Vertebral Tortuosity Index in Patients with Non-Connective Tissue Disorder-Related Aneurysm Disease

OBJECTIVE

The vertebral tortuosity index (VTI) predicts increased risk of acute aortic events in patients with known genetic aortopathies. This study describes the VTI in a cohort of patients with non-connective tissue disorder-related large aneurysms.

METHODS

Hospital imaging records from July 2012 to March 2016 were interrogated to identify patients with aneurysmal disease who had undergone computed tomographic angiography that included imaging of vertebral arteries. A control group of consecutive patients undergoing carotid and vertebral imaging was also assessed. VTI was calculated using the formula: [(centre-line distance) / (straight-line distance)-1] ×100 for all patients, and statistical analysis undertaken to determine whether measured VTI was statistically different in patients of younger age, with larger aneurysms, or an acute presentation. Comparison was made with patients who had no aneurysm disease.

RESULTS

Sixty-five patients were identified with adequate imaging to assess the entire aorta, including vertebral arteries. The majority of patients were male (71%, 46/65) and mean age at the time of the CT scan was 71 years (SD 11.1 years). There were 11 patients under the age of 60 years in this cohort. The mean VTI was 33.17 (SD 20.43). There was no statistically significant difference between different territories of presentation (proximal vs. distal aneurysm, p=.94), age of patient (>60 years vs. <60 years, p=.2), or size of aneurysm (>6 cm vs. <6 cm, p=.09). Acuity of presentation was not predicted by a higher VTI (p=.69). The VTI in patients with aneurysms was higher than in patients without aneurysm disease (VTI = 16.1, p<.005) CONCLUSIONS: An elevated VTI is consistently present in patients with degenerative aneurysms and has potential as a universally available predictive measurement. However, the increased VTI in the older cohort without connective tissue disease may not carry the same predictive value for acute presentations as has been demonstrated in younger patients with a known genetic basis for their aortopathy.

A Comparison of Accuracy of Image- versus Hardware-based Tracking Technologies in 3D Fusion in Aortic Endografting

OBJECTIVES

Fusion of three-dimensional (3D) computed tomography and intraoperative two-dimensional imaging in endovascular surgery relies on manual rigid co-registration of bony landmarks and tracking of hardware to provide a 3D overlay (hardware-based tracking, HWT). An alternative technique (image-based tracking, IMT) uses image recognition to register and place the fusion mask. We present preliminary experience with an agnostic fusion technology that uses IMT, with the aim of comparing the accuracy of overlay for this technology with HWT.

METHOD

Data were collected prospectively for 12 patients. All devices were deployed using both IMT and HWT fusion assistance concurrently. Postoperative analysis of both systems was performed by three blinded expert observers, from selected time-points during the procedures, using the displacement of fusion rings, the overlay of vascular markings and the true ostia of renal arteries. The Mean overlay error and the deviation from mean error was derived using image analysis software. Comparison of the mean overlay error was made between IMT and HWT. The validity of the point-picking technique was assessed.

RESULTS

IMT was successful in all of the first 12 cases, whereas technical learning curve challenges thwarted HWT in four cases. When independent operators assessed the degree of accuracy of the overlay, the median error for IMT was 3.9 mm (IQR 2.89-6.24, max 9.5) versus 8.64 mm (IQR 6.1-16.8, max 24.5) for HWT (p = .001). Variance per observer was 0.69 mm(2) and 95% limit of agreement ±1.63.

CONCLUSION

In this preliminary study, the error of magnitude of displacement from the "true anatomy" during image overlay in IMT was less than for HWT. This confirms that ongoing manual re-registration, as recommended by the manufacturer, should be performed for HWT systems to maintain accuracy. The error in position of the fusion markers for IMT was consistent, thus may be considered predictable.

Early Experience of Endovascular Repair of Post-dissection Aneurysms Involving the Thoraco-abdominal Aorta and the Arch

OBJECTIVES

Outcomes are reported in management of post-dissection aneurysms involving the aortic arch and/or thoraco-abdominal segment (TAAA) treated with fenestrated and branched (complex) endografts.

METHODS

This report includes all patients with chronic post-dissection aneurysms >55 mm in diameter, deemed unfit for open surgery, treated using complex endografts between October 2011 and March 2015. When appropriate, staged management strategies including left subclavian artery revascularization, thoracic endografting, dissection flap fenestration or tear enlargement, and other endovascular procedures were performed at least 3 weeks prior to definitive complex endovascular repair. The following outcome data were collected prospectively at discharge, 12 months and annually thereafter: technical success, endoleaks, target vessel patency, false lumen patency, aneurysm diameter, major and minor complications, re-interventions, and mortality.

