Comparison Study Of CTA And 2D-DSA In Diagnosis And Treatment Of Intracranial Aneurysms

Intracranial aneurysms with acute subarachnoid hemorrhage (SAH) is a verydangerous disease. Its mortality and mutilation rate is considerable high.Therefore, fast and accurate diagnosis and early treatment is of great importancein lowering mortality and improving the prognosis of patients. It has become themost general public health problem in the world. At present, imaging diagnosis isstill used as the standard method in diagnosis of cerebral aneurysms. The purposeof examination is to explore the presence or not of (an) aneurysm(s), identify thestem and origin of aneurysm and its spatial relationship and direct the surgicaltreatment. Especially, the problem of the depiction and measurement of aneurysmneck has aroused more and more attention of neurosurgeons. Clear display andaccurate measurement of aneurysmal morphological features and aneurysm neck,exact evaluation of relationship between the aneurysm and surrounding structuresare so important and according this, the neurosurgeons will decide whethersurgical or endovascular interventional treatment will be performed. In recentyears, there are numerous reports about imaging detection method and expect toexplore an excellent technique used in the diagnosis of intracranial aneurysms. The purpose of this study was to compare the advantages and disadvantagesof CT angiography (CTA) and digital subtraction angiography (DSA) in thedetection, measurement and clinical usefulness of intracranial aneurysms in orderto do some contributions to early and accurate diagnosis and treatment ofaneurysms, reduce fatality and improve prognosis of patients. A total of 335 patients were admitted to our hospital under clinical symptomsand signs suggestive of harboring an intracranial aneurysm between October 2003and October 2005, 134 men and 201 women, ranging in age from 18 to 73 years,and the average age was 47.4 years. Among them, 209 patients were detected byCTA, DSA was performed in 59 patients, 67 patients underwent CTA and DSAcombined examination. All CTA examinations were performed with spiral CTmachine (Hi-Speed Scanner, General Electric Medical System). DSA detectionswere performed with Angiostar angiography system (Siemens, Germany). Clinicaldiagnosis was made after CTA or/and DSA detection. According to theinformations depicted by CTA or/and DSA, such as aneurysmal shape, size,location, orientation, neck and its relation to parent artery and surrounding bonystructures, appropriate surgical and interventional project would be made. Except66 patients who didn't accept any surgical treatment, surgical or/and endovasculartreatment were performed in 269 patients. We compared CTA and DSA findingswith the microsurgery or endovascular interventional treatment results, analyzedthe sensitivity, specificity, accuracy, three dimensional imaging capabilities andspatial resolution of CTA and DSA method, and evaluated the clinical usefulnessof two methods for endovascular interventional treatment or microsurgery,choosing operation time, preoperative analysis and postoperative recheck. Weevaluated the advantage and disadvantage of two methods in all factors. Using χ2test and SPSS 13.0 statistical software, it has the statistical significance whenp<0.05.We also follow up the patients whose results are negative from threemonths to half year.The results show that among 67 cases in CTA+DSA combined group, CTAdetected 53 positive cases, which hold 79.1%, and 69 aneurysms. While DSAdetected 52 positive cases, which hold 77.6%, and 68 aneurysms. We confirmed53 positive cases and 69 aneurysms through microsurgery and endovascularinterventional treatment. Compared CTA and DSA diagnosis results with the finaldiagnosis results, we found that CTA detected 52 true positive cases and 68aneurysms, 1 false positive cases and 1 false negative cases, and the sensitivity,specificity and the accuracy rating were 98.1%, 95.9% and 98.6% respectively.While DSA detected 51 true positive cases and 67 aneurysms, 1 false positivecases and 2 false negative cases, the same three rates of DSA were 96.2%, 92.9%and 97.1%. CTA had the same specificity as DSA, while a little higher insensitivity and accuracy than DSA. But we found no significant differencebetween CTA and DSA in aneurysm detection rate through χ2 test.In CTA+DSA combined group, CTA display the neck and the body of theaneurysms exactly and show the spatial relations between the aneurysm and itsparent artery and surrounding bony structures in the best suitable directionthrough selecting various angles to observe in 54 aneurysms. It can also measurethe neck and the body of the aneurysm and offer the ratio, which hold 78.3% intotal. While DSA can display the three dimensions appearance and spatialstructure clearly in 40 aneurysms, holding 58.8%, which is lower than CTAobviously.There are 69 definite aneurysms in CTA+DSA combined group. CTAprovides fairly valuable information in selecting clinical treatment plan (clipping,wrapping or interventional therapy) in 58 aneurysms, which hold 84.1%.16aneurysms (23.2%) among the total were selected to take microsurgery owing tothe factors of the form of the vessel or the thrombus on the tunica intima. While42 aneurysms (60.9%) were selected to take interventional therapy because CTAoffer fairly valuable information, such as the ratio between the neck and the bodyof the aneurysm. CTA shows no significant difference to DSA in 11 aneurysm(15.9%).Among 167 operation cases in CTA group, 37 cases took surgery therapy in72h after invasion, which hold 22.2% (37/167). While there are only 3 casesamong 48 operation cases in DSA group, which hold 6.3% (3/48).Among 269 operation cases, 23 patients come to our hospital to rechecknearly 1 year after operation. 18 cases had been taken for microsurgery. After CTAcheck, we find that the body of the aneurysm is completely obstructed and noremain of the neck of the aneurysm and the aneurysm clip is in its good positionin 17 cases. We find a new middle cerebral artery aneurysm near the aneurysmclip. 5 cases had been cured for GDC embolotherapy. After DSA check, we findthat the body of the aneurysm is completely embolized in all cases and no remainof the neck of the aneurysms.From above-mentioned investigation, we can draw such conclusions1. CTA shows no significant difference to 2D-DSA in aneurysm detectionrate.2. CTA is significantly advantageous over DSA in displaying the threedimensions appearance and spatial structure of the aneurysm.3. CTA is advantageous over DSA in early diagnosis and treatment ofaneurysm. It provides fairly valuable information in selecting treatment andformulating treatment plan of microsurgery or interventional therapy.4. 2D-DSA can offer the hemodynamic information of the cerebral vesselsand it is the basis of interventional treatment of intracranial aneurysms, which ishardly replaceable.5. CTA can be the available method of post-operative evaluation andrecheck of aneurysm.