3-dimensional Computed Tomography Angiography Research Articles

A giant liposarcoma originating from peripancreatic fat tissue with identification using 3D-CT angiography: a case report

BackgroundLiposarcoma originating from peripancreatic fat tissue is extremely rare. This case report presents a surgical case of a giant liposarcoma originating from peripancreatic fat tissue with origin identification using 3-Dimensional Computed Tomography Angiography (3D-CTA).Case presentationA 59-year-old female was referred to our hospital with a giant abdominal tumor. Computed tomography revealed a 34 cm tumor composed of fatty tissue, exerting pressure on the posterior aspect of the pancreas. Suspecting liposarcoma, we planned for surgery. At first, the tumor appeared to be intra-abdominal tumor, based on the identification of the tumor’s feeding artery as a branch of the dorsal pancreatic artery using 3D-CTA, we concluded that the liposarcoma originated from the peripancreatic fat tissue and situated in the retroperitoneum. During surgery, we observed a well-capsulated, elastic, yellowish mass without infiltration into surrounding tissues. We carefully dissected the tumor from the greater omentum and transverse mesocolon while preserving the tumor capsule. We ligated the feeding artery at the border with the pancreatic parenchyma and successfully completed the excision of the tumor. The resected specimen weighted 2620 g and was pathologically diagnosed as a well-differentiated liposarcoma. There was no injury to the tumor’s capsule, and the surgical margins were negative.ConclusionsIn this report, we present an extremely rare case of a liposarcoma originating in the peripancreatic fat tissue. The use of 3D-CTA was instrumental in identifying the primary site of this giant tumor, enabling us to guide the surgery and achieve complete resection successfully.

Clinical Impact and Determinants of Fenestration to Target Vessel Misalignment in Fenestrated Endovascular Aortic Repair

This single centre, retrospective study (2014 - 2022) on juxta-, pararenal, or thoraco-abdominal aortic aneurysms treated by fenestrated endovascular aortic repair (FEVAR) was conducted to investigate the clinical impact and determinants of fenestration to target vessel misalignment in FEVAR. Pre-operative supracoeliac, pararenal, and infrarenal aortic angles were measured on three dimensional computed tomography angiography (CTA) reconstructions. Two components of misalignment were measured on the first post-operative CTA: horizontal misalignment (angle between the fenestration and the target vessel ostium on perpendicular CTA cuts) and vertical misalignment (vertical distance between the fenestration and the target vessel at its origin). Endpoints were freedom from target vessel instability (TVI) and alignment change over time. Of 65 patients treated by FEVAR, 60 (202 target arteries) with juxta-, pararenal (80%), or thoraco-abdominal aortic aneurysm (20%) were included. Mean horizontal misalignment was 9 ± 12° (median 5°; IQR 0 - 16) and mean vertical misalignment was 0.7 ± 1 mm (median 0 mm, IQR 0 - 1). Freedom from TVI was 92% (95% CI 88 - 98) at 36 months. Horizontal misalignment > 15° was significantly associated with TVI (HR 5.19; 95% CI 1.54 - 17.48; p=.008); vertical misalignment did not significantly impact TVI (HR 0.99; 95% CI 0.56 - 1.73; p= .97). By multivariable analysis, pararenal aortic angle (OR 1.01 per increased degree of angulation; 95% CI 1.00 - 1.02; p= .044), bridging distance > 5 mm (OR 1.07; 95% CI 1.02 - 1.11; p= .003), and use of higher profile endografts in tortuous iliac access (OR 7.55; 95% CI 4.55 - 1.11; p= .003) were associated with clinically significant misalignment. Bridging distance > 5 mm (OR 2.00; 95% CI 1.02 - 11.29; p= .044), degree of baseline misalignment (OR 1.04; 95% CI 1.01 - 1.08; p= .036), and persistence of any primary endoleak for > 6 months (OR 5.85; 95% CI 1.23 - 29.1; p= .023) were associated with misalignment increase during follow up. Horizontal misalignment > 15° is associated with worsened target vessel outcomes. This may occur as a result of excessive iliac access tortuosity, high pararenal aortic angulation, and bridging distance > 5 mm.

