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The article introduces a new kind of waterproof equipment for endoscope. The equipment can resolve the problem that the endoscope's ocular and camera are always interfered by the Backstreaming liquid while performing surgical operation. The equipment is made up of three parts, which are ring-shaped locking structure, obturating ring and waterproof plastic sheath. Using the equipment can achieve the purpose of protecting the endoscope's ocular and camera effectively.
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Endoscopes , Equipment Design , Protective DevicesABSTRACT
Purpose To judge the value of CT in the diagnosis of acute pancreatitis. Methods 74 cases of acute pancreatitis confirmed by operation were reviewed. All patients underwent CT plain and contrast -enhanced scanning. Oral contrast agents were used. Results According to clinical diagnosis, they were devided into edematous type(n=53),and necrotic type(n=21). 7 cases were complicated with abscesses, and 5 cases died. According to CT finding, Grade A,n=10; Grade B,n=16; Grade C,n=19; Grade D,n=16; Grade E, n=13. Conclusion CT is valuable in the diagnosis of acute pancreatitis, and CT grade is referable.
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Objective To summarized the diseases which were demonstrated as hyperintensity lesions on high diffusion sensitive gradien(high b value) diffusion weighted imaging(DWI) To investigate the differential diagnosis of the diseases and to discuss the corresponding biophysics mechanism Methods 90 cases were studied, which were clinically highly suspected of brain ischemic stroke onset and in which hyperintensity lesions were demonstrated on DWI The patients were divided to 2 groups according to the time between the onset and the MR examination:group A(1 5-6 0 h)with 13cases, group B(7 h to 8 d)with 77cases The appearances of the lesions on conventional MRI, ADC values and anistropy(CV )of the lesions were studied Results hyperintensity lesions on high b value DWI were demonstrated in following diseases: acute ischmia, hematoma, abcesses, mengioma, mutiple sclerosis(MS) The ADC value was decreased to(5 87?1 02)(10 -4 mm 2/s in superacute cerebral ischemia, while the ADC value increased to (8 08?1 15)?10 -4 mm 2/s in active MS The CV in cerebral ischemia lesions was higher than the control group( P
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Objective To discuss the problems about needle path in the procedure of CT guided percutaneous biopsy of cervical spine, and to analyze different approaches related with different lesions. Method Seventy eight cases with cervical vertebral lesions underwent CT guided percutaneous biopsy. There were 45 males and 33 females, and the age ranged from 2 to 73 years. The lesions located in C1～7 involving all parts of cervical spine. Precise needle paths were designed according to different locations of lesions. Results Seventy one of 78 cases have definite histological diagnosis, and the accuracy of biopsy was 91%. The detailed approach pathways were as follows: the pathway between vertebral artery and carotid sheath; the pathway between carotid sheath and trachea; the pathway posterior to the vertebral artery and carotid sheath. Conclusion The main principles of needle paths are as follows: the pathway should be parallel to spinal cord so as to avoid injuring the cord; avoid large vessels and important structures and pass through the interspace of them.
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Objective To summarize the appearances of MS lesions on DWI, and to quantitatively study the ADC and AI values in different clinical MS subgroups Methods One hundred and eighty seven lesions were studied in 18 cases of MS at different clinical stages Routine MR and DWI were performed in all cases ADC and AI were calculated in the lesions,NAWM, and normal control group Results Hyperintensity (edema like on T 2WI) was demonstrated on DWI at acute primary progressive MS lesions Hyperintense ring sign was found at acute relapse MS lesions ADC increased in all subgroups of MS Significant difference of ADC was demonstrated among MS lesions, NAWM, and normal control groups Significant decrease of AI was demonstrated at later stages Hyperintensity was found in all MS lesions on T 2WI The hyperintensity lesions on DWI had enhanced or non enhanced appearances on CE T 1WI The ADC value of enhanced MS lesions was less than that of the non enhanced lesions ( t =4 19, P 0 05) Conclusion DWI could give quantitative information for different pathological changes in MS lesions of different clinical subgroups Quantitative measurement of diffusion has great potential value in the diagnosis, differential diagnosis, and the prediction of prognosis in MS
