Serum serotonin concentrations in dogs with degenerative mitral valve disease.

BACKGROUND: Increased serotonin (5HT) signaling has been implicated in valvular disease of humans and animals, including canine degenerative mitral valve disease (DMVD). High circulating 5HT concentration is a potential source of increased signaling, and serum 5HT concentrations have not been previously reported in dogs with DMVD. HYPOTHESIS: Dogs with DMVD and small breed dogs predisposed to DMVD have higher serum 5HT concentrations than large breed controls. ANIMALS: Fifty dogs affected with DMVD, 34 dogs predisposed to DMVD but without cardiac murmur or echocardiographic evidence of DMVD, and 36 healthy large breed control dogs. METHODS: Prospective analysis. Serum 5HT concentration was measured by an ELISA test. RESULTS: Median serum 5HT concentration was significantly higher in dogs with DMVD and in dogs predisposed to DMVD as compared with controls (DMVD, 765.5 ng/mL [interquartile range, 561.3-944.4]; predisposed, 774.9 ng/mL [528.3-1,026]; control, 509.8 ng/mL [320.8-708.8]; P= .0001). Subgroup analysis of predisposed dogs indicated significantly higher serum 5HT concentrations in Cavalier King Charles Spaniel (CKCS) dogs than in other breeds (CKCS, 855.0 ng/mL [635.8-1,088]; non-CKCS, 554.2 ng/mL [380.6-648.4]; P= .0023). Age, platelet count, and platelet morphology were not correlated with 5HT concentration in any group. CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs with DMVD had significantly higher serum 5HT concentrations when compared with large breed control dogs. Healthy CKCS dogs had significantly higher serum 5HT concentrations than other healthy dogs predisposed to DMVD. Additional investigation into a possible role of 5HT in the pathogenesis of DMVD is warranted.

Cerebral blood flow during migraine attacks without aura and effect of sumatriptan.

OBJECTIVE: To study regional cerebral blood flow (rCBF) during migraine attacks without aura and after treatment with sumatriptan. DESIGN AND INTERVENTION: We performed three technetium Tc99m hexemethyl-propyleneamineoxime single photon emission computed tomography scanning procedures in patients with migraine who participated in a double-blind, placebo-controlled, randomized clinical trial (1) outside an attack, (2) during an attack, and (3) after treatment of the attack with 6 mg of subcutaneous sumatriptan. SETTING: University hospital. PATIENTS: We studied 20 patients with migraine without aura, 15 of whom were evaluated under all three conditions and five of whom were evaluated under only two conditions. OUTCOME MEASURES: The single photon emission computed tomographic images were evaluated semiquantitatively with regard to (1) the degree of asymmetry of the rCBF between the headache side and the nonheadache side and (2) the ratio of the rCBF in regions of interest to the rCBF in two reference areas (cerebellum or frontal cortex). RESULTS: We found no significant rCBF asymmetries outside or during the attack or after treatment with sumatriptan, and there were no significant changes of the rCBF ratios during the attack (compared with outside the attack) or after treatment of the attack (compared with during the attack). CONCLUSION: Migraine attacks without aura and treatment of the attacks with 6 mg of subcutaneous sumatriptan are not associated with detectable focal changes of the rCBF.

Prospective comparative study of technetium-99m-WBCs and indium-111-granulocytes for the examination of patients with inflammatory bowel disease.

In a prospective comparative study of 14 patients with inflammatory bowel disease (IBD), the abilities of 99mTc-HMPAO labeled white blood cells (WBCs) and 111In-granulocytes to assess the presence and location of active disease were compared. The two examinations were carried out within 2 wk of each other. Scintigraphically concordant positive or discordant segments were evaluated by radiologic or endoscopic examination performed within 14 days. When bowel segments were compared, concordance was found for 102/111 (91.8%) segments between 99mTc-WBC images obtained at 1 hr after injection and 3-hr 111In-granulocyte images. For five of five 99mTc-WBCs positive/111In-granulocyte negative segments, it could be proven that the 99mTc-WBC result was caused by active disease. For patients, 99mTc-WBC scintigraphy detected four more patients with active disease than 111In-granulocytes (11 and 7 patients, respectively). Technetium-WBCs was superior in the assessment of active disease, especially for small bowel segments. We conclude that early imaging 1 hr after the injection of 99mTc-WBCs can reliably replace 111In-granulocyte scintigraphy in IBD patients because the radiopharmaceutical is available on a daily basis. Thus, there is less radiation burden to the patient and cell separation is simpler and less time-consuming.