Imaging features of cardioembolic stroke on 4-dimensional computed tomography angiography.

Identifying cardioembolic stroke is important for the decision-making of endovascular treatment and anticoagulation therapy. We aimed to explore the features of cardioembolic stroke on 4-dimensional (4D) computed tomography angiography (4D-CTA) and assess whether these features can assist in classifying stroke etiology. In this retrospective study, we analyzed the images of 294 patients with acute ischemic stroke (AIS) from July 2020 to February 2022 at the First Affiliated Hospital of Chongqing Medical University, which had been consecutively collected. The data of 110 patients with occlusion of the M1/M2 segment of the middle cerebral artery (MCA) with/without intracranial internal carotid artery (ICA) occlusion were analyzed to calculate the clot burden score (CBS) and collateral score (CS), and the data of 88 patients with a clear origin and distal part were analyzed to measure clot length. Maximum intensity projection (MIP) and time MIP (tMIP) post-processing were used to assess the clot features. The Mann-Whitney U test was used to compare the clot characteristics between the 2 groups. Binary logistic regression was performed to assess the association between the image characteristics and cardioembolic stroke. Moreover, the receiver operating characteristic (ROC) curve was used to test the diagnostic efficacy of MIP/tMIP clot features in classifying cardioembolic stroke. Age, high-risk factors for cerebrovascular disease, high/medium-risk sources of cardioembolic stroke, clot length, CBS, and CS were significantly different between the cardioembolic stroke group and non-cardioembolic stroke group (P<0.05). In the cardioembolic stroke group, the median MIP and tMIP clot length was 12 mm [interquartile range (IQR), 8.3-17.4 mm] and 9.3 mm (IQR, 6.8-14.3 mm), respectively. In the non-cardioembolic stroke group, the median MIP and tMIP clot length was 6.5 mm (IQR, 4.7-11.5 mm) and 5.8 mm (IQR, 3.9-10.6 mm), respectively. Binary logistic regression showed that cardioembolic stroke was significantly associated with MIP-clot length [odds ratio (OR), 1.15; 95% confidence interval (CI): 1.02-1.29; P<0.05], tMIP-clot length (OR, 1.18; 95% CI: 1.02-1.36; P<0.05), and tMIP-CBS (OR, 3.96; 95% CI: 1.08-14.58; P<0.05). The area under the ROC curve (AUC) values of MIP clot length for identifying cardioembolic stroke were 0.75 (95% CI: 0.65-0.84, P<0.05), with a cut-off value of >7.4 mm [sensitivity: 84.62% (95% CI: 69.50-94.10%); specificity: 59.18% (95% CI: 44.20-73.00%)]. The AUC value of tMIP clot length was 0.72 (95% CI: 0.61-0.81, P<0.05), with a cut-off value of >5.4 mm [sensitivity: 92.31% (95% CI: 79.10-98.40%); specificity: 48.98% (95% CI: 34.40-63.70%)]. Clot length and CBS were overestimated on MIP images. Among the clot characteristics, clot length could identify cardioembolic stroke.

Carotid Plaque Diagnosis With 3-Dimensional Computed Tomography Angiography: A Comparison With Magnetic Resonance Imaging-Based Plaque Diagnosis.

