CT Angiogram Research Articles

The sphenopterygoid canal and pterygoid foramen.

In human anatomy, there are well-known the foramina of the greater sphenoidal wing, the foramen rotundum, the foramen ovale, the foramen spinosum, as well as the inconstant sphenoidal emissary foramen of Vesalius and the foramen of Arnold. Different canals are found in several species of rodents, such as the alisphenoid and sphenopterygoid (SPC) canals. It was re-explored an archived computed tomography angiogram of a 60 y.o. female case. Bilateral superior recesses of the pterygoid fossae (SRPF) and a right SPC were found. The SRPF on each side penetrated the non-lamellar pterygoid root and superiorly reached the sphenoidal sinus wall. Upper fibres of medial pterygoid muscles were inserted into each SRPF. An unexpected SPC was found on the right side. It opened superiorly on the lateral side of the foramen rotundum and inferiorly at a pterygoid foramen in the superior end of the posterior margin of the lateral pterygoid plate. A sphenoidal emissary vein traversed that SPC to drain into the pterygoid plexus. The SRPF and SPC could also be found in humans. As the sphenoidal emissary veins are surgically relevant, they should not be further regarded as exclusively crossing the foramen of Vesalius but also the SPC.

Saddle Pulmonary Embolus Treated With Bilateral Emergent Aspiration Pulmonary Thrombectomy

A 77 year old man with recