Preoperative Computed Tomography Angiography Research Articles

The Value of Aortic Volume and Intraluminal Thrombus Quantification for Predicting Aortic Events after Endovascular Thoracic Aneurysm Repair.

Objectives: To assess the ability of the aortic aneurysm volume (AAV), aneurysmal lumen volume (ALV), and aneurysmal thrombus volume (ATV) to predict the need for aortic reintervention when using the maximal aortic diameter as a reference. Methods: This monocentric retrospective study included 31 consecutive patients who underwent successful thoracic endovascular aortic repair (TEVAR) to treat an atheromatous thoracic aortic aneurysm. All patients underwent clinical and computed tomography angiography (CTA) for 3 years after TEVAR. The patients were categorized into group 0 if no aortic reintervention was required during the follow-up period and categorized into group 1 if they experienced a type I or III endoleak or aneurysm diameter increase requiring intervention. The maximum aneurysm sac diameter and the AAV, ALV, and ATV were calculated using CTA images obtained preoperatively (T0) and at 6-12 months (T1), 24 months (T2), and 36 months (T3) postoperatively, and their changes over time were analyzed. Correlations between diameter and changes in AAV, ALV, and ATV were assessed, and the association between diameter and volume changes and reintervetion was examined. The cutoff values for predicting the need for reintervention was determined using a receiver operating characteristic (ROC) curve. The accuracy of volume change versus diameter change for predicting the need for reintervention was analyzed. Results: There were no significant differences in terms of the mean aneurysm diameter or AAV, ALV or ATV between the groups at preoperative CTA or after one year of follow-up imaging. The mean ATV was higher in group 1 than in group 0 at 2 years (187.6 ± 86.3 mL vs. 114.7 ± 64.7 mL; p = 0.057) and after 3 years (195.0 ± 86.7 mL vs. 82.1 ± 39.9 mL; p = 0.013). The maximal diameter was greater in group 1 than in group 0 at 3 years (67.3 ± 9.5 mm vs. 55.3 ± 12.6 mm; p = 0.044). The rate of AAV change between T0 and T1 was significantly higher in group 1 (7 ± 4.5%) than in group 0 (-6 ± 6.8%; p < 0.001). The rate of ATV change between T1-T3 was significantly higher in group 1 than in group 0 (34 ± 40.9% vs. -13 ± 14.4% (p = 0.041)); similar results were observed for the rate of ATV change between T2 and T3 (27 ± 50.1% for group 1 vs. -8 ± 49.5% in group 0 (p < 0.001)). According to our multivariate analysis, the annual growth rate for AAV between T0 and T1 was the only independent factor that was significantly associated with aortic reintervention (area under the curve (AUC) = 0.84, OR = 1.57, p = 0.025; optimal cutoff +0.4%). An increase in the annual growth rate of the ATV between T0 and T3 was independently associated with the need for aortic reintervention (area under the curve (AUC) = 0.90, OR = 1.11, p = 0.0347; optimal cutoff +10.1%). Conclusions: Aortic volume analysis can predict the need for aortic reintervention more accurately and earlier than maximal aortic diameter.

Anatomic Study of Vascular Supply of the External Ear Using CT Angiography in Congenital Microtia

Background: The morphology of the arteries of the external ear on the affected side of congenital microtia differs from normal. The present study aimed to use computed tomography angiography (CTA) to describe the anatomic variations of arteries in microtia and provide theoretical guidance for the first stage of autologous auricular reconstruction by the 2-stage method. Methods: Ten patients with unilateral microtia from May 2021 to August 2021 were included. Computed tomography angiography and 3-dimensional reconstruction were used to analyze the supply and branches of the main arteries of the auricle. The number of the superficial temporal artery (STA) and posterior auricular artery (PAA) branches to the auricle, vessel diameter, and the presence or absence of the STA and PAA branches were documented. The skin flap and incision were designed combined with the anatomic of auricular arteries. Results: The blood supply of the auricle mainly came from the STA and PAA. The STA’s preauricular branch and PAA’s posterior auricular branch were absent to varying degrees, and the middle branch was more prominent. The average diameter of the STA on the healthy auricle was 3.07±0.96 mm, and the average diameter of the PAA was 1.72±0.50 mm. The average diameter of the STA on the microtia auricle was 2.65±0.42 mm, and the average diameter of the PAA was 1.53±0.67 mm. There was a statistically significant difference in the diameter of STA between the healthy auricle and the microtia auricle (P=0.006). However, there was no significant difference in the diameter of the PAA between the healthy auricle and the microtia auricle (P=0.112). The skin flap and incision were designed and combined with the preoperative CTA images, and no flap necrosis was observed in all patients. Conclusion: The vascular distribution of arteries in microtia patients was clearly and accurately assessed by CTA. In our experience, the data and detailed imaging were useful in designing skin flaps and incisions during the first stage of autologous auricular reconstruction by the 2-stage method.

