Measurements before endovascular repair of abdominal aortic aneurysms. MR imaging with MRA vs. angiography and CT

Purpose:
1) To compare measurements obtained with MR imaging (MRI)/contrast-enhanced MR angiography (CE MRA) with measurements obtained with angiography (DSA) and CT, for stent-graft sizing of abdominal aortic aneurysms (AAA). 2) To compare MRA measurements obtained with the two post processing techniques MIP (maximum intensity projection) and VRT (3D volume rendering technique). Material and Methods:
The prospective study included 20 consecutive patients with AAA identified by DSA and CT as suitable for endovascular repair. For the study, MRI/CE MRA was performed. Five measurement variables for stent-graft sizing were chosen. Comparisons were made between MRI/CE MRA, DSA and CT, and between observers. Comparisons were also made between MIP and VRT. Results:
Significantly shorter lengths were obtained with MRA-MIP than with DSA. Three out of six diameter measurements were significantly smaller on MRI/CE MRA than on DSA and CT. No significant differences were found between the observers. One diameter measurement was significantly smaller on MIP than on VRT, while the other measurements showed no significant differences. Conclusion:
The length measurements obtained with MRA-MIP were probably more correct than those with DSA. For more reliable diameter measurements with CE MRA, improvements of the technique, including VRT reconstructions and a standardized determination of the vessel boundaries, are needed.     

The non-invasive detection of intracranial aneurysms: are neuroradiologists any better than other observers?

Can non-neuroradiologists detect intracranial aneurysms as well as neuroradiologists, using CT and MR angiography? Sixty patients undergoing intra-arterial digital subtraction angiography (IADSA) to detect aneurysms also underwent computed tomographic angiography (CTA) and time-of-flight magnetic resonance angiography (MRA). Consensus review of IADSA by two neuroradiologists was the reference standard. Two neuroradiologists, a neurosurgeon, a neuroradiographer and a general radiologist blinded to IADSA, plain CT and clinical data, independently reviewed hard-copy base and reconstructed maximum intensity projection images of the CTA and MRA studies. Thirty patients had a total of 63 aneurysms, 71.4% were 相似文献   

Thoracic aortic stent graft: comparison of contrast-enhanced MR angiography and CT angiography in the follow-up: initial results

The objective of this study was to compare contrast-enhanced magnetic resonance angiography (CE MRA) and multislice computed tomographic angiography (MS CTA) in the follow-up of thoracic stent-graft placement. The CE MRA and MS CTA were performed following nitinol stent-graft treatment due to thoracic aneurysm (n=4), intramural bleeding (n=2) and type-B aortic dissection (n=5). Corresponding evaluation of arterial-phase imaging characteristics focused on the stent-graft morphology and leakage assessment. Stent-graft and aneurysm extensions were comparable between both techniques. Complete exclusion (aneurysm, n=4; dissection, n=2) was assessed with high confidence with CE MRA and MS CTA. Incomplete exclusion (intramural bleeding, n=2; dissection, n=3) was assigned to lower confidence scores on CE MRA compared with MS CTA. On CE MRA the stent-graft lumen demonstrated an inhomogeneous signal, the stent struts could not be assessed. The CE MRA can be used as alternative non-invasive imaging for follow-up of nitinol stent grafts. Arterial-phase leak assessment can be less evident in CE MRA compared with MS CTA studies; therefore, the use of late-phase imaging seems to be necessary. The diagnostic gap of stent-graft fracture evaluation using MRA may be filled with plain radiographs.     

Vascular lesions of the renal sinus

The renal sinus contains within it the collecting system of the kidney as well as lymphatics, nerves, and renovascular structures. This area may be affected by a large variety of pathological conditions arising from the various tissues in this site. Vascular lesions of the renal sinus are uncommon and may present clinically with acute symptoms and on imaging as a mass lesion. Awareness of the different vascular lesions affecting this area is essential for establishing the correct diagnosis and for appropriate treatment. The role of computed tomography is emphasized because it is the most commonly used modality to evaluate acute abdominal conditions as well as suspected renal masses, and the diagnosis can usually be made without the need for additional imaging modalities.All departments affiliated to the Sackler School of Medicine, Tel Aviv University, Israel     

Risk factors for the occurrence of chronic subdural haematomas after neurosurgical procedures

Summary ¶Chronic subdural haematoma (CSDH) is a rare clinical complication of neurosurgical procedures. CSDH occurs sporadically after aneurysm clipping surgery and revascularisation surgery but the risk factors are not known. The present study reviewed 6613 consecutive neurosurgical procedures performed from January 1987 to July 2001, and identified 621 cases of CSDH. Fifty of these 621 cases had a past history of neurological disorders treated by neurosurgery. This study evaluated these 50 cases in order to elucidate the clinical and radiological characteristics of CSDH after neurosurgery and to investigate the etiology for identifying in the risk factors of CSDH as a postoperative complication. The incidence of CSDH after neurosurgery was 0.8% (50/6613). Twenty-seven of the 50 patients with a past history of neurosurgery had undergone aneurysm clipping surgery. The incidence after clipping surgery was 2.4%. Twelve of these 27 cases also underwent ventriculoperitoneal shunting. Three patients had postoperative CSDH after arachnoid cyst opening and/or shunting. The incidence was highest at 7.5%. Three patients had postoperative CSDH after brain tumour surgery. The incidence was low at 0.4%. However, the ventricular cerebrospinal fluid (CSF) space was opened during tumour removal in 2 of these 3 patients.Communication of the subarachnoid space to the subdural space is considered to be one of the causative factors and excessive CSF shunting facilitates formation of CSDH after neurological surgery. Repair of arachnoid tearing during neurosurgery and avoidance of excessive CSF shunting may reduce the risk of CSDH after neurosurgery.Published online May 19, 2003     