RESULTS

The cohort comprised 23 patients with a median age of 65 years. Staged procedures were performed in 14 patients (61%). Seven patients with dissections involving the arch were treated with inner branched endografts, and 16 TAAA patients were treated with fenestrated or branched endografts. The technical success rate was 71% following arch repair and 100% following TAAA repair. During early follow up, one of the arch group patients died and one in the TAAA group suffered spinal cord ischemia. The median follow up was 12 months (range 3-48), during which time one patient died of causes unrelated to aneurysm or treatment. Two early re-interventions were performed in the arch group to correct access vessel complications and there were a further two late re-interventions in the TAAA group to treat endoleaks. All target vessels (n = 72) remained patent.

CONCLUSIONS

This experience indicates that complex endovascular repair of post-dissection aneurysms is a viable alternative to open repair in patients deemed unfit for open surgery. There are insufficient data to allow comparison with the outcome of open surgery in anatomically similar, but fit, patients.

Current and future perspectives in the repair of aneurysms involving the aortic arch

The repair of aneurysms involving the aortic arch is technically and physiologically demanding. Historically, these aneurysms have been treated using open surgical techniques that require cardiopulmonary bypass and deep hypothermic circulatory arrest. Many patients have been deemed "untreatable" and among those selected for surgery there are reported risks of death in 2% to 16.5% and stroke rates ranging from 2% to 18%. "Hybrid arch repair" combines one of a number of open surgical procedures (to secure a proximal landing zone for an endograft) with subsequent or immediate placement of an endograft in the arch and descending aorta. Although this concept is described as "minimally invasive" because it avoids aortic cross-clamping and hypothermic circulatory arrest, the morbidity and mortality rates remain considerable (mortality 0% to 15%, stroke 0% to 11%). Ongoing development of endograft technology has enabled total endovascular repair of complex aortic aneurysms involving the visceral segment, using fenestrated and branched endografts. Encouraging early results in this anatomy have inspired extension of the concept to include the aortic arch and great vessels. These strategies can be considered in patients generally at high-risk for the conventional procedures. However, the endeavour is at an early stage of its development and the arch poses unique challenges including the potential for stroke, angulation of the arch and the great vessel ostia to the arch, extremely high volume flow, three-dimensional pulsation and rotation with the cardiac cycle and the proximity of the aortic valve and coronary arteries.

MR imaging of arrhythmogenic right ventricular dysplasia: What the radiologist needs to know

Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is an inherited heart muscle disease that predominantly affects the right ventricle. Clinical manifestations are related to severe ventricular arrhythmia that may lead to sudden death, mostly in young patients. Magnetic resonance imaging (MRI), included in the new diagnostic criteria since 2010, aims to detect segmental and global wall motion abnormalities, reduced ejection fraction, right ventricular dilatation and right ventricular diastolic/systolic dysfunction. An MRI assessment of the right ventricle is often challenging, partly because the MRI diagnostic criteria have some limitations, and also because it requires a significant learning curve due to the low prevalence of the disease. Therefore, this article aims to review the pathophysiology of the disease, the cardiac MRI protocol, images of the various stages of this affection as well as the differential diagnosis.

Juxtarenal aortic aneurysm with hostile neck anatomy: midterm results of minilaparotomy versus f-EVAR

AIM

The aim of this study was to compare the results of complex aneurysm (hostile neck anatomies) repair in high-risk patients with two minimally invasive techniques, fenestrated endografting (f-EVAR where EVAR stands for endovascular aneurysm repair) and minilaparotomy.

METHODS

All high-risk patients (N.=50, group 1) with hostile neck abdominal aortic aneurysms (AAAs) operated in the vascular surgery department of the "Policlinico Universitario G. Martino" of Messina (Italy) during a 5-year period (January 2006-December 2010) were cross-matched with 50 similar patients (group 2) treated in the Vascular Surgery Department of the "Hopital Cardiologique" University of Lille (France) with similar anatomies, comorbidities and risk factors. The patients in group 1 underwent open minilaparotomy surgery, and the patients in group 2 were treated with f-EVAR. The aim of our study was to compare perioperative complications, survival and reintervention rates.

RESULTS

Perioperative cardiac complications occurred in 5 patients (10%) in group 1, and 1 patient (2%) in group 2 (P<0.092). Renal impairment not requiring permanent hemodialysis was significantly higher in group 1 (14% vs. 2% P<0.027), as well as respiratory complications (32% vs. 2% P<0.0001). Five patients (10%) in group 1 underwent reintervention vs. 4 patients in group 2 (P<0.7268). There was no statistically significant difference for survival rates at 30 days (92% in group 1 and 96% in group 2; P=0.399); at six months (90% vs. 96%; P=0.239); at one year (90% vs. 96%; P=0.239); and at two years (84% vs. 94%; P=0.110). However, we observed statistically significant differences in survival rates at three years (74% vs. 94%; P<0.006); at four years (70% vs. 86%; P<0.005); and at five years (65% vs. 68%; P<0.003).