Examining the Impact of Median Arcuate Ligament-Induced Celiac Artery Compression on Target Vessel Patency and Long-term Survival and Device Integrity in Fenestrated and Branched Endovascular Repairs

To evaluate the impact of celiac artery (CA) compression by median arcuate ligament (MAL) on technical metrics and long-term CA patency in patients with complex aortic aneurysms (cAAs) undergoing fenestrated/branched endograft repairs (f/b-EVARs). Single center, retrospective review of patients undergoing f/b-EVARs and requiring incorporation of the CA between 2013 and 2023. Patients were divided into two groups - those with (MAL+) and without (MAL-) CA compression - based on preoperative computed tomography angiography (CTA) findings. MAL was classified in three grades (A, B and C) based on the degree and length of stenosis. Patients with MAL grade A had ≤ 50% CA stenosis measuring ≤ 3 mm in length. Those with grade B had 50%-80% CA stenosis measuring 3-8 mm long while those with grade C had >80% stenosis measuring > 8 mm in length. Endpoints included device integrity, CA patency and technical success - defined as successful implantation of the f/b-device with perfusion of CA and no endoleak. 180 patients with cAAs (pararenal: 128; thoracoabdominal:52) required incorporation of the CA during f/b-EVAR. Majority (73%) were male, with a median age of 76 (69, 81) years and aneurysm size of 62 (57, 69) mm. Seventy-eight patients (43%) had MAL+ anatomy, including 33 patients with MAL grade A, 32 with grade B and 13 with grade C compression. The median length of CA stenosis was 7.0 (5.0 - 10.0) mm. CA was incorporated using fenestrations in 177 (98%) patients. Increased complexity led to failure in CA bridging stent placement in four MAL+ patients but completion angiography showed CA perfusion and no endoleak, accounting for a technical success of 100%. MAL+ patients were more likely to require bare metal stenting in addition to covered stents (p=.004). Estimated blood loss, median operating room time, contrast volume, fluoroscopy dose and time were higher (p<.001) in MAL+ group. Thirty-day mortality was 3.3%, higher (5.1%) in MAL+ patients compared to MAL- patients (2.0 %). At a median follow-up of 770 (198, 1525) days, endograft integrity was observed in all patients and CA events - kinking (7), thrombosis (1) and endoleak (2) - occurred in 10 (5.6%) patients. However, only two patients required reinterventions. MAL+ patients had overall lower long-term survival. CA compression by MAL is a predictor of increased procedural complexity during f/b-device implantation. However, technical success, long-term device integrity and CA patency are similar to that of patients with MAL- anatomy.

THE SU-PERIOSTEUM: IMPROVING BONE BIOLOGY USING NOVEL CHIMERIC FIBULA-PERIOSTEAL FLAP

IntroductionThe presence of pluripotent mesenchymal cells in the periosteum along with the growth factors produced or released following injury provides this tissue with an important role in bone healing. Utilising this property, vascularised periosteal flaps may increase the union rates in recalcitrant atrophic long bone non-union. The novel chimeric fibula-periosteal flap utilises the periosteum raised on an independent periosteal vessel, thus allowing the periosteum to be inset freely around the osteotomy site, improving bone biology.Materials &amp; MethodsTen patients, with established non-union, underwent fibula-periosteal chimeric flaps (2016–2022) at the Canniesburn Plastic Surgery Unit, UK. Preoperative CT angiography was performed to identify the periosteal branches. A case-control approach was used. Patients acted as their own controls, which obviated patient specific risks for non-union. One osteotomy site was covered by the chimeric periosteal flap and one without. In two patients both the osteotomies were covered using a long periosteal flap.ResultsUnion rate of 100% (11/11) was noted with periosteal flap osteotomies, versus those without flaps at 28.6% (2/7) (p = 0.0025). Time to union was also reduced in the periosteal flaps at 8.5 months versus 16.75 months in the control group (p = 0.023). Survival curves with a hazard ratio of 4.1, equating to a 4 times higher chance of union with periosteal flaps (log-rank p = 0.0016) was observed.ConclusionsThe chimeric fibula-periosteal flap provides an option for atrophic recalcitrant non-unions where use of vascularised fibula graft alone may not provide an adequate biological environment for consolidation.

FL% is associated with the severity of acute DeBakey type I aortic dissection in patients undergoing frozen elephant trunk and total arch replacement.

