1.Dual time point imaging of FDG PET/CT in a tuberculous spondylodiscitis
HR Abdul Razak ; N Abdul Rahim ; AJ Nordin
Biomedical Imaging and Intervention Journal 2010;6(2):1-3
Dual Time Point Imaging (DTPI) technique is a specialised protocol adopted in 18F-Fluorodeoxyglucose (FDG)
Positron Emission Tomography (PET) imaging. This technique is claimed to be useful in differentiating malignant and
infective lesions. The authors adopted this technique in a patient diagnosed with tuberculous spondylodiscitis and psoas abscess which demonstrated higher Maximum Standardized Uptake Value (SUVmax) during initial scans as compared with those obtained on delayed scans. The SUVmax changes between the two time points are believed to be a valuable finding for chronic granulomatous infective lesions such as tuberculosis.
2.Magnetic resonance-guided focused ultrasound surgery (MRgFUS) treatment for uterine fibroids
BJJ Abdullah ; RV Subramaniam ; SS Omar ; P Wragg ; N Ramli ; AL Wui ; CC Lee ; Y Yusof
Biomedical Imaging and Intervention Journal 2010;6(2):1-13
Magnetic Resonance-guided focused Ultrasound Surgery (MRgFUS) is gaining popularity as an alternative to
medical and surgical interventions in the management of symptomatic uterine fibroids. Studies have shown that it is an effective non-invasive treatment with minimal associated risks as compared to myomectomy and hysterectomy. MRgFUS can be offered to a majority of patients suffering from symptomatic uterine fibroids. It has been suggested that the use of broader inclusion criteria as well as the mitigation techniques makes it possible to offer MRgFUS to a much larger subset of patients than previously believed. This paper will describe how MRgFUS treatment for uterine fibroids
is performed at the University of Malaya Medical Centre, Kuala Lumpur, Malaysia.
3.Musculoskeletal MRI protocol
SP Tan ; A Suraya ; S Sa’don ; A Ruzi ; M Zahiah
Biomedical Imaging and Intervention Journal 2010;6(2):1-2
The authors propose a musculoskeletal (MSK) magnetic resonance imaging (MRI) protocol using selected
sequences for common orthopaedic indications. Selected sequences allow optimal visualisation of the indicated
pathology while screening for other common conditions. The authors emphasise the need for standard positioning of the
patient and standard orientation of scan planes to facilitate comparison with follow-up scans.
4.Overuse, Overdose, Overdiagnosis… Overreaction?
Biomedical Imaging and Intervention Journal 2010;6(3):1-3
When x-rays were first discovered, the harmful effects of radiation had to be manifest in the early users before they
were known. Today, radiation protection and safety have been established and the effects of radiation, as well as its risks, are known. Even so, medical radiation, in particular the growth in the use of computed tomography (CT), has resulted in soaring radiation doses received by the population in general. Inappropriate use has resulted in overuse, overdose and, perhaps, overdiagnosis, especially when used in screening. In the quest to control and curb the use of procedures involving radiation, however, we must be careful not to provoke a pandemic of irrational fear of radiation. Overreaction
to the overuse and overdose of radiation might deter patients from life-saving procedures.
5.Awareness and attitudes amongst basic surgical trainees regarding radiation in orthopaedic trauma surgery
FR Khan ; Z Ul-Abadin ; S Rauf ; A Javed
Biomedical Imaging and Intervention Journal 2010;6(3):1-4
This study investigated the awareness and attitudes of basic surgical trainees. Trainees were asked to answer
questions from a pre-set questionnaire. Fifty basic surgical trainees from England and Wales were involved in the study. The areas covered were basic knowledge of radiation hazards, use of protective wear, pregnancy test in female trauma victims of reproductive age, and principles of safe radiation. All the questions were asked in the context of orthopaedic trauma surgery. All questions were evidence based. It was unfortunate to notice that basic surgical trainees are lacking in the essential knowledge of ionising radiation.
Most of the trainees are not adhering to radiation safety principle, and are not practising safely. The authors strongly recommend that surgical trainees should have more robust training and information available in this context. And they suggest that it should be provided on local, regional and national basis.
6.Uterine artery embolisation for symptomatic fibroids: the University of Malaya Medical Centre experience
RN Subramaniam ; A Vijayananthan ; SZ Omar ; O Nawawi ; BJJ Abdullah
Biomedical Imaging and Intervention Journal 2010;6(3):1-6
Background: Transcatheter uterine artery embolisation (UAE) for the treatment of symptomatic fibroids has been
performed in several centres in the United States, Western Europe and Asia with promising results. This study reports
the authors' experience with UAE at the University Malaya Medical Centre. Method: Fifty women with symptomatic
uterine fibroids who declined surgery were treated by transcatheter UAE. The uterine arteries were selectively
catheterised and embolised with polyvinyl alcohol particles. Post-procedure analgesia was administered via patientcontrolled analgesic pump. The patients were followed up at an interval of 6/12 clinically and with MRI. Results: Transcatheter UAE was performed on all 50 patients with no major complications. 49 patients had both uterine arteries embolised while 1 patient had only the right uterine artery embolised on account of hypoplasia of the left uterine artery due to previous myomectomy. The mean hospital stay was 3.5 days (range, 2 to 7). At a mean follow-up of 24/52, all patients reported improvements in their presenting symptoms. Objective improvement in terms of reduction of uterine and fibroid sizes was determined on MRI. One patient, who initially responded with a decrease in uterine and dominant fibroid size, became symptomatic (menorrhagia) after 6 months and subsequent endometrial sampling revealed cystic
glandular hyperplasia for which total abdominal hysterectomy was performed. Two other patients had no change in symptoms and after hysterectomy, the pathology revealed concurrent adenomyosis. Another 2 patients with cervical fibroids were treated with hysterectomy as there was no gross reduction in the size of fibroid following UAE. Overall, 90% of the patients had dramatic improvement of anaemia and symptoms at 1 year follow-up. Conclusion: Out of the 50 patients, 17 patients had total disappearance of their fibroids and 28 patients had more than 50% reduction in the size of fibroids after 1 year. 5 patients ended up with total abdominal hysterectomy. These results suggest that UAE is an appealing alternative to hysterectomy or myomectomy for many women with symptomatic fibroids.
