2015年 · 第49卷第09期

Percutaneous gastrostomy can provide adequate enteral nutrition for patients with dysphagia, which can be performed under endoscopic, X-ray and CT guidance^[1,2,3]。 However, for esophageal cancer patients with severe stenosis of the lesion segment, endoscopy cannot pass through the stenosis segment, and endoscopic percutaneous gastrostomy is difficult to perform; X-ray guidance can only obtain two-dimensional DSA images, and it is difficult to judge the relative position of the puncture needle and the gastric cavity. It is not suitable for patients with left hepatomegaly or small gastric cavity. CT guidance cannot monitor the position of the puncture needle in real time, and cannot dynamically observe the gastric cavity, which is prone to withdrawal of the puncture needle from the gastric cavity and poor filling of the gastric cavity. C-arm CT is a new function of flat-panel DSA angiography system, which is a rapid reconstruction of three-dimensional DSA images obtained after rotating DSA X-ray tube twice into axial simulation CT images^[4]。 The author performed percutaneous gastrostomy in 13 patients with advanced esophageal cancer with severe lesion segment stenosis under the guidance of C-arm CT, and the curative effect was satisfactory, as reported below.

Male, 12 years old, was seen on 12 November 2013 due to sudden unconsciousness and paroxysmal limb twitching. The child suddenly suffered from asthma with unconsciousness and urinary incontinence 7 hours ago. After a few minutes, the asthma was relieved and his consciousness slightly improved. However, sudden eyes turned up, lips were blue, limbs twitched, accompanied by sweating all over the body, the convulsions stopped for several minutes, consciousness gradually improved, and symptoms of headache and dizziness appeared. Physical examination: The child is conscious, poor spirit, bilateral pupils are equal size and round, light reflex is slightly dull, eye movement is flexible, vision is normal, limb muscle strength is grade V, neck is soft, and bilateral Babinsky sign is suspected positive.

A 22-year-old male, who had occasional pain in the left occipital region for 8 years and gradually worsened for 5 days, came to the doctor on March 13, 2013. The patient's physical examination showed no obvious abnormalities. CT examination also showed no abnormalities. Plain and enhanced MRI scans of the head: An oval long T of 2.5 cm ×2.5 cm ×3.0 cm was seen between the subdural and cerebellar hemisphere of the left posterior cranial fossa₁（Figure 1), slightly longer T₂Signal, T₂The WI signal is still uniform, and there are vaguely fuzzy dot-like slightly higher signals. DWI (Figure 2) showed uniform low signal changes, the edge of the lesion was clear, the cerebellar hemisphere was compressed, and the adjacent subarachnoid space was widened. The peripheral annular enhancement of the tumor was obvious on MRI enhancement scan, and the central spot-like weak enhancement (Figure 3）。 MRI diagnosis of meningioma is highly likely.

Female, 7 years old, was seen on October 25, 2013 due to repeated abdominal pain for more than 3 months and aggravated for 1 1/2 months. Physical examination: Obvious tenderness in the left costal area under the xiphoid process. Abdominal B-ultrasound: A heterogeneous hypoechoic mass was seen in the left middle and upper abdomen, irregular and unclear, with a size of about 5.6 cm ×4.3 cm ×6.7 cm. The surrounding mesangium was swollen, and the superior mesenteric artery passed through the lesion. Consider infectious lesions or tumors. CT examination: A soft tissue density mass was seen in the left middle and upper abdomen, with irregular shape and uneven density. The CT value was 16~35 HU, with unclear edges, and the size was basically the same as the B-ultrasound examination. The surrounding mesangium was swollen. The enhancement scan showed uneven enhancement of the tumor, and no enhancement was seen in its low density (Figure 1）； The superior mesenteric artery and its branches pass through it, become thinner, and expand proximally; Irregular thickening and twisting of the superior mesenteric vein. Consider that the tumor may be large, and infection is not excluded. After 1 week of anti-inflammatory treatment, MRI examination showed that the size of left middle and upper abdomen was similar to that before, and the signals were mixed, with slightly longer T₁And slightly longer T₂Signals are dominant, and small patches of short T can be seen in it₁（Figure 2), short T₂Signal, the boundary between the lesion and the surrounding intestine is poor, and the adjacent mesentery is swollen; DWI lesions showed slightly mixed hyperintensity, and ADC diagram was mainly low intensity, with ADC value of 0.99×10^-3mm²/s. Enhancement scan: Spot-like mild enhancement was seen outside the early lesion in the enhancement stage. With time, the enhancement around the lesion increased slightly and gradually filled centripetally (Figure 3), and the low signal region is still seen inside after 15 minutes; Medium and local thinning of the passing lesion of the superior mesenteric artery. Consider vascular malignancy may be large.

Motor dysfunction is the most common symptom of acute cerebral infarction, especially the effect of opponent's motor function is the most common^[1]。 However, regardless of whether patients receive rehabilitation treatment or not, their motor function will recover to varying degrees, and this spontaneous functional recovery is attributed to cortical function reorganization within motor network, but the specific mechanism is still unclear. The motor network mainly includes bilateral primary motor area (M1), premotor cortex (PMC) and supplementary motor area (SMA)^[2]。 The understanding of the recovery mechanism of motor function after cerebral infarction will help clinicians to formulate more reasonable rehabilitation treatment plan to make patients get the most recovery. Therefore, a large number of studies have focused on the recovery mechanism after cerebral infarction^[1,3,4]。 Conventional DWI has been widely used in the diagnosis of cerebral infarction, but its role in studying the mechanism of infarction recovery is very limited^[5]。 With the development of MRI, especially the emergence and development of fMRI technology based on blood oxygenation level dependent (BOLD), people can observe the relationship between the degree of motor system damage and functional reorganization during the recovery of cerebral infarction from the perspective of neuronal activity, and explore the mechanism of motor function recovery^[6]。 The fMRI research methods aiming at the recovery mechanism of cerebral infarction mainly include the study of local brain activity and the study of brain intersection connection pattern. The research methods of local brain activity mainly include task-induced fMRI, amplitude of low frequency fluctuation (ALFF)^[4]And regional homogeneity (ReHo)^[1]。 The study of interbrain connectivity patterns mainly includes resting-state functional connectivity (rsFC)^[3,7]And effector connections that respond to dynamic causality between brain regions^[8]。 The author reviewed and analyzed various fMRI studies on motor function recovery after cerebral infarction, and summarized the possible mechanism of motor function recovery.