CONCLUSION

Our results showed that both techniques are effective in the treatment of AAA with hostile neck in high-risk patients. Although operative mortality rate was not statistically different, f-EVAR showed better results in terms of early complications and late survival.

Chronic dissection - indications for treatment with branched and fenestrated stent-grafts

The treatment of chronic aortic dissection is a major challenge for the vascular surgeon. Close imaging follow-up after the acute episode frequently identifies dilation of untreated aortic segments. Aortic dissection often extends to both the supra-aortic trunks and to the visceral aorta. The poor medical condition that often characterizes these patients may preclude extensive open surgical repair. Recent advances in endovascular techniques provide a valid alternative to open surgery. These complex lesions can now be managed using thoracic branched and fenestrated endografts. However, clinical data are scarce and only 3 small series from 3 high-volume aortic centers are currently available. Careful anatomical study on 3D workstations is mandatory to select patients that are candidates for complex endovascular exclusion; a specific focus on the available working space within the true lumen, extension to the arch and/or the visceral/renal arteries, and false lumen perfusion of visceral vessels is required. An excellent understanding of those anatomic details demands high-quality preoperative CTA. Intraoperative advanced imaging applications are a major adjunct in the achievement of technical success.

A new score to predict post operative complications after endovascular treatment of thoraco abdominal aortic aneurysms

BACKGROUND

The endovascular treatment of thoraco abdominal aortic aneurysms (TAAA) is a minimally invasive solution. However, patient selection remains a major problem. We have analysed our experience to identify the risk factors for post-operative morbidity and mortality and to construct a scoring system to identify those patients likely to benefit from this treatment.

METHODS

We have analysed a consecutive cohort of patients treated electively for TAAA using endovascular techniques between 2006 and October 2012. All data were collected prospectively. The risk factors associated with spinal cord ischemia (SCI), the need for post-operative dialysis and 30 day mortality were determined using multivariate statistical techniques and a logistic regression model including all variables that were significant on univariate analysis (p < 0.05). A predictive score was calculated using a Received Operating Characteristic (ROC) curve, defining best specificity and sensibility.

RESULTS

We analysed the data from 123 patients (median age 70 years). The 30 day mortality rate was 8% (10 patients). The SCI rate was 6% (7 patients). One patient (1%) required long-term dialysis after the aortic procedure. The cumulative early mortality, SCI and permanent dialysis rate was 14% (17 patients). In multivariate analysis, adverse outcome was associated with advanced age (OR = 1.110 ; p = 0.022), and Crawford type I or II or III (OR = 9.292 ; p = 0.002) as compared with Crawford type IV. Pre-operative beta blocker (BB) treatment was a protective factor (OR = 0.099 ; p = 0.005). A predictive score was then constructed : Score = -10.060 + 0.104x(A) +2.229x(B) -2.315x(C) (A = patient age ; B = 1 if TAAA Crawford type 1, 2 or 3, 0 if TAAA type 4 ; C = 1 if on-going BB treatment (30 days pre-surgery minimum), 0 if none). Its sensitivity and specificity were 88% and 89% respectively.

CONCLUSIONS

We propose a simple predictive scoring system. This tool is useful in predicting the most feared complications after endovascular TAAA repair and has potential use in the identification and counselling of vulnerable patients being considered for surgery. More data are needed to refine the prediction of individual operative risks.

Techniques to reduce radiation and contrast volume during EVAR

There is a large variability observed in the literature regarding radiation exposure and contrast volume injection during endovascular aortic repair (EVAR). Reducing both in order to decrease their respective toxicities must be a priority for the endovascular therapist. Radiation dose reduction requires a strict application of the "as low as reasonably achievable" principles. Firstly, all X-ray system settings should be defaulted to low dose, and fluoroscopic time reduced as much as possible. Digital subtraction angiography runs should be replaced by recorded fluoroscopy runs when possible. Magnification should be avoided, whereas collimation should be systematic to minimize scatter radiation and focus only on the area of interest. Advanced imaging modes can also contribute to dose reduction. For instance, image fusion can facilitate endovascular navigation, and allow table and C-arm positioning without fluoroscopy. In our experience, routine use of image fusion during EVAR significantly reduces both radiation exposure and contrast volumes during complex EVAR. To make these imaging modes useable in real life settings, the X-ray system should be fully controlled by the operator from table side. Reducing iodinated contrast volume, while maintaining image quality, can also be achieved through the use of automated contrast injectors. Additionally, alternative contrast agents, like carbon dioxide (CO2) and gadolinium, have also been evaluated and can be used in specific cases. Contrast-enhanced ultrasound and intravascular ultrasonography are currently developed as potential alternatives to both iodinated contrast use and X-ray during EVAR. Lastly, specific education and training of operators in radiation protection are essential.

