Automatic tumour volume delineation in respiratory-gated PET images

Introduction: Positron emission tomography (PET) is a state‐of‐the‐art functional imaging technique used in the accurate detection of cancer. The main problem with the tumours present in the lungs is that they are non‐stationary during each respiratory cycle. Tumours in the lungs can get displaced up to 2.5 cm during respiration. Accurate detection of the tumour enables avoiding the addition of extra margin around the tumour that is usually used during radiotherapy treatment planning. Methods: This paper presents a novel method to detect and track tumour in respiratory‐gated PET images. The approach followed to achieve this task is to automatically delineate the tumour from the first frame using support vector machines. The resulting volume and position information from the first frame is used in tracking its motion in the subsequent frames with the help of level set (LS) deformable model. Results: An excellent accuracy of 97% is obtained using wavelets and support vector machines. The volume calculated as a result of the machine learning (ML) stage is used as a constraint for deformable models and the tumour is tracked in the remaining seven phases of the respiratory cycle. As a result, the complete information about tumour movement during each respiratory cycle is available in relatively short time. Conclusions: The combination of the LS and ML approach accurately delineated the tumour volume from all frames, thereby providing a scope of using PET images towards planning an accurate and effective radiotherapy treatment for lung cancer.     

Medical imaging in new drug clinical development

Medical imaging can help answer key questions that arise during the drug development process. The role of medical imaging in new drug clinical trials includes identification of likely responders; detection and diagnosis of lesions and evaluation of their severity; and therapy monitoring and follow-up. Nuclear imaging techniques such as PET can be used to monitor drug pharmacokinetics and distribution and study specific molecular endpoints. In assessing drug efficacy, imaging biomarkers and imaging surrogate endpoints can be more objective and faster to measure than clinical outcomes, and allow small group sizes, quick results and good statistical power. Imaging also has important role in drug safety monitoring, particularly when there is no other suitable biomarkers available. Despite the long history of radiological sciences, its application to the drug development process is relatively recent. This review highlights the processes, opportunities, and challenges of medical imaging in new drug development.     

经皮髓核钳夹术联合臭氧治疗腰椎间盘突出症的应用研究

目的 探讨经皮髓核钳夹术(PLD)联合医用臭氧(O3)注射治疗腰椎间盘突出症后O3在椎间盘内外弥散、突出物回缩情况以及临床效果、不良反应、并发症等.方法 选择通过影像检查(CT或MR)结合临床确诊为腰椎间盘突出症的120例患者,按随机数字表法分为3组(PLD组、O3注射组、PLD+O3注射组),每组各40例,分别按方案实施治疗.结果 PLD+O3注射组腰痛发生率最低,O3在椎间盘内外弥散最好;突出物回缩率3组间无明显差异;PLD+O3注射组术后立即有效率为86%,PLD组为83%,O3注射组为35%;随访6～18个月,PLD+O3注射组总有效率为92.5%,PLD组为87.5%,O3注射组为77.5%;3组均未发生并发症.结论 PLD联合O3注射治疗腰椎间盘突出症是一种较好的综合治疗方案,安全、有效,可提高治疗效果,减少不良反应.     

选择性球囊阻断术在救治腹腔动脉-肝动脉破裂大出血的应用

内脏动脉破裂大出血可导致急性循环衰竭。用血管内球囊阻断术可迅速控制出血、为后续治疗创造条件。 作者报道2例胰-十二指肠切除术后出血患者,在做血管造影术中发生大出血、失血性休克,造影证实为腹腔动脉-肝动脉破裂,不适宜做常规栓塞治疗。通过8F导管鞘、将直径12mm的专用阻断球囊选择性插入至腹腔动脉,使出血立刻停止,经输血、补液后纠正休克。随后1例患者在持续球囊阻断下进行了手术修补、1例患者做覆膜支架置入术。2例均救治成功。 结论：选择性血管内球囊阻断术是救治凶险性内脏动脉破裂大出血的快捷有效技术,可为后续治疗赢得时间。     

介入治疗在基层医院的应用

在县级医院设备条件有限的情况下,笔者开展介入放射学工作,诊治各类患者650例,取得了满意的效果。     

未破裂输卵管妊娠的非血管介入治疗

目的探讨经输卵管途径治疗输卵管妊娠的可行性及临床疗效。方法采用介入输卵管插管方法,插管成功后注入甲氨喋呤60mg治疗16例输卵管妊娠。结果14例获得成功,2例中转手术,未出现严重并发症。结论经输卵管插管治疗输卵管妊娠是简单、安全、迅速有效的方法。     

气管内金属支架植入在肺癌治疗中的应用

目的探讨金属支架治疗肺癌导致的气管狭窄的临床疗效。方法对16例肺癌压追或侵犯气管引起的气管狭窄的患者。在纤维支气管镜的配合下,植入钛合金支架。结果所有病例支架植入后呼吸困难即刻好转,随后观察3～26个月,8例经放、化疗后仍存活,无呼吸困难及支架移位。结论金属支架植入术能缓解肺癌晚期引起的呼吸困难,改善生活质量。     

An 18-year-old man with fenestrated vertebral arteries, recurrent stroke and successful angiographic coiling

Fenestration of vertebral arteries has been reported in association with thromboembolic brain infarctions. However, few cases have been reported in which recurrent infarction occurred in spite of adequate anticoagulation. We report a young man with fenestrated vertebral arteries and stroke who failed to respond to standard anticoagulation therapy but did well with angiographic coil obliteration of an abnormal vertebral segment. An 18-year-old left-handed man presented with acute onset of dizziness and headache. No trauma or other stroke risk factors were identified. Left cerebellar infarction was seen on CT, but the cause could not be identified by brain and neck MRI, MRA, or CTA. Bilateral fenestrated vertebral arteries were identified with conventional angiography. Although the patient recovered fully and was treated with anticoagulation, he suffered a recurrent stroke 1 month later involving the right cerebellum while he was on a therapeutic dose of warfarin. Repeat arteriography showed a spontaneous dissection within one of the fenestrated vertebral segments. Since receiving angiographic coil obliteration of the pathologic segment, he has been free of all symptoms. We conclude that the patient sustained recurrent thromboembolic events in his posterior circulation due to spontaneous dissection within a fenestrated vertebral artery segment. Conventional angiography and emergent interventional embolization were essential to his diagnostic evaluation and therapeutic intervention.     

计算机系统在影像科文字档案中的应用

目的影像科电子档案系统在就诊人员文字档案中的应用价值。方法在普通电脑上安装此电子档案系统,可以规范的系统的采集、存储、查询、统计影像科就诊人员的基本情况。结果本软件囊括了影像科的全部检查项目,包括CR检查、工伤查体检查、普通放射检查、透视检查、健康查体、造影检查、职业病检查、介入检查、结核病检查等。可以利用患者姓名、X线检查号、检查部位、身份证号、就诊日期其中任一或者多个同时进行查询已注册的患者情况,还可以便利的统计科室在某段时间的经济收入。结论彻底废除了以往影像科对各种检查登记使用的表格记录本,实现了全智能化管理。达到快速登录,准确查询影像科就诊患者的全面基本情况以及科室的经济管理情况。     

Diagnosing cholangiocarcinoma in primary sclerosing cholangitis: an “evidence based radiology” review

Cholangiocarcinoma is a serious but common complication of primary sclerosing cholangitis (PSC) that is often difficult to diagnose. The aim of this study was to conduct an evidence based radiology review of the diagnostic modalities used to identify cholangiocarcinoma in patients with PSC. A systematic review of the current best evidence was carried out and a diagnostic algorithm for cholangiocarcinoma in PSC is proposed.