The Clinical Value Of320-detector CT Angiography In The Diagnosis Of Aortic Dissection And Short Term Effect Treated By TEVAR

partⅠ： The clinical value of320-detector CT angiography in the diagnosisof aortic dissectionObjective To evaluate the clinical value of320-detector CT angiography(320CTA) in confirming the primary tears of aortic dissection (AD),meanwhile tocompare its image quality and dose of radiation with16-detector CTangiography(16CTA).Methods(1) From January2008to December2011,71patients who have been diagnosed asaortic dissection were enrolled in this study in our hospital,male57and female14.Age from29ys to86ys,average age (57.4±9.1)ys.Among these patients,63patients were hypertension,17patients were levelⅠ(BP141－159mmHg),27patientswere level Ⅱ (BP160－179mmHg),19patients were level Ⅲ (BP>180mmHg);8patients suffered diabetes mellitus;4patients were renal insufficiency;55patientscomplain thoracic tearing pain,4patients complain drastic abdominal pain,9patientscomplain drastic thoracic-abdominal pain and other3patients were not uncomfortableobviously.(2)28patients were examined by Toshiba Aquilion ONE320-detector CT,supineposition,foot first in.The scan range was from thoracic entrance to pubic symphysis with5mm of each slice.we preset a descending aorta section which parallels to T8asour ROI. as long as the CT value of ROI greater than100HU,the scan procedure willbe triggered automaticly.43patients were examined by Siemens Somatom16-detectorCT,supine position,head first in.The scan range was from thoracic entrance to pubicsymphysis with10mm of each slice.According to our experience,the scan procedurewas launched28seconds after the beginning of the injection of contrast agent.Both ofthe two groups pick Ultravist as (300mgI/ml)contrast agent.The rate of injection was3.5ml/s,the total dosage of contrast agent was determined by the patients’ weight,eachkg of the weight equal to1.5ml contrast agent.(3) We considered the position of primary tears which confirm by DSA aorticangiography as our "gold standard",if the position of primary tears diagnosed by CTAdeviated "gold standard" less than5mm,which had no negative influence for thepatients’ operation blueprint,we considered the diagnosis was accuracy.Otherwise thediagnosis was considered as inaccuracy.(4) We picked up10cases randomly from group of320-detector CTA and16-detector CTA respectively.Then asked five observers to evaluate the quality ofthese images.Including density resolution,contrast of enhanced scan image,gray scaleclarity,matrix and detail of image and the ability to reduce motion artifact. The scoreswere marked as descending order by4,3,2,1according to the quality of theseimages.Finally,we calculated the total score of each group for further analysis.(5) According to the Patient Protocol,we recorded the dosage of radiation of28patients examined by320-detector CTA and16-detector CTA.Results(1) Totally71patients were diagnosed as aortic dissection,19patients were typeDebakeyⅠ,4patients were type DebakeyⅡ,48patients were type DebakeyⅢ,which11patients were type DebakeyⅢa and37patients were type DebakeyⅢb.Among the28patients examined by320-detector CTA,17patients were treated byTEVAR.Meanwhile15patients accepted TEVAR who were also examined by16-detector CTA.All above the patients treated by TEVAR were type Debakey Ⅲ.Before the operation,aortic angiography were processed to confirm the position ofprimary tears.The diagnostic accuracy rate for preoperative revealing of the tears of320-detector CTA (94.11％)was the same as16-detector CTA(86.67％，χ2＝0.52P>0.05).(2) There was no statistically significant difference of average score between320-detector CTA group (18.42±1.25) and16-detector CTA group (18.34±1.39,t=0.31，P>0.05).