Magnetic resonance imaging for non-invasive clinical evaluation of normal and regenerated cartilage.

With the development of tissue engineering and regenerative medicine, it is much desired to establish bioimaging techniques to monitor the real-time regeneration efficacy in vivo in a non-invasive way. Herein, we tried magnetic resonance imaging (MRI) to evaluate knee cartilage regeneration after implanting a biomaterial scaffold seeded with chondrocytes, namely, matrix-induced autologous chondrocyte implantation (MACI). After summary of the T2 mapping and the T1-related delayed gadolinium-enhanced MRI imaging of cartilage (dGEMRIC) in vitro and in vivo in the literature, these two MRI techniques were tried clinically. In this study, 18 patients were followed up for 1 year. It was found that there was a significant difference between the regeneration site and the neighboring normal site (control), and the difference gradually diminished with regeneration time up to 1 year according to both the quantitative T1 and T2 MRI methods. We further established the correlation between the quantitative evaluation of MRI and the clinical Lysholm scores for the first time. Hence, the MRI technique was confirmed to be a feasible semi-quantitative yet non-invasive way to evaluate the in vivo regeneration of knee articular cartilage.

Experience with Esophageal Granular Cell Tumors: Clinical and Endoscopic Analysis of 22 Cases.

BACKGROUND: Esophageal granular cell tumors (GCTs) are rare tumors. Differences in reports on the clinical features of GCTs in the esophagus and some controversies about the diagnostic strategy for esophageal GCTs exist. OBJECTIVES: We aimed to investigate the clinical features and diagnosis of esophageal GCTs. Additionally, we sought to determine the prevalence of gastroesophageal reflux disease and reflux esophagitis in patients with esophageal GCTs. METHODS: We retrospectively studied the clinical features, endoscopic features, and management of 22 patients with esophageal GCTs. RESULTS: Esophageal GCTs were more common in men than in women with a ratio of 1.2:1 and were predominantly found in the distal esophagus. Ten patients with esophageal GCTs had regurgitation and/or heartburn symptoms, and eight patients were confirmed to have reflux esophagitis by endoscopy. All esophageal GCTs were protuberant lesions covered by normal esophageal epithelium. The endoscopic morphology of esophageal GCTs was diverse. On endoscopic ultrasonography, these tumors appeared as homogeneous or inhomogeneous hypoechoic lesions with clear borders originating from the submucosal or mucosal layer. Eleven patients underwent endoscopic forceps biopsy at the first endoscopy, and only six patients were correctly diagnosed by pathology. Nevertheless, the 18 lesions treated with endoscopic resection were all correctly diagnosed without complications, and no patients developed recurrence during the follow-up period. CONCLUSIONS: The occurrence of esophageal GCTs may be related to esophageal inflammation. As a method for obtaining an accurate pathological diagnosis and for treatment, endoscopic resection should be offered as the primary option for patients with esophageal GCTs.

A prospective study on endoscopic ultrasound for the differential diagnosis of serous cystic neoplasms and mucinous cystic neoplasms.

BACKGROUND: To provide criteria for the differential diagnosis of serous cystic neoplasms (SCNs) and mucinous cystic neoplasms (MCNs) by analyzing the imaging features of these two neoplasms by endoscopic ultrasound (EUS). METHODS: From April 2015 to December 2017, a total of 69 patients were enrolled in this study. All patients were confirmed to have MCNs (31 patients) or SCNs (38 patients) by surgical pathology. All patients underwent EUS examination. The observation and recorded items were size, location, shape, cystic wall thickness, number of septa, and solid components. RESULTS: Head/neck location, lobulated shape, thin wall and > 2 septa were the specific imaging features for the diagnosis of SCNs. When any two imaging features were combined, we achieved the highest area under the curve (Az) (0.824), as well as the appropriate sensitivity (84.2%), specificity (80.6%), positive predictive value (PPV) (84.2%), and negative predictive value (NPV) (80.6%). Body/tail location, round shape, thick wall and 0-2 septa were the specific imaging features for the diagnosis of MCNs. When any three imaging features were combined, we obtained the highest Az value (0.808), as well as the appropriate sensitivity (77.4%), specificity (84.2%), PPV (80.0%) and NPV (82.1%). CONCLUSIONS: Pancreatic cystadenomas that meet any two of the four imaging features of head/neck location, lobulated shape, thin wall and > 2 septa could be diagnosed as SCNs, and those that meet any three of the four imaging features of body/tail location, round shape, thick wall and 0-2 septa could be considered as MCNs. TRIAL REGISTRATION: The study was registered at the Chinese Clinical Trial Registry. The registration identification number is ChiCTR-OOC-15006118 . The date of registration is 2015-03-20.

A Prospective Study on Contrast-Enhanced Endoscopic Ultrasound for Differential Diagnosis of Pancreatic Cystic Neoplasms.

BACKGROUND AND AIMS: To determine the value of contrast-enhanced endoscopic ultrasound (CE-EUS) for differentiation of pancreatic cystic neoplasms (PCNs). METHODS: From April 2015 to December 2017, 82 patients were enrolled in this study. All patients were confirmed to have PCNs by surgical pathology. Prior to surgery, all patients underwent fundamental B-mode EUS (FB-EUS) and CE-EUS, 65 of whom underwent computed tomography (CT) and 71 of whom underwent magnetic resonance imaging (MRI). The enhanced mode data of PCNs were recorded. The diagnostic accuracy of CE-EUS in classifying PCNs was compared with that of CT, MRI and FB-EUS. The ability of CE-EUS to identify PCNs was evaluated by comparing the enhanced mode of PCNs. RESULTS: There was a significant difference between benign and malignant lesions in enhanced mode (P = 0.017). The enhanced modes of benign lesions were mostly type II and type III, while those of malignant lesions were type 0, type I, and type IV. The sensitivity, specificity, and accuracy of type 0, type I, and type IV enhanced mode as the diagnostic criterion for malignant lesions were 80%, 65.3%, and 67.1%, respectively. CE-EUS demonstrated greater accuracy in identifying PCNs than did CT, MRI, and FB-EUS (CE-EUS vs. CT: 92.3% vs. 76.9%; CE-EUS vs. MRI: 93.0% vs. 78.9%; CE-EUS vs. FB-EUS: 92.7% vs. 84.2%). CONCLUSION: Compared with CT, MRI, and FB-EUS, CE-EUS is better at differentiating PCNs. CE-EUS is expected to be another important imaging technique for the diagnosis of PCNs.

[Longitudinal evaluation of reparative cartilage after matrix-associated autologous chondrocyte implantation with delayed gadolinium-enhanced MRI of the cartilage].

OBJECTIVE: To estimate zonal variation of GAG content in reparative cartilage after matrix associated autologous chondrocyte implantation (MACI) using delayed gadolinium-enhanced magnetic resonance imaging of the cartilage (dGEMRIC). METHODS: Seven patients (14 cartilage defects) undergoing MACI were recruited for examination with dGEMRIC at 3, 6, and 12 months after the procedure to calculate global and zonal longitudinal relaxivity (Δ R1) of the normal cartilage and reparative cartilage. RESULTS: The mean Δ R1 values of normal cartilage were significantly lower than those of reparative cartilage after MACI. A significant decrease was noted in the mean Δ R1 values from the deep layer to the superficial layer in the reparative cartilage at the 3 examinations. The Δ R1 values of the reparative cartilage showed no significant variation between 3 months and 6 months, but a significant decrease in the Δ R1 values occurred at 12 months. CONCLUSIONS: dGEMRIC is feasible to assess cartilage repair noninvasively following MACI.