[en] Short communication

[en] Short communication

[en] Short communication

[en] Short communication

[en] Full text: Nitrates have long been the standard therapy for chronic stable angina. The goals of this study were to define the reduction in exercise induced ischaemia among patients treated with isosorbide mononitrate and to examine the issue of tolerance, using quantitative stress myocardial perfusion SPECT (M-SPECT) defect extent and severity as end-point. A total of 20 male patients (mean age: 71.3 years) were studied. Inclusion criteria were chronic stable angina, previously abnormal M-SPECT with demonstrable reversible defect in at least one vascular territory, and no recent Ml or revascularisation. Following baseline M-SPECT off antianginal medication, isosorbide mononitrate was commenced at 6O mg/day for four days, and then at 120 mg/day from the fifth day The second SPECT was performed on Day 5 and the third SPECT after 30-42 days (mean: 35 days) of continuous treatment. Each M-SPECT was processed using a previously validated, commercially available quantitative analysis software package (CEqual) for stress defect reversibility extent (=ischaemic size) and defect severity (=degree of ischaemia) for total left ventricular myocardium and for each coronary vascular territory. The exercise duration and workload were equivalent between all three M-SPECT studies. Total LV ischaemic extent with exercise was reduced (p<0.002) by 9% from baseline to day 5 and by 135 between baseline and day 35 SPECT studies. Ischaemic severity index was also reduced (p<0.0003) by 15% between baseline and day 5 and 14 % between baseline and day 35. Sustained reduction for both ischaemic extent and severity was similarly observed for individual vascular territories with no development of trachyphylaxis over the prescribed treatment period

[en] Full text: A 83 year old female presented to our department for an Indium-111 Octreotide study to evaluate her carcinoid syndrome with the view of delivering therapeutic doses of Indium-111 Octreotide. Indium-111 Octreotide uptake has been shown in tumours with high-affinity somatostatin receptor sites. In many instances a positive scintigram predicts a favourable response to treatment with Octreotide. The diagnostic scan appearance demonstrated abnormal increased focal uptake in multiple sites of both lobes of the liver and one in the right iliac fossa, her primary site. Before the therapeutic doses, both haematological and biochemical indices of her carcinoid were performed to evaluate therapeutic response. The patient was then admitted into our isolation room and underwent 3 therapeutic doses of Indium-111 Octreotide of between 180 and 350 mCi intravenously at 4 to 6 weekly intervals. A post-therapeutic total body scan with abdominal SPECT was performed after each dose to assess therapeutic uptake and response. Before the second therapeutic dose, an FDG coincidence PET study was performed. This scan corresponded with similar sites of uptake to the Octreotide scan The patient has now had 2 of her 3 therapeutic doses with the third due in late January 1998. At this point of time her biochemical indices and clinical facial flushing and diarrhoea have shown favourable response to therapy

[en] Full text: A 24 year old female had previously been treated with radiotherapy for a low-grade astrocytoma of the left frontal lobe. Despite medication, she had since suffered increasingly frequent partial seizures which dramatically reduced her quality of life. She was assessed for resection of the epileptic focus. Inter-ictal and ictal single photon emission computed tomography (SPECT) were acquired following injections of ^99mTc HMPAO (CERETEC). Routine image interpretation did not allow confident localization of the seizure focus. However, when these images were superimposed and subtracted, an area of ictal hyperperfusion on the posterior margin of the tumour was identified. The resultant image was co-registered with magnetic resonance imaging (MRI). A subdural electrode grid was implanted over this area and adjacent frontal cortex. Subsequent ictal electroencephalogram (EEG) recordings confirmed that this area was the seizure focus. Local cortical stimulation through the grid indicated that it could be safely resected. Following left frontal lobectomy using margins defined by the subdural grid, the patient has been seizure free and suffered no neurological deficits. This case study is an example of the benefits to be gained by the co-registration of functional and anatomical imaging

[en] Full text: The recommended method for the preparation of 99mTc-MIBI and 99mTc-MAG3 requires that they be heated in a boiling water bath for 10 minutes, after reconstitution with sodium pertechnetate. This method is both inconvenient and time consuming. A more rapid and convenient method for the preparation of these radiopharmaceuticals employs a conventional microwave oven. However, a serious limitation of this method is the hazard associated with an explosion of a vessel containing a radioactive substance. Traditionally, mixtures that can potentially explode are contained in a device called a 'bomb'. We have developed a method, utilising such a device, that allows us to rapidly and safely prepare 99mTc-MIBI and 99mTc-MAG3 using a microwave oven. This device is used in our department on a daily basis. Since using the teflon bomb, there has been one incidence of an explosion, which was successfully contained within the bomb. There was no statistically significant difference between the radiochemical purity (RCP) of the microwave prepared samples and those obtained using the recommended method. In conclusion, 99mTc-MIBI and 99mTc-MAG3 can be safely prepared and quality controlled in under ten minutes using a microwave oven and our teflon bomb. The average RCP for 99mTc-MIBI and 99mTc-MAG3 prepared using a microwave oven were 97.0+2.0% (n=19) and 99.8+0.2 (n=7) respectively

[en] Full text: Gallium-67 Citrate (Ga-67) scans are well established in management protocols of patients with lymphoma. Thallium-201 Chloride (Tl-201)scans have a less well defined role, being used largely in patients with histologically low grade disease. We report the findings in 110 consecutive patients referred for combined Tl-201 and Ga-67 scans for the management of Hodgkin's Disease or non-Hodgkin's Lymphoma. Each patient underwent multiple static views and Single Photon Emission Computer Tomography (SPECT) with a dual-head gamma camera, 10 minutes after intravenous administration of 120MBq of Tl-201. Then, 370MBq of Ga-67 was administered intravenously, and the patients scanned at 48 and 72 hours with whole body sweeps, multiple static views and SPECT. The distribution and degree of abnormal increased uptake of Tl-201 were compared with that of Ga-67. Correlation with clinical disease status as determined by conventional means of nodal and extranodal sites, was also undertaken. The sensitivity and specificity of, and concordance between each radionuclide were determined for each histological type of lymphoma. In most cases, there was concordance between the Tl-201 and Ga-67 scans. Gallium-67 was however more sensitive overall. Thallium-201 was more convenient, with greater sensitivity in some types of lymphoma. This may allow a more selective approach based on individual clinical circumstances

[en] Full text: Acute or chronic knee pain is common amongst athletic persons. MRI is generally regarded as the best test, but is not widely available and may lack specificity in meniscal tears and cruciate injury. Bone scan with SPECT is an appealing alternative since it is relatively cheap and easily obtained. Further, a number of investigators have published data indicating sensitivity and specificity exceeding 85%. The purpose of the study is to determine typical scintigraphic findings in medial collateral ligament or medial meniscus injury. We present a small group of patients with acute knee trauma in whom arthroscopy and/or clinical follow-up indicated medial collateral ligament injury. Bone scans were undertaken after 900-1000 MBq of ^99mTc-MDP with immediate blood pool, delayed planar images and SPECT acquired on a Picker Prism 2000. SPECT was obtained with high resolution collimators and 20 sec/stop for 180 deg each. SPECT images showed focal radiopharmaceutical accumulation in the medial proximal tibial shaft and medial femoral condyle, corresponding to the superficial layer of the medial collateral ligament (best seen on coronal images). Disruption of the deep layer and/or medial meniscus can be suspected with abnormal uptake in part or all of the meniscus (best seen on transverse images). We conclude that acute/chronic medial collateral ligament injury can be detected on bone scintigraphy with abnormal uptake at the predicted anatomic site of attachment