. The sensitivity of the kits was good (90-100%), but specificity was more variable (76-96%), and the rate of equivocal results was unacceptably high in some cases (0-12%). The overall accuracy of the kits ranged from 83 to 98%. Two kits in particular performed well (Pylori-Elisa II, Bio-Whitaker and Premier, Launch; qualitative) with 98% and 100% accuracy, respectively. CONCLUSIONS: In a symptomatic population with a prevalence of H pylori infection of 35%, particularly in patients aged < 50 years, some but not all serology kits may be used as a highly accurate and inexpensive alternative to the gold standard techniques.

Management of systemic vasculitis: contribution of scintigraphic imaging to evaluation of disease activity and classification.

The use of radio-isotope-labelled leucocyte scans has become established as a non-invasive and accurate means of diagnosing a variety of inflammatory conditions. We report a retrospective study on leucocyte imaging in the management of 50 patients with systemic vasculitis. Leucocyte imaging was useful for detecting unsuspected sites of disease and monitoring disease activity. Scintigraphy was superior to conventional radiography or CT scanning for detecting and monitoring vasculitic involvement of the respiratory tract. The scans were useful for differentiating between Wegener's granulomatosis (WG) and microscopic polyangiitis (MPA). There was a close and statistically significant relationship between the clinical diagnosis of WG and nasal uptake on leucocyte scans (p < 0.01), whereas in patients with MPA it was rare. Anti-proteinase 3 autoantibody specificity correlated significantly with nasal uptake of labelled leucocytes (p < 0.03). Leucocyte imaging is a useful non-invasive investigation in patients with systemic vasculitis.

Cerebral vasculitis--recognition, diagnosis and management.

Cerebral vasculitis is a serious but uncommon condition which presents considerable difficulties in recognition, diagnosis and treatment. We studied eight consecutive patients in whom this diagnosis was made. Despite the great diversity of symptoms and signs, we noted three clinical patterns: (i) acute or sub-acute encephalopathy, (ii) a picture with some similarities to multiple sclerosis ('MS-plus'), and (iii) features of a rapidly progressive space-occupying lesion. The identification of these patterns may help recognition of cerebral vasculitis. The diagnostic value of four investigative procedures not previously studied in cerebral vasculitis was assessed: ophthalmological examination using low-dose fluorescein angiography with slit-lamp video microscopy of the anterior segment (abnormal in 4/5 patients); spinal fluid oligoclonal band analysis (abnormal in 3/6 patients); anti-neutrophil cytoplasmic antibody assay (abnormal in 3/8 patients); and indium-labelled white-cell cerebral imaging (positive in only one patient). Treatment was with steroid alone (n = 2) or steroid with cyclophosphamide (n = 6). Seven patients responded clinically.

Reduced faecal blood loss in patients receiving choline magnesium trisalicylate ('Trilisate') when compared with aspirin.

A study was carried out in 16 healthy male volunteers to compare the effects on faecal blood loss of comparable daily doses of choline magnesium trisalicylate (3 g) and acetylsalicylic acid (2.4 g) given over a period of 7 days. Faecal blood loss was measured by 51Cr labelling of red cells. Haematological parameters were also monitored. Faecal blood loss and the reduction in haemoglobin levels were significantly less in the choline magnesium trisalicylate group than in the acetylsalicylic acid group. No significant differences were detected in the partial thromboplastin time, prothrombin time or bleeding time in either group.

Role of lacrimal scintigraphy and subtraction macrodacryocystography in the management of epiphora.

Fifty-one patients were investigated by subtraction macrodacryocystography (SMDCG, 103 systems) and by lacrimal scintigraphy (LS, 105 systems). It was found that these investigations complemented each other and between them the precise site of obstruction in the lacrimal drainage apparatus could be determined in 80%. The radiation dosage to the lens in SMDCG significant, and it is therefore recommended that the patients with lacrimal obstruction should: (1) have lacrimal puncta dilated with a probe to No. 1 diameter and be forbstruction is still uncertain, then and only then should SMDCG be performed.

Does Fourier phase shift correlate with conduction delay in bundle branch block?

Fourier analysis of radionuclide ventriculography is adept at qualitatively demonstrating interventricular conduction delay in bundle branch block. In this study of eighteen patients, there is a considerable individual variation when the phase delay is expressed as an absolute conduction delay (milliseconds). Much of this variability persists after curve representation by the Fourier function has been optimized. It is suggested that this variability is due to differences in the shape of the right and left ventricular time-activity curves, reflecting differences in contraction and relaxation in the two ventricles. Such differences may be more pronounced in some subjects than others. These results suggest that absolute conduction delay cannot be reliably achieved by this method.

