T1ρ technique in quantitatively evaluation on ankle osteochondral lesions of talus / 中国医学影像技术

Objective: To explore the feasibility of T1ρ technique in evaluating ankle osteochondral lesions of talus (OLT). Methods: Totally 40 patients with ankle OLT underwent both conventional MRI and T1ρ imaging, also arthroscopy examination within 1 week. Conventional MRI,arthroscopy and T1ρ imaging were observed, and ankle OLT were classified into - type (type - injury group, respectively) according to the improved Hepple classification standards. Then normal cartilage areas of 20 cases were randomly selected as the normal control group. T1ρ values of cartilage in each group were measured and analyzed. The consistency of OLT typing Results: using conventional MRI and arthroscopy was compared. Results: T1ρ images could clearly show ankle talus cartilage, and the colorific orders were different according to the degree of injuries. T1ρ values of cartilage increased with the aggravation of cartilage damage. There was no statistically difference (P=0.12) in T1ρ values of damaged cartilage of type injury group ([43.07±2.05]ms) and type Ⅱ injury group ([45.24±2.19]ms), whereas statistically differences of T1ρ values of damaged cartilage were found among other groups (P<0.05). The consistency of OLT typing Results: using conventional MRI and arthroscopy was good (Kappa=0.80, P<0.01). Conclusion: T1ρ technique can clearly display the talus cartilage of the ankle joint and quantitatively evaluate the degree of talus cartilage damage, especially for patients with early talus cartilage damage.

Morphologic variations of the fibular malleolar groove and fibrocartilaginous ridge injury on MRI with and without re-current peroneal tendon dislocation / 中华骨科杂志

Objective@#To compare the morphological variation of the fibular malleolar groove and fibrocartilaginous ridge injury in those with and without peroneal tendon dislocation using MRI.@*Methods@#Data of 45 patients (40 males, 5 females; average age 23.4±7.7 years, 11-44 years) with recurrent peroneal tendon dislocation treated from April 2010 to July 2017 and 45 patients (33 males, 12 females; average age 41.6±11.8 years, 17-67 years) without dislocation treated from June 2015 to Septem-ber 2017 were retrospectively analyzed. The morphological variation of the fibular malleolar groove and fibrocartilaginous ridge in-jury were compared between the two groups according to Rosenberg’s classification (convex, the posterior cortex of the fibula bulg-es outward; concave, the posterior fibular surface has a shallow-to-deep depression; flat, neither concavity nor convexity is found).@*Results@#In group of patients with recurrent peroneal tendon dislocation: concave, 10 patients (22.2%, 10/45); flat, 27 patients (60.0%, 27/45); convex, 8 patients (17.8%, 8/45); fibrocartilaginous ridge injury, 44 patients (97.8%, 44/45). In group of patients without peroneal tendon dislocation: concave, 16 patients (35.6%, 16/45); flat, 18 patients (40.0%, 18/45); convex,11 patients (24.4%, 11/45); fibrocartilaginous ridge injury, 13 patients (28.9%, 13/45).@*Conclusion@#According the results, significant differ-ence has not been found in morphologic variations of the fibular malleolar groove between patients with and without recurrent pero-neal tendon dislocation. Fibrocartilaginous ridge injury is common in MRI of patients with recurrent peroneal tendon dislocation.

Morphologic variations of the fibular malleolar groove and fibrocartilaginous ridge injury on MRI with and without recurrent peroneal tendon dislocation / 中华骨科杂志

Objective To compare the morphological variation of the fibular malleolar groove and fibrocartilaginous ridge injury in those with and without peroneal tendon dislocation using MRI.Methods Data of 45 patients (40 males,5 females;average age 23.4±7.7 years,11-44 years) with recurrent peroneal tendon dislocation treated from April 2010 to July 2017 and 45 patients (33 males,12 females;average age 41.6± 11.8 years,17-67 years)without dislocation treated from June 2015 to September 2017 were retrospectively analyzed.The morphological variation of the fibular malleolar groove and fibrocartilaginous ridge injury were compared between the two groups according to Rosenberg's classification (convex,the posterior cortex of the fibula bulges outward;concave,the posterior fibular surface has a shallow-to-deep depression;fiat,neither concavity nor convexity is found).Results In group of patients with recurrent peroneal tendon dislocation:concave,10 patients (22.2％,10/45);fiat,27 patients (60.0％,27/45);convex,8 patients (17.8％,8/45);fibrocartilaginous ridge injury,44 patients (97.8％,44/45).In group of patients without peroneal tendon dislocation:concave,16 patients (35.6％,16/45);flat,18 patients (40.0％,18/45);convex,11 patients (24.4％,11/45);fibrocartilaginous ridge injury,13 patients (28.9％,13/45).Conclusion According the results,significant difference has not been found in morphologic variations of the fibular malleolar groove between patients with and without recurrent peroneal tendon dislocation.Fibrocartilaginous ridge injury is common in MRI of patients with recurrent peroneal tendon dislocation.