The diameter, area, and volume of the true lumen and false lumen (FL) have been measured in previous studies to evaluate the extent of DeBakey type I aortic dissection. However, these indicators have limitations because of the irregular shapes of the true and false lumens and the constant oscillation of intimal flap during systole and diastole. The ratio of arch lengths seems to be a more reliable indicator. FL% was defined as the ratio of the arch length of FL to the circumference of the aorta at the different levels of the aorta. The purpose of this article was to investigate whether FL% is a predictor of the severity of acute DeBakey type I aortic dissection in patients undergoing frozen elephant trunk (FET) and total arch replacement. In this retrospective observational study, we analyzed a total of 344 patients with acute DeBakey type I aortic dissection that underwent FET and total arch replacement at our center from October 2015 to October 2019. The patients were divided into two groups by cluster analysis according to the perioperative course. Binary logistic regression analyses were performed to determine whether FL% could predict the severity of acute DeBakey type I aortic dissection. The area under the receiver operating characteristic curve (AUROC) was used to assess the power of the multivariate logistic regression model for the severity of acute DeBakey type I aortic dissection. The patients in the ultra-high-risk group (109 patients) had significantly more severe clinical comorbidities and complications than the patients in the high-risk group (235 patients). The ascending aortic FL% [odds ratio (OR), 11.929 (95% CI: 1.421-100.11); P = 0.022], location of initial tear [OR, 0.68 (95% CI: 0.47-0.98); P = 0.041], the degree of left iliac artery involvement [OR, 1.95 (95% CI: 1.15-3.30); P = 0.013], and the degree of right coronary artery involvement [OR, 1.46 (95% CI: 1.01-2.12); P = 0.045] on preoperative computed tomography angiography were associated with the severity of acute DeBakey type I aortic dissection. The AUROC value of this multivariate logistic regression analysis was 0.940 (95% CI: 0.914-0.967; P < 0.001). The AUROC value of ascending aortic FL% was 0.841 (95% CI: 0.798-0.884; P < 0.001) for the severity of acute DeBakey type I aortic dissection in patients undergoing FET and total arch replacement. Ascending aortic FL% was validated as an essential radiologic index for assessing the severity of acute DeBakey type I aortic dissection in patients undergoing FET and total arch replacement. Higher values of ascending aortic FL% were more severe.

The Impact of Technical Innovations and Donor-Site Mesh Repair on Autologous Abdominal-Based Breast Reconstruction-A Retrospective Analysis.

Background: The aim of this study was to examine the potential benefit that may be achieved through the introduction of technical innovations and the incorporation of mesh for fascial donor site closure in uni- and bilateral autologous breast reconstruction with abdominal tissue. Methods: A retrospective single-center review of all breast reconstructions with a DIEP or MS-TRAM flap between January 2004 and December 2019 was performed. Donor and recipient site complications and operation times were evaluated before and after the implementation of coupler anastomoses, preoperative computed tomography angiography (CTA), indocyanine green (ICG) angiography, and the inclusion of mesh in donor site repair. Results: A total of 396 patients were included, accounting for 447 flaps. Operation time was significantly shorter in unilateral reconstructions after the implementation of CTA (p < 0.0001). ICG angiography significantly reduced the rates of partial flap loss (p = 0.02) and wound healing disorders (p = 0.02). For unilateral reconstructions, abdominal bulging or hernia was observed more often in MS1-TRAM flaps without synthetic mesh repair (p = 0.001), whereas conservatively treated seroma developed more frequently after mesh implantation (p = 0.03). Conclusions: Recent technological advancements developed over the past few decades have made a substantial impact on decreasing surgical duration and enhancing procedure safety.

Geometric Analysis of the Gore Excluder Conformable Endoprosthesis in the Infrarenal Aortic Neck: One Year Results of the EXCeL Registry