Joint scintigraphy for quantification of synovitis with 99mTc-labelled human immunoglobulin G compared to histological examination.

OBJECTIVE: This study addressed the following questions: How does 99mTc-IgG scintigraphy compare to physical examination in the detection of synovitis as determined histologically, and is 99mTc-IgG scintigraphy a sensitive detector of histologically documented synovitis activity in the absence of clinically detectable knee joint swelling? METHODS: The results of measuring synovitis activity by physical examination and by scintigraphy with technetium-99m labelled polyclonal human immunoglobulin G (99mTc-IgG) were compared with the results of histological examination of synovial biopsies taken from the knee joints of patients with rheumatoid arthritis (n = 21), osteoarthritis (n = 9) and various other rheumatic diseases (n = 10). RESULTS: The sensitivity of 99mTc-IgG scintigraphy in detecting synovitis activity, as determined histologically (85%), was higher than the sensitivity of joint swelling (65%). In the absence of clinically detectable knee joint swelling the sensitivity of 99mTc-IgG scintigraphy was 83%. CONCLUSION: This study shows that 99mTc-IgG scintigraphy is a more sensitive method than physical examination in detecting histologically documented synovitis activity.

Evaluation of the lymph flow with lymphoscintigraphy after rotationplasty for the treatment of bone tumors.

We studied the cases of eleven patients in whom a rotationplasty had been done after wide resection of the distal part of the femur. All patients had had a malignant tumor of bone, but none had the complication of edema or leakage of lymph after the rotationplasty. We made lymphoscintiscans soon after the operation in four patients and weeks or months later in all eleven patients. There was a delay in the flow of lymph in three of the four patients who were examined lymphoscintigraphically soon after the operation and there was obstruction of flow in the fourth patient, but there was evidence of a decreased rate of flow in only two of the eleven patients at the time of the later examination.

Role of radionuclide ventriculography in evaluating cardiac function.

The role of nuclear cardiology techniques for evaluating cardiac function has become increasingly important among other diagnostic techniques. The current status of radionuclide imaging of left and right ventricular function allows accurate diagnosis of cardiac patients with both coronary and noncoronary disease. The combination of gated first-pass and equilibrium radionuclide ventriculography makes it possible to assess more completely cardiac function than by either technique alone. Of particular interest to most imaging physicians is the current position of exercise ventriculography in the diagnostic setting, especially since this test has undergone new scrutiny in its application to broader patient segments. This technique and issues related to its place in the diagnostic environment are discussed in this review article, with emphasis on relevance to the clinical laboratory.

Technetium-99m nanocolloid for the scintigraphic assessment of inflammatory bowel disease in the colon: its value in comparison with indium-111-labelled granulocytes.

The usefulness of 99mTc-nanocolloid for the assessment of localization and disease activity of colitis in patients suffering from inflammatory bowel disease (IBD) was investigated in 10 patients. Results of 99mTc-nanocolloid scintigraphy were compared with Indium-111 autologous granulocyte scintigraphy and the activity index according to Van Hees. In none of the patients a true positive result of the 99mTc-nanocolloid scintigraphy was encountered, while 111In-granulocyte scintigraphy was positive in 7 of 10 patients with active disease. Radioactivity became visible in the small bowel starting 2 h after injection of 99mTc-nanocolloid most likely because of excretion by the liver of degradation products of the radiopharmaceutical. The authors conclude that despite a previous communication 99mTc-nanocolloid cannot replace 111In-granulocytes for the assessment of IBD patients with active colitis.

The determination of relative kidney function in obstructive uropathy with 99Tcm-DMSA.