MRI findings of joint infection and adhesion after anterior cruciate ligament reconstruction / 中国医学影像技术

Objective To analyze the joint lesions of synovial thickening after anterior cruciate ligament (ACL) reconstruction,and to explore the differences of MRI findings between joint infection and adhesion.Methods Clinical and MRI data of 25 patients with synovial thickening (11 with infections and 14 with adhesion) confirmed by arthroscopy were retrospectively analyzed.The time interval from first ACL reconstruction to the arthroscopy after ACL was 0.3-2.5 (mean[1.1±0.6]) months and 6.0-19.0 (mean[11.0±4.9]) months,respectively.Results The lesions caused synovial thickening on MRI included joint infection and joint adhesion.MRI findings of joint infection included synovial thickening,moderate to massive joint effusion,different degrees of soft tissue swelling,bone marrow edema of distal femur and proximal tibia,ACL graft continuous fiber (high signals in 5 patients) and bone tunnel pseudo widened in 5 patients,while of joint adhesion included synovial thickening,striped short T2 signals in part of the thickened synovium on suprapatellar bursa,medial and lateral recess,the infrapatellar fat pad and the intercondylar fossa,without or only a small amount of joint effusion,ACL graft continuous,as well as high signals and rough edge in 3 patients,while bone tunnel was not significantly widened.Statistical differences of joint effusion,soft tissue swelling,edema of bone marrow and bone tunnel pseudo widened were found between joint infection and joint adhesion (all P＜0.05).Conclusion MRI findings of joint infection mainly included synovial thickening,joint effusion and high signal of joint cavity,while of joint adhesion were synovial thickening,equal or slightly high signal of joint cavity.Joint infections mainly occurred in the early stage after operation,while joint adhesions mainly occurred in the middle and late stage after operation.

Comparison of T1ρ,MR and arthroscopy in the diagnosis of knee joint cartilage / 实用放射学杂志

Objective To explore the value of T1ρin the diagnosis of knee osteoarthritis(OA),and to compare the diagnostic ability of T1ρ, MR and arthroscopy for early patellar cartilage injury.Methods 28 patients underwent T1ρMR imaging.We processed the images and measured T1ρvalues of the normal and damage cartilage.All cases were recorded results of MR and arthroscopy.Results T1ρ sequence could show cartilage clearly,and performed different colour levels,T1ρvalues of normal cartilage were less than 50 ms,and increased with aggravation of cartilage injury.The differences ofⅠ-ⅡandⅢ-Ⅳhad statistically significant.9 cases in grade 0 under MR and arthroscopy performed high values in T1ρ,which similar to gradeⅠ-Ⅱinjury,the diagnosis sensitivity of T1ρfor early cartilage injury was higher than MR and arthroscopy.In addition,arthroscopy and MR had high consistency in the diagnosis of cartilage.Conclusion T1ρcan effectively predict early cartilage injury and knee OA non-invasively,and can detect early cartilageinjury before MR and arthroscopy.

Hearing Improvement in A/J Mice via the Mouse Nerve Growth Factor

OBJECTIVES: To investigate the otoprotective effects of mouse nerve growth factor (mNGF) in A/J mice. METHODS: The mice at postnatal day 7 (P7) were randomly separated into a mNGF treated group (mNGF group) and a distilled water (for injection) treated group (control group). The mNGF dissolved in distilled water or distilled water alone was given to the mice once every other day from P7 by intramuscular injection in the hips. The otoprotective effects of mNGF in A/J mice were observed in a time course manner. The thresholds of auditory-evoked brainstem response (ABR) were tested from the age of the 3rd to the 8th week. Sections of the inner ears were stained by hematoxylin and eosin, and spiral ganglion neurons (SGNs) were observed at the age of the 3rd, the 6th,and the 8th week. Counts of whole mount outer hair cells (OHCs) in the cochleae were made at the age of 8 weeks. Expression of apoptosis related genes was determined by quantitative real-time polymerase chain reaction and Western blotting. RESULTS: ABR thresholds of the mNGF group were significantly lower than those of the control group at the age of the 6th and the 8th week. Moreover, the mNGF preserved OHC and SGN in the mouse cochleae in this period. Further experiments showed that the expression of caspase genes (including caspase-3) was inhibited in the mouse inner ears in the mNGF group. CONCLUSION: The mNGF improves hearing in A/J mice by preserving SGN and OHC in the cochleae.

MRI findings of anterior cruciate ligament graft tear / 中华放射学杂志

Objective To summarize MRI features of anterior cruciate ligament graft tear and to explore the differences of MRI findings between acute tear and chronic tear, and compare the diagnostic ability of MRI and clinical examinations for graft tear. Methods MR images of 43 patients (44 knees) with anterior cruciate ligament graft tear(40 complete tear, 4 partial tear)confirmed by secondary arthroscopy were retrospectively analyzed. There were 18 acute tear and 26 chronic tear. Primary and secondary signs reported with conventional anterior cruciate ligament tear were adopted to evaluate graft tear. The exact probability method was used to compare the prevalence difference between various direct and indirect signs and the χ2 test was used to compare the accuracy between MRI and physical examination. Results The primary signs in MR images of anterior cruciate ligament graft tear included graft discontinuity in 13 kness, graft thickening with edematous high signal intensity in 12 knees, decreased slope of graft fibers in 6 kness, graft disappearing in 5 knees, and distinct graft atrophy in 3 knees. The secondary signs included kissing bone contusion in 4 knees, posteriorcruciate ligament buckling in 3 knees, increased anterior tibial displacement in 2 knees, bone contusion of the lateral condyle of femur, and bone contusion of thetibia condyle in 1 knee, respectively. There were no significant differences regarding the proportion of each sign between acute and chronic graft tear. Accuracy of MRI, Lachman test, and anterior drawer test were 87.5%(35/40), 95.0%(38/40)and 95.0%(38/40), respectively, which were all significantly higher than that of pivot shift test(42.5%,17/40) with significant differences(χ2=17.80, P<0.0083). Conclusions MRI is sensitive for diagnosing anterior cruciate ligament graft tear, the primary signs is the main evidence for the diagnosis of ACL graft tear, but it is hard to distinguish acute and chronic graft tear based on MR findings. The diagnostic accuracy has no statistically significant differences among MRI, Lachman test, and anterior drawer test, but they are all higher than pivot shift test.