Location Of Artery Research Articles

Ultrasound assessment of the frequency and variation of arteries in the interscalene region.

Given the abundance of arteries in the neck, a significant risk of puncturing arteries exists when performing a brachial plexus block. Therefore, it is important to confirm the presence of arteries when performing a brachial plexus block via the interscalene approach. This study aimed to investigate the frequency and variations of arteries in the interscalene region in healthy Japanese adults using ultrasonography. This is an observational study at a university hospital. We analyzed videos of the brachial plexus recorded in another study using an ultrasound device and then investigated the frequency of the presence of arteries and the location of arteries in the interscalene region. Among 68 cases, 48 (70.6%) had one or more arteries in the interscalene region (63 arteries in total). The artery frequency on the ventral side of the 5th cervical nerve (C5), between C5 and the 6th cervical nerve (C6), between C6 and the 7th cervical nerve (C7), between C7 and the 8th cervical nerve (C8), and on the dorsal side of C8 was 19.1%, 1.5%, 35.3%, 29.4%, and 7.4%, respectively. The artery frequencies between C6 and C7 and between C7 and C8 were higher than those between C5 and C6 and on the dorsal side of C8. Interscalene observations using ultrasound devices revealed a high artery frequency, with numerous topographic variations.

Comprehensive Management of Intracranial Aneurysms in Rare and Variant Arterial Locations: A Detailed Case Report

AbstractAneurysms on variant arteries, especially involving the persistent trigeminal artery (PTA), azygos artery, and lenticulostriate arteries (LSAs), are rare. This report presents a case and subsequent management of a patient with multiple unruptured aneurysms arising from variant anatomical structures. A 48-year-old patient with a history of worsening headaches presented with three unruptured aneurysms at the PTA, azygos artery, and left LSA, confirmed via catheter angiography with three-dimensional reconstruction. Given the potential effects on conventional cerebrovascular structures, managing multiple aneurysms in rare and variant locations requires a tailored strategy. This case was successfully treated with an endovascular approach and a period of observation, emphasizing the need for individualized treatment planning.

Pseudoaneurysm of the Lingual Artery in a Patient With Facial Trauma From Gunshot Wounds

A pseudoaneurysm is an abnormal dilatation within the wall of a blood vessel due to the formation of a hematoma in the vessel wall after vessel injury. Because of the protective nature of the facial skeleton and the deep location of the lingual artery, the lingual artery pseudoaneurysm is rare. The authors report a case of a 20-year-old male who suffered multiple gunshot wounds, including to the mouth, presenting with immediate life-threatening injuries. On hospital day 1, otolaryngology performed debridement of the mandible, retrieval and removal of bullet fragments, intermaxillary fixation, external fixation of the mandible, intra-oral laceration repair, repair of tongue laceration, and tracheotomy revision. On postoperative day 15, the otolaryngology service was called for the abrupt onset of major oral cavity bleeding. computed tomography-angiogram detected a pseudoaneurysm of the lingual artery and was successfully treated with endovascular coil embolization.

Genetic variants in patients with multiple arterial aneurysms

PurposeThe aim of this study was to identify causal genetic variants in patients with multiple arterial aneurysms.MethodsFrom a total cohort of 3107 patients diagnosed with an arterial aneurysm from 2006 to 2016, patients with known hereditary connective tissue diseases, vasculitis, or other arterial pathologies (n = 918) were excluded. Of the remaining cohort (n = 2189), patients with at least 4 aneurysms at different arterial locations (n = 143) were included. Nine blood samples of respective patients were available and derived from the institutional vascular biomaterial bank, and analyzed by whole exome sequencing (WES). Possible candidate variants were selected based on in silico predictions: (I) Truncating variants or (II) Variants that were classified as likely pathogenic (SIFT score < 0.05 or PolyPhen score > 0.9) and with low (< 0.001) or unknown gnomAD allele frequency. The human genome databases GeneCards and MalaCards were used to correlate the variants with regard to possible associations with vascular diseases.ResultsA total of 24 variants in 23 different genes associated with vascular diseases were detected in the cohort. One patient with eight aneurysms was heterozygous for a variant in SMAD3, for which pathogenic variants are phenotypically associated with Loeys-Dietz syndrome 3. A heterozygous variant in TNXB was found in a patient with five aneurysms. Homozygous or compound heterozygous pathogenic variants in this gene are associated with Ehlers-Danlos syndrome (classical-like). Another patient with six aneurysms carried two heterozygous TET2 variants together with a heterozygous PPM1D variant. Pathogenic variants in these genes are associated with clonal hematopoiesis of indeterminate potential (CHIP), a known risk factor for cardiovascular disease.ConclusionAll nine patients in this study carried variants in genes associated with vascular diseases. Current knowledge of the specific variants is insufficient to classify them as pathogenic at the present time, underlining the need for a better understanding of the consequences of genetic variants. WES should be considered for patients with multiple arterial aneurysms to detect germline variants and to improve clinical management for the individual and family members.

