Objective To evaluate the MRI findings of achilles tendon rupture. Methods The MRI data of 7 patients with achilles tendon rupture were retrospectively analysed. All 7 patients were male with the age ranging from 34 to 71 years. Routine MR scanning was performed in axial and sagittal planes, including T_1WI,T_2WI and a fat suppression MRI(SPIR).Results Among 7 patients, complete achilles tendon rupture was seen in 6 cases, partial achilles tendon rupture 1 case. The site of tendon disruption were 2.6-11.0 cm(mean 5.4 cm)proximal to the insertion in the calcaneus. The MRI findings of a partial or complete rupure of the achilles tendon included enlarged and thickened achilles tendon (7 cases),wavy lax achilles tendon(2 cases),discontinuity of some or all of its fibers and intratendinous regions of increased signal intensity(7 cases).In the cases of complete tendon rupture,the size of the tendinous gap varied from 3.0-8.0 mm,which was filled with blood and appeared as edema of increase signal intensity on T_2WI and SPIR.In all 7 patients, MR scanning showed medium signal intensity(7 cases)on T_1WI,or medium signal intensity(1 cases),medium-high signal intensity(3 cases),hish signal intensity(3 cases)on T_2WI,and medium-high singnal intensity(2 eases),high signal intensity(5 cases)on fat suppression MRI. The preachilles fat pad showed obscure in 6 cases of complete achilles tendon rupture. Conclusion MRI is an excellent method for revealing achilles tendon rupture and confirming the diagnosis.

Objective To evaluate the diagnostic value of computed tomographic(CT) guided percutaneous fine-needle aspiration biopsy(FANB) in mediastinal lesions.Methods The authors retrospectively reviewed the records of 104 patients of the mediastinal lesions who underwent CT guided percutaneous fine-needle aspiration biopsy.The sites of CT guided biopsy in 104 patients included anterior mediastinum(n = 73) ,middle mediastinum(n = 29) and posterior mediastinum(n = 2) .The mediastinal lesions with variation in size from 2.31 cm ? 1.11 cm ～ 14.5 cm ? 10.3 cm(

Objective To evaluate the influence of lesion size and depth on the diagnostic accuracy and the rate of pneumothorax in patients undergone CT-guided transthoracic aspiration biopsy for pulmonary lesions.Methods CT-guided percutaneous transthoracic biopsy was performed in 398 patients that had surgical resection or clinical follow-up.According to lesion size,lesions were divided into≤2 cm,2～4 cm and ≥4 cm.Lesion depth was measured from the pleura surface to the edge of the lesion.This depth was classified in three categories:≤1 cm,1～3 cm and ≥3 cm.Comparison of the diagnostic accuracy and the frequency of pneumothorax in different size and depth of lesion was performed.Results(1)The overall diagnostic accuracy of CT-guided percutaneous needle aspiration biopsy was 83.2%(331/398).Pneumothorax occurred in 58(14.6%)of 398 biopsy;(2)The diagnostic accurate rate in different size of lesion was 73.3%(44/60),81.5%(176/216)and 91.0%(111/122)respectively,?2=9.91,P0.05.The occurred rate of pneumothorax in different depth lesion was 2.8%(4/141),14.8%(21/142)and 28.7%(33/115),?2=34.03,P

Objective To analyse our clinical experience with CT guided percutaneous renal cysts puncture and ethanol therapy.Methods Five hundred and ten renal cysts in 445 patients were undergone CT guided percutaneous renal cysts puncture and ethanol therapy. Among the 445 cases, 385 cases had solitary renal cyst, 53 multiple renal cysts, and 7 polycystic kidneys. The renal cysts varied in size from 1.9 to 13.5cm in diameter. The amount of aspirated fluid varied from 3 to 780ml. A 18-21 gauge aspiration needles were used for all patients. A 25.0% cyst volume replacement with 99.7% ethanol was approved to be appropriate. Results 427 renal cysts in 396 patients were followed up by computed tomographic (CT) or ultrasound for less than 3 months to more than one year duration. The curative effective rate and disappearance rate of the renal cystic cavity in solitary renal cysts were 97% and 82%, respectively. In multiple renal cysts, the corresponding values were 95% and 79%. In polycystic kidneys, the curative rate was 67%. The complications such as local abdominal pain (28 cases) and hematuria (four cases) were observed in this series. There were no fatal complications. Conclusions CT guided percutaneous renal cyst puncture and ethanol therapy is an useful procedure for the treatment of solitary renal cysts and multiple renal cysts.