The Gore Excluder Conformable Endoprosthesis (CEXC) is designed to treat challenging infrarenal anatomy because of its active angulation control, repositionability, and enhanced conformability. This study evaluated 30 day and one year position and apposition of the CEXC in the infrarenal neck. Patients treated with the CEXC between 2018 and 2022 with an available 30 day computed tomography angiography (CTA) were selected from four hospitals in a prospective registry. Endograft apposition (shortest apposition length [SAL]) and position (shortest fabric distance [SFD]) were assessed on the 30 day and one year CTAs. Maximum infrarenal aortic curvature was compared between the pre-operative and post-operative CTAs to evaluate conformability of the CEXC. There were 87 patients with a 30 day CTA, and for 56 of these patients the one year CTA was available. Median (interquartile range [IQR]) pre-operative neck length was 22 mm (IQR 15, 32) and infrarenal angulation was 52° (IQR 31, 72). Median SAL was 21.2 mm (IQR 14.0, 29.3) at 30 days for all included patients. The SAL in 13 patients (15%) was < 10 mm at 30 days, and one patient had a SAL of 0 mm and a type Ia endoleak. There was no significant difference in SAL between patients within and outside instructions for use. The SAL significantly increased by 1.1 mm (IQR -2.3, 4.7; p = .042) at 1 year. The SAL decreased in seven patients (13%), increased in 13 patients (23%), and remained stable in 36 patients (64%). Median SFD was 2.0 mm (IQR 0.5, 3.6) at 30 days, which slightly increased by 0.3 mm (IQR -0.5, 1.8; p = .019) at 1 year. One patient showed migration (SFD increase ≥ 5 mm). Median endograft tilt was 15.8° (IQR 9.7, 21.4). Pre-operative maximum infrarenal curvature was 36 m-1 (IQR 26, 56) and did not significantly change thereafter. In most patients, the CEXC was implanted close to the renal arteries, and sufficient (≥ 10 mm) post-operative apposition was acquired at 30 days, which slightly increased at one year. Post-operative endograft tilt was relatively low, and aortic geometry remained unchanged after implantation of the CEXC, probably due to its high conformability.

Preoperative Sizing to Lower In-Stent Restenosis in Peripheral Arterial Occlusive Disease

ObjectivesThe primary treatment for lower extremity peripheral arterial occlusive disease (PAOD) is angioplasty-stenting. Its main complication is in-stent restenosis. Poor selection of stent dimensions has been identified as a factor contributing to early in-stent restenosis. The aim of this study is to determine whether the implantation of stents, selected based on arterial morphological reconstruction using sizing software, reduces the occurrence of in-stent restenosis. The study also aims to evaluate the potential benefits of routine preoperative sizing. MethodsBetween January 2016 and December 2020, all patients treated for PAOD through scheduled angioplasty-stenting in our department were included in the study. Using systematic preoperative Computed Tomography Angiography (CTA), precise reconstruction and sizing were performed to select the ideal length and diameter of stents, resulting in the selection of a so-called IDEAL stent. During the procedure, the surgeon implanted either the IDEAL stent or a different one, named the ACTUAL stent, based on intraoperative data and/or availability. We compared the in-stent restenosis rate between IDEAL and ACTUAL stents. ResultsThere were no significant differences in the overall characteristics between the IDEAL and ACTUAL stent groups. The in-stent restenosis rate at one year was 13% (N=28/212, P=0.994) in the IDEAL group and 17% (N=25/149, P=0.994) in the ACTUAL group. Among the ACTUAL stents, a total of 19.6% of stents with a diameter mismatch when chosen based on arteriography showed a significantly higher restenosis rate during the first year of follow-up (P=0.02). ConclusionsOur study did not demonstrate a significant difference in 1-year restenosis rate between the IDEAL and the ACTUAL stents groups. It specifically revealed the significant impact of diameter selection on the intrastent restenosis rate during the first year of follow-up. Stents chosen based on arteriographic criteria, which exhibited diameter discordance, compared to the IDEAL stents group selected using sizing reconstructions, could be either oversized or undersized. This led to a significantly higher restenosis rate at 1 year postoperative.

Intravascular Iliac Artery Lithotripsy to Facilitate Aortic Endograft Delivery: Midterm Results of a Dual-Center Experience.