Palatal root endodontic microsurgery in maxillary molars using the palatal approach: a case study

BackgroundIn clinical practice, the buccal approach is typically the primary choice for endodontic microsurgery. Owing to the thickness of the buccal bone plate, the distance between the buccal bone plate and palatal lesion location, and soft tissue traction, the palatal approach may be more suitable for microsurgery for apical periodontitis of the palatal roots of the maxillary molars. However, the length of the palatal root, location of the greater palatine artery (GPA) and foramen (GPF), and surgical field of observation make palatal surgery challenging.Case presentationWith the aid of Cone-beam computed tomography imaging, the palatal approach was successfully applied in nine cases of endodontic microsurgery of the palatal root of a maxillary molar with a periapical lesion in Hangzhou Stomatology Hospital from January to December 2022.ConclusionsComplete healing was assessed based on clinical symptoms and radiographic images at the 3- and 24-month follow-up visits in all nine cases. Several tips have been proposed including surgical positioning, incision design, palate flap modification, bone removal, and root-end resection.

Number of attempts and interventions to obtain a valid pulmonary artery wedge pressure.

A valid pulmonary artery wedge pressure (PAWP) is essential for the hemodynamic characterization of pulmonary hypertension (PH). We prospectively investigated the methodology for obtaining a valid PAWP measurement, while assessing the impact of prespecified factors on its determination. In this prospective observational cohort study, we included consecutive patients who underwent right heart catheterization (RHC) using fluoroscopy at the Pulmonary Vascular Disease program at Cleveland Clinic, between February and May 2023. Once a valid PAWP was obtained, we recorded the number of attempts, reason for repeating the determination, pulmonary artery location, depth of the pulmonary artery catheter (PAC) from the introducer hub, and inflation volume of the PAC balloon. We included 195 patients, age: 57.5±15.7 years, 111 (57%) women, 156 (80%) with PH. The PAWP was 16.4±5.9 mmHg, requiring 1, 2 and ≥3 attempts for a valid measurement in 139 (71%), 39 (20%) and 17 (9%) patients, respectively. PAWP was repeated due to abnormal waveform, incomplete wedge and over wedge. A valid PAWP was obtained in the right pulmonary circulation in 168 (86%) patients, and in the lower third in 134 (69%), middle third in 58 (30%), and upper third of the lung in 3 (2%) patients. The pulmonary artery catheter balloon inflation at valid PAWP was 1.0±0.3 mL, at a distance from the introducer hub of 52.6±5.2 cm. Aspiration of blood in PAW position was obtained in 141 (72%) patients with an arterial oxygenation of 97% (95-99%). The number of measurements for a valid PAWP was directly associated with mean pulmonary artery pressure (mPAP) (r=0.18, P=0.01), PAWP (r=0.22, P=0.002), and pulmonary artery diameter on computed tomography (r=0.16, P=0.04). A valid PAWP was obtained during the first or second attempt in about 90% of patients that undergo RHC. Advanced interventions such as relocating the PAC to a different place of the same lung or contralateral pulmonary circulation are needed in about 10% of patients.