7.Evaluation of dose coverage to target volume and normal tissue sparing in the adjuvant radiotherapy of gastric cancers: 3D-CRT compared with dynamic IMRT
KK Murthy ; KA Shukeili ; SS Kumar ; CA Davis ; RR Chandran ; S Namrata
Biomedical Imaging and Intervention Journal 2010;6(3):1-7
Purpose: To assess the potential advantage of intensity-modulated radiotherapy (IMRT) over 3D-conformal
radiotherapy (3D-CRT) planning in postoperative adjuvant radiotherapy for patients with gastric carcinoma. Methods
and materials: In a retrospective study, for plan comparison, dose distribution was recalculated in 15 patients treated with 3D-CRT on the contoured structures of same CT images using an IMRT technique. 3D-conformal plans with three fields and four-fields were compared with seven-field dynamic IMRT plans. The different plans were compared by analyzing the dose coverage of planning target volume using TV95, Dmean, uniformity index, conformity index and homogeneity index parameters. To assess critical organ sparing, Dmean, Dmax, dose to one-third and two-third volumes of the OARs and percentage of volumes receiving more than their tolerance doses were compared. Results: The average dose coverage values of PTV with 3F-CRT and 4F-CRT plans were comparable, where as IMRT plans achieved better target coverage(p<0.001) with higher conformity index value of 0.81±0.07 compared to both the 3D-CRT plans. The doses to the liver and bowel reduced significantly (p<0.001) with IMRT plans compared to other 3D-CRT plans. For all OARs the percentage of volumes receiving more than their tolerance doses were reduced with the IMRT plans.
Conclusion: This study showed that a better target coverage and significant dose reduction to OARs could be achieved with the IMRT plans. The IMRT can be preferred with caution for organ motion. The authors are currently studying organ motion in the upper abdomen to use IMRT for patient treatment.
8.Optimal slice thickness for cone-beam CT with on-board imager
Seet KYT ; Barghi A ; Yartsev S ; Van Dyk J
Biomedical Imaging and Intervention Journal 2010;6(3):1-4
Purpose: To find the optimal slice thickness (Δτ) setting for patient registration with kilovoltage cone-beam CT (kVCBCT) on the Varian On Board Imager (OBI) system by investigating the relationship of slice thickness to automatic registration accuracy and contrast-to-noise ratio.
Materials and method: Automatic registration was performed on kVCBCT studies of the head and pelvis of a RANDO anthropomorphic phantom. Images were reconstructed with 1.0 ≤ Δτ (mm) ≤ 5.0 at 1.0 mm increments. The phantoms were offset by a known amount, and the suggested shifts were compared to the known shifts by calculating the residual error. A uniform cylindrical phantom with cylindrical inserts of various known CT numbers was scanned with kVCBCT at 1.0 ≤ Δτ (mm) ≤ 5.0 at increments of 0.5 mm. The contrast-to-noise ratios for the inserts were measured at each Δτ.
Results: For the planning CT slice thickness used in this study, there was no significant difference in residual error below a threshold equal to the planning CT slice thickness. For Δτ > 3.0 mm, residual error increased for both the head and pelvis phantom studies. The contrast-to-noise ratio is proportional to slice thickness until Δτ = 2.5 mm. Beyond this point, the contrast-to-noise ratio was not affected by Δτ.
Conclusion: Automatic registration accuracy is greatest when 1.0 ≤ Δτ (mm) ≤ 3.0 is used. Contrast-to-noise ratio is optimal for the 2.5 ≤ Δτ (mm) ≤ 5.0 range. Therefore 2.5 ≤ Δτ (mm) ≤ 3.0 is recommended for kVCBCT patient registration where the planning CT is 3.0 mm
9.Chest imaging features of patients afflicted with Influenza A (H1N1) in a Malaysian tertiary referral centre
Bux SI ; Mohd. Ramli N ; Ahmad Sarji S ; Kamarulzaman A
Biomedical Imaging and Intervention Journal 2010;6(4):1-4
This is a retrospective descriptive study of the chest imaging findings of 118 patients with confirmed A(H1N1) in a tertiary referral centre. About 42% of the patients had positive initial chest radiographic (CXR) findings. The common findings were bi-basal air-space opacities and perihilar reticular and alveolar infiltrates. In select cases, high-resolution computed tomography (CT) imaging showed ground-glass change with some widespread reticular changes and atelectasis.
10.Significance of subcentimetre 18F-FDG PET/CT pulmonary abnormality in patients with known extrapulmonary malignancy
Biomedical Imaging and Intervention Journal 2010;6(4):1-4
The significance of a subcentimetre 18F-FDG PET/CT pulmonary abnormality in a patient with known
extrapulmonary primary malignancy can have a major impact on the clinical management of the patient. The clinician’s
reliance on the semi-quantitative and qualitative PET/CT analysis of the abnormality has, at times, led to untoward
diagnostic problems, given the limited spatial resolution of PET for a small volume lesion performed as part of the
standard PET/CT study. This paper highlights a case each of an FDG-positive and an FDG-negative focal pulmonary
abnormality in a combined PET/CT study of patients with known extrapulmonary malignancy.