Skeletal muscle weakness and dysphagia caused by acid maltase deficiency: nutritional consequences of coincident celiac sprue.

BACKGROUND: A 30-year-old woman with celiac sprue had progressive weight loss, myalgia, limb-girdle weakness, and dysphagia. METHODS AND RESULTS: Barium swallow showed an atonic esophagus, and scintigraphic study confirmed esophageal dysmotility. Skeletal muscle biopsy showed characteristic appearances of acid maltase deficiency, which was confirmed by a reduction of leukocyte acid alpha-glucosidase activity. CONCLUSIONS: Nutritional factors may have accelerated the presentation of the lysosomal storage disorder. This is the first reported case of dysphagia caused by esophageal motor weakness in acid maltase deficiency.

Short communication: venous uptake of 99Tcm-MIBI during resting cardiac imaging: incidence and the effect of using a flush.

99Tcm-methoxy-isobutyl-isonitrile (99Tcm-MIBI) is taken up by the vein through which it is injected in some individuals. We prospectively analysed technical and clinical factors that may be associated with this uptake. Imaging was performed over 1 h after injection so excluding a blood pool effect. The frequency of uptake could be reduced from 25.9% to 4.2% by using a 20 ml saline flush (p < 0.05). Other factors appeared irrelevant. The presence of venous uptake did not affect myocardial counting statistics but, if unrecognized, it could cause confusion in studies of the neck or chest that use 99Tcm-MIBI.

Technetium 99m methylene diphosphonate scanning in Thompson hemiarthroplasties.

Fourteen patients who had had Thompson hemiarthroplasties at least ten months previously were scanned using 555 MBq (15mCi) 99Tcm methylene diphosphonate. No hips were infected, the control group of eight firmly fixed prostheses showed a weak diffuse uptake pattern whilst five of six patients with loose prostheses showed a characteristic focal distribution of increased uptake.

Selenomethionine liver scanning in the diagnosis of hepatoma.

Liver subtraction scans using 99Tcm sulphur coloid and 75Se-selenomethionine were carried out in 58 patients with suspected hepatoma. Of the 18 patients with hepatoma proven by histology, 16 showed selective concentration of selenomethionine in the tumour, giving a true positive rate of 89%. Of the 40 patients who did not have hepatoma, 32 scans showed no evidence of selective concentration of selenomethionine, giving a true negative rate of 80%. The false positive rate was 8% in non-cirrhotic patients with focal disease, but 55% in patients with cirrhosis. It is concluded that combined scanning with this technique is useful in non-cirrhotic patients in distinguishing hepatoma from other causes of focal disease, but that the technique is not useful and frequently misleading in patients with cirrhosis.

High renal activity on bone scintigrams. A sign of hypercalcaemia?

Various abnormalities of the renal tract can be detected from the renal images seen on 99Tcm methylene diphosphonate (MDP) bone scintigrams. Diffusely increased renal parenchymal activity has been associated with cytotoxic and other drug therapy, radiation nephritis, iron overload and cirrhosis. A further association--with hypercalcaemia--is reported here. In a retrospective study, 1950 bone scintigrams were reviewed and a significant relationship between high renal activity and hypercalcaemia was found. This was subsequently confirmed by a small prospective study. None of the patients whose bone scintigrams showed this association had evidence of nephrocalcinosis on X rays. It is postulated that in these hypercalcaemic patients there may be high tissue calcium in the kidneys which results in the high uptake of MDP, and it is suggested that serum calcium be measured in patients with previously unsuspected hypercalcaemia whose bone scintigrams exhibit the finding of high parenchymal renal activity.

Can 99Tcm HMPAO leucocyte scintigraphy distinguish between Crohn's disease and ulcerative colitis?