Although a qualitative diagnosis of plaque causing carotid stenosis has been attempted with carotid computed tomography angiography (CaCTA), no clear findings have been reported. We examined the correlation between the plaque CT values and plaque images obtained by magnetic resonance imaging to derive a qualitative diagnosis of the plaque using CaCTA. Preoperative CaCTA images acquired from patients stented for carotid stenosis were retrospectively analyzed with respect to magnetization-prepared rapid acquisition with gradient echo and time-of-flight magnetic resonance angiography data. Carotid plaques in the stenosed region were quantified in terms of CT density and the plaque/muscle ratio (magnetization-prepared rapid acquisition with gradient echo), and correlations between these 2 features were determined. Plaques were classified as stable or unstable based on the plaque/muscle ratio, with the smallest plaque/muscle ratio observed among plaques positive for intraplaque hemorrhage set as the cutoff value (1.76). A total of 165 patients (179 plaques) were included. Perioperative complications included minor stroke (n = 3), major stroke (n = 1, fatal), and hyperperfusion (n = 2). The correlation between CT density and the plaque/muscle ratio was nonlinear ( P = 0.0139) and negative ( P < 0.0001). The cutoff point (1.76) corresponded to a CT density of 83 HU, supporting this value as a standard reference for plaque stability. Computed tomography density exhibits a nonlinear ( P = 0.0139) and highly negative correlation ( P < 0.0001) with the plaque/muscle ratio. Our results demonstrate that plaque characteristics can be meaningfully diagnosed based on CaCTA image data.

A trial to visualize perforators images from CTA with a tablet device: experience of operating on minipigs

A reliable method for precise perforator mapping can be extremely valuable in perforator flap surgery. In this study, we attempted to map perforator location using 3-dimensional computed tomography angiography (CTA), a newly developed application, and a tablet device. Preliminary examinations to test the device were conducted in mini-pigs. We used 5 female mini-pigs. Preoperative imaging of the vasculature was undertaken with CTA in the prone position, following Iopamidol (200 ml) injection via the internal jugular vein. Prior to the examination, we placed round markers on the backs of the mini-pigs. To assess accuracy, we compared the perforator positions acquired with an optical position measurement device with the perforator positions acquired with the tablet device. Furthermore, we compared the perforator positions with the tablet navigation device, which we measured directly. We measured 12 perforators with the optical position measurement device. The mean difference was 10 mm (minimum, 2 mm; maximum, 20 mm). We measured these perforators with the tablet navigation device. The mean difference was 5.4 mm (minimum, 0 mm; maximum, 20 mm). The perforator flaps were elevated safely. The perforator flaps could be elevated safely using our device, as the mean difference was only 10 mm, which is acceptable for navigating perforator flap operations. Pig backs are triangular in shape; therefore, we were unable to place markers on the contralateral side. Thus, for clinical applications of the device, we should determine the ideal marker locations.

Feasibility of Preoperative Magnetic Resonance Angiography/Black-Blood Magnetic Resonance Imaging/Computed Tomography Fusion Imaging Without Contrast Agent for Carotid Endarterectomy

Preoperative identification of the carotid bifurcation (CB) location and plaque and stenosis distal end of the cervical internal carotid artery in relation to bony structures is essential for carotid endarterectomy (CEA). However, for patients with contrast contraindications, cervical 3-dimensional computed tomography angiography (3D-CTA) is unavailable. In this study, we created fusion images of magnetic resonance angiography (MRA), black-blood (BB) magnetic resonance imaging (MRI), and CT to determine if these noncontrast agent images are superior to 3D-CTA for preoperative CEA planning. The fusion images showed vascular structures obtained by MRA, plaque observed by BB-MRI, and bone structures shown by CT. Spatial localization accuracy was verified by directly overlaying contrast-enhanced 3D-CTA images on the fusion images. We validated this technique in 50 patients with unilateral ICA stenosis, 28 of whom underwent CEA. The 2D-distance CB MRA-CTA (the 2D distance difference between CB MRA and CB CTA perpendicular to the long axis of the carotid artery) was measured. We also compared the findings of the fusion image regarding the CB location and plaque distal end with the operative findings. The median 2D distance CB MRA-CTA was 1mm. CB MRA was located distal and proximal to CB CTA in 21and 29 patients, respectively. The CB location and fusion-image plaque were consistent with the intraoperative findings in all CEA patients. Fusion images created from MRA, BB-MRI, and noncontrast CT were feasible as an alternative to 3D-CTA for patients with contrast contraindications.

A dissection … of the Dacron?

A dissection … of the Dacron?