A clinical comparison of non-traumatic acute subdural haematomas either related to coagulopathy or of arterial origin without coagulopathy

Summary ¶Background. Non-traumatic acute subdural haematomas enable study of the morbidity and mortality due to the haematoma without the effect of trauma. Whereas it is known that coagulation disorders worsen the outcome of spontaneous intracerebral haematomas, this has not been studied in non-traumatic acute subdural haematomas. Methods. In a series of 13 non-traumatic acute subdural haematomas admitted to our department between January 1995 and March 2002, we had 9 coagulopathy associated haematomas and 3 haematomas corresponding to the syndrome of spontaneous acute subdural haematoma of arterial origin. Both groups were compared. Findings. Age and gender distribution were comparable. The bleeding source was a cortical artery in 2 of the 2 non-coagulopathy related haematomas operated on, but also in 2 of the 4 coagulopathy associated haematomas that underwent surgery. The average haematoma thickness was higher in the coagulopathy related haematomas. The mean Glasgow Coma Score on admission was 7,7 and the mortality rate was 55,6% in the coagulopathy related group. In the non-coagulopathy related haematomas the mean Glasgow Coma Score was 12,0 and the mortality rate 33,3%. The latter mortality rate corresponds well to that of a historical group of spontaneous acute subdural haematomas of arterial origin collected from the literature. Interpretation. The outcome was worse in the non-traumatic acute subdural haematomas that were associated with a coagulation deficiency. While in all non-traumatic acute subdural haematomas the interval to surgery should be minimized, early recognition and urgent correction of coagulation deficiencies is certainly indicated.Published online May 19, 2003     

Development and rupture of a <Emphasis Type="Italic">de novo</Emphasis> basilar artery aneurysm after surgical removal of a cerebellar arteriovenous malformation

Summary ¶Background. The de novo development of an aneurysm in an previously normal artery is an uncommom event. We describe a patient who developed a de novo bleeding aneurysm of the basilar artery in the three weeks following the surgical removal of a large cerebellar AVM. Method-findings. A 48-year-old man suddenly developed transient headache, vertigo and disturbance of balance. Neuroradiological examinations showed the presence of a large AVM of the right cerebellar hemisphere. The AVM was removed successfully; following the operation there were repeated bleeding episodes at the operating site, requiring surgical evacuation. Three weeks after the AVM removal he suffered from a massive subarachnoid haemorrhage due to the rupture of an aneurysm developed de novo in the basilar artery. Interpretation. This is the first reported case, to our knowledge, of a de novo aneurysm developed in an artery hemodynamically related to a surgically removed AVM. This complication was probably due to the postoperative hemodynamic changes in the vessels afferent to the AVM, associated with arterial wall dysplasia.     

Induced and spontaneous abortion and breast cancer risk: results from the E3N cohort study

Recent reviews reach conflicting conclusions on breast cancer risk after spontaneous or induced abortion. E3N is a large-scale cohort study collecting detailed information on environmental and reproductive factors. We investigated the relation between breast cancer and a history of induced and/or spontaneous abortion, using the data from the 100,000 women aged 40-65 at entrance in 1990. Among them, over 2,600 new invasive breast cancers had been diagnosed by June 2000. Multivariate analysis, adjusted for known potential confounders, showed no association between a history of induced abortion and breast cancer risk either in the whole population (relative risk [RR] = 0.91, 95% confidence interval [CI] 0.82-0.99) or in subgroups defined by parity or by menopausal status. Overall, the association between spontaneous abortion and breast cancer was not significant (RR = 1.05, 95% CI 0.95-1.15). However, there is a suggestion of increased risk with increased number of miscarriages (RR = 1.20, 95% CI 0.92-1.56 after 3 or more). Moreover, an interaction with menopausal status was observed. In premenopause, the risk decreased with increasing number of spontaneous abortions, whereas it increased in postmenopause. Among nulliparous and parous women, the relative risk estimates were respectively equal to 1.16 (95% CI 1.04-1.30, p trend < 0.0008) and 1.14 (95% CI 1.01-1.28, p trend = 0.005). Premenopausal breast cancer, on the other hand, appeared to be less frequent in women who had had repeated miscarriages. We conclude that there is no relationship between breast cancer and induced abortion but that an association with spontaneous abortion is possible and may depend on menopausal status.     

Aortic Aneurysm Rupture in Infantile Marfan's Syndrome

A 3-year-old boy with early rupture of an aortic aneurysm due to infantile Marfan's syndrome is presented. In an emergency operation we prepared a composite graft using a 17-mm St. Jude prosthesis with an 18-mm vascular conduit. The postoperative period was complicated by pneumothoraces, transient bilateral phrenic nerve paralysis, cerebral convulsion, and supraventricular tachycardia. Four months postop the composite graft was replaced with an aortic homograft due to severe stenosis. His condition after 12 months is excellent.