Comparison of intra-aortic computed tomography angiography to conventional angiography in the presurgical visualization of the Adamkiewicz artery: first results in patients with thoracoabdominal aortic aneurysms

Preoperative Spinal Arterial Supply Mapping Using Non-Selective Cone Beam Computed Tomography before Complex Aortic Repair

Pre-op spinal arterial mapping is crucial for complex aortic repair. This study explores the utility of non-selective cone beam computed tomography (CBCT) for pre-operative spinal arterial mapping to identify the Adamkiewicz artery (AKA) in patients undergoing open or endovascular repair of the descending thoracic or thoracoabdominal aorta at risk of spinal cord ischemia. Pre-operative non-selective dual-phase CBCT after intra-aortic contrast injection was performed in the aortic segment to be treated. The origin of detected AKA was assessed based on image fusion between CBCT and pre-interventional computed tomography angiography. Then, the CBCT findings were compared with the incidence of postoperative spinal cord ischemia (SCI). Among 21 included patients (median age: 68 years, 20 men), AKA was detected in 67% within the explored field of view, predominantly from T7 to L1 intercostal and lumbar arteries. SCI occurred in 14%, but none when AKA was not detected (p < 0.01). Non-selective CBCT for AKA mapping is deemed safe and feasible, with potential predictive value for post-surgical spinal cord ischemia risk. The study concludes that non-selective aortic CBCT is a safe and feasible method for spinal arterial mapping, providing promising insights into predicting post-surgical SCI risk.

Spinal dural fistula evaluation using 4-Dimensional intra-aortic spinal CTAngiography in a hybrid angiography suite

Intra-aortic CT Angiography (IA-CTA) is a relatively new technique that shows promise in efficient diagnosis and evaluation of the angioarchitecture of spinal dural arteriovenous fistulae(sdAVF). The authors document the first reported use of a 4D-CT and C-arm fluoroscope in a hybrid interventional suite to evaluate a sdAVF. Time resolved IA-CTA is clinically feasible in the evaluation of sdAVF, has higher temporal resolution as compared to standard IA-CTA and reduced contrast load, radiation dose and potential for procedural complications as compared to standard spinal angiography.

Staged hybrid repair of type II thoracoabdominal aneurysms

BACKGROUND

Open repair of type II thoracoabdominal aortic aneurysms (TAAAs) remains a challenging procedure. Staged procedures could decrease the incidence and severity of complications after complex aortic repair. In the present report, we have described a strategy using thoracic endovascular aortic repair (TEVAR) for proximal repair, followed by distal open repair.

METHODS

From 2014 to 2018, 14 patients had undergone TEVAR, followed by distal open repair, for type II TAAAs. All patients should have a suitable proximal landing zone according to the current guidelines. In cases of chronic dissection, false lumen embolization was performed to achieve total exclusion.

RESULTS

The mean patient age was 48 ± 15 years. Of the 14 patients, 5 had had Marfan syndrome (36%) and 6 had undergone previous aortic arch repair (43%). Ten patients had had a chronic dissection. The maximal aortic diameter was 73 ± 12 mm. The TEVAR technical success rate was 100%. The aortic length coverage was 211 ± 63 mm. The number of covered segmental arteries was 6 (range, 4-13). Two endoleaks were observed, one type Ib and one type II. The delay between TEVAR and open repair was 12 ± 8 weeks. Cerebrospinal fluid drainage was used in 13 patients. Six patients had undergone segmental artery reattachment during surgery. No spinal cord ischemic event was observed. One patient had died 5 weeks after open repair of multiple organ failure. During the 32 months of follow-up, no aortic-related deaths had occurred. No new aortic procedure was needed. The type Ib endoleak had resolved during open repair, and the type II TAAA had resolved spontaneously. The mean maximal thoracic aortic diameter had significantly decreased to 49 ± 8 mm (P < .0001). Aneurysmal shrinkage of ≥5 mm was observed in 13 patients (93%).

CONCLUSIONS

Staged hybrid repair of type II TAAAs appears to be efficient, with low morbidity and mortality rates. This technique could improve postoperative outcomes after open repair, and TEVAR might have a role in ischemic preconditioning to protect against spinal cord ischemia.