Objective To evaluate the MR findings of normal and abnormal collateral ligament. Methods The MR findings of 56 normal and 36 surgically confirmed injured collateral ligaments were retrospectively reviewed and compared. Results The normal tibial and fibular collateral ligaments were hypointense string on both T 1 and T 2 coronal MR images, with an average length of 6.8 cm for tibial collateral ligament and 5.7 cm for fibular collateral ligament. 36 collateral ligaments were injured, including 18 tibial and 12 fibular collateral ligaments. Three cases (6 ligaments) had both tibial and fibularcollateral ligaments injuries. The injury of collateral ligament was classified as: Grade I (18 ligaments), Grade Ⅱ (11 ligaments), and Grade Ⅲ (7 ligaments). The complications of anterior cruciate ligament sprains (13 cases), posterior cruciate ligament sprains (9 cases), meniscal tears (12 cases), bony contusion and fracture (7 cases), and joint effusion (20 cases) were found in 25 patients(78%). Conclusion Coronal MR imaging can clearly demonstrate the structure of the knee collateral ligaments, accurately diagnose and classify the ligament injury, and correctly detect the complications. MRI should be used as a routine examining method for knee trauma.

Objective To investigate the factors influencing the diagnostic accuracy in CT-guided percutaneous transthoracic aspiration biopsy of lung lesions. Methods CT-guided percutaneous transthoracic biopsy was performed in 435 patients with surgical pathologic confirmation or clinical follow-up.Univariant statistical analysis and multivariant stepwise Logistic regression analysis were used to study the influence of lesion-related factors(benignancy or malignancy,size,location,depth,presence of cavity),procedure factors(laser-guidence,position of patient) and patient-related factors(sex,age,presence of emphysema);with the accuracy of the diagnosis. Results ① 289 lesions were diagnosed as malignant ones and 146 as benign ones.The accuracy of CT-guided biopsy was(83.4%)(363/435).Univariant analysis showed that the diagnostic accuracies for malignant and benign lesions were(88.9%)(257/289) and(72.6%)(106/146),respectively(?~2=(18.71),P=(0.00002)).Laser-group was superior to non-laser group((88.4%) versus(80.9%),respectively,?~2=(4.00),P=(0.0456)).Mean diameters of lesions in correct diagnostic group and non-correct diagnostic group were(3.78)?(1.64) cm and(3.02)?(1.26) cm,respectively((F=)(13.79),P=(0.0002)).②Multivariant stepwise Logistic regression analysis showed that among the various factors influencing the final benign or malignant diagnoses(Wald ?~2=(14.01),P=(0.0002)) and using laser-guidence(Wald ?~2=(3.92),P=(0.0477)) were significantly associated with the diagnostic accuracy. Conclusions Final correct diagnoses(benign,malignant) are closely related to the application of laser-guidence for determining the diagnostic accuracy in CT-guided transcutaneous thoracic needle aspiration biopsy.

Objective To evaluate CT-guided pereutaneous biopsy and fine needle aspiration in diagnosing malignant musculoskeletal tumors. Methods CT-guided percutaneous biopsy and fine needle aspiration was performed in 106 cases with suspected musculoskeletal tumor. The pathological results obtained from biopsy specimens were compared with clinical final pathological diagnoses. Results All 106 cases were finally diagnosed as suffering from malignant musculoskeletal tumors, which were proved by operation and incisional biopsy. Of 106 cases receiving CT-guided percutaneous biopsy and needle aspiration, the pathologic diagnosis obtained from this procedure was consistent with the clinical final pathological diagnosis in 89 and was "negative" in 17, with an accuracy rate of 84.0%. Conclusion CT-guided percutaneous biopsy and fine needle aspiration is a safe, simple and effective technique for the diagnosis of malignant musculoskeletal tumors, Incisional biopsy may be necessary when this procedure gives "negative" result.