To assess the feasibility and safety of intravascular lithotripsy (IVL) for enabling transfemoral abdominal (EVAR), thoracic (TEVAR), and thoracoabdominal (BEVAR) endovascular aneurysm repair in patients with narrow and calcified iliac arteries. Consecutive patients treated with IVL for severe calcified and narrowed iliac access before EVAR, TEVAR, or BEVAR between November 2020 and June 2022 were retrospectively evaluated. All anatomical iliac characteristics were acquired by multi-planar reconstruction of preoperative computed tomography angiography (CTA). The hostility of the vascular accesses was classified based on Peripheral Arterial Calcium Scoring System (PACSS) and calcified access severity score (CASS), a new score considering both anatomical (calcium grade and length, minimum lumen diameter [MLD], and tortuosity index) and aortic stent-graft (SG/MLD index) parameters. Primary endpoint was technical success defined as successful aortic endograft delivery and deployment without iliac rupture. Freedom from complications and primary patency were additionally analyzed. Twenty-eight iliac axes were treated with IVL (8 bilateral) in 20 patients (mean age 74.5±6.7 years) with a mean follow-up of 26.5±6.2 (range 17-36) months. Ten patients underwent EVAR: 3 TEVAR, and 7 BEVAR procedures. In 14 patients (70%), aneurysm disease was associated with symptomatic aorto-iliac occlusive disease (AIOD), with Rutherford class III to IV. The PACSS was grade IV in 89% of the cases and the CASS (mean 14±2) was grade III to IV in all cases. The stent-graft (SG) outer diameter (5.60±1.65 mm) was significantly larger by 50% than MLD (3.96±1.20 mm), with an SG/MLD index of 1.50±0.51 (p<0.001). Technical success was 100%. No dissection, rupture, or distal embolization occurred. One (3.4%) bail-out stenting was necessary as endoconduit after IVL treatment. One month CTA showed that postoperative luminal gain increased by 93% (p<0.001). An improvement of 2 Rutherford classes occurred in all AIOD patients with a primary patency of 100% at last follow-up. This study shows the safety and feasibility of IVL as a valuable option to treat narrow and calcified iliac arteries to facilitate endograft delivery. Further studies will be useful to confirm these results. In this article, the use of intravascular iliac artery lithotripsy to facilitate aortic endograft delivery is explored. The presence of iliac severe calcifications still represents a contraindication for aortic endovascular repair. Intravascular lithotripsy increases the feasibility and safety of endovascular aortic procedures, facilitating endograft delivery and reducing the risk of iliac rupture and/or dissections by improving vessel compliance and luminal gain. This novel vessel preparation could be an alternative to "paving and cracking" and/or iliac conduits. This study describes a new score to classify the severity of iliac calcifications, considering anatomical parameters and the profile of aortic endografts delivery system.

Dysplastic aberrant left subclavian artery originating from a thoracic intersegmental artery associated with a right aortic arch.

A right aortic arch (RAA) is a rare vascular anomaly that often coexists with an aberrant left subclavian artery (ALSA). Due to the rarity of RAA, the development of an ALSA is not well understood. We describe a case in which a 58-year-old man who was scheduled to undergo posterior decompression and fusion surgery for thoracic ossification of the posterior longitudinal ligament from Th1 to Th3 was found to have a RAA and an ALSA. Preoperative computed tomography angiography demonstrated a RAA and an ALSA. The ALSA was extremely tortuous and ran in the paraspinal muscles behind the thoracic laminae, which meant it was in the surgical field. The ALSA arose from the descending aorta and bifurcated into the left segmental arteries of Th1 and Th2, and also bifurcated into the left vertebral artery, which had a normal subsequent course. The dysplastic ALSA was considered to have developed from the thoracic intersegmental artery. Based on preoperative examination findings, we performed spinal surgery without vessel injury. We report a rare case of a dysplastic ALSA that developed from the thoracic intersegmental artery with a RAA. The knowledge of this anomaly provides safety in spinal surgery of the cervicothoracic junction.

Emergency surgery for penetrating neck trauma and common carotid artery laceration presenting with shock: a case report

Introduction: The neck is an important anatomical junction connecting the head and limbs to the trunk and several vital neurovascular and aerodigestive structures pass through it. Zone II is the commonest site of penetrating neck injuries (PNI) and is commonly associated with vascular injury. The mortality rate following PNI is approximately 10%, increasing to 20% with concomitant penetrating carotid injury. Case description: A 43-year-old was brough to the emergency department in class III haemorrhagic shock with a 5mm, bleeding, penetrating neck injury in zone II of the neck. He had soft signs of vascular injury, bleeding was controlled with direct pressure, and resuscitation was commenced with intravenous crystalloids and blood products. Surgical exploration revealed a 5mm laceration in the distal common carotid artery which was repaired primarily. Postoperative computed tomography (CT) angiogram was normal and the patient had an uneventful recovery. Discussion: Traumatic disruption of the platysma is described as PNI and accounts for 10% of all penetrating injuries. Vascular injuries are most commonly seen in zone II and are usually associated with hard and soft signs of vascular injury. Zone II injuries require operative exploration with preoperative CT angiography recommended in haemodynamically stable patients to identify the type of injury. Small defects in the carotid artery can be repaired primarily. Conclusions: Open surgical exploration is mandatory for all patients with penetrative neck injury and haemodynamic instability. CT angiogram is recommended prior to open exploration is stable patients with zone II PNI.

Increasing DIEA Perforator Detail in 3D Photorealistic Volume Rendering Visualizations with Skin-masking and Cinematic Anatomy.