Advantages of 70-kV CT Angiography for the Visualization of the Adamkiewicz Artery: Comparison with 120-kV Imaging

BACKGROUND AND PURPOSE

Preprocedural identification of the Adamkiewicz artery is crucial in patients with aortic diseases. This study aimed to compare 70-kV CTA with conventional 120-kV CTA for the identification of the Adamkiewicz artery, examining differences in radiation dose and image quality.

MATERIALS AND METHODS

We retrospectively analyzed 2 equal groups of 60 patients who had undergone 70-kV or 120-kV CTA to detect the Adamkiewicz artery before aortic repair. Size-specific dose estimate, the CT number of the aorta, and the contrast-to-noise ratio of the anterior spinal artery to the spinal cord were recorded. Furthermore, detectability of the Adamkiewicz artery was evaluated by using a 4-point continuity score (3, definite to 0, undetectable).

RESULTS

There was significantly lower radiation exposure with 70-kV CTA than 120-kV CTA (median size-specific dose estimate, 23.1 versus 61.3 mGy, respectively; P < .001). CT number and contrast-to-noise ratio were both significantly higher in the 70-kV CTA group than the 120-kV group (999.1 HU compared with 508.7 HU, and 5.6 compared with 3.4, respectively; P < .001 for both). Detectability of the Adamkiewicz artery was not impaired in the 70-kV CTA group (90.0% versus 83.3% in the 120-kV group, P = .28). Moreover, the Adamkiewicz artery was detected with greater confidence with 70-kV CTA, reflected by a significantly superior continuity score (median, 3) compared with 120-kV CTA (median, 2; P = .001).

CONCLUSIONS

Seventy-kilovolt CTA has substantial advantages for the identification of the Adamkiewicz artery before aortic repair, with a significantly lower radiation exposure and superior image quality than 120-kV CTA.

Intraspinal hemangioblastomas: analysis of 92 cases in a single institution

Object

Intraspinal hemangioblastomas are relatively uncommon benign tumors. The surgical strategies remain controversial, and the risk factors with regard to clinical outcome are unclear. The purpose of this study was to analyze the clinical characteristics, imaging findings, surgical strategies, and functional outcomes associated with intraspinal hemangioblastomas.

Methods

A series of 92 patients who underwent 102 operations for resection of 116 intraspinal hemangioblastomas at a single institution during 2007–2011 were consecutively enrolled in this study. Of these, 60 patients (65.2%) had sporadic hemangioblastomas and 32 (34.8%) had von Hippel-Lindau disease. Preoperatively, 13 patients underwent digital subtraction angiography (DSA), 15 patients underwent 3D CT angiography (3D CTA), and none underwent preoperative embolization. Clinical characteristics, imaging findings, and operative records were analyzed. The advantages and disadvantages of DSA and 3D CTA were compared. For identification of risk factors that affect prognosis, logistic analysis was performed.

Results

The male/female patient ratio was 1.8:1.0 (59 male and 33 female patients). Of the tumors, 41% were intramedullary, 37% were intramedullary-extramedullary, and 22% were primarily extramedullary. Three-dimensional CTA and DSA did not differ significantly in the ability to identify the feeding arteries (p = 1.000) and image qualities (p = 0.367). However, compared with 3D CTA, the effective x-ray dose of spinal DSA was 2.73 times higher and the mean amount of contrast media injected was 1.88 times higher. Spinal DSA was more time consuming (mean 120 minutes) than 3D CTA (scanning time < 1 minute). No complications were observed after 3D CTA; acute paraparesis developed in 1 patient after DSA.

Gross-total resection was achieved for 109 tumors (94.0%), and resection was subtotal for 7 tumors. Mean duration of follow-up was 50 months (range 24–78 months). At the most recent follow-up visit, the functional outcome was improved for 38 patients (41.3%), remained stable for 40 (43.5%), and deteriorated for 14 (15.2%). Logistic analysis showed that subtotal resection was a risk factor affecting prognosis (p = 0.003, OR 12.833, 95% CI 2.429–67.806).

Conclusions

The authors' study suggests that safe and effective treatment of intraspinal hemangioblastomas can be achieved for most patients, even without preoperative embolization. Gross-total resection, when safe to perform, leads to better outcomes. Compared with spinal DSA, 3D CTA is a promising technique because it is noninvasive, takes less time to perform, requires lower x-ray doses and less contrast media, results in fewer complications, and offers high accuracy for delineating the feeding arteries.