DeBakey Type III Aortic Dissection Causing Bowel Necrosis: A Case Report

Rationale: Aortic dissection is a life-threatening medical emergency associated with high morbidity and mortality. Preoperative mesenteric malperfusion increases the surgical risk and mortality in patients with type B aortic dissection. For DeBakey type III B patients involving most of the thoracoabdominal aorta, endovascular treatment to improve true lumen perfusion may have limited benefits. Organ reperfusion on-time is crucial. Patient concerns: A 38-year-old man was admitted with sudden severe upper abdominal pain. Emergency CTA of the entire aorta revealed an aortic dissection with an entry tear in the descending aortic arch involving the celiac trunk, superior mesenteric artery, bilateral common iliac arteries and right external iliac artery, with thrombosis in the superior mesenteric artery. Diagnoses: The patient was diagnosed with DeBakey type III aortic dissection with mesenteric artery embolism. Enhanced chest CT showed the entry tear location and involvement of major arteries. Angiography confirmed partial blood flow in the superior mesenteric artery. Interventions: The patient underwent endovascular aortic stent-graft implantation through the left femoral artery, covering the descending aortic arch and sealing the entry tear. Postoperatively, the patient received intensive care, including ventilatory support, CRRT, anti-infection therapy, vasoactive drugs and lumbar cistern drainage. Outcomes: Two weeks postoperatively, the patient developed massive black stools, indicative of intestinal obstruction and necrosis. Exploratory laparotomy revealed ischemic necrosis and rupture of the stomach, small intestine, and colon. Despite surgical efforts, the patient’s condition deteriorated, leading to death from severe infection, acid-base imbalance and multiple organ failure.

Are Hair Scalp Trace Elements Correlated with Atherosclerosis Location in Coronary Artery Disease?

Coronary artery disease is among the leading current epidemiological challenges. The genetic, clinical, and lifestyle-related risk factors are well documented. The reason for specific epicardial artery locations remains unsolved. The coronary artery topography and blood flow characteristics may induce local inflammatory activation. The atherosclerotic plaque formation is believed to represent inflammatory response involving enzymatic processes co-factored by trace elements. The possible relation between trace elements and coronary artery disease location was the subject of the study. There were 175 patients (107 (61) men and 68 (39) females) in a median (Q1-3) age of 71years (65-76) admitted for coronary angiography due to chronic coronary syndrome. The angiographic results focused on the percentage of lumen stenosis in certain arteries and were compared with the results for hair scalp trace elements. The correlation between left main coronary artery atherosclerotic plaques and nickel (Ni), zinc (Zn), and antimony (Sb) hair scalp concentration was noted. The analysis revealed a positive relation between left descending artery disease and chromium (Cr), sodium (Na), arsenic (As), and molybdenum (Mo) and a negative correlation with strontium (Sr). The atherosclerotic lesion in the circumflex artery revealed correlations in our analysis with sodium (Na), potassium (K), chromium (Cr), nickel (Ni), arsenic (As), and negative with strontium (Sr) (r) hair scalp concentrations. The negative correlations between right coronary artery disease and magnesium (Mg) and strontium (Sr) concentrations were noted. The possible explanation of different epicardial artery involvement and severity by atherosclerotic processes may lay in their topography and blood rheological characteristics that induce different inflammatory reactions co0factored by specific trace elements. The trace element concentration in the hair scalp may correlate with a particular coronary atherosclerotic involvement, including the severity of lumen reduction. This may indicate the missing link between the pathophysiological processes of atherosclerosis development and its location in coronary arteries.

Anatomic locations of ureterovascular fistulae: a review of 532 patients in the literature and a new series of 8 patients

IntroductionUreterovascular fistula (UVF) is a rare but potentially life-threatening condition. Since its primary description by Moschkowitz in 1908, many case reports, studies and reviews have been written about this condition with the suggestive symptoms and risk factors repeatedly discussed. This study will be focusing on the different locations of 532 out of 605 fistulae published from 1908 up to 2022 besides eight new patients of our own.Material and methodsA systematic review of the literature started using PubMed database searching for “ureteroarterial fistula”, “arteriovascular fistula” and “uretero vascular fistula” was performed yielding 122, 62 and 188 results respectively. Those studies and the cited literature in each study were examined to include studies, which did not appear in the primary search. A total of 605 patients in 315 publications were gathered. Only studies mentioning new patients, a clear indication of the location of the UVF, the presence/absence of urinary diversion (UD) as well as the type of UD if present were included. Ten duplicates as well as studies lacking information regarding the UVF and/or the UD (seven publications with 63 patients) were excluded, with 298 publications including 532 external patients remaining. Eight internal cases were included with a total of 540 cases.ResultsFrom the 540 included cases, 384 patients (71.1%) had no UD compared to 156 patients (28.9%) with UD. Due to the anatomical ureteral course, the common iliac artery (CIA) was the most common vascular component of UVF, irrespective of the presence or absence of UD. Any dispute to whether the crossing point is the common or the external iliac artery (EIA) was settled for the CIA. Further common vascular components besides CIA include the aorta, EIA, internal iliac artery (IIA) including its branches and vascular bypasses including the anastomosis sites. Other unusual arterial localizations were stated under the “others” category.ConclusionIdentifying the location of the bleeding artery in UVF is critical and represents the most important step for successful management. We present the largest summary of described locations up to date including our own.Graphical