Preoperative CT angiography (CTA) is increasingly performed prior to perforator flap-based reconstruction. However, radiological 2D thin-slices do not allow for intuitive interpretation and translation to intraoperative findings. 3D volume rendering has been used to alleviate the need for mental 2D-to-3D abstraction. Even though volume rendering allows for a much easier understanding of anatomy, it currently has limited utility as the skin obstructs the view of critical structures. Using free, open-source software, we introduce a new skin-masking technique that allows surgeons to easily create a segmentation mask of the skin that can later be used to toggle the skin on and off. Additionally, the mask can be used in other rendering applications. We use Cinematic Anatomy for photorealistic volume rendering and interactive exploration of the CTA with and without skin. We present results from using this technique to investigate perforator anatomy in deep inferior epigastric perforator flaps and demonstrate that the skin-masking workflow is performed in less than 5 minutes. In Cinematic Anatomy, the view onto the abdominal wall and especially onto perforators becomes significantly sharper and more detailed when no longer obstructed by the skin. We perform a virtual, partial muscle dissection to show the intramuscular and submuscular course of the perforators. The skin-masking workflow allows surgeons to improve arterial and perforator detail in volume renderings easily and quickly by removing skin and could alternatively also be performed solely using open-source and free software. The workflow can be easily expanded to other perforator flaps without the need for modification.

Maxillary Artery Traversing Through the Temporal Muscle.

Few previous dissection reports demonstrated the possible course of the maxillary artery (MA) through the temporalis muscle (TM). A dissection study performed a long time ago established a 2% prevalence of this variant. As the variant was not studied on angiograms, we decided to do so. One hundred seventy archived computed tomography angiograms were used on 95 male and 75 female patients. The MA course through the TM was found in 11/170 cases (6.47%) but in 16/340 sides (5.58%). This is because, in 5/11 cases, the variant was bilateral. Therefore, preoperative computed tomography angiography could be helpful when surgical procedures using either the TM or the MA are designed. The course of the MA is variable, either deep or through the TM.

CT-derived fractional flow reserve in intracranial arterial stenosis: A pilot study based on computational fluid dynamics

BackgroundCT-derived fractional flow reserve (CT-FFR) has been widely applied in coronary hemodynamic assessment. However, the feasieablity and standardization measurement in intracranial artery stenosis (ICAS) remains to be defined. PurposeTo demonstrate the feasibility of CT-FFR in ICAS functional assessment and explore the optimal CT-FFR measurement position with invasive FFR as reference standard. Materials and methodsNineteen patients (mean age, 58.6 years ± 1.9 [SD]; 13 men) with moderate to severe (≥50 %) ICAS undergoing guidewire-based pressure measurement and preoperative head CT angiography (CTA) were retrospectively enrolled. CT-FFR was measured in the following standard measurement positions, including the end of stenosis (D0), 1 cm distal to the stenosis (D1) and 2 cm distal to the stenosis (D2). Diagnostic performance of CT-FFR was assessed by the area under the curve (AUC) of receiver operating characteristic curves by assuming invasive FFR ≤ 0.80 or 0.75 as hemodynamically significant stenosis. ResultsExcellent intra- and inter-observer agreement (ICC range, 0.930–0.992) was observed for CT-FFR measurement in different positions. Under different FFR thresholds, the diagnostic performance of CT-FFRD1 showed perfect prediction with AUC values of 1.000 (95 % CI: 0.824, 1.000). The sensitivity, specificity and AUC of CT-FFRD1 ≤ 0.80 in detecting FFR ≤ 0.80 was 0.94 (95 % CI: 0.68, 1.00), 1.00 (95 % CI: 0.31, 1.00) and 0.969 (95 % CI: 0.772, 1.000), respectively. Similar performance of CT-FFRD1 ≤ 0.75 was obtained for identifying FFR ≤ 0.75 with the AUC of 0.964. The strongest correlation (r = 0.915, p < 0.001) and agreement (mean difference: 0.02, 95 % limits of agreement: −0.16 to 0.19) were observed between CT-FFRD1 and FFR. ConclusionCerebral CT-derived fractional flow reserve (CT-FFR) measured 1 cm distal to stenosis achieved the most comparable results with invasive FFR, which indicated its potentially promising clinical application for evaluating the functional relevance of intracranial artery stenosis.

