Case report: renal scintigraphy in the diagnosis of urinary extravasation.

Renal scintigraphy is a sensitive method for disclosing urinary extravasation. Its role following a road traffic accident is clearly presented in this case report. It is concluded that such a study can fill an important gap between the clinical and intravenous urography assessment and the more invasive studies in trauma victims.

Imaging modalities and low back pain: the role of bone scintigraphy.

The role of bone scintigraphy, both planar and single photon emission tomography (SPET), in investigating cases of chronic back pain is assessed in conjunction with other imaging modalities. A review of the literature was undertaken and an imaging strategy is suggested. It is concluded that bone scintigraphy has an important role as an imaging modality in investigating cases of chronic low back pain.

The role of bone scintigraphy and other imaging modalities in knee pain.

The role of bone scintigraphy (planar and SPET) in the investigation of chronic knee pain is assessed in conjunction with other imaging modalities. A review of the literature has been undertaken and an imaging strategy suggested. It is concluded that bone scintigraphy has an important role to play as an imaging modality when investigating cases of chronic knee pain.

A comparative study of labelled neutrophil behaviour in patients with rheumatoid arthritis and normal volunteers.

A comparative study of neutrophil pharmacokinetics and distribution between normal volunteers and patients with rheumatoid arthritis (RA) is presented. White cell viability was confirmed by prominent localization of activity in the spleen with minimal liver uptake and lack of retention in the lungs in both normal volunteers and RA patients. There were no significant differences between both groups in granulocyte clearance from the lungs and their subsequent distribution in the spleen, bone marrow and liver. The results of this study demonstrate that the behaviour of granulocytes in RA patients is essentially unchanged from that of normal volunteers.

Radioleucoscintigraphy in osteoarthritis. Is there an inflammatory component?

The possible contribution of an inflammatory component in osteoarthritis was investigated. There was no correlation between the percentage uptakes of 99Tcm-hexamethylpropyleneamine oxime (HMPAO)-labelled white blood cells and 99Tcm-methylene diphosphonate (MDP) and between the former and pain scores. A significant correlation was found between the percentage uptake of 99Tcm-MDP and pain scores (0.002 > P > 0.01). In osteoarthritis, 99Tcm-HMPAO-labelled white cell imaging may or may not show a positive localization in the synovial membrane. Positive white cell localization appears to be limited to the area that corresponds to the radiological evidence of the condition and the positive uptake of the skeletal imaging agent.

The response of 99Tcm-methylene diphosphonate and 99Tcm-hexametazime-labelled neutrophils to intra-articular steroid injection in rheumatoid arthritis.

The synovial and bone uptake of tracer in the knees of patients with rheumatoid arthritis (RA) was quantified using 99Tcm-hexamethyl propylene amine oxime-labelled leucocytes and 99Tcm-methylene diphosphonate (MDP), respectively. Significant neutrophil migration and MDP uptake occurred in the knees of patients with RA irrespective of the disease duration. In all but one patient neutrophil migration was reduced after intra-articular steroid injection. The change in MDP uptake after steroid injection was variable. There was a significant correlation between the percentage reduction in neutrophil migration and pain score, while the latter correlated poorly with the change in MDP uptake. The quantification of the neutrophil component of the inflammatory process is a sensitive index for monitoring RA activity and response to pharmacological interventions, while quantitative bone scintigraphy should not be employed to monitor changes in joint inflammation in patients with RA.

Radiolabelled white blood cell imaging in arthritis. Is it a blood pool effect?

The aim of this study is to determine whether white blood cell imaging in inflammatory conditions is due to a blood pool effect as a result of an increased vascularity and vascular permeability, or whether cellular migration is the major contributing factor. It will be shown that white cell uptake is a specific phenomenon in the rheumatoid knee joint and not just a blood pool effect.

In vivo leukocyte migration in arthritis.

We quantitated in vivo migration of neutrophils into the knees of patients with rheumatoid arthritis (RA) and osteoarthritis, using 99mtechnetium-hexamethyl-propylene-amineoxime-labeled leukocytes and gamma scintigraphy. Significant neutrophil migration occurred in patients with RA irrespective of disease duration, and it was reduced by 60% following intraarticular steroid injection. The reduction in neutrophil migration correlated with reduction in pain. Leukocyte migration into osteoarthritic joints was also demonstrated, although it was much less than that seen in rheumatoid joints. No significant leukocyte migration into the joints of patients without arthritis was demonstrated. This technique appears to provide a sensitive method for quantitatively assessing the neutrophil component of inflammation in individual joints of patients with arthritis.