Elderly Man With Persistent Headache

A 68-year-old man presented to the emergency department with a persistent headache for 2 months. Vital signs showed a temperature of 36.7°C (98.06°F) and a normal pulse rate and blood pressure. The physical examination result was normal. Color Doppler ultrasonography of the neck vessels showed left internal carotid artery occlusion (Figure 1 and Video). Computed tomography (CT) showed multiple lacunar infarcts and 3-dimensional CT angiography revealed left internal carotid artery occlusion (Figure 2).

C1-2 Pedicle Screw Fixation for Ponticulus Posticus and Duplication of Vertebral Artery: 2-Dimensional Operative Video

We previously introduced C1 pedicle screw placement to treat C1-2 pathology in a patient with normal vertebral artery anatomy.1 However, we should prepare to meet various anatomic variations. Ponticulus posticus is a bony prominence arising from the posterior arch or the superior articulating process of the atlas that completely or partially encircles the vertebral artery.2 We herein report a 79-yr-old female who presented with myelopathy and was diagnosed with compressive myelopathy at the C1 level in magnetic resonance imaging. A computed tomography showed ponticulus posticus (complete type to the right side) with duplication of vertebral artery. She underwent surgical treatment of C1-2 pedicle screw placement and reduction of C1 vertebra under a microscopic view. After C1 laminectomy, both-side vertebral arteries were dissected with a microscissor. The mobilization of upper divisions of vertebral artery was identified to secure the entry point and pedicle to insert a C1 pedicle screw. After complete protection of the upper and lower divisions of vertebral artery and identification of pedicle, a C1 pedicle screw was inserted by a freehand technique. We inserted autologous bone chips in the distracted C1-2 facet joint for facet joint fusion, and the C1 vertebra was pulled out by a rod reducer. After surgery, the patient's symptoms disappeared, and no vertebral artery injury was identified in postoperative 3-dimensional computed tomography angiography. Patient consent was obtained prior to performing the procedure.

Numerical Simulation of Flow Behavior in Basilar Bifurcation Aneurysms Based on 4-Dimensional Computed Tomography Angiography

Initiation, growth, and rupture of cerebral aneurysms are caused by hemodynamic factors. It is extensively accepted that the cerebral aneurysm wall is assumed to be rigid using computational fluid dynamics (CFD). Furthermore, fluid-structure interactions have been recently applied for simulation of an elastic cerebral aneurysm model. Herein, we examined cerebral aneurysm hemodynamics in a realistic moving boundary deformation model based on 4-dimensional computed tomographic angiography (4D-CTA) obtained by high time-resolution using numerical simulation. The aneurysm of the realistic moving deformation model based on 4D-CTA at each phase was constructed. The effect of small wall deformation on hemodynamic characteristics might be interested. So, four hemodynamic factors (wall shear stress, wall shear stress divergence, oscillatory shear index and residual residence time) were determined from the numerical simulation, and their behaviors were assessed in the basilar bifurcation aneurysm.

Acute Lower Limb Ischemia Associated with COVID-19

A 75-year-old male patient without any significant medical and habitual risk factors for acute atherosclerosis obliterans except for hypertension was diagnosed with coronavirus disease 2019 with dyspnea, coughing, and mild fever. After a week of hospitalization, he complained of right foot pain and numbness. The symptoms were aggravated during the next week, resulting in a complete toe color change and loss of dorsalis artery pulse. Enhanced 3-dimensional computed tomography angiography revealed thrombus formation in the right common iliac artery and a loss of blood flow below the popliteal artery on both sides. The patient underwent percutaneous balloon angioplasty with stent insertion followed by medical therapy for anticoagulation. The clinical symptoms immediately were improved after the intervention, but the great toe necrosis was not recovered. Finally, amputation of the great toe was performed. [ABSTRACT FROM AUTHOR] Copyright of Journal of the Korean Orthopaedic Association is the property of Korean Orthopaedic Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Usefulness of Pointwise Encoding Time Reduction with Radial Acquisition and Subtraction-Based Magnetic Resonance Angiography after Cerebral Aneurysm Clipping