Predesigned chimeric deep inferior epigastric perforator and inguinal lymph node flap for combined breast and lymphedema reconstruction: A comprehensive algorithmic approach

The combined use of a deep inferior epigastric perforator (DIEP) flap coupled with vascularized inguinal lymph nodes (VILNs) for simultaneous breast and lymphedema reconstruction has already been well established, and promising results have been reported. However, a standardized approach for the planning and shaping of this combined flap is still lacking. We aimed to propose a comprehensive algorithmic approach for delayed unilateral breast and lymphedema reconstruction using a predesigned abdominal flap associated with inguinal lymph node transfer. We present in detail the preoperative measurements and surgical technique of the chimeric flap, which combines a predesigned DIEP template and a preselected inguinal lymph node flap, based on the preoperative computed tomography angiography and SPEC-CT findings, respectively; four different flap types are described according to the location of the pedicles of the two flap components. Our results of a series of 34 consecutive female patients with unilateral mastectomy and arm lymphedema, who underwent this combined predesigned reconstructive procedure, are retrospectively analyzed and reported. We recorded a high survival rate of the chimeric flaps in our series, with only one case of partial ischemic loss of a DIEP skin island. In the majority of our patients, the pedicles of the combined flaps were located in opposite positions. After a mean 35-month follow-up, we recorded a 47% mean volume difference reduction of the lymphedematous compared to the unaffected arm; no donor-site lymphedema was documented. Self-evaluation questionnaires showed high patient satisfaction rates regarding breast reconstruction. This algorithmic approach provides standardized guidance for accurate design and transfer of the DIEP-VILN chimeric flap while achieving highly satisfactory outcomes for both breast and lymphedema reconstruction.

Endovascular navigation in patients: vessel-based registration of electromagnetic tracking to preoperative images

Electromagnetic tracking of instruments combined with preoperative images can supplement fluoroscopy for guiding endovascular aortic repair (EVAR). The aim of this study was to evaluate the in-vivo accuracy of a vessel-based registration algorithm for matching electromagnetically tracked positions of an endovascular instrument to preoperative computed tomography angiography. Five patients undergoing elective EVAR were included, and a clinically available semi-automatic 3D–3D registration algorithm, based on similarity measures computed over the entire image, was used for reference. Accuracy was reported as target registration error (TRE) evaluated in manually selected anatomic landmarks on bony structures, placed close to the volume-of-interest. The median TRE was 8.2 mm (range: 7.1 mm to 16.1 mm) for the vessel-based registration algorithm, compared to 2.2 mm (range: 1.8 mm to 3.7 mm) for the reference algorithm. This illustrates that registration based on intraoperative electromagnetic tracking is feasible, but the accuracy must be improved before clinical use.

The profunda artery perforators: Anatomical study and radiological findings using computed tomography angiography in patients undergoing PAP flap breast reconstruction

The popularity of the profunda femoris artery perforator (PAP) flap is increasing; however, knowledge concerning the standardization of radiological findings and their clinical implications is limited. We evaluated the radiological architecture of posterior thigh perforators using Computed Tomography Angiography (CTA) to identify landmarks to facilitate flap dissection. A retrospective study was conducted on 35 patients who underwent unilateral breast reconstruction with a PAP flap. The preoperative CTA scans were analyzed, and the perforator characteristics were evaluated. The perforators were mapped using a Cartesian coordinate system. Data were normalized by anatomical landmarks and overlapped. Perioperative and postoperative results were analyzed. Radiological and intraoperative were compared. Two CTA scans were excluded; 66 thighs were examined. The mean perforator number was 3.2. The mean diameter of chosen perforators was 2.7mm (DS±0.6mm) at the origin, 2.2mm (DS±0.4mm) at the adductor space midpoint, and 1.7mm (DS±0.3mm) at the deep fascia. The mean adipose tissue thickness was 3.35cm (DS±0.94) at the deep fascia and 3.59cm (DS±1.19) at the adductor space midpoint. Intraoperatively, the perforator was located 3.22cm (DS±0.87) from the posterior border of the gracilis muscle and 8.98cm (DS±1.44) from the inferior gluteal crease. A radiological area located 9.33cm (DS±4.81) from the y-axis and 7.48cm (DS±1.88) from the x-axis was identified. CTA using the volume-rendering technique is a valuable method to study in vivo the radiological anatomy of the posterior thigh perforators.

