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Precise localization of the needle tip during CT-guided percutaneous biopsy is considered to be a key element of a successful procedure. To ensure accuracy, the true needle tip must be differentiated from a false or simulated tip which appears when the CT slice encompasses only the shaft of an angled needle. By obtaining images of an aspiration biopsy needle inserted vertically into a phantom and then incrementally tilting the gantry, the authors were able to compare the characteristic features of the true tip to the simulated tip. The true tip was abrupt and distinct and had an adjacent flame-like low density artifact. The simulated tip was indistinct and tapered, yet still produced the adjacent artifact. We concluded that the shape and distinctness of the end portion of the needle itself, rather than the attendant artifact, were the most reliable criteria for accurate needle tip identification. 相似文献
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目的:比较多层螺旋CT(multi-slice spiral CT,MSCT)与核磁共振血管成像(MRA)、数字减影(DSA)对主动脉夹层(aortic dissection,AD)的诊断价值。方法:对17例AD患者行MSCT检查,并与MRA、DSA的检查结果进行比较。结果:对17例AD患者用MSCT、MRA、DSA都能作出诊断(按DeBakey分型,Ⅰ型有4例,Ⅱ型有1例,Ⅲ型有12例),但只有MSCT能明确显示夹层的范围和分支的受累情况,以及剥离内膜瓣、裂口及主动脉的周围情况。而MRA对裂口的检出率只有21.74%,DSA可达87.0%。结论:MSCT对AD的分型以及破裂口的定位诊断更具准确性,对动脉分支显示更清晰。 相似文献
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Soo-Young CHOI Woo-Chang JEONG Young-Won LEE Ho-Jung CHOI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):239-244
Contrast enhanced ultrasound (CEUS) is useful to evaluate tissue perfusion in the kidney. In veterinary
medicine, sedation or anesthesia may be required in uncooperative or panting patients. The aim of this study
was to evaluate and compare the normal kidney perfusion patterns in conscious and anesthetized dogs using
CEUS. Eight healthy beagles were used in this study. Scanning was performed in conscious dogs using manual
restraint (conscious group), or under general anesthesia using tiletamine-zolazepam and medetomidine (TZM
group) or medetomidine (M group). The contrast agent (Sonovue®) was administered as an IV bolus.
The peak intensity (PI), time to peak enhancement from injection (TTP0) and the time to peak
enhancement from the initial rise (TTPup), upslope, downslope and area under the curve (AUC) were
analyzed. Compared to the cortical values in the conscious group, TTP0 was significantly delayed in
the TZM group, and upslope, TTP0 and TTPup were significantly different in the M group.
The AUCs in the TZM and M groups were not different from those in the conscious group. The upslope of renal
medullary perfusion was significantly decreased in the TZM and M groups. TTP0 and TTPup
were also significantly delayed in these groups. The AUC of the medulla was significantly decreased in the M
group. Therefore, TZM is useful as an anesthetic protocol when performing CEUS, and the obtained data may
serve as reference values in the evaluation of renal perfusion using CEUS in dogs under anesthesia. 相似文献
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Amalia Agut Juana D. Carrillo Agustina Anson Eliseo Belda Marta Soler 《Veterinary radiology & ultrasound》2016,57(3):E30-E33
A young intact female dog was presented with urinary incontinence. Abdominal ultrasound revealed the presence of hyperechoic linear structures within the cranial vagina suggestive of foreign material. A computed tomography (CT) retrograde vaginourethrogram demonstrated the presence of a fistulous tract between the urethra and vagina. A presumptive diagnosis of urethrovaginal fistula due to migration of foreign material was made. The grass awn was removed with vaginoscopic‐guided retrieval. Fourteen days later, surgical repair of the fistula and an ovariohysterectomy were done. This case report emphasizes the usefulness of CT for diagnosis and precise anatomical localization of genitourinary tract fistulas. 相似文献
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