showing extension to neighboring structures. The findings of the vascular lesions on TRICKS-MRA are shown in table 3. TRICKS-MRA was an accurate method in assessment of the size of AVM nidus. Eleven out of fifteen (73.3%) lesions were found to be larger than 2cm on TRICKS compared to 8/15 on MRI+C (53.3%) as well as in detection of the feeding arteries, whether single 9/15 (60%) (Fig 1 & 5) or multiple 6/15 (40%) (Fig. 2), and draining veins; superficial 8/15 (53.3%) or deep 7/15 (46.7%). Regarding the 5 patients with hemangiomas (see Fig 3& 4), 4 patients (80%) of them showed single arterial feeder, while one patient (20%) with peri-orbital hemangioma had dual arterial feeding. The two patients with low flow venous malformation …show more content…
Proper assessment is necessary to confirm the diagnosis and precisely determine structure of lesions, their size and topographic relationships before planning most effective treatment [21]. Color Doppler ultrasound imaging used for initial assessment of small superficial lesions and in follow-up in order to assess their evolution, but of limited role in proper assessment of adjacent soft tissue and osseous structure and depend on diagnostician’s experience [22]. Multislice CT has improved temporal resolution and spatial resolution in the scanning direction for CT angiography [23]. However, CTA examinations are high-radiation dose studies and it is not always possible to clearly differentiate between the lesion and adjacent tissues [24, 25]. DSA is the standard examination in assessment of AVMs, but it is an invasive procedure with risk of vascular injury and exposure to ionizing radiation. Additionally, DSA will characterize only the patent component of the vascular lesion which can lead to an underestimation of lesion size [26-28]. MRI with its high spatial resolution and multiplanar imaging can precisely assess vascular lesions and their relationships with nearby structures such as skin, subcutaneous tissue, muscles, nerves and bones. T2-weighted sequences with fat saturation and T1-weighted sequences after contrast administration enable determining the
et al who found a very high positive correlation between the type of curve and pathological staging (r= 0.88 , p<0.001) (21) .
AEC maxed out: GE’s automatic exposure control (AEC) tools, SmartmA and AutomA, select tube current levels during an exam between minimum and maximum tube current limits based upon the patient habitus as interpreted from the last acquired CT localizer radiograph. If the noise index requested for an image is lower than is allowed by the maximum tube current, the AEC will choose the maximum tube current throughout the scan. This infrequent occurrence can happen due to patient positioning which increases patient dose [17, 18, 31, 32], improperly chosen or set-up protocol [21, 33], or large patient size. If a scan is maxed out in mA for the entire scan, then the average and the maximum mA values will be identical. In such a case, we classify the protocol as having either a manual mA technique or being “maxed out”. If the maximum mA and the average are not equal, then we classify the irradiation event as having utilized
All MR images were evaluated in T2WI and DWI for site, size, and signal intensity of the
The pseudocapsules around some FNH lesions result from compressed liver parenchyma and vessels surrounding the lesion and an inflammatory reaction. The pseudocapsule of FNH is often seen with high signal intensity on T2-weighted images and enhances on delayed contrast-enhanced sequences. In contrast to this pseudocapsule, the true capsule of hepatocellular carcinoma shows low signal intensity on both T1- and T2-weighted images, with persistent enhancement on delayed contrast-enhanced sequences (37).
Ranschaert, E. (n.d.). Superior mesenteric artery syndrome | Radiology Reference Article. Retrieved February 18, 2017, from https://radiopaedia.org/articles/superior-mesenteric-artery-syndrome.
A physician can diagnose Blue Rubber Syndrome by doing a clinical examination of a patient who has skin lesions, GI bleeding, or a family history of multiple venous malformations. The GI tract is then viewed through endoscopy (passage of a scope into the stomach and lower intestine). Magnetic Resonance Imaging (MRI) and ultrasound is essential in evaluating massive malformations or deep lesions and their relationship to structures under the skin. MRI is the most sufficient method to determine the extent of deep lesions. MRI can also assess to what degree the underlying bones and joints are involved. The low circulation nature of the lesions is best determined by Doppler interrogation (Kassarjian, et al., 2003).
soft tissue. The importance of early diagnosis is vital to the management and surgical removal of
Echocardiographic examination revealed diastolic relaxation delay with an ejection fraction of 67%. Cerebral MR angiography demonstrated 85-90% stenosis at the proximal part of the basilar artery and 40-50% stenosis at the cavernous segment of the right internal carotid artery (ICA). Digital subtraction angiography (DSA) was performed, which revealed stenoses in the distal segments of the bilateral internal carotid arteries, V4 segments of the bilateral vertebral arteries and at the junction of basilar artery, which were more prominent on the right side (Figure 2).
For diagnosis, usually MRI was done to confirm it. A plain X-ray may be normal or rarely makes the lesion within soft tissues visible as shading with calcifications inside and ultrasound finding is not specific enough and it does not enable diagnosis. CT scan may show a well limited mass with absorption density contained between the muscle and water. But for precise examination enable diagnosis, MRI is preferred.
The size and location of the ROI was standardized as follows: The anterior posterior margin of the ROI was manipulated to include the area from the subcutaneous fat layer to the pectoral muscle layer, and the lateral margin was adjusted to include at least 5 mm of breast tissue adjacent to the lesions, because the maximum areas of stiffness in malignant lesions were always found in the peritumoral region
The majority of benign masses are less than 4cm and if asymptomatic do not need intervention (Houtzager et al, 2013). Therefore, characterising masses as benign or malignant is essential.
An experienced board certified interventional radiologist read, analyzed and interpreted the CT venography and DSA data. Clinical presentations, compression of the left common iliac vein by the right common iliac artery, presence of collateral veins, narrowing of LCIV lumen and degree of stenosis was considered as the diagnostic criteria for diagnosing MTS. The compression level of LCIV was calculated and rated on CT using a method described by Narayan et al.(11) in which distal RCIV was used as the reference denominator to calculate the percentage of left iliac vein compression. The percentage was then used to rate compression level of LCIV as none (0%-25%), mild (>25%-50%), moderate (>50%-75%) and severe (>75%). Many studies and literature(12)
As it was referred before, the prevalence of MAL is calculated to be 10-24%, but the most of the cases remain asymptomatic. This variation in the presentation can be due to a more extensive collateral blood supply from the superior or inferior mesenteric arteries 6,7.
Arteriovenous malformations (AVMs) are currently diagnosed and treatment plan is formulated by using digital subtraction angiography (DSA) (Machet, Portefaix, Kadziolka, Robin, Lanoix & Pierot, 2012). There are some drawbacks to DSA, amongst them is the cost, patient discomfort, contrast injection and radiation exposure (Dautry, Edjlali, Roca, Rabrait, Wu, Johnson, Wieben, Trystram, Rodriguez-Regent, Alshareef, Turski, Meder, Naggara & Oppenheim, 2015). While DSA is considered to be the “Gold Standard” of care for AVMs there are studies underway to determine if brain MRA studies can obtain images
For the former, the Shapiro-Wilk test was used, and the null hypothesis that the data are normally distributed was not rejected, regardless of the feature under investigation (p-values ranging from 0.30 to 0.56). Similarly for the sphericity, the Mauchlys test was used, which again failed to reject the null hy- pothesis that the assumption of sphericity is met (p-values ranged from 0.16-0.39).