Atypical de Winter ECG: What is the Culprit?

Various ECG patterns can help determine the location of the occluded coronary artery and the extent of threatened myocardium. The reported positive predictive value for de Winter ECG in predicting acute left anterior descending artery occlusion is inconsistent. Additionally, the morphology of ST depression and other ECG findings may have varying degrees of severity and prognostic significance. This case demonstrates the importance of integrating multiple ECG findings, such as ST elevation, Q waves, and the R/S ratio, with the location of the de Winter pattern on various ECG leads to accurately predict the culprit artery and assess the anatomical extent of myocardial ischemia.

Hand Acceleration Time is a Valuable Ultrasonographic Tool in Hand Perfusion as Adjuvant Evaluation for Diagnosing Chronic Upper Limb Ischemia

Diagnosis of chronic upper limb ischemia is mainly clinical. Although hand perfusion can be evaluated by different noninvasive methods (e.g., digital-brachial index, digital pressures, oxygen saturation measurements, and plethysmography), these have not been standardized for the diagnosis of chronic upper limb ischemia. Initial reports suggested that the hand acceleration time (HAT) measured by duplex ultrasound could be a useful diagnostic tool. However, the HAT has neither been properly characterized nor validated. This study aimed to provide evidence that HAT is a sensitive diagnostic tool for chronic upper limb ischemia. We conducted a prospective, single-center, cross-sectional study with adult patients diagnosed with chronic upper limb ischemia and healthy adult volunteers without cardiovascular risk factors. Hand vascular duplex ultrasound and HAT measurement were performed in 4 artery locations: princeps pollicis artery, radialis indicis artery, first common digital palmar artery, and third common digital palmar artery. It was also measured in the ulnar and radial arteries. Descriptive and exploratory analyses were performed between patients and healthy volunteers. Thirty participants were included, being 15 patients (median [standard deviation] age: 51 [18] years; 47% women) and 15 healthy volunteers (median [standard deviation] age: 35 [10] years; 60% women). In total, 15 ischemic and 30 nonischemic hands were analyzed. Humeral artery stenosis/occlusion (n=6, 40.0%) and distal artery stenosis (n=5, 33.3%) were the main causes of ischemia. Median (interquartile range) HAT measurements were significantly different between patients and healthy volunteers in the 4 hand arterial locations, the radial artery, and ulnar artery: princeps pollicis artery: 164 (124-252) vs. 60 (40-88), P<0.001; radialis indicis artery: 176 (140-348) vs. 60 (36-80), P<0.001; first common digital palmar artery: 180 (92-320) vs. 64 (36-88), P<0.001; third common digital palmar artery: 180 (104-240) vs. 56 (44-92), P<0.001; radial artery: 156 (120-248) vs. 68 (55-76), P<0.001; and ulnar artery: 152 (76-220) vs. 61 (48-76), P<0.001. Vascular duplex ultrasound with HAT measurement seems to be an easy-access, sensitive diagnostic tool for chronic upper limb ischemia. HAT provides valuable information on hand perfusion and may be complementary to current noninvasive methods.