Objective To evaluate CT-guided percutaneous biopsy and fine needle aspiration in diagnosing malignant musculoskeletal tumors.Methods CT-guided percutaneous biopsy and fine needle aspiration was performed in 106 cases with suspected musculoskeletal tumor.The pathological results obtained from biopsy specimens were compared with clinical final pathological diagnoses.Results All 106 cases were finally diagnosed as suffering from malignant musculoskeletal tumors,which were proved by operation and incisional biopsy.Of 106 cases receiving CT-guided percutaneous biopsy and needle aspiration,the pathologic diagnosis obtained from this procedure was consistent with the clinical final pathological diagnosis in 89 and was "negative" in 17,with an accuracy rate of 84.0%.Conclusion CT-guided percutaneous biopsy and fine needle aspiration is a safe,simple and effective technique for the diagnosis of malignant musculoskeletal tumors.Incisional biopsy may be necessary when this procedure gives "negative" result.

Objective To observe the brain abnormalities of the white matter and myelination in patients with BH4 deficiency using MRI examination, and to further estimate the effect of treatment. Methods Eleven patients with BH4 deficiency aged 17 weeks to 4 years were observed, including 9 cases who were detected by newborn screening program. Although those patients were treated with low phenylalanine diet, and the blood phenylalanine 1evels maintained to 120-240 ?mol/L, the patients presented progressive hypotonia, convulsion, and mental retardation. All cases were diagnosed as BH4 deficiency by analysis of urinary pterins profile, BH4 loading test, and determination of dihydropteridine reductase in RBC. The patients received MRI examination using a 0.5 T MR system. Results Delayed myelination was found in 11 cases (100%) in frontal lobe, 8 cases (72.2%) in occipital lobe, 4 cases (36.3%) in temporal lobe, and 3 cases (27.3%) in parietal lobe. Delayed myelination of corpus callosum could be found in 6 cases (54.5%). There were abnormal diffuse high signals in the white matter on T_2WI in all cases. Conclusion Patients with BH4 deficiency demonstrate a high occurrence of brain abnormalities in the white matter. Those abnormalities are related not only with hyperphenylalaninemia, but also due to the decreased synthesis of neurotransmitters, such as L-Dopa and 5-HTP, all of these could be the reasons of adverse effect of the development of white matter.

Objective To prospectively assess the therapeutic procedure and outcome of MR-guided percutaneous sclerotherapy in patients with venous vascular malformations of the extremities. Methods Fifty-seven percutaneous sclerotherapy treatments were performed under MR guidance in 28 patients with venous vascular malformation. Assessment was conducted to analyze (1) individual success of therapy, (2) improvement of clinical symptoms, ( 3 ) occurrence of complications, (4) volume changes at follow-up examinations, (5) contrast-to -noise ration (CNR) changes. Paired-t test was used to compare the volume and CNR of pre- and postintervention. Results All MR-guided percutaneous sclerotherapy were performed successfully and without serious complications. Individual predominant symptoms were improved, especially about the pain and functional impairment. The mean lesion volumes of pre- and post-intervention were (56. 8 ± 11.7 ) cm3 and ( 27.0 ± 7.2 ) cm3 respectively, which showed significant difference ( t = 8. 90, P < 0. 01 ). The percentage of volume shrinkage ranged from 28. 5% to 74. 4% [ mean ( 54. 4 ± 5. 3 ) % ]. The CNR of the pre and post-interventional images were 21.9 ± 2. 0 and 8.4 ± 0. 9 respectively. There was significant difference(t = 21.76, P < 0.01 ) between them, and the percentages of CNR decrease were 40.0% to 78. 0% [ the mean(61.0 ± 3.6)%]. Conclusion MR-guided sclerotherapy of venous vascular malformations of the extremities is a safe and efficient technique.