ObjectiveTime-of-flight magnetic resonance angiography (MRA) is limited by clip-induced artifacts after cerebral aneurysmal clipping. Recently, ultrashort echo time was shown to reduce metal artifacts. We assessed the pointwise encoding time reduction with radial acquisition (PETRA) sequence in subtraction-based MRA as an ultrashort echo time method during follow-up for clipping surgery.MethodsWe retrospectively evaluated 114 branches of 63 aneurysms in 56 patients treated with titanium clips using MRA and 3-dimensional computed tomography angiography. The appearance using each method was compared, and the associations between visibility on PETRA-MRA, clip number and shape, and amount of hematoma were examined. Furthermore, the visibility of the aneurysm remnants and 2 clipping cases with cobalt-chromium-nickel-molybdenum clips were evaluated.ResultsNo branches were visible using time-of-flight-MRA, but 79 of 114 branches (69.3%) were visible on PETRA-MRA. PETRA-MRA was effective for follow-up imaging in 33 of 63 aneurysms (52.4%). The median vessel diameters were 1.67 mm (interquartile range, 1.24–2.62 mm) and 0.96 mm (interquartile range, 0.59–1.53 mm) in the visible and invisible groups, respectively. Only the vessel diameter correlated significantly (P < 0.001) with the visibility on PETRA-MRA. A receiver operating characteristic curve for the association between the vessel diameter and visibility on PETRA-MRA showed a cutoff value of 1.26 mm for vessel diameter. Cobalt-chromium-nickel-molybdenum clips produced a strong artifact, even on PETRA-MRA. All 4 residual aneurysms were visible on PETRA-MRA.ConclusionsPETRA-MRA can be useful for follow-up aneurysm imaging when the diameter of vessels adjacent to the clip exceeds 1.26 mm. However, its usefulness is limited to titanium clips.

Letter: Identification of the Distal Dural Ring and Definition of Paraclinoid Aneurysms According to Bony Landmarks on 3-Dimensional Computed Tomography Angiography: A Cadaveric and Radiological Study

Letter: Identification of the Distal Dural Ring and Definition of Paraclinoid Aneurysms According to Bony Landmarks on 3-Dimensional Computed Tomography Angiography: A Cadaveric and Radiological Study

In Reply: Identification of the Distal Dural Ring and Definition of Paraclinoid Aneurysms According to Bony Landmarks on 3-Dimensional Computed Tomography Angiography: A Cadaveric and Radiological Study.

