Urografi intravena (IVU) dan tomografi berkomputer helikal tanpa kontras (UHCT) urografi adalah dua prosedur utama yang akan dijalankan semasa penyiasatan radiologi bagi pengesanan urolitiasis (batu karang) pada sistem genitourinari. Dedahan terhadap sinaran radiasi merupakan faktor kebimbangan utama dalam kedua-dua prosedur. Oleh itu, satu kajian perbandingan dos sinaran telah dijalankan antara prosedur IVU dan UHCT urografi di samping menentukan faktor dedahan optimum bagi kedua-dua prosedur tersebut. Kajian ini telah dijalankan ke atas fantom antropomorfik seluruh tubuh mengikut protokol sebenar bagi prosedur UHCT urografi dan penghasilan radiografi bersiri berserta dengan pemberian media berkontras bagi prosedur IVU. Sebanyak tiga parameter dedahan voltan tiub digunakan iaitu 75 kVp, 80 kVp dan 85 kVp bagi prosedur IVU dan 100 kVp, 120 kVp dan 140 kVp bagi prosedur UHCT urografi . Hasil dos sinaran bagi prosedur IVU yang diperolehi adalah 1.40 mSv, 2.10 mSv dan 2.79 mSv bagi 75 kVp, 80 kVp dan 85 kVp. Manakala bagi prosedur UHCT urografi , sebanyak 0.76 mSv, 1.32 mSv dan 1.82 mSv dos sinaran direkodkan bagi 100 kVp, 120 kVp dan 140 kVp. Hasil kualiti imej optimum adalah menggunakan dedahan sebanyak 85 kVp bagi prosedur IVU dan 120 kVp bagi prosedur UHCT urografi . Kesimpulannya, walaupun tidak terdapat perbezaan signifi kan, dos sinaran yang terhasil daripada prosedur IVU adalah kekal lebih tinggi daripada prosedur UHCT urografi .
The aims of this study are (1) to determine the scattered radiation dose levels in routine fluoroscopy procedures and (2) to compare them with the equivalent chest x-rays and also (3) to monitor common techniques and radiation safety measures taken by the medical officers. The study covered a sample of 105 fluoroscopic procedures performed by 18
medical officers. Each officer wore a personal pocket dosimeter inside the lead gown during each procedure. A digital dosimeter was placed near the detector of the fluoroscopy unit while a survey meter was positioned at the control panel area to record the dose levels. There were 14 types of examination included in this study. The total number of images
captured was found to be the highest in barium swallow examination with 115 images, almost five times higher compared to the common practices. The longest screening time was observed in barium enema examination which is 9.15 seconds. The median of the scattered dose level was the highest in barium meal examination (165.50 µSv) which is equivalent
to 8.28 times of average dose impart by chest x-ray examinations. The number of images and the length of screening time depend on the competency levels of the medical officers. They capture as many images as possible to avoid missing any abnormalities, therefore it will always be better if the fluoroscopist is consulted during each case. They should also
consistently practice essential protection by minimizing exposure time, maximizing distance from the source tube and utilizing the radiation shielding.
Urografi intravena (IVU) dan tomografi berkomputer helikal tanpa kontras (UHCT) urografi adalah dua prosedur utama
yang akan dijalankan semasa kajian radiologi bagi pengesanan urolitiasis (batu karang) pada sistem genitourinari.