The Genitofemoral Nerve Is the Structure Closest to the Tendon Footprint and Is Most at Risk for Iatrogenic Injury During Proximal Adductor Longus Repair: A Cadaveric Anatomy Study

To identify structures at risk during proximal adductor longus repair and to report observed distances between these structures and the adductor longus (AL) footprint. Eight hemipelves from fresh cadaver whole-body specimens were dissected using a previously established surgical approach. The tendinous attachment of the AL was scored into the underlying bone and the footprint size was measured in millimeters. A guidewire was placed at the footprint center along the longitudinal axis of the resected AL muscle. Utilizing a digital caliper, the proximity of key anatomic structures was measured as the radial distance from the guidewire and distance distal to the footprint along the guidewire axis. The AL footprint was on average 16.95 ± 3.02 mm wide by 9.36 ± 1.66 mm high. The ilioinguinal nerve was 27.10 ± 7.25 mm distal to the AL footprint and 31.75 ± 7.51 mm medial, with a resulting mean surface area of 158.12 ± 39.90 (110.9-230.2). mm2 The genital branch of the genitofemoral nerve was found 7.79 ± 4.05 mm proximal and 15.37 ± 4.54 mm medial. The round ligament (n= 6) was 14.00 ± 2.75 mm and the spermatic cord (n= 2) was 13.57 ± 3.02 mm directly superficial to the AL footprint. The obturator nerve was 63.98 ± 4.57 mm distal as it crossed the adductor brevis muscle laterally. The location of the external pudendal artery was variable but was found to have a mean distance of 37.01 ± 17.97 mm distal and immediately deep to the AL. When repairing AL tendon injuries, the genitofemoral nerve is the structure anatomically nearest the footprint of the tendon, and this structure is most at risk for iatrogenic injury. This study investigates the structures at risk during AL repair and seeks to define their location relative to the footprint. These findings will assist surgeons in identifying the crucial anatomic structures at risk to safely perform an anatomic repair of the tendon and avoid iatrogenic complications.

Vascular Plugs Improve Pulmonary Arteriovenous Malformation Occlusion over Coil Embolization Alone: A Proof-of-Concept Study Using Dual-Energy CT

PurposeTo evaluate effectiveness of pulmonary arteriovenous malformation (PAVM) embolization using dual-energy computed tomography (CT) and spectral curve analysis by characterizing contrast enhancement and vascular perfusion as a surrogate of the degree of vascular occlusion after embolotherapy. Materials and MethodsNine consecutive adult patients underwent embolization for 21 PAVMs (size range, 0.4–2.0 cm; 15/21 simple angioarchitecture) and subsequent postembolization chest dual-energy CT angiography. Twelve PAVMs were treated with vascular plugs with or without coils, whereas 9 PAVMs were treated with coils alone. Virtual spectral curves were generated using dual-energy image postprocessing in order to measure embolization effectiveness. ResultsComplete occlusion of target PAVM was achieved in all cases on digital subtraction angiography (DSA) at the end of the embolization procedure. With a median follow-up of 12.7 months, the vascular plug group demonstrated significantly less vascular opacification compared with the coils-only group, as measured by opacification between upstream feeding artery and different downstream vasculature locations (Δslope1: median 79.1 vs 28.6; P = .003; Δslope2: 76.4 vs 28.6; P = .0197; Δslope3: 78.9 vs 28.6; P = .004). Persistence occurred in 3 PAVMs based on size criteria, which demonstrated higher vascular opacification by dual-energy CT (Δslope1: 72 vs 28.6; P = .253; Δslope2: 65.1 vs 32.7; P = .326; Δslope3: 72.9 vs 53.5; P = .733), although statistical significance was not reached. ConclusionsSimilar to emerging literature, dual-energy CT showed improved occlusion in PAVMs treated with vascular plugs compared with those treated with coils alone.

Three-Dimensional Location of the Facial Artery in Relation to the Nasolabial Fold in Asian People: A Cadaveric CTA Study.

Injection cosmetics have become popular in recent years. The nasolabial fold is one of the most important and dangerous regions in the midface, and its three-dimensional relationship with the facial artery remains unclear. Fifty-two cadavers infused with lead oxide contrast medium via the external carotid arteries were scanned by computed tomography (CT). The three-dimensional model was reconstructed using Mimics and Origin software, and the relevant data were calculated using validated algorithms. There were three facial artery types according to its course in relation to the nasolabial fold. In the most common type, accounting for 83.7% of specimens, the facial artery evolves into an angular artery, with a horizontal distance between facial artery and nasolabial fold of - 1.90 ± 2.40, - 3.90 ± 2.95, - 5.18 ± 3.42, - 5.59 ± 3.53, - 5.59 ± 3.83, - 6.07 ± 4.10, - 6.92 ± 3.70, - 6.79 ± 3.37, - 4.52 ± 3.20, and - 2.76 ± 3.60 (mm) from the nasal ala to the oral commissure and a vertical distance of - 4.03 ± 2.56,- 3.27 ± 2.27,- 2.81 ± 2.57, - 2.1 ± 2.64,- 1.5 ± 3.32,- 0.71 ± 3.99,0.92 ± 4.43,0.4 ± 5.31,- 4.14 ± 5.14,- 7.05 ± 4.74 (mm). The facial artery is vulnerable to damage when injecting filler in the nasolabial fold. For the upper 1/3 of the nasolabial fold, the supraperiosteal layer is recommended for injection, while for the lower 2/3 of the nasolabial fold, the dermal layer along the nasolabial fold is recommended. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Intravascular Ultrasound during Endovascular Intervention for Peripheral Artery Disease, by Severity, Location, Device, and Procedure