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Objective To investigate the MR postprocessing workstation on PC level.To discuss the hardware enviroment suitble for the lab MR postprocessing and the correspongding clinical diagnostic value. Methods MR diffuison-weighted imaging and routine MRI were performed in 6 normal adults.The ADC and AI parameter images were rebuilt by using Perfect-Tech (version 2.0) software on the market saled PC computer. Results The process and analysis could be performed sucessfully on the the market saled PC computer. On the ADCav images,the boundary between the grey matter(GM)and white matter(WM) was blurring and showed the similar intensity.The anistropy in white matter was averaged out on the ADCav images.The ADC value was (7.59?1.12)?10 -4 mm 2/s in WM and (10.50?4.34)?10 -4 mm 2/s in GM. On the AI images,there was sharp boundary between GM and WM,with hypointensity in GM and hyperintensity in WM. The anistropy contrast was enhanced on AI images. AI was 0.20?0.09 in WM and 0.09?0.07 in GM with statistically significant difference between them(t=4.13,P
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Objective To evaluate the diagnostic value of MR arthrography for rotator cuff tear. Methods A prospective study was undertaken in 32 patients with shoulder diseases using MR arthrography. Abnormalities revealed on MR arthrography of the rotator cuff, the labrum, and the tendon of the long head of the biceps brachii muscle were recorded. The results of MR arthrography were compared with those of arthroscopy and surgery. Results Based on the results of arthroscopy and surgery, 32 patients comprised 14 complete rotator cuff tear, 6 partial rotator cuff tear, and 12 subjects without tear. For detecting rotator cuff tear, the sensitivity, specificity, and accuracy of MR arthrography were 100%, 100%, 100% respectively. For detecting complete rotator cuff tear, the sensitivity, specificity, and accuracy of MR arthrography were 100%, 94%, 97% respectively. Meanwhile, MR arthrography revealed all multi tendon tear and all abnormalities of the labrum and the tendon of the long head of the biceps brachii muscle before arthroscopy. Conclusion MR arthrography is an accurate and comprehensive method for evaluating rotator cuff tear.
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Objective： To study the changes of water molecular diffusion in the ischemic region by using MR dephase technique and discuss the potential mechanism of the diffusion changes at early stage. Methods: Totally 43 cases were studied retrospectively. There were 10 cases whose MRI examinations were performed within 6 hours，12 cases from 7－24 hours，7 cases from 2－7 days, 8 cases from 8－14 days, 6 cases from 15 days to 2 months. The apparent diffusion coefficients in the ischemic region were calculated. Results: The ADCav in the grey matter was 8.61×10－4mm2*s－1. The ADCav decreased to (4.72×10－4±1.51×10－4) mm2*s－1 in ischemic region at superacute stage, ADCav ratio to contralateral corresponding region was 0.55±0.18, and ADCav increased to (5.68×10－4±1.22×10－4) mm2*s－1 during the time range of 2-7 days, （9.22×10－4±2.07×10－4） during the time range of 8－14 days, and approaching （26.42×10－4+9.65×10－4） mm2*s－1 during the time range of 2 months. The pearson product- moment correlation between the changes of diffusion value and time was sighificent (r=0.95, P<0.001). ADCv increased at superacute stage and decreased over time. Conclusion: The diffusion of water molecules in ischemic region decreased at superacute stage, and the ADC increased over time. The anisotropy increased at superacute stage and decreased as the course developed. DWI could detect ischemic lesion much earlier than CT and routine MR examination. DWI has great value in the diagnosis of superacute stroke. The mechanism of the diffusion changes at early stage may be the intracellular toxicity edema.
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Objective To investigate the correlation between degree of deeper infiltration of NPC on CT scan,prognosis and expression of P53 protein,in order to further recognize bilogical features of NPC.Methods Collect 70 NPC biopsy specimens,which had performed CT scan before radiotherapy and had detailed clinical records.The expression of P53 protein was examined by means of S-P immunohistochemical technique.The correlation between expression of P53 protein and peripheral deeper infiltration and prognosis was analysed in detailed.Results The results of these cases showed that the positive rate of over expression P53 were 68.57%,which had no relation with the histological types and pathological grades.The positive rate of P53 in Ⅱ、Ⅲ types had a higher positive rate than that of the Ⅰ type of NPC.Expression of P53 protein had no relation with neck lymph node metastasis,but had significant correlation with the size of metastatic lymph node,which is the positive rate of P53 in diameter of metastatic lymph node ＜4 cm was higher than that of diameter ≥4 cm.Expression of P53 had no relation with local recurrence and distant metastasis after radiotherapy.Conclusion With the tumor infiltrating the deeper layer of nasopharynx,the positive rate of P53 expression is more and more high,and degree of malignant is increasing.The three types on CT scan represents the biological features of NPC.