This paper has retrospectively analysed the ability of 99Tcm HMPAO leucocyte scintigraphy to distinguish Crohn's disease from ulcerative colitis. The diagnostic criteria were established by reviewing 99Tcm HMPAO leucocyte scintigrams in 123 patients with histologically proven Crohn's disease (83) or ulcerative colitis (40). Uptake in the right iliac fossa with or without other segments of colon, irregular bowel uptake, small bowel uptake or colonic activity with rectal sparing were all strongly suggestive of Crohn's disease. Left sided colitis was found to indicate ulcerative colitis. Total colitis occurred in both ulcerative colitis and Crohn's disease. The criteria were later tested in an additional 62 patients with excellent results (accuracy 98%). In 63 patients in whom the results of barium radiology were also available, the accuracy of scintigraphy was higher (93% and 83%, respectively). We conclude that 99Tcm HMPAO leucocyte scintigraphy can accurately distinguish between Crohn's disease and ulcerative colitis in a large proportion of cases and appears to be more reliable than conventional radiology.

The use of a chelating derivative of alpha melanocyte stimulating hormone for the clinical imaging of malignant melanoma.

A novel chelating derivative of alpha melanocyte stimulating hormone, bis MSH-DTPA, has been used for the diagnostic targeting of malignant melanoma. 15 patients were investigated of whom nine were shown by other means to have active disease at the time of the scan. Tumours were imaged in all of these nine patients. Of a total of 46 lesions over 10 mm encountered, 41 (89%) were imaged. There were no false positives and in two cases bisMSH-DTPA was instrumental in reversing diagnoses made using ultrasound. Derivatives of melanocyte stimulating hormone may be of considerable value in targeting melanomas.

The significance of low grade right iliac fossa uptake on 99Tcm-HMPAO labelled white cell scans.

Technetium-99m HMPAO labelled white cell scanning is now an accepted method for assessing the activity of inflammatory bowel disease. However, false positive results have been demonstrated. This study was conducted to assess the significance of low grade uptake on 99Tcm-HMPAO labelled white cell scans in the right iliac fossa (RIF) in the context of possible inflammatory bowel disease (IBD). 32 patients over a period of 1 year had low grade RIF uptake as the predominant abnormality. 20 of these had no prior diagnosis of inflammatory bowel disease. Only one case in this group was subsequently diagnosed as having Crohn's disease. Nodular lymphoid hyperplasia (NLHP) and non-steroidal anti-inflammatory drugs (NSAIDs) were also associated with low grade RIF uptake. Possible explanations for these findings are discussed.

Validation of 99Tcm-HMPAO leucocyte scintigraphy in ulcerative colitis by comparison with histology.

Leucocyte scintigraphy offers an alternative to more invasive techniques in the investigation of inflammatory bowel disease. The accuracy of 99Tcm-HMPAO leucocyte scintigraphy has not been assessed by comparison with colonic histology, which was the aim of this study. 15 patients with ulcerative colitis underwent 99Tcm-HMPAO leucocyte scintigraphy (TLS) less than 5 days before colonoscopy. Histological features of mucosal biopsies were compared with total and segmental colonic TLS scores. Segmental and total scintigraphy scores correlated most strongly with histological grades for acute inflammation (r = 0.75, p < 0.001 and r = 0.9, p < 0.001, respectively) and chronic inflammatory cell infiltration in the lamina propria (r = 0.76, p < 0.001 and r = 0.86, p < 0.001, respectively). 99Tcm-HMPAO leucocyte scintigraphy detected acute inflammation in the colon of patients with ulcerative colitis with a sensitivity of 91% and negative predictive value of 80% and localized acute inflammation to a particular colonic segment with a sensitivity of 82%, specificity of 94%, accuracy of 88%, positive predictive value of 94% and negative predictive value of 91%. 99Tcm-HMPAO leucocyte scintigraphy positivity predicts and localizes colonic acute inflammation with a high degree of confidence, but negative scintigraphy does not exclude acute inflammation.

The use of 99Tcm-DTPA aerosol ventilation scintigraphy in the diagnosis of pulmonary embolism.

Pulmonary scintigraphy is now established as a sensitive and noninvasive method for diagnosing pulmonary embolism (PE). The diagnostic specificity is increased if the perfusion study is combined with assessment of regional ventilation. The latter is usually performed using radioactive gases, either 133Xe or 81Krm, but these have some disadvantages. We report here a method for ventilation scintigraphy using 99Tcm-DTPA aerosol, previously described for the measurement of lung permeability, and present our findings in 20 patients. The system is easy to use and six-view images obtained can be readily compared with perfusion images. No data processing is required and any hospital with gamma camera facilities can use the system. Thus patients with suspected PE can have combined V/Q scintigrams to establish the diagnosis of PE and unnecessary treatment can be avoided.