The effect of ramipril, a new angiotensin-converting enzyme inhibitor on cortical nephron flow and effective renal plasma flow in patients with essential hypertension.

A placebo-controlled study of Ramipril on total and intrarenal flow distribution was carried out in 7 patients with essential hypertension. Cortical nephron flow was measured using radiolabelled tubular secreted radiopharmaceuticals 123I orthoidohippurate or 99mTc mercaptoacetyl triglycine by the transit time distribution technique. Both systolic and diastolic blood pressure were reduced significantly by Ramipril without significant changes in an index of cardiac output or in effective renal plasma flow. Cortical nephron flow increased from 207 +/- 7 to 257 +/- 21 ml/min (mean +/- SEM) p less than 0.05 and the percentage of flow to cortical nephrons increased by 6% (p = 0.05). Ramipril corrects the reduced cortical nephron flow found in essential hypertension.

99Tcm-labelled leucocyte imaging in active rheumatoid arthritis.

A simplified technique of labelling leucocytes with technetium-99m is described and applied to patients with active rheumatoid arthritis. The clinically active and less active knees in seven patients were imaged and the uptake of labelled leucocytes was measured. The measurements were repeated after local steroid injection into nine painful knees. A 50-80% reduction in leucocyte uptake localized to the region of the synovium was demonstrated in the eight knees which showed clinical responses and a rise of 8% in the non-responder. There was a variable response in the knees that were not injected. 99Tcm leucocyte imaging in rheumatoid arthritis is able to assess objectively joint inflammation and its response to treatment.

Investigation of the parameters related to the formation of 99mTc-pyrophosphate complexes using gel chromatography column scanning.

Using gel chromatography two different 99mTc-PPi complexes (complex I and II) were observed under various pH-values. In neutral medium complex II was the main product while in acidic or alkaline media complexes I and II were formed. Our results related to the organ distribution in mice revealed that complex II is a bone-seeking agent whereas complex I concentrates in the kidneys.

Preparation, quality control and application of 99mTc-gluco-ene-diolate for renal scanning.

A one-step freeze-dried Sn-glucose kit was developed to be labelled with technetium-99m. TLC, paper chromatography and gel chromatography column scanning techniques (GCS) were used for the determination of the labelling yield of the complex. High radiochemical purity was obtained (98%). In vivo distribution studies were performed in white rats. Maximum uptake in kidneys (28%) was achieved in 15-90 min. The blood disappearance curve studies of the labelled Sn(II)-gluco-ene-diolate in rabbits have shown two disappearance phases of activity from blood with biological half-times of 10 and 150 min for the fast and slow component respectively.

Preparation, analysis and application of [99mTc]Human Albumin Microspheres ([99mTc]HAM) for lung scanning.

Kits were developed for the sterile labelling of Human Albumin Microspheres with 99mTc. The microspheres were prepared, sieved to get the desired particle size and autoclaved for sterilization. The spheres were treated with stannous chloride and the pH of the suspension was adjusted to 3.7 with phosphate buffer. After freeze-drying the contents of single reaction vials from different batches were reacted with 99mTc and the radiochemical yield (higher than 97%) was determined. The HAM kits were stable and the stability of [99mTc]HAM was followed for 5 h. Lung and liver uptake in mice was determined to be about 90 and 1% respectively. The preparation of [99mTc]HAM is performed in a single step process and excellent human lung scans were obtained.

A new technique for the preparation of ready-to-use macroaggregated albumin (MAA) kits to be labelled with 99mTc for lung scanning.

Kits were developed for the sterile labelling of macroaggregated albumin (human) with 99mTc. 0.4 mL of 20% HSA, 1 mL of SnCl2 X 2H2O containing 5 mg and 1.1 mL of 0.9% NaCl were sonified for 10 min. The pH was adjusted with phosphate buffer to 5.5 after the addition of 1 mL of 5% Tween-80. The solution was heated with stirring for 10 min at 80 degrees C for aggregation and 1.0 mL portions were placed in 10 mL vials for lyophilization. The contents of single reaction vials were reacted with 99mTc and the radiochemical yield determined (higher than 98%). The MAA kits were stable and the stability of [99mTc]-MAA was followed for 4.5 h. Lung uptake in mice was determined to be about 98.5%. The preparation of [99mTc]-MAA was performed in a single step process and excellent human lung scans were obtained.