In this investigation differential kidney function studies were carried out for eight patients with obstructive uropathy and seven patients who did not suffer from obstruction. The aim of this investigation was to determine whether possible retention of 99Tcm-DMSA in the dilated system would lead to overestimation of the functional mass of an obstructed kidney. The clinical examination took place 4 and 24 h after i.v. injection of the 99Tcm-DMSA. From our results we conclude that this is not a major problem. It appeared that the 4 h values are as reliable as the 24 h values in the clinical situation.

Is radiolabelled sucralphate scintigraphy of any use in the diagnosis of inflammatory bowel disease?

Previous optimistic reports led us to undertake a study to determine the value of 99Tcm-sucralphate scintigraphy in the assessment of localization and extent of active inflammatory bowel disease. Eight patients were studied; four had Crohn's disease (three small bowel and one colon localization) and four patients had ulcerative colitis. The results obtained by scintigraphy were compared with those obtained by diagnostic radiology and/or endoscopy. In five patients indium-111 granulocyte scintigraphy was also performed. 99Tcm-sucralphate scans showed total discrepancy with standard investigations in four patients and partial discrepancy in the other four. Furthermore, it was difficult from the images to decide whether the radiolabelled sucralphate indicated true inflammation or normal distribution of the radiopharmaceutical. Patient acceptability was very low due to frequent scanning times and the recommended purgation which was not well tolerated and is contraindicated in severely ill patients. We conclude that this technique is not a good screening test for diagnosing inflammatory bowel disease and we have, therefore, discontinued the study.

99Tcm-labelled polyclonal human immunoglobulin G scintigraphy before and after intra-articular knee injection of triamcinolone hexacetonide in patients with rheumatoid arthritis.

The ability of 99Tcm-labelled polyclonal human immunoglobulin G (99Tcm-IgG) scintigraphy to monitor intra-individual variation in arthritis activity was studied in seven patients with rheumatoid arthritis (RA). These patients were treated with an intra-articular injection of 20 mg triamcinolone hexacetonide. The results of semiquantitative 99Tcm-IgG scintigraphy were compared with the degree of joint swelling and the histological changes observed in synovial biopsies before and 14 days after the injection. In all seven patients the local treatment resulted in a decreased arthritis activity of the treated knee as measured clinically or histologically. This decrease was parallelled, in all patients except one, by a lower uptake of 99Tcm-IgG after the injection when compared to uptake prior to treatment. This study shows that 99Tcm-IgG scintigraphy is able to reflect intra-individual variations in arthritis activity in patients with RA.

Is it possible to assess disease activity of inflammatory bowel disease with scintigraphy?

99mTc-HMPAO-leukocyte scintigrams were compared with the activity index (AI) of Van Hees in 145 inflammatory bowel disease (IBD) patients. Labelling of leukocytes with 99mTc-HMPAO was less time-consuming and less laborious than 111In-labelling of granulocytes; in addition, the radiation dose for the patient is lower and the shorter acquisition time allows multiple views. In a previous comparative study 99mTc-leukocytes proved superior to 111In-granulocytes in detecting active IBD. The present study shows that a positive AI (> 125) is associated with a positive 99mTc-leukocyte scintigram (40 pts); a negative 99mTc-leukocyte scintigram is only found in patients with a negative AI (27 pts). In 30 out of 78 patients with an AI < or = 125 and a positive scintigram these positive results were confirmed by radiological and/or endoscopic examinations, but in the remaining 48 patients verification of the scintigraphic result was prohibited due to the absence of other confirmative examinations within 1 month of scintigraphy. In our view 99mTc-leukocyte scintigraphy may well be the gold standard for functional assessment of inflammation intensity and localization in IBD patients.

Extraskeletal localization of 99mTc-labeled bone-seeking tracers in bone scintigraphy.

In this article clinical examples of extraskeletal localization of technetium-99m (99mTc)-labeled diphosphonate are described. In several of these cases this finding was relevant for clinical decision-making. 99mTc-labeled diphosphonates have been used for skeletal imaging since 1971, and from 1973 on many reports of extraskeletal localizations of these agents have been published. This visualization can be due to (1) an abnormality of the excretory route of 99mTc-labeled diphosphonate or (2) increased uptake in pathologically altered tissues and organs. The latter has been recorded in a multitude of disease processes, such as ischaemic injury, inflammatory processes, benign or malignant neoplasms, non-skeletal metastases, malignant pleuritis, scars, radiation injury and amyloidosis. Although the precise mechanism of extraskeletal uptake of 99mTc-labeled diphosphonate remains uncertain, binding of this radiopharmaceutical to calcium-containing compounds is thought to play a critical role.