There is limited evidence for the role of Intravascular Ultrasound (IVUS) in patients undergoing peripheral vascular intervention (PVI). We conducted retrospective cohort study utilizing the HCUP-AHRQ National Readmission database(NRD) to delineate outcomes in IVUS guided PVI versus non-IVUS guided PVI. The current study utilized NRD between January 1, 2016, and December 31, 2019. We identified patients undergoing endovascular intervention for peripheral artery disease using relevant ICD-10-PCS. The cohort was divided based on the use of IVUS during the procedure. The primary outcome was major amputation at 6 months after index hospitalization. Measured confounders were matched using propensity score inverse probability of treatment weighing method. We further performed a subgroup analysis based on disease severity, location of intervention, device, and procedure.A total of 434901 hospitalizations were included in the present analysis. PVI with IVUS compared with no IVUS had similar risk of amputation at 6 months (195 of 8939[2.17%] versus 10404 of 384003 [2.71%]);Hazard Ratio,0.98;CI, 0.77–1.25. Further, there was no difference in the rates of secondary outcomes. On subgroup analysis, amputation rates were significantly lower among patients with rest pain, in iliac intervention, or patients undergoing drug eluting stent implantation with the use of IVUS compared with no IVUS. This nationwide observational study showed that there was no difference in major amputation rates with the use of IVUS in patients undergoing PVI. However, in subgroup of patients with rest pain, iliac intervention or drug-eluting stent implantation IVUS use was associated with significantly lower major amputation rates.

A novel technique for the measurement of cervical length in non-pregnant women.

Cervical elongation is considered a risk factor for pelvic organ prolapse treatment failure in uterine preservation surgery. Consensus has not been reached regarding what is considered a normal cervical length, or how to measure it. Our primary aim was to test a new technique for measuring cervical length. We enrolled women undergoing hysterectomy, with or without pelvic organ prolapse (for all indications except cervical tumours/history of cervical operations). Their cervical lengths were measured both by ultrasound and anatomical measurement. The external length of the cervix was measured using Doppler location of the uterine artery near the cervical-uterine junction as the proximal point and compared to the ultrasound measurement of the cervical canal. The uterine specimen was used to record anatomical cervical measurements as well as uterine corpus length. Baseline characteristics such as age, body mass index and pelvic organ prolapse quantification were also collected. Twenty women were eligible for evaluation. We found the average anatomical cervical canal length was (ccAN) 33.95 mm (range ± 9.23) and by external measurement (ceAN) 36.80 mm (range ± 7.54). We found a significant, high-powered correlation between our ultrasound and anatomical measurements in both techniques, as well as between the two ultrasound techniques. We also found a negative correlation between cervical length and women's age (rp = -0.443, P = 0.05). Transvaginal ultrasound measurement of cervical length using the location of the uterine artery was found to have a strong correlation to the anatomical cervical length and can be used for the measurement of normal cervical length.

Optimal techniques of ultrasound-guided superficial and deep parasternal intercostal plane blocks: a cadaveric study

IntroductionThe optimal techniques of a parasternal intercostal plane (PIP) block to cover the T2–T6 intercostal nerves have not been elucidated. This pilot cadaveric study aims to determine the optimal injection...

Arterial Lesion Location and Outcomes of Intracranial Atherosclerotic Disease.