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Objective To evaluate the functional alternations of canine renal ischemia and reperfusion injury by using MR perfusion-weighted imaging, and to correlate the imaging with the pathologic findings. Methods Using 1. 5 T MR system, four groups of three anesthetized dogs each were studied by left renal artery ligation for 30-, 60-, 90-, and 120-min, respectively, after the removal of ligation, reperfusion injury was suffered for one hour. True-FISP, TSE, and EPI sequences were performed in five different time phases ( pre-ischemia, onset-ischemia, post-ischemia, onset-reperfusion, and post-reperfusion). Finally, IR-turbo-FLASH sequence (TR 5. 8 ms, TE 3. 2 ms, TI 400 ms, FA 12?) with a temporal resolution of 1. 16 s was performed. Signal intensity (SI) in cortex, outer medulla, and inner medulla was measured. SI was plotted as a function of time. Peak height (P) , time to peak (Tp) , and the area (A) under the time-course curves after the intravenous injection of Gd-DTPA were estimated. Blood and urine examples were collected for measuring serum creatinine level and urinary protein before and after the insult. Histologic examination was performed with light and electron microscopy in all dogs. Results After arterial ligation,there was marked and significant reduction in the SI of each layer of left kidney on true-FISP, TSE, and EPI, except for the SI of inner medulla on TSE. After the removal of ligation,there were no significant differences in the SI of cortex of both kidneys, however, significant differences in the SI of outer and inner medulla of both kidneys remained on EPI in all groups. The turbo-FLASH study clearly depicted the three-phase pattern of SI changes in each layer on right kidney. The uniphasic enhancement pattern in all groups was showed in outer and inner medulla on left kidney, with the area under the curve decreased. Conclusion This preliminary study shows that MR perfusion-weighted imaging may be useful and very promising for the evaluation of renal dysfunction following normothermic ischemia and reperfusion injury.
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20, or the grade of difference is 1 or above), while no difference of bilateral enhancement was found in 1 case. Abnormal enhancement of ganglion geniculi (4/4) and labyrinthine segment (3/4) was relatively frequent, abnormal enhancement of distal part of internal auditory segment, tympanic segment, and mastoid segment was seen in 2 cases, respectively.Conclusion MRI doesn't have diagnostic value unless the enhancement of segments of the affected facial nerve side is more evident than the unaffected side for unilateral cases. Labyrinthine segment and ganglion geniculi are more susceptible to Ramsay Hunt syndrome. Gd-DTPA enhanced MRI can demonstrate segmental lesions of facial nerves objectively, thus it can be helpful in the diagnosis and differential diagnosis of Ramsay Hunt syndrome. The relationship between MRI findings and clinical representation still needs further study.
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Objective Calcium overload has important effect on cell injury in the ischemic stroke MR DWI/PWI mismatch may display the ischemic penumbra We try to explain the relationship between the characters of MR DWI/PWI and intracellular Ca 2+ in the different ischemic region through the model of focal cerebral ischemia Methods Twenty-eight rabbits underwent permanent middle cerebral artery occlusion (MCAo) From 0 5 h to 36 h after the onset of occlusion, diffusion-, perfusion-, and T 2-weighted MR imaging were performed to generate ADC, CBF, CBV parameters and anatomic images After the MR scanning, the same brain slices were incubated with Fluo-3/AM followed by the examination using laser confocal scanning microscope (LCSM) At different ischemic time, fluorescence intensity (FI) of the intracellular Ca 2+ in the DWI/PWI match region and mismatch one was recorded FI match /FI contralateral and FI mismatch /FI contralateral were produced and analyzed Results (1) MR outcome: The DWI/PWI match was located in the lateral caudoputamen and the DWI/PWI mismatch was mainly located in the frontoparietal cortex At 0 5 h after MCAo, CBF and CBV of lateral caudoputamen and frontoparietal cortex in the affected side deceased marked and the rCBF and rCBV of lateral caudoputamen were less then that of frontoparietal cortex in all groups ( t =-11 74, P
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Objective To determine the val ue of five MR imaging signs in diagnosing the bucket handle tears (BHT) of menisci of the knee. Methods MR imaging of 139 knees with subsequent arthroscope exams were retrospectively evaluated. Based on the results of arthroscopy, 19 knees had BHT of menisci. Two radiologists evaluated each MR exam independently, with discrepancies resolved by consensus. Each MR exam was analyzed for five signs: a double posterior cruciate ligament sign, a flipped meniscus sign, an absent bow tie sign, an internal displaced fragment sign, and an abnormal circumferential meniscus sign. Sensitivity, specificity, positive and negative predictive values, and accuracy for diagnosing BHT of menisci were calculated for the presence of each individual sign. Results The sensitivities of these five signs ranged between 52.6% and 89.5%, and specificities ranged between 83.3% and 98.3%, respectively. Positive and negative predictive values ranged between 42.9% and 88.2%, and between 92 7% and 98.3%, respectively. The accuracy of these five signs ranged between 82.7% and 96 4%. Conclusion BHT of menisci may have many signs on MR imaging. The diagnostic sensitivities of the internal displaced fragment sign and the abnormal circumferential meniscus sign are the highest. The double posterior cruciate ligament sign has the highest specificity and positive predictive value, while the internal displaced fragment sign has the highest negative predictive value and accuracy.
