2016年 · 第96卷第45期

Abdominal aortic aneurysm (AAA) is a kind of vascular surgical disease that seriously endangers patients' lives. Abdominal aortic aneurysm resection and revascularization were once the main measures to treat abdominal aortic aneurysm. In 1997, Academician Wang Zhonghao first successfully treated infrarenal abdominal aortic aneurysm with self-developed stent-type artificial blood vessel in China, thus creating a new era of endovascular repair of abdominal aortic aneurysm (EVAR) in China. In the past 19 years in China, with the progress of endovascular treatment technology and the improvement of endovascular devices, EVAR has become the most commonly used treatment measure for abdominal aortic aneurysm in China. However, what is the current status of endovascular treatment of abdominal aortic aneurysm in various centers in China? What problems still exist, and what countermeasures may we take? Now aiming at these problems from the following aspects to try to analyze and explain.

Alzheimer's disease (AD), as a common chronic degenerative neurological disease in the elderly with cognitive dysfunction and mental behavior disorders as the main clinical features, affects daily life and social function, which brings a heavy burden to the families and society of patients. Although the basic research of AD has made great progress in recent years, clinical trials of new drugs based on the pathophysiology of AD have failed repeatedly. One of the main reasons is that most of the current drug studies are targeted at the dementia stage of AD. However, at this stage, a large number of neurons have undergone degenerative lesions or death, and it is difficult for drug intervention to reverse these lesions and achieve ideal therapeutic effect^[1]。 Therefore, it is generally believed that only early research and intervention for AD can achieve better clinical efficacy^[2]。 In 2011, the diagnostic criteria for AD introduced by the National Institute on Aging and the Alzheimer's Association, namely NIA-AA diagnostic criteria, put forward the concept of "pre-dementia stage" of AD, including clinical asymptomatic phase and mild cognitive dysfunction phase (MCI)^[3]。 The three stages of asymptomatic phase, MCI phase and dementia phase of AD were regarded as continuous pathophysiological processes of the same disease. Although the cognitive function of AD patients in the pre-dementia stage is not significantly impaired and their daily life ability is basically maintained, there are many pathophysiological changes in the brain of patients such as abnormal A β accumulation, abnormal synaptic function and abnormal phosphorylation of tau protein. The risk of MCI transforming into dementia is significantly higher than that of normal people, and about half of MCI patients will eventually develop AD^[4]。 The concept of pre-dementia stage of AD moves the research focus of AD forward and opens a new window for early diagnosis and treatment of AD.

Endovascular treatment of abdominal aortic aneurysms (EVAR) began to rise in the 1990s^[1,2]。 In the early stage, the scope of application of EVAR was very limited due to the limitations of the patient's anatomical conditions, age and equipment. Since then, the intraluminal technology has become increasingly mature, and the performance of intraluminal instruments has been continuously improved, so that the intraluminal treatment can be applied to more complex lesions, and the therapeutic effect has been improved.

Aortic aneurysms and aortic dissections are a class of diseases with extremely high mortality, usually with rupture of the aorta, ischemia of the organs and limbs, which affects life or quality of life, and even in large heart centers, the mortality rate from surgical procedures exceeds 20%. As early as 1964, Dotter put forward the concept of endovascular repair of aneurysms. Twenty-seven years later, Parodi developed the first generation of covered stents. At that time, polytetrafluoroethylene artificial blood vessels were used and fixed on metal stents, and the first case of endovascular repair of abdominal aortic aneurysm (AAA) was successfully completed, thus opening up a new era of endovascular repair of aortic diseases. Because this procedure is less invasive and has fewer complications, endovascular therapy (EVAR) has become the preferred method for the treatment of complex aortic lesions. However, those complex aortic diseases involving important branches (such as carotid artery and visceral artery) have been difficult for vascular surgeons to perform EVAR, mainly reflected in the management of superior aortic arch artery and visceral artery (VA). With the progress of the times and the development of medical material science and technology, the technique of endovascular reconstruction of branched blood vessels makes the application of endovascular grafts break through the anatomical limitations of important branched blood vessels, and turns the complete endovascular treatment of completely complex aortic aneurysm into a reality. This article will briefly describe the current progress in endovascular treatment of diseases involving important branches of the aorta.