(3) The radiation dosage of320-detector CTA group (875.2±116.4mGy) was lowerthan that of16-detector CTA group (970.8±98.8mGy，t=3.71，P<0.05).For patientswhose BMI less than24(BMI<24),the radiation dosage of320-detector CTA group(768.1±33.5mGy) was lower than that of16-detector CTA group (867.6±19.8mGy，t=8.26，P<0.05).For patients whose BMI was between24and28(24<BMI<28),theradiation dosage of320-detector CTA group (879.5±44.6mGy) was lower than thatof16-detector CTA group (968.9±27.2mGy，t=7.90，P<0.05).For patients whoseBMI more than24(BMI>24),there was no statistically significant difference between320-detector CTA group(1099.4±89.7mGy) and16-detector CTA group(1140.2±94.9mGy，t=0.70，P>0.05).ConclusionBoth320-detector CT angiography and16-detector CT angiography are secure,quick, effective and nontraumatic examination in diagosing aortic dissection.They areable to display the intimal flap, the real and fake lumen, the thrombus in fake lumenand detail of significant branches of aorta.Both of the two kinds of imagingexamination have high diagnostic accuracy in confirming the position of primary tearsof aortic dissection.Without losing the quality of image,320-detector CT angiographycan reduce the radiation dosage effectively,especially for patients whose BMI are lessthan28.Meanwhile the motion artifact of320-detector CT angiography is lighter than16-detector CT angiography.So320-detector CT angiography possess importantclinical value in drawing up the surgical plan of aortic dissection. partⅡ: The short term effect of type DebakeyⅢ aortic dissection treated byTEVARObjective To evaluate the short term clinic effect of type DebakeyⅢ aorticdissection treated by thoracic endovascular aneurysm repair (TEVAR).Methods(1) From June2010to September2011,13patients who have been diagnosed asaortic dissection and accepted TEVAR in our hospital were enrolled in thisstudy,male10and female3.Age from34ys to85ys,average age (55.6±8.3)ys.Among these patients,11patients were hypertension,2patients were levelⅠ(BP141－159mmHg),3patients were levelⅡ(BP160－179mmHg),6patients were levelⅢ(BP>180mmHg).9patients were acute onset dissection.8patients complain thoracictearing pain,1patient complain drastic abdominal pain.4patients were chronic caseswho complain chest tightness,eventually diagnosed by CT angiography.(2) Firstly,informed patients’ family the condition and elaborated operation plan aswell as complication,make sure operation agreement was signed.Then completepreoperative examination.Controlling blood pressure, ECG monitoring,trachealintubation and general anesthesia.The surgery was monitored by Siemens Axiom ArtisDSA. We sterilized left arm regularly,punctured left brachial artery with5F punctureneedle by Seldinger’s technique;c.urveyed5F pig tail catheter to the origin ofascending aorta.In order to confirm the exact position, scale,shape and vicinityanatomy of primary tear,we injected contrast agent by high pressure syringe forangiography.Injection rate was15ml/s,total amount was30ml,measured the diameterof inner aorta so as to choose proper graft stent for transplantation.Then,we sterilizedthe underbelly and the perineum, dissociated right femoral artery and blocked thebloodstream so as to puncture it.Curveyed catheter over the primary tear,ensured thecatheter was in real lumen,withdrawed the catheter and conserve the guidewire.Transported the stent to anchor point guided by guide wire.did anotherangiography to make sure that the stent could cover the primary tear completely.Released the stent quickly monitored by fluoroscopy and withdrawed theconveyer.Finally,closed the incision and sent the patient to ICU for further treatment.(3) To monitor the patients’ signs of life intensively after the surgery.Two weekslater we run a CTA scan to observe the position of the stent,the thrombus in fakelumen and the complications. We followed up all these patients1month,3months,6months,9months and12months after surgery respectively and recorded the livingcondition of these patients.ResultsAll operations of these patients were completed successfully.One of them diedtwo weeks after the surgery because of cerebral infarction,the rest of them weredischarged smoothly.One case survived7months,another one survived11months.Thesuccess rate of TEVAR was100%,the survival rate of1month,3months and6monthswas92.3%,the survival rate of9months was82.0%,the survival rate of12monthswas70.3%.Two cases which was acute onset dissection suffered type Ⅰcomplication,which was also called internal leakage of proximal end,treated byconservative treatment.Eventually they were self healed.In the reexamination twoweeks after operation by CTA,thrombus in fake lumen could be observed and therewas no complication with the rest of7acute cases and4chronic cases.