To the Editor: We greatly appreciate this interest in our work, and sincerely thank the authors for their comments.1 Surgical exploration is clearly the only way to determine the true relationship between an aneurysm and the distal dural ring (DDR). We thus could only statistically validate the DDR plane method using surgery. This provided statistical limits for our group of 27 patients without selection bias. Because this surgical group consisted only of intradural or transitional aneurysms because our practice does not treat asymptomatic extradural aneurysms surgically, we therefore could not demonstrate the applicability of the DDR plane method for extradural aneurysms using surgical exploration. Because of this limitation, we could only evaluate the DDR plane method using the T2-weighted magnetic resonance imaging-magentic resonance angiography fusion technique for extradural cases but could not use these patients for statistical validation. We agree that it is not realistic to have a diagnostic method with 100% accuracy, and certainly our small sample size is insufficient for high-powered statistical results with a narrow CI. To achieve a 95% CI with a 10% margin of error, we would need to evaluate more than 40 patients with transitional aneurysms within a population of 200 surgically treated paraclinoid aneurysms. Such a large number of cases is unrealistic even within a multicenter study. Anatomic studies and our cadaveric dissections confirmed that the DDR is attached to the optic strut (OS) superior border anteriorly.2-4 In previous radiological studies, it was found that using the OS as a reference point can be inaccurate for localizing paraclinoid aneurysms in medial or posterior locations.5 These findings can be explained by the fact that the DDR slopes downward in the medial and posterior directions and is not parallel to the planum sphenoidale.3 For this reason, we believe that our circumferential 3-dimensional DDR model is more accurate. As we all know, the geometric determination of a plane requires 3 noncollinear points. Thus, any points that are coplanar with the DDR could be used. For example, 3 points could be selected from the readily identifiable OS superior border. The problem is that the manipulations that could be made using the 3-dimensional computed tomography angiography reconstruction software at our institution (Vitrea version 6.7, Vital Images Inc, Minnetonka, Minnesota) were limited to the drawing of lines for defining a plane. We were unable to find a way to create a plane with this software that was defined by 3 points. As a result, we used 4 coplanar points around the DDR to define the imaginary plane. An important aspect for our selection of which points to use is that the opticocarotid elevation, the superior border of the OS, and the intersection between internal carotid artery (ICA) and anterior clinoid process (ACP) are located in 1 continuous line representing DDR bony attachments anterolaterally (Scerback et al,4 Figure 2); thus, any of these points can be selected to create the DDR plane. We selected 4 distant points to define the plane. These were the following: the anterior clinoid point in which the ICA intersects with the inferior border of the ACP (the intersection point is on the inferomedial border of the ACP; however, this may not be sufficiently clear on all images because of the 2-dimensional view); the lateral point of the OS superior border adjunct to the ACP attachment; the medial point of the optico-carotid elevation near the tubercullum sellae; the posterior point of the posterior clinoid process base. If some of these bony landmarks are blocked from view by the ICA, or more likely by a giant aneurysm, bone-subtraction computed tomography angiography can aid with imaging these points. The semitransparent view option for imaging vascular structures enables visualization of the DDR bony landmarks. The semitransparent viewing mode is also very useful for visualizing the parts of transitional aneurysms that are hidden by bony structures. In conclusion, we greatly appreciate the interest in this work and sincerely hope that readers will find our DDR plane method approach useful. Disclosures The authors have no personal, financial, or institutional interest in any of the drugs, materials, or devices described in this article.

Identification of the Distal Dural Ring and Definition of Paraclinoid Aneurysms According to Bony Landmarks on 3-Dimensional Computed Tomography Angiography: A Cadaveric and Radiological Study.

Determining if paraclinoid aneurysms are intradural or extradural is critical for surgical planning. To create an easily reproducible diagnostic method based on bony anatomy that precisely locates the distal dural ring (DDR) to determine the position of paraclinoid aneurysms as intradural, transitional, or extradural. Bilateral anatomic dissections of 10 cadaveric heads (20 sides) were performed to evaluate DDR anatomy. We observed a plane that reflects the position of the DDR passes through 4 bony landmarks: 1) The anterior clinoid-internal carotid artery intersection, 2) the optic strut, 3) the optico-carotid elevation, and 4) the base of the posterior clinoid process. This landmark-based plane can thus define the location of the DDR using 3-dimensional computed tomography angiography (CTA). This was confirmed in 27 surgical patients with intradural/transitional aneurysms and 7 patients with extradural aneurysms confirmed with magnetic resonance imaging (MRI). The DDR plane method easily classified aneurysm locations as intradural (above the DDR plane), extradural (below the DDR plane), or transitional (the DDR plane crosses the aneurysm). The aneurysm's location was subsequently confirmed intraoperatively or with MRI. The DDR plane method determined if paraclinoid aneurysms were intradural, transitional, or extradural in all 34 cases examined. The visibility of the anatomic features that define the DDR plane was also verified in 82% to 89% of CTA images from 100 patients. The DDR plane method provides a useful diagnostic tool to evaluate the position of the DDR and determine the anatomic location of paraclinoid aneurysms.

Embolization and sclerotherapy of maxillofacial arteriovenous malformations with the use of fibrin glue combined with pingyangmycin.