Intracranial atherosclerosis is a leading cause of stroke with a high recurrence rate despite treatment. Numerous factors are proposed to influence stroke recurrence due to intracranial atherosclerosis including lesion eccentricity, plaque characteristics, and computational fluid dynamic metrics, such as wall shear stress. An overlooked variable that intrinsically relates to intracranial atherosclerosis is the location of the arterial segment where the lesion occurs. Variations in cerebral blood flow, arterial anatomy, and flow dynamics are likely drivers of initial lesion development and thus likely to influence stroke recurrence. To date, treatment trials of intracranial atherosclerosis have not considered arterial segment lesion location as an independent variable, failing to account for variations in flow dynamics between each artery. There are limited available data on differences between arterial segments, confined to only post hoc analyses. In this review, we summarize available data on such differences between arterial segments. With the limited arterial segment data available, multiple differences in recurrence of stroke in territory of lesion were identified across trials.

Prevalence and anatomical factors associated with stent under-expansion in non-severely calcified lesions.

Stent underexpansion, typically related to lesion calcification, is the strongest predictor of adverse events after percutaneous coronary intervention (PCI). Although uncommon, underexpansion may also occur in non-severely calcified lesions. We sought to identify the prevalence and anatomical characteristics of underexpansion in non-severely calcified lesions. We included 993 patients who underwent optical coherence tomography-guided PCI of 1051 de novo lesions with maximum calcium arc <180°. Negative remodeling (NR) was the smallest lesion site external elastic lamina diameter that was also smaller than the distal reference. Stent expansion was evaluated using a linear regression model accounting for vessel tapering; underexpansion required both stent expansion <70% and stent area <4.5mm2. Underexpansion was observed in 3.6% of non-heavily calcified lesions (38/1051). Pre-stent maximum calcium arc and thickness were greater in lesions with versus without underexpansion (median 119° vs. 85°, p = 0.002; median 0.95 mm vs. 0.78 mm, p = 0.008). NR was also more common in lesions with underexpansion (44.7% vs. 24.5%, p = 0.007). In the multivariable logistic regression model, larger and thicker eccentric calcium, mid left anterior descending artery (LAD) location, and NR were associated with underexpansion in non-severely calcified lesions. The rate of underexpansion was especially high (30.7%) in lesions exhibiting all three morphologies. Two-year TLF tended to be higher in underexpanded versus non-underexpanded stents (9.7% vs. 3.7%, unadjusted hazard ratio [95% confidence interval] = 3.02 [0.92, 9.58], p = 0.06). Although underexpansion in the absence of severe calcium (<180°) is uncommon, mid-LAD lesions with NR and large and thick eccentric calcium were associated with underexpansion.

Establishing Safe Surgical Parameters for Placement of C2 Pedicle Screws: A Retrospective Study.

The study aimed to evaluate the safety and feasibility of transpedicular instrumentation for the C2 vertebra and to establish the precise anatomical parameters and boundaries within which this procedure can be safely and effectively performed. This retrospective study analyzed 66 patients who underwent C2 transpedicular screw fixation. Preoperative and postoperative axial, sagittal, and coronal computed tomography (CT) scans were examined. Anatomical measurements were taken to determine the horizontal and vertical distances from the C2 pedicle projection to the vertebral foramen using CT images. Based on the anatomical location of the vertebral artery within the C2 vertebral foramen, the patients were divided into four subgroups using the horizontal pedicle width (HPW) and vertical pedicle width (VPW) of the C2 spine. The average age of the patients included in the study was 46.48 years. The patient population comprised 32 (48.5%) males and 34 (51.5%) females. Based on the anatomical measurements, the distribution of C2 vertebra types was as follows: type 1 accounted for 68.9%, type 2 for 3.8%, type 3 for 16.7%, and type 4 for 10.6%. Significantly narrower pedicle widths were observed in types 2 and 4 compared to other vertebra types. Type 2 had the largest medial angle (MA), while type 4 had the narrowest MA. In terms of the sagittal plane, type 4 exhibited the widest MA and type 3 had the narrowest MA, but these differences were not statistically significant. Among the cases, 12 (18.1%) involved the vertebral foramen, with 1 case (8.3%) showing screw-related vertebral artery injury (0.75% of all screws). No vertebral artery injuries were observed with the other transpedicular screws. Preoperative anatomical measurements for patients undergoing transpedicular instrumentation on the C2 vertebra should include planning CT images on three planes: axial, sagittal, and coronal.