Search tips
Search criteria

Results 1-6 (6)

Clipboard (0)
more »
Year of Publication
Document Types
1.  Displacement of the lumpectomy cavity defined by surgical clips and seroma based on 4D-CT scan for external-beam partial breast irradiation after breast-conserving surgery: a comparative study 
Ding, Y | Li, J | Wang, W | Wang, S | Fan, T | Xu, M | Shao, Q | Ma, Z
The British Journal of Radiology  2013;86(1030):20130416.
To compare the displacements of the lumpectomy cavity delineated by the surgical clips and the seroma based on four-dimensional CT (4D-CT) for external-beam partial breast irradiation (EB-PBI) after breast-conserving surgery (BCS).
14 breast cancer patients after BCS were recruited for EB-PBI and undertook 4D-CT simulation. On the 10 sets of the 4D-CT images, all the surgical clips in the cavity were delineated. The gross tumour volume (GTV) formed by the clips, the seroma, and both the clips and the seroma were defined as GTVc, GTVs and GTVc+s, respectively. The displacements of the centre of mass (COM) of the clips, GTVc, GTVs, GTVc+s and the selected clips in the three-dimensional (3D) directions were recorded and compared.
In the left–right, anterior–posterior and superior–inferior directions, the displacements were 2.20, 1.80 and 2.70 mm for the clip COM; 0.90, 1.05 and 1.20 mm for GTVc; 0.80, 1.05 and 0.80 mm for GTVs; and 0.90, 1.20 and 1.40 mm for GTVc+s, respectively. In the 3D directions, the displacements of the clip COM were greater than the GTVc, GTVs, GTVc+s, and the displacements of the clip COM, GTVc+s, GTVc and GTVs were significantly greater than the displacements of the selected clips (p<0.05).
The displacements of the clip COM were greater than that of the GTVc, GTVs, GTVc+s and the four selected clips. The optimal internal target volume should be defined based on the boundary displacements.
Advances in knowledge:
When the GTV was delineated using the clips and/or the seroma, there was displacement difference between the lumpectomy cavity centre and the boundary for the EB-PBI. The optimal internal target volume should be defined based on the boundary displacements of the lumpectomy cavity.
PMCID: PMC3798338  PMID: 23995875
2.  Patient-reported complications from fiducial marker implantation for prostate image-guided radiotherapy 
The British Journal of Radiology  2012;85(1015):1011-1017.
To report on complications from transrectal ultrasound-guided insertion of fiducial markers for prostate image-guided radiotherapy.
234 patients who underwent transrectal fiducial marker insertion for prostate cancer image-guided radiotherapy were assessed retrospectively by questionnaire with regard to the duration and severity of eight symptoms experienced following the procedure. Pain during the implantation procedure was assessed according to the Wong–Baker faces pain scale.
Of 234 patients, 32% had at least one new symptom after the procedure. The commonest new symptom following the procedure was urinary frequency affecting 16% of patients who had not been troubled by frequency beforehand. Haematuria, rectal bleeding, dysuria and haematospermia affected 9–13% of patients, mostly at Grade 1 or 2. Pain, obstruction, and fever and shivers affected 3–4% of patients. Grade 3 rectal bleeding, haematuria, fever and shivers, and urinary frequency affected 0.5–1.5% of patients. Only one patient had a Grade 4 complication (i.e. fever and shivers). Overall, 9% of patients had symptoms lasting more than 2 weeks. The commonest symptoms that lasted more than 2 weeks were frequency, dysuria, obstructive symptoms and rectal bleeding. Mean pain score during the procedure was 1.1 (range 0–5).
Transrectal ultrasound-guided fiducial marker insertion for image-guided radiotherapy is well tolerated in the majority of prostate cancer patients. Most symptoms were Grade 1 or 2 in severity. Symptoms in the majority of patients last under 2 weeks. The most serious complication was sepsis in our study.
PMCID: PMC3474069  PMID: 22253345
3.  A pilot study to evaluate assisted freehand ultrasound elasticity imaging in the sizing of early breast cancer: a comparison of B-mode and AFUSON elasticity ultrasound with histopathology measurements 
The British Journal of Radiology  2011;84(1007):1011-1019.
This pilot study investigates the role of assisted-freehand ultrasound (AFUSON) elasticity imaging of the breast in assessing the contour, size and area of 23 early breast cancers by making comparison of AFUSON with the equivalent B-mode ultrasound images and gold standard histopathology slides.
The B-mode, AFUSON and digitised histopathology slides of three early breast cancers were compared for contour, size and area with histopathology scans. AFUSON features that corresponded to areas of known malignant change on the histopathology slides were regarded as diagnostic. These diagnostic criteria were then applied to the B-mode and AFUSON elasticity images of all 23 breast cancers in the pilot study without having the availability of the histopathology scans for reference. Corresponding diameters were measured and the results were compared with the equivalent measurements on the scans of the histology slides. The results were tabulated in histogram form. Diagnostic confidence levels were evaluated.
Size dimension accuracy increased from 66% using B-mode alone to 82% using combined B-mode and AFUSON elasticity images. Tumour area accuracy was also increased. A small number of cases had a striking visual similarity of shape on AFUSON elasticity scans and histopathology slides.
