Objective To study the clinical value of high frequency ultrasonography in acute closed mallet finger.Methods The high frequency ultrasonographic images of thirty-six patients with diagnosed acute closed mallet finger were retrospective analyzed.The ultrasonographic features were analyzed.Results The position and internal structure of extensor tendon could be showed by high frequency ultrasound,the position and injury level of acute closed mallet finger were identified.In 36 patients of acute closed mallet finger,6 cases were complete tear combined avulsion fracture,the ultrasonography showed the disruption in the extensor tendon at the level of the distal interphalangeal joint,the hyperechoic fracture fragment were found in the distal end of extensor tendon.22 cases were complete tear and no avulsion fracture,the longitudinal imaging showed the disruption in the extensor tendon at the level of the distal interphalangeal joint and the retraction of the tendon end.8 cases were partial tear,the ultrasonography showed that extensor tendons were thickened and hypoechoic,the section of extensor tendons were still continuous.Conclusions High frequency ultrasonography is the preferred imaging method for diagnosis of acute closed mallet finger,it will be important value for clinical treatment method.

Objective To study the value of high frequency sonography in diagnosis of peripheral nerve lipofibroma hamartoma.Methods The high frequency sonography images of seventeen patients with diagnosed peripheral nerve lipofibroma hamartoma were retrospective analyzed.The sonography features were compared with clinical surgery.Results The position and internal structure of nerve can be found by high frequency ultrasound,and which nerve fascicle,location and scope of lipofibroma hamartoma can be displayed clearly.The involved peripheral nerve was showed expansive growth.Because the hyperechoic fat tissue and hypoechoic nerve fibers alternated with one and another,the feature of high frequency sonography was lotus-like,there was no blood flow signal in nerve.Conclusions High frequency sonography is the preferred imaging method for diagnosis of lipofibroma hamartoma.

Objective To study the clinical value of color Doppler ultrasonography in the persistent sciatic artery.Methods The ultrasonographic images of eleven patients with persistent sciatic artery diagnosed by CT angiography or digital subtraction angiography were retrospective analyzed,the ultrasonographic features were summarized.Results The sciatic artery showed the enlarged internal iliac artery,which continued into the thigh in a posterior location,the sciatic artery described a tortuous course toward the knee,slowly filling normal-appearing popliteal artery in 8 cases,there were no connection with popliteal artery in 1 cases.The common femoral artery and superficial femoral artery was dysplasia in 7 patients,which was thinner than the popliteal artery.Conclusions The ultrasonography is the effective imaging method for diagnosis of the persistent sciatic artery.

Objective To evaluate the value of ultrasonography in diagnosing tendon xanthoma.Methods The ultrasonographic images of 17 patients with tendon xanthomas confirmed by surgery and pathology were retrospectively analyzed.The ultrasonographic features were summarized.Results The ultrasonographic images showed the location,number,size,shape,boundary,internal echo,involvement and blood supply of tendon xanthomas clearly.Tendon xanthomas showed hypoechoic masses within the tendons,mostly located on the extensor aspect of the hands,feet or bilateral Achilles tendons,symmetric growth,irregular-shaped and inhomogeneous,with loss of the normal fibrillar pattern in longitudinal plane.The abundant blood flow inside the tendon can be detected by color Doppler examination.Conclusions High frequency sonography is the preferred imaging method for diagnosis of tendon xanthomas.

Objective To study the diagnosis value of high frequency sonography in nontraumatic upper limb nerve torsion.Methods High frequency sonography images of thirteen patients with diagnosed nontraumatic upper limb nerve torsion were retrospective analyzed.The sonography features were compared with the clinical surgery.Results The position and internal structure of nerve can be found by high frequency ultrasound,and which nerve fascicle,location and scope of nerve torsion can be displayed clearly.The features of high frequency sonography was single or multi-segmental hourglass-like change,the two sides of nerve with hourglass like change was thickened,the echo was low,and perineurium structures in upper limb nerve was blurry.Conclusions High frequency sonography is the preferred imaging method for diagnosis of nontraumatic upper limb nerve torsion.

Objective:To investigate the value of ultrasound in the diagnosis of hourglass-like fascicular constrictions of the anterior interosseous nerve.Methods:From July 2010 to July 2020, 12 patients with hourglass-like fascicular constrictions of the anterior interosseous nerve diagnosed in Shandong Medical Imaging Research Institute Affiliated to Shandong University were retrospectively analyzed. The characteristics of the high-frequency ultrasonographic images were summarized and compared with clinical surgery.Results:The hourglass-like fascicular constrictions of the anterior interosseous nerve were all located in the median nerve of the distal upper arm in 12 patients, including 9 cases of single hourglass change and 3 cases of multiple hourglass like changes. High-frequency ultrasound can accurately locate the location of the hourglass-like fascicular constrictions of the anterior interosseous nerve and the extent of neuropathy. The sonogram of hourglass-like fascicular constrictions of the anterior interosseous nerve showed single or multiple hourglass-like changes in the median nerve of the distal upper arm. The nerve fasciculars on both sides of hourglass-like changes were thickened. There was significant difference between the diameter of the affected fascicular and the corresponding position of the contralateral fascicular[(0.20±0.04)cm vs (0.11±0.03)cm, P<0.01]. There was significant difference between the cross-sectional area of the median nerve at the widest part of the lesion side and the corresponding position of the contralateral side[(0.14±0.03)cm 2 vs (0.09±0.03)cm 2, P<0.01]. Conclusions:High-frequency ultrasound is the preferred image method for the diagnosis of hourglass-like fascicular constrictions of the anterior interosseous nerve.