Thin Calcification Predicts Lipid Component in Carotid Plaque—Relationship Between Lipid Distribution and Thin Calcification

BackgroundAccurately evaluating plaque characteristics is essential because lesions with lipid-rich plaque put patients at risk of thromboembolic complications from carotid artery stenting (CAS). Near-infrared spectroscopy (NIRS) is a diagnostic imaging modality that identifies lipid components from the near-infrared absorption pattern, but does not reveal the distribution of calcification. The purpose of this study was to investigate the calcification characteristics of unstable carotid plaques, focusing on relationships between the calcification characteristics revealed by computed tomography angiography (CTA) and the lipid core distribution derived from NIRS. MethodsParticipants in this retrospective analysis comprised 35 patients (29 men, 6 women; mean age, 76.0 years; range, 52–89 years) who underwent CAS in our institute between January 2021 and December 2022. We evaluated the thickness and length of carotid calcifications at the minimal lumen level from preoperative CTA and analyzed the relationship with maximal lipid core burden index (max-LCBI) from NIRS. ResultsStrong, negative linear correlations were observed between the thickness of calcification and max-LCBI at Area (any segment in a target lesion) (r=-0.795, p<0.001), max-LCBI at minimal lumen area (MLA) (r=-0.795, p<0.001) and LCBI at Lesion (rate of LCBI in entire plaque lesion) (r=-0.788, p<0.001), respectively. Significant negative linear correlations were observed between distribution of calcification length and max-LCBI at Area (r=-0.429, p=0.01), max-LCBI at MLA (r=-0.373, p=0.027) and LCBI at Lesion (r=-0.443, p=0.008). ConclusionsThin and ubiquitous carotid calcification was associated with LCBI values derived from NIRS indicative of carotid lipid plaque distribution, implying the possibility of predicting lesion instability.

Anatomic Feasibility of In-Situ Fenestration for Isolate Left Subclavian Artery Preservation during Thoracic Endovascular Aortic Repair Using an Adjustable Needle Puncturing System.

To evaluate the feasibility of thoracic endovascular aortic repair (TEVAR) using the Ankura™ device (Lifetech Scientific, Shenzhen, China) with left subclavian artery (LSA) in-situ fenestration (ISF) using an adjustable puncture device system. It is a single center, retrospective, financially unsupported cohort study of TEVAR performed from 16 February 2007 to 10 January 2023. Inclusion criteria were isolate LSA revascularization for elective or urgent/emergent "zone 2" TEVAR, and the availability of the preoperative computed tomography angiography. Post-hoc analysis identified 52 TEVARs. There were 39 (75.0%) males, and 13 (25.0%) females: median age was 74.5 years (IQR, 65.5-78). Index TEVAR was performed for atherosclerotic aneurysm in 27 (51.9%) cases, dissection-related diseases in 18 (34.6%), penetrating aortic ulcer in 5 (9.6%), and blunt traumatic aortic injury in 2 (3.8%). Access-vessel feasibility rate of TEVAR using the Ankura™ device would have been 98.1% (51/52). Considering the morphology of the aortic arch, ISF TEVAR feasibility would have been 61.5% (32/52). Binary logistic regression analysis identified LSA angulation (OR: 1.1, 95%CI: 1.03-1.14, p = 0.003) to be associated with ISF feasibility using this endograft and a self-centering adjustable needle-based puncture device. Potential feasibility of TEVAR using the Ankura™ endograft with ISF using a self-centering adjustable needle system was 61.5%. Left subclavian artery angulation seems to be the most important and limiting anatomical constraint.

Robot-Assisted Minimally Invasive Multivessel Coronary Bypass Guided by Computerized Tomography.

Robot-assisted minimally invasive coronary bypass surgery is one of the least invasive approaches that offers multivessel revascularization and accelerated recovery. We investigated the benefits of computed tomography angiography (CTA) guidance in robotic coronary bypass (RCAB) by analyzing perioperative outcomes. Between April 2022 and April 2023, 60 consecutive patients who underwent RCAB under preoperative CTA guidance were included. The intercostal space of the minithoractomy incision was determined based on the distance from the thoracotomy site to the midsection of the left anterior descending artery (LAD) on preoperative CTA. Peripheral vascular findings on preoperative CTA guided the decision for the cannulation site. Perioperative parameters and early outcomes were evaluated. The mean age of the patients was 62.3 ± 10.5 years, and 51 patients were male (85.0%). The mean number of revascularized vessels was 2.9 ± 1.1. Left thoracotomy guided by CTA measurements was performed in the fourth intercostal space in 37 patients (61.7%) and in the third intercostal space in the remaining patients. Axillary cannulation was performed in 28 (46.7%) patients because of prohibitive findings in the iliac vessels and aorta. All target coronary arteries with an indication for bypass were revascularized with CTA-guided RCAB. The left internal mammary artery (LIMA) was anastomosed to the LAD in all patients, and the LIMA was anastomosed sequentially to the diagonal artery in 17 patients (28.3%). No operative mortality or cerebrovascular event was observed. One patient underwent reoperation due to bleeding. Robot-assisted minimally invasive multiple-vessel coronary bypass under preoperative CTA guidance is safe and can be performed with excellent results.