Endovascular repair of abdominal aortic aneurysm (EVAR) has become the first choice for treatment of abdominal aortic aneurysm due to its advantages such as less trauma, quick recovery, short operation and hospital stay. Abdominal aortic aneurysms involved both unilateral and bilateral iliac arteries in 43% and 11% respectively^[1],Its treatment is difficult, and postoperative complications such as endoleak, iliac branch occlusion and tumor rupture are prone to occur. In order to reduce type IB and type II endoleak, it is necessary to extend the covered stent to the external iliac artery and embolize or occlude the internal iliac artery (ⅡA). However, various clinical complications can occur. With the continuous update of endovascular treatment equipment and technology, various methods for preserving or reconstructing ⅡA have been developed.

Case 1 male, 14 years old, developed inability to lift the left upper arm and weakness of flexing the elbow of the left upper limb without obvious trigger 3 months ago, which lasted for about 1 week and gradually relieved. Three days ago, the above symptoms were aggravated again when the left upper limb elbow support was used to operate the mobile phone, with numbness in the left upper limb and no pain. Family history denied. When he went to Qilu Hospital of Shandong University (Qingdao), the muscle strength examination showed that the left deltoid muscle was grade 3, the biceps brachii was grade 4, and the triceps brachii was grade 4. The muscle strength of the rest of the limbs was normal. Symmetric (+ +) tendon reflexes in the extremities. Sensory examination was normal, with pathological signs and high arch (-). Nerve conduction examination of left limb in external hospital at 3 months of onset (Table 1，Table 2) suggesting demyelinating sensorimotor polyperipheral neuropathy with damage to the ulnar nerve at the elbow; Electromyography suggested that the muscles innervated by C5-C7 could be seen with self-visible active denervation and re-innervation, and the damage to the superior and middle trunks of the brachial plexus was considered. Prednisone 30 mg was administered orally once daily for 2 weeks, subsequently reduced by 5 mg every week. Four months after the onset of the disease, the left upper limb function of the patients was basically restored to normal.

In recent years, stem cell transplantation has a good application prospect in tumor, trauma, degenerative diseases and other fields, and it is a hot spot in medical research. However, because traditional imaging technology cannot provide effective information on biological behavior after cell transplantation, it cannot be used as an objective basis to evaluate the effect of cell therapy, which limits the popularization of stem cell therapy in clinical practice to some extent. With the development of molecular imaging, molecular imaging technologies such as bioluminescence imaging, fluorescence imaging, radionuclide imaging and magnetic resonance imaging (MRI) can visually express complex physiological and pathological processes in the form of images from the cellular level, which provides the feasibility for stem cell tracing in vivo. Biological autoluminescence imaging and fluorescence imaging techniques have low tissue penetration power, and are currently only used in animal experiments^[1]。 Compared with radionuclide imaging, MRI has the advantages of no ionizing radiation, lower examination cost and better spatial resolution^[2], attracting more and more attention. Among them, superparamagnetic iron oxide (SPIO) as MRI probe has good biocompatibility and MRI signal sensitivity, and has been widely used in the research of stem cell tracing. Based on this, the research status of SPIO in stem cell tracing will be reviewed.

The formation of the mammalian cerebral cortex is a complex, dynamic process of change, including neuronal formation, proliferation, differentiation, migration, and synapse formation. However, the development of human brain cortex is more long and complicated. In this process, both genetic and environmental changes can affect the development of the cortex^[1]。 cortical dysplasia (CD) was first discovered in 1867. Virchow studied a 44-year-old male patient and found that there was local aggregation and expansion of cells in the cerebral cortex. He called this phenomenon ectopia. The most representative cortical dysplasia is the local cortical dysplasia common in childhood epilepsy surgery, in addition to microcephaly, multiple cerebellar gyrus, schizophrenia, etc^[2]。