Objective To evaluate the feasibility, accuracy and its clinical value of MRI-guided needle biopsy of lung lesions. Methods A total of 137 patients with pulmonary nodules or masses underwent lung biopsy in low-field open MRI equipped with iPath 200 optical tracking systems. Among them, 103 cases had solitary pulmonary lesion; the other 34 cases had multiple foci. The maximum diameter of the lesion was not smaller than 3.5 cm ( ≥ 3.5 cm) in 57 patients, between 1.5 cm and 3.4 cm( 1.5-3.4 cm) in 71 patients, not greater than 1.4 cm ( ≤ 1.4 cm) in 9 patients. Results The puncture success rate was 100.0% (57/57) for lesions ≥3.5 cm, 98.6% (70/71) for lesions 1.5-3.4 cm,77.8% (7/9) for lesions ≤1.4 cm and 97. 8% (134/137) for total cases, respectively. According to the pathological results, pulmonary lesions were malignant in 98 cases and benign in 39 cases. The sensitivity,specificity, accuracy, positive predictive value and negative predictive value of MRI-guided lung biopsy were 94.2%(98/104), 100.0% (33/33), 95.6% (131/137), 100.0% (98/98) and 84.6% (33/39),respectively. Conclusion MRI-guided needle biopsy of lung lesion can be performed precisely in a lowfield open MRI with a low risk of complications. As a supplement to US or CT-guided biopsy, it is worth further promotion and application.

Objective To explore the value of MR imaging-guided percutaneous lumbar discectomy and discolysis with oxygen-ozone mixture for treatment of posterolateral lumbar disc herniation via a new puncture approach of facet joint medial route. Methods All 114 lumbar intervertebral discs in 103 patients were diagnosed as posterolateral lumber disc herniation by CT or MRI, which were located at the levels of L3-4 in 5 cases, LA-5 in 87 cases and L5-S1 in 22 cases. The procedure was guided under 0. 23 T open magnetic resonance with iPath 200 optical tracking system. A 14 G MR-compatible needle was punctured into the disc center via a new puncture approach of facet joint medial route. The therapy steps were as follows: firstly, cut nucleus pulposus and inject 6 ml oxygen-ozone mixture of 60 μg/ml in the disc center;secondly, retreat the needle to the local prominence, cut prominent part and inject 6 ml oxygen-ozone mixture of 60 μg/ml. Thirdly, retreat the needle to the periradicular nerve root, inject 15 ml oxygen-ozone mixture of 40 μg/ml and 4 ml pain-block liquid. All patients were followed up at 3 days, 1 month, 3 months and 6 months after operation, evaluated for the effect of treatment with the modified Macnab criteria, and the results were compared with the χ2 test. Results All procedures were successfully performed. Intraoperative dural injury occurred in 5 cases. Postoperative infection of intervertebral space occurred in 2 cases. The clinical effective rate was 96. 1% (99/103), 84.5% (87/103), 94.2% (97/103), 95.1% (98/103)respectively at 3 days, 1 month, 3 months and 6 months after operation, and the differences were signifieant (χ2 = 12. 942, P = 0. 005 ) . Conclusion MR imaging-guided percutaneous lumbar discectomy and discolysis with oxygen-ozone mixture via facet joint medial route is a minimally invasive, safety and effective method for the treatment of posterolateral lumbar disc herniation.

Objective To explore the value of MR imaging-guided percutaneous cervical discectomy and discolysis with oxygen-ozone mixture for treatment of cervical disc herniation.Methods Eight herniated cervical discs in 7 patients were diagnosed by MRI, including 5 discs of lateral protruding type, 2 discs of paramedian protruding type and one disc of central protruding type.All patients underwent MR imaging-guided percutaneous cervical discectomy and discolysis with oxygen-ozone mixture.The procedures were guided by a set of 0.23 T open MR system mounted with iPath 200 optical tracking system.The herniated portion of the disc was punctured with a 14 G MR-compatible needle in the healthy side via anterolateral oblique route.The interventional steps were as follows; firstly, cut herniated part with percutaneous discectomy probe and inject 2ml oxygen-ozone mixture of 60 μg/ml; secondly, retreat the needle to the disc center, resect nucleus pulposus, and inject 2 ml oxygen-ozone mixture of 60 μg/ml.All patients were followed up for 6 months, with 4 patients by telephone and 3 patients in outpatient clinic.The effect of treatment was evaluated according to Williams postoperative assessment standard.Results All procedures were performed successfully.The clinical outcome was evaluated as excellent in 5 cases, good in 1 case and fair in 1 case.The total ratio of excellent and good was 85.7%.No serious complication occurred expect 1 case with intraoperative paroxysmal pain.Conclusion MR imaging-guided percutaneous cervical discectomy and discolysis with oxygen-ozone mixture was a safe, effective and minimally invasive method for the treatment of cervical disc herniation.

To evaluate the value of ultrasonography in diagnosing peripheral intraneural vascular anomalies . Methods The ultrasonographic images of 10 patients with peripheral intraneural vascular anomalies confirmed by surgery or pathology were retrospectively analyzed . T he ultrasonographic features were summarized . Results T he ultrasonographic images could not only clearly show the location , involvement and blood supply of peripheral intraneural vascular anomalies , but also determined the classification of them . Ultrasonography showed enlarging nerves ,within w hich tubular structures could be observed ,and the boundary between the vascular malformations and the perineurium was not clear . Abundant arteriovenous blood flow ( arteriovenous malformation) or low velocity venous blood flow ( venous malformation) within the vascular anomalies could be detected by color Doppler examination . Conclusions Ultrasonography is the preferred imaging method for diagnosis of peripheral intraneural vascular anomalies .