The objectives of this study were to document the results of using fibrin glue (FG) combined with pingyangmycin (PYM) for the embolism and sclerotherapy of maxillofacial arteriovenous malformations (AVMs). We reviewed the associated clinical data from December 2012 to June 2017 for 25 patients with maxillofacial AVMs. The major treatment method was direct percutaneous puncture and injection of FG combined with PYM. Treatment outcomes were assessed through physical examination, Doppler ultrasonography, computed tomography, and 3-dimensional computed tomography angiography scans. Follow-up time ranged from 12 months to 3 years after the last treatment (mean 21 months). Of the 25 lesions, 80% showed greater than 90% reduction, 12% showed greater than 75% reduction, and 8% showed greater than 50% reduction. Superficial skin necrosis or mucous ulcer occurred in 3 patients and healed without intervention. Regrowth was observed in 3 patients with extensive lesions involving multiple anatomic regions. These data suggest that embolization and sclerotherapy with the use of FG combined with PYM are safe and effective for the treatment of small- to medium-sized, locally dilated maxillofacial AVMs. For AVMs involving multiple anatomic regions, combined application of this approach with other options should be considered.

Effect of free medial plantar perforator flap in repairing deep burn wound on palm with the assistance of three dimensional computed tomography angiography

Objective: To explore the effect of free medial plantar perforator flap in repairing deep burn wound on palm with assistance of three dimensional computed tomography angiography (CTA). Methods: From March 2015 to January 2018, 11 patients with deep burn wounds of palm were admitted to the Department of Burns and Plastic Surgery of Yidu Central Hospital of Weifang City, including 6 males and 5 females, aged 19-53 years. The wound area after debridement was 3.0 cm×2.5 cm-8.0 cm×6.0 cm. Before the operation, CTA of the foot was performed, and the three dimensional digital model was reconstructed by computer software to observe the initial position, course, and distribution of the arteries and veins in the donor site. The medial plantar perforator flap was designed according to the area and shape of the wound, with area of 3.5 cm×3.0 cm-8.5 cm×6.5 cm. After the wound was covered by the flap, the perforating branch of the medial plantar artery was anastomosed end to end with the carpal epithelial branch of the ulnar artery, the accompanying vein or the branch of the great saphenous vein was anastomosed end to end with the accompanying vein of the carpal epithelial branch of the ulnar artery, and the terminal branch of the saphenous nerve or the medial dorsal cutaneous nerve was anastomosed end to end with the superficial palmar branch of the ulnar nerve. The wound of donor site was covered with full-thickness skin graft from the outer thigh of the same side. The perforators of the medial plantar artery observed during the operation were compared with the reconstructed three dimensional CTA images. The survival of flap was observed, and the appearance and function of the flap were followed up and evaluated with trial standard for the evaluation of the functions of the upper limbs of the Hand Surgery Society of the Chinese Medical Association. Results: The initial position, course, and distribution of the perforator of the medial plantar artery during the operation were basically the same as those of the reconstructed three dimensional CTA images before the operation. All the flaps of patients survived after the operation. During the 6 months to 1 year follow-up, the appearance of flap was good, with no obvious swelling or pigmentation, but with good elasticity. The discrimination distance between the two points was 5.0-8.0 mm, and the flaps were evaluated as excellent in 4 cases, good in 6 cases, and fair in 1 case. Conclusions: The free medial plantar perforator flap is an ideal choice for repair of the deep burn wound on palm. Three dimensional CTA before the operation can detect condition of vascular variation, with high accuracy of vascular anastomosis during operation.

Morphological and Hemodynamic Factors Associated with Ruptured Middle Cerebral Artery Mirror Aneurysms: A Retrospective Study