In spite of the shortfalls in this study, AFUSON elasticity imaging was capable of acquiring some high-quality images that showed strong correlation between AFUSON elasticity and scans of histology slides. Further studies will be carried out to refine the technique and determine if it has a role in the diagnosis and management of breast cancer.
PMCID: PMC3473697  PMID: 21632651
4.  Directional diffusivity changes in the optic nerve and optic radiation in optic neuritis 
Li, M | Li, J | He, H | Wang, Z | Lv, B | Li, W | Hailla, N | Yan, F | Xian, J | Ai, L
The British Journal of Radiology  2011;84(1000):304-314.
Optic neuritis (ON) is defined as an inflammation of the optic nerve and provides a useful model for studying the effects of inflammatory demyelination of white matter. The aim of this study was to assess the diffusion changes in both the optic nerve and optic radiation in patients with acute and chronic ON using diffusion tensor (DT) MRI.
33 patients with idiopathic demyelinating optic neuritis (IDON) and 33 gender- and age-matched healthy controls were examined with DT-MRI and with T1 and T2 weighted MRI.
Compared with controls, both first-episode and recurrent patients with IDON in the acute stage showed significantly increased radial diffusivity (λ⊥) and decreased mean fractional anisotropy (FA) in the affected nerves. Reduced FA, increased λ⊥, mean diffusivity (MD) and axial diffusivity (λ∥) were determined in patients with subacute IDON. We found no significant difference in the directional diffusivity of optic radiation in patients whose disease had lasted less than 1 year compared with healthy controls. However, significant changes in the FA and λ⊥ of the optic radiation were detected in patients with disease duration of more than 1 year.
These results show the great potential and capacity of DT-MRI measures as useful biomarkers and indicators for the evaluation of myelin injury in the visual pathway.
PMCID: PMC3473480  PMID: 21415301
5.  Radiation dose and cancer risk in retrospectively and prospectively ECG-gated coronary angiography using 64-slice multidetector CT 
The British Journal of Radiology  2010;83(986):152-158.
This study aimed to estimate the radiation dose and cancer risk to adults in England, the USA and Hong Kong associated with retrospectively and prospectively electrocardiogram (ECG)-gated coronary computed tomography angiography (CTA) using currently practised protocols in Hong Kong. The doses were simulated using the ImPACT spreadsheet. For retrospectively ECG-gated CTA with pitches of 0.2, 0.22 and 0.24, the effective doses were 27.7, 23.6 and 20.7 mSv, respectively, for males and 23.6, 20.0 and 18.8 mSv, respectively, for females. For prospectively ECG-gated CTA, the effective dose was 3.7 mSv for both males and females. A table of lifetime attributable risks (LAR) of cancer incidence was set up for the English population for the purpose of estimating cancer risk induced by low-dose radiation exposure, as previously reported for US and Hong Kong populations. From the tables, the LAR of cancer incidence for a representative 50-year-old subject was calculated for retrospectively ECG-gated CTA to be 0.112% and 0.227% for English males and females, respectively, 0.103% and 0.228% for US males and females, respectively, and was comparatively higher at 0.137% and 0.370% for Hong Kong males and females, respectively; for prospectively ECG-gated CTA, the corresponding values were calculated to be 0.014% and 0.035% for English males and females, respectively, and 0.013% and 0.036% for US males and females, respectively, and again were higher at 0.017% and 0.060% for Hong Kong males and females, respectively. Our study shows that prospectively ECG-gated CTA reduces radiation dose and cancer risks by up to 87% compared with retrospectively ECG-gated CTA.
PMCID: PMC3473541  PMID: 20139263
6.  Dose estimation by chromosome aberration analysis and micronucleus assays in victims accidentally exposed to 60Co radiation 
The British Journal of Radiology  2009;82(984):1027-1032.
The objective of this study was to assess the radiation exposure levels in victims of a 60Co radiation accident using chromosome aberration analysis and the micronucleus assay. Peripheral blood samples were collected from three victims exposed to 60Co 10 days after the accident and were used for the chromosome aberration and micronucleus assays. After in vitro culture of the lymphocytes, the frequencies of dicentric chromosomes and rings (dic+r) and the numbers of cytokinesis blocking micronuclei (CBMN) in the first mitotic division were determined and used to estimate radiation dosimetry. The Poisson distribution of the frequency of dic+r in lymphocytes was used to assess the uniformity of the exposure to 60Co radiation. Based on the frequency of dic+r in lymphocytes, estimates of radiation exposure of the three victims were 5.61 Gy (A), 2.48 Gy (B) and 2.68 Gy (C). The values were estimated based on the frequencies of CBMN, which were 5.45 Gy (A), 2.78 Gy (B) and 2.84 Gy (C). The estimated radiation dosimetry demonstrated a critical role in estimating the radiation dose and facilitating an accurate clinical diagnosis. Furthermore, the frequencies of dir+r in victims A and B deviated significantly from a normal Poisson distribution. Chromosome aberration analysis offers a reliable means for estimating biological exposure to radiation. In the present study, the micronucleus assay demonstrated a high correlation with the chromosome aberration analysis in determining the radiation dosimetry 10 days after radiation exposure.
PMCID: PMC3473381  PMID: 19366736

Results 1-6 (6)