Dedahan terhadap sinaran radiasi merupakan faktor kebimbangan utama dalam kedua-dua prosedur. Oleh itu, satu
kajian perbandingan dos sinaran telah dijalankan antara prosedur IVU dan UHCT urografi di samping menentukan faktor
dedahan optimum bagi kedua-dua prosedur tersebut. Kajian ini telah dijalankan ke atas fantom antropomorfi seluruh
tubuh mengikut protokol sebenar bagi prosedur UHCT urografi dan penghasilan radiografi bersiri beserta dengan
pemberian media berkontras bagi prosedur IVU. Sebanyak tiga parameter dedahan voltan tiub digunakan iaitu 75, 80
dan 85 kVp bagi prosedur IVU dan 100, 120 dan 140 kVp bagi prosedur UHCT urografi. Hasil dos sinaran bagi prosedur
IVU yang diperoleh adalah 1.40, 2.10 dan 2.79 mSv bagi 75, 80 dan 85 kVp. Manakala bagi prosedur UHCT urografi,
sebanyak 0.76, 1.32 dan 1.82 mSv dos sinaran direkodkan bagi 100, 120 dan 140 kVp. Hasil kualiti imej optimum adalah
menggunakan dedahan sebanyak 85 kVp bagi prosedur IVU dan 120 kVp bagi prosedur UHCT urografi. Kesimpulannya,
walaupun tidak terdapat perbezaan signifikan, dos sinaran yang terhasil daripada prosedur IVU adalah tekal lebih tinggi
daripada prosedur UHCT urografi.
The purpose of this study was to evaluate the image quality and diagnostic accuracy of coronary computed tomography angiography (CCTA) using 640-slice scanner. Advancement of multidetector computed tomography (MDCT) technology with higher spatial, temporal resolution, and increasing detector array have improved the image quality and diagnostic accuracy of CCTA. A total of 25 patients (12 men and 13 women) underwent CCTA examination was chosen and data was acquired by 640-slice scanner. All 16 segments of coronary arteries were evaluated by two reviewers using a 4-likert scale for qualitative assessment. In quantitative assessment, the evaluation of 4 main coronary arteries were analysed in terms of signal intensity (SI), image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR). All 25 patients with a mean age of 52.88 ± 14.75 years old and body mass index (BMI) of 24.24 ± 3.28 kg/m2 were analysed. In qualitative assessment, from the total of 400 segments, 379 segments (95%) had diagnostic value while 21 segments did not have diagnostic value, which means 5% artefact was detected. In quantitative assessment, there was no statistical differences in gender, race, and BMI (p>0.05). Overall evaluation showed that higher SI at the left main artery (LM) at 393.7 ± 47.19. Image noise was higher at right coronary artery (RCA) at 39.01 ± 13.97. SNR and CNR showed higher at left anterior descending (LAD) with 12.73 ± 5.17 and LM 9.14 ± 4.2, respectively. In conclusion, this study indicates that 640-slice MDCT has higher diagnostic value in CCTA examination with 95% vessel visibility with 5% artefact detection.
This study was carried out to compare the effective dose, size specific dose estimation (SSDE) and scan length between genders and between CT scanner with different slice number. A total of 245 set data of radiation dose and scan length for CT scanning procedure involving thorax, abdomen and pelvis regions were obtained retrospectively for comparisons. 111 patients (60 males and 51 females) were scanned using 160-slices CT scanner while 134 patients (71 males and 63 females) were scanned using 640-slices CT scanner. Generally, there were no significant differences in the radiation dose and scan length among genders. However, differences for SSDE in CT thorax and CT thorax-abdomen-pelvis (TAP) protocols exist whereby in CT thorax protocol, 640-slices CT scanner had a significantly higher value of SSDE (9.06±2.67 mGy) than that in 160-slices CT scanner (7.82±1.33 mGy). Similarly to the CT TAP protocol, whereby 640-slices CT scanner had a significantly lower value in SSDE (9.17±1.59 mGy) than that in 160-slices CT scanner (10.76±3.72 mGy). In conclusion, there was no significant difference in the radiation dose and scan length between genders but significant difference was only observed in SSDE due to the presence of body size variation among the study population especially in different CT scanners.
Acute urinary retention (AUR) is one of the most serious complications of benign prostatic hypertrophy. This study was done to predict the outcome of trial of voiding without catheter (TWOC) in patients with AUR with intravesical prostatic protrusion (IPP) detected on transabdominal ultrasound. Other factors such as prostatic volume and patient's age were also assessed.