An optimal combination for EVAR: low profile endograft body and continuous spiral stent limbs

AIM

to evaluate the outcomes of EVAR performed with a new generation of bifurcated endografts and limbs.

METHODS

prospectively collected data from fifty consecutive patients with abdominal aortic aneurysms (AAA) treated at our institution with a Low Profile Zenith(®) bifurcated body/Zenith(®) Spiral-Z legs combo were analysed. AngioCT scans and Ultrasound exams were performed prior to discharge. Ultrasound examination was repeated 6 months after the procedure to assess endograft patency and to depict endoleaks

RESULTS

Median age was 70.6 years [50-88] and median ASA score was 3 [2-4]. Median aortic diameter was 56 mm [49-81]. Of the 100 external iliac access vessels, 14 had a diameter of 6 mm or lower. All endografts were successfully implanted. Post-operative Ultrasound examination and angioCT scan depicted both 1 type Ia, and 10 and 19 type 2 endoleaks respectively. An asymptomatic thrombosis of the left external iliac artery distal to the endograft limb was also depicted. 30-day mortality rate was 0%. Two patients died respectively three and four months after EVAR. Both deaths were not aneurysm related. All patients underwent an ultrasound exam 6-12 months after EVAR. All endografts main bodies and limbs were patent. Five endoleaks were depicted, all were type II endoleaks (the early type Ia endoleak had sealed spontaneously; it was confirmed by an angioCT scan). One patient presented a significant stenosis of the left iliac limb at the level of a narrow and calcified aortic bifurcation. It was successfully treated by bilateral iliac angioplasty and kissing balloon stenting.

CONCLUSIONS

EVAR performed with the Zenith LP main body in combination with Spiral-Z Iliac Legs is safe and effective. No limb occlusions were diagnosed at the 6 month follow up even in challenging iliac anatomies usually considered as contra indications for EVAR. Our first results are most satisfying and calling to be completed by a longer follow up.

Chronic type B dissections: are fenestrated and branched endografts an option?

While there are centers reporting encouraging outcomes after endovascular repair of thoracoabdominal aortic aneurysms, chronic dissections (a specific etiological subgroup of thoracoabdominal aneurysms) present an even greater technical and clinical challenge. There are particular technical issues associated with the management of the proximal sealing zone, the need to work in a narrow aortic lumen and also to maintain perfusion of all target (visceral and supra-aortic) vessels including those perfused by the false lumen. We present here the various endovascular options available for the treatment of these complex aortic lesions.

Fenestrated and branched technology: what's new?

This review article presents the latest published clinical series evaluating fenestrated and branched endografts for the treatment of complex aortic aneurysms incorporating the visceral branches, iliac arteries and supra-aortic trunks. In addition, an overview of the recent developments in devices and imaging modalities is also proposed.

[Language disorders in children with morphologic abnormalities of the hippocampus]

PURPOSE

Morphologic abnormalities of the hippocampal formations (MAHF) are more frequently observed in magnetic resonance imaging (MRI). We wished to specify the types of disorders associated with these malformations based on a retrospective case series by studying the language of the children presenting these abnormalities.

PATIENTS AND METHODS

From the data of all the MRIs taken in the neuroradiology ward of our center over 16 months in patients under 18 years of age, we retrospectively selected the children with an MAHF, isolated or associated with other malformations. The MAHFs were defined and described according to criteria of shape or orientation defects of the hippocampal formations. We studied the files of the patients with isolated MAHF again. Those whose clinical presentation was compatible with language assessment were tested in a prospective approach.

RESULTS

Out of 2208 MRIs from 1 January 2007 to 30 April 2008, 96 (4.3%) showed an MAHF, including 61 (64%) boys and 35 (36%) girls, aged from 2 months to 17 years. Eighty-two (85%) had associated abnormalities, mainly including cerebral atrophy, corpus callosum agenesis or defect, and abnormal ventricular frontal horns. Fourteen (15%) had an isolated MAHF: 2 on the left hemisphere, 2 on the right hemisphere, and 10 on both. Of these 14, 9 were compatible with language assessment. From the test results, we divided these children into 2 groups, depending on the type and severity of the impairment. Four had very serious language disorders as part of mental retardation or autistic disorders; 4 others had language disorders predominantly in expression and phonology, with weak to pathological visual memory. This study showed no potential relation between the lateralization of MAHF and language disorders, nor between the existence of epilepsy and the severity of the language disorders. Of these 14 children, 9 had behavior and autism spectrum disorders and 7 were epileptic.

CONCLUSION

Even though language disorders are often part of a larger deficiency presentation, the results we obtained suggest that isolated MAHFs are not only causes of amnestic disorders, but they could also directly underlie language disorders, particularly in expression.