Diffusion weighted magnetic resonance imaging (DWI) is an imaging technique which provides tissue contrast by the measurement of diffusion properties of water molecules within tissues. Diffusion is expressed in an app...Diffusion weighted magnetic resonance imaging (DWI) is an imaging technique which provides tissue contrast by the measurement of diffusion properties of water molecules within tissues. Diffusion is expressed in an apparent diffusion coefficient (ADC), which reflects the diffusion properties unique to each type of tissue. DWI has been originally used in neuroradiology. More recently, DWI has increasingly been used in addition to conventional unenhanced and enhanced magnetic resonance imaging (MRI) in other parts of the body. The reason for this delay was a number of technical problems inherent to the technique, making DWI very sensitive to artifacts, which had to be overcome. With assessment of ADC values, DWI proved to be helpful in characterization of focal liver lesions. However, DWI should always be used in conjunction to conventional MRI since there is considerable overlap between ADC values of benign and malignant lesions. DWI is useful in the detection of hepatocellular carcinoma in the cirrhotic liver and detection of liver metastases in oncological patients. In addition, DWI is a promising tool in the prediction of tumor responsiveness to chemotherapy and the follow-up of oncological patients after treatment, as DWI may be capable of detecting recurrent disease earlier than conventional imaging.This review focuses on the most common applications of DWI in the liver.展开更多
目的:腮腺深叶良性肿瘤(benign deep lobe parotid tumors,BDLPTs)具有多种临床表现和影像学特征,与选择合适的手术入路密切相关,本研究旨在探讨不同类型BDLPTs手术方式的差异。方法:选取2014年8月—2020年8月因腮腺区肿物就诊于北京大...目的:腮腺深叶良性肿瘤(benign deep lobe parotid tumors,BDLPTs)具有多种临床表现和影像学特征,与选择合适的手术入路密切相关,本研究旨在探讨不同类型BDLPTs手术方式的差异。方法:选取2014年8月—2020年8月因腮腺区肿物就诊于北京大学口腔医院并行手术治疗且病理诊断为BDLPTs的75例患者,回顾性评估CT影像资料,根据肿瘤与各种结构的解剖关系将BDLPTs分为4类,探讨每种类型肿瘤的手术治疗方法。采用SPSS 24.0软件包对数据进行统计学分析。结果:Ⅰ型BDLPTs(14/75,18.7%)完全位于下颌支和茎突下颌间隙内侧,瘤体增大时突向咽旁间隙。Ⅱ型BDLPTs(19/75,25.3%)位于下颌后间隙,以下颌支、茎突下颌间隙、乳突和下颌后静脉为界。Ⅲ型BDLPTs(27/75,36.0%)呈膨胀型生长,横穿茎突下颌间隙,从下颌后静脉延伸至咽旁间隙。Ⅳ型BDLPTs(15/75,20%)位于耳垂下方、面神经和下颌后静脉深部。经下颌骨劈开入路主要用于Ⅰ型病例(10/14),Ⅲ型病例采用腮腺入路(14例)、下颌入路(11例)和腮腺-下颌联合入路(2例),Ⅱ型和IV型病例经腮腺入路同时行腮腺切除术。结论:BDLPTs分类可为术前制定治疗计划提供有价值的见解和实践指导。展开更多
Hemangiomas are the most frequent benign tumors of the liver. Most hemangiomas are asymptomatic and therefore largely diagnosed only in routine screening tests. Usually they are small and require no specific treatment...Hemangiomas are the most frequent benign tumors of the liver. Most hemangiomas are asymptomatic and therefore largely diagnosed only in routine screening tests. Usually they are small and require no specific treatment. In some situations they can reach great dimensions, causing some discomfort to the patient. Resection of liver hemangioma is indicated in cases of great dimension tumors causing symptoms such as pain, nausea or bloating caused by compression of adjacent organs. We report a case of a rare giant hemangioma with rapid growth in short time:a 50 year old female reported to our institution with a 40 cm giant liver hemangioma and then underwent a left hepatectomy.展开更多
文摘Diffusion weighted magnetic resonance imaging (DWI) is an imaging technique which provides tissue contrast by the measurement of diffusion properties of water molecules within tissues. Diffusion is expressed in an apparent diffusion coefficient (ADC), which reflects the diffusion properties unique to each type of tissue. DWI has been originally used in neuroradiology. More recently, DWI has increasingly been used in addition to conventional unenhanced and enhanced magnetic resonance imaging (MRI) in other parts of the body. The reason for this delay was a number of technical problems inherent to the technique, making DWI very sensitive to artifacts, which had to be overcome. With assessment of ADC values, DWI proved to be helpful in characterization of focal liver lesions. However, DWI should always be used in conjunction to conventional MRI since there is considerable overlap between ADC values of benign and malignant lesions. DWI is useful in the detection of hepatocellular carcinoma in the cirrhotic liver and detection of liver metastases in oncological patients. In addition, DWI is a promising tool in the prediction of tumor responsiveness to chemotherapy and the follow-up of oncological patients after treatment, as DWI may be capable of detecting recurrent disease earlier than conventional imaging.This review focuses on the most common applications of DWI in the liver.
文摘Hemangiomas are the most frequent benign tumors of the liver. Most hemangiomas are asymptomatic and therefore largely diagnosed only in routine screening tests. Usually they are small and require no specific treatment. In some situations they can reach great dimensions, causing some discomfort to the patient. Resection of liver hemangioma is indicated in cases of great dimension tumors causing symptoms such as pain, nausea or bloating caused by compression of adjacent organs. We report a case of a rare giant hemangioma with rapid growth in short time:a 50 year old female reported to our institution with a 40 cm giant liver hemangioma and then underwent a left hepatectomy.