Intraoperative detection of carcinoid tumor of the ovary by gamma probe.

PURPOSE: To demonstrate the detection of carcinoid tumor of the ovary by gamma probe during surgery in a patient in whom the exact location of a metastatic tumor was uncertain. METHODS: Twenty-four hours after injection of 350 MBq (9.5 mCi) I-123, an anterior image of the abdomen was acquired before surgery to demonstrate MIBG accumulation. Holding the ovary in the hand during the operation, a surgical gamma probe indicated the exact location of highest radioactivity. RESULTS/CONCLUSIONS: Intraoperative MIBG scanning is a useful noninvasive detection method to localize metastases of carcinoid in the ovary. This method should be used only when it is not clear where the area of increased activity is located in the body because there are certain costs involved.

Value of indium-111 tropolonate autologous granulocyte scintigraphy in the assessment of inflammatory bowel disease.

Indium-111 autologous leucocyte scanning is a non-invasive and reliable technique for the detection of abdominal abscesses. In the past decade several papers have been published concerning the use of this technique in the assessment of inflammatory bowel disease (IBD) with variable results. We conducted a prospective study of 62 patients with IBD attending the Leiden University Hospital, to assess the diagnostic value of indium-111 tropolonate autologous granulocyte scanning. Fifty-one patients had Crohn's disease (CD) (30 with involvement of the small bowel, 18 the colon only, and 3 patients had both localizations), and 11 had ulcerative colitis (UC). Twenty-one of 26 patients with evidence of active disease of the small intestine had a true-positive scan (sensitivity, 80%). However, accurate assessment of localization and extent of disease were often difficult. The other five patients had a false-negative scan. Seven patients had a true-negative scan. No false-positive scans were found. Thus, the diagnostic accuracy for small-intestinal Crohn's disease was 85%. In contrast, of 32 patients with colonic disease (CD and UC), 26 had a true-positive scan corresponding in localization and extent with standard investigations, 3 patients had a false-negative scan (sensitivity, 90%), and 3 had a true-negative scan (diagnostic accuracy, 91%). The patients' acceptability of this procedure was definitely superior to that for radiology and endoscopy. In conclusion, this technique has a definite place in evaluating localization and extent of active colonic disease and in severely ill patients in whom invasive techniques are contraindicated.(ABSTRACT TRUNCATED AT 250 WORDS)

A retrospective evaluation of doxorubicin-based chemotherapy for dogs with right atrial masses and pericardial effusion.

OBJECTIVE: To report the outcome of doxorubicin-based chemotherapy as the sole treatment for dogs with echocardiographically identified right atrial masses and pericardial effusion. METHODS: A retrospective study of case records of dogs with right atrial masses treated with doxorubicin. Dogs were excluded from the study if they had any type of surgery performed such as pericardiectomy or right atrial mass resection, or if their chemotherapy protocol did not include doxorubicin. The data collected included signalment, history, physical examination findings, diagnostic test results and long-term survival. RESULTS: Dogs with right atrial masses and pericardial effusion that received doxorubicin-based chemotherapy alone had a median survival of 139 · 5 days (range 2 to 302 days). Chemotherapy side effects were frequent but mild. CLINICAL SIGNIFICANCE: Doxorubicin-based chemotherapy alone appears to be a viable treatment option for dogs with echocardiographically identified right atrial masses and pericardial effusion.

Bone scintigraphy in oncology: an update with emphasis on efficacy and cost-effectiveness.

Bone scintigraphy has been helpful to oncologists in the initial evaluation and diagnostic follow-up of patients with primary and secondary neoplasms. This review discusses this way of bone imaging with respect to the choice of the bone seeking radiopharmaceutical and puts emphasis on its diagnostic yield and cost-effectiveness in various malignant diseases.