Mirror intracranial aneurysms with different rupture status is a useful model to investigate features associated with aneurysm rupture. Morphological and hemodynamic analyses of ruptured middle cerebral artery (MCA) mirror aneurysms are rarely reported. The purpose of this study was to determine the morphological or hemodynamic characteristics associated with ruptured MCA mirror aneurysms. We performed a retrospective analysis of consecutive 317 patients with MCA aneurysms. Ruptured MCA mirror aneurysms (1 ruptured and mirror unruptured aneurysm) were included. In the matched pairs of ruptured and unruptured mirror aneurysms, 13 morphological parameters were measured using 3-dimensional computed tomography angiography and 6 hemodynamic parameters were evaluated using high-resolution computational fluid dynamic simulations. The association of morphological and hemodynamic characteristics with the rupture of MCA mirror aneurysms was determined. A total of 20 (6.31%) patients with 40 MCA mirror aneurysms were included in this study. There were significant differences in morphological and hemodynamic parameters between the ruptured and unruptured mirror aneurysms. Irregular aneurysms were 3 times more common in the ruptured aneurysms than in the unruptured aneurysms. A larger aneurysm (P= 0.025), a higher aneurysm (P= 0.020), a larger size ratio (P= 0.009), a higher bottleneck ratio (P= 0.033), an irregular aneurysm (P= 0.022), a higher maximum intra-aneurysmal wall shear stress (WSS; P= 0.020), and a lower normalized average WSS (P= 0.008) were associated with MCA mirror aneurysm rupture. Larger aneurysms, a larger size ratio, irregular aneurysms, a lower spatial average WSS, and a higher maximum WSS may contribute to evaluating the risk of rupture of MCA aneurysms independent of patient characteristics.

Long-Term Clinical and Angiographic Outcomes of Wrap-Clipping for Ruptured Blood Blister-Like Aneurysms of the Internal Carotid Artery Using Advanced Monitoring

Wrap-clipping is one of the recommended treatments for ruptured blood blister-like aneurysms (BBAs) of the internal carotid artery (ICA). However, the long-term clinical and angiographic outcomes of this procedure have not yet been elucidated. The present study examined the long-term efficacy of wrap-clipping using a polytetrafluoroethylene membrane, an ideal wrapping material, for BBAs. The data from 9 patients with ruptured BBAs treated at our institutes from 2007 to 2016 were retrospectively analyzed. Wrap-clipping was performed with advanced monitoring techniques, including fluorescence video angiography and endoscopy. Angiographic follow-up was achieved using 3-dimensional computed tomography angiography or digital subtraction angiography. Clinical outcomes were assessed using the modified Rankin scale. Wrap-clipping was performed without any permanent morbidity in all patients. Endoscopy visualized accurate margins of the aneurysmal pathological wall with high magnification and revealed the position of the clip blades and the surrounding perforators in the dead angles of the microscope. Fluorescence video angiography could confirm the blood flow of the ICA and the surrounding arteries. Regrowth of the aneurysm owing to the presence of a neck remnant occurred 1 month after treatment in 1 case that was repaired surgically. However, no other recurrence of BBAs or progression of ICA stenosis was observed by angiography with a mean follow-up period of 37 months. No repeat rupture or ischemic complications occurred, and all patients had a modified Rankin scale score of 0 with a mean follow-up period of 61 months. Wrap-clipping using a polytetrafluoroethylene membrane for ruptured BBAs is a useful and acceptable procedure with long-term effectiveness. The effectiveness of this method can be ensured using modern monitoring methods.

Application of Microanastomosis Techniques in Vascular Neurosurgery Training and Innovation of Future Surgical Strategies for Giant Aneurysms

With the development of endovascular neurosurgery, fewer patients have been requiring surgery, and those who do require surgery have more complex cases. Thus, neurosurgeons better trained in microneurosurgery and clipping skills are needed. From 2014 to 2017, we built 296 aneurysms models from vessels harvested from chicken wings. The aneurysm models were created by anastomosing segments of arteries and veins with the same aneurysmal geometry and vascular relationships as in actual cases, using 3-dimensional computed tomography angiography. The models were injected with saline using a continuous infusion system, and different clipping techniques were attempted by different neurosurgeons. We have also described new technical solution for treatment of giant aneurysms, a surgical method that excludes them from flux using microsurgical endovascular bypass. We have described, in detail, the design for building middle cerebral artery, posterior communicating artery, anterior communicating artery, and basilar tip aneurysm models. All aneurysm models were patent, with no leakage points and with a good resemblance to the 3-dimensional computed tomography angiographic images that had served as the basis for the models. The aneurysm models were successfully clipped using different techniques. The neurosurgeons that trained on the aneurysm model before surgery found this experience useful. Aneurysm models respecting the real-case aneurysmal geometry provide a good training method for learning and preparing for surgery.