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Objective To study the diagnostic value of difusion weighted imaging in brain ischemic stroke and to summarize the MR appearances and characteristics of the false negative and false positive cases.Methods 225 cases which were highly suspected of brain ischemic stroke were studied prospectively.The final diagnosis of the cases were verified by following up examination or pathology.The diagnostic value were calculated.Results The sensitivity and specificity for the diagnosis of ischemic stroke were 93.55% and 100% at superacute stage(
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Objective To evaluate the effects of percutaneous long sheath aspiration embolectomy for the treament of acute superior mesenteric artery embolism. Methods 7 cases (atrial fibrillation 4 cases; left atrium myxoma 2 cases and chronic mesenteric ischemia 1 cases) of acute measenteric artery embolism were treated with percutaneous emlolectomy using long sheath (Optimed, Germany) aspiration. Results Successful recanalizations were observed in all of the 7 cases of superior mesenteric arteries. 5 cases out of the 7 cases recovery; 1 case underwent laparotomy; 1 case died in 24 hours. Conclusions Percutaneous embolectomy using long sheath aspiration is a sample and effective method for the treatment of acute superior mesenteric artery embolism.
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0.05).Conclusion Significant corpus callosum atrophy can be detected in both AD and VD patients, indicating that interhemispheric cortico cortical disconnections may contribute to AD and VD
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Objective To study the metabolic alteration in the brain of patients with cyanosed congenital heart disease (CCHD) by using 1H magnetic resonance spectroscopy ( 1H MRS) and discover the pathophysiology of chronic hypoxic brain, which will help to diagnose and treat this disease completely. Methods Twenty five patients with CCHD and 25 controls were performed PRESS 1H MRS and MRI, The areas under the resonance of metabolites were measured, the ratios of the other metabolites to Cr were calculated and compared. Results In patients with CCHD, the mean value of NAA/ Cr was significantly lower than that in controls ( P 0.05). Conclusion 1H MRS can detect brain metabolic changes in patients with cyanosed congenital heart disease in vivo noninvasively and can detect the metabolism disorder of the energy and amino acid, so the pathophysiology of this disease can be understood.
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Objective To compare the diagnostic value of conventional MRI, X ray arthrography, and MRI arthrography in revealing rotator cuff injuries. Methods Thirty two patients with suspected rotator cuff tears were prospectively examined by conventional MRI, X ray arthrography, and MRI arthrography before the examination of shoulder arthroscope. Based on the results of the arthroscopy, the diagnostic sensitivity, specificity and accuracy of those three different methods were determined for rotator cuff tears. Results The arthroscopic findings included 14 full thickness tears, 6 partial thickness tears, and 12 without tears. For the diagnosis of rotator cuff tears,the sensitivity,specificity and accuracy were 80%(16/20), 83%(10/12), and 81%(26/32) for conventional MRI,respectively; the figures were 80%(16/20),100%(12/12), and 86%(28/32)for X ray arthrography,respectively; while the data were 100%(20/20),100%(12/12), 100%(32/32) for MRI arthrography,respectively. For the diagnosis of complete tears, the sensitivity, specificity and accuracy were 79%(11/14), 83%(15/18), and 81%(26/32) for conventional MRI, respectively; the figures were 93%(13/14),94%(17/18), and 94%(30/32) for X ray arthrography, respectively; while the parameters were 100%(14/14),94%(17/18), 97%(31/32) for MRI arthrography, respectively. Conclusion MRI arthrography is one of the best methods for the diagnoses of rotator cuff tears.
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Objective To determine the diagnostic value of indirect MRI arthrography for meniscal tears.Methods 75 cases of routine MRI of the knee and 64 cases of indirect MRI arthrography of the knee were retrospectively reviewed.These patients all had subsequently arthroscopic examination.Based on the results of arthroscopic examination,the diagnostic value for meniscal tear of routine MRI and indirect MRI arthrography were compared.Results For medial meniscal tears,the indirect MRI arthrography gave a sensitivity of 72%,specificity of 100%,accuracy of 89.1%,positive predictive value of 100% and negative predictive value of 84.8%.For lateral meniscal tears,the indirect MRI arthrography gave a sensitivity of 83.8%,specificity of 90.9%,accuracy of 87.5%,positive predictive value of 89.6% and negative predictive value of 85.7%.No matter for medical meniscal tears or lateral meniscal tears,the diagnostic differences between the indirect MRI arthrography and the routine MRI were not statistical significant.Conclusion Although the diagnostic value of indirect MRI arthrography for meniscal tears was quite high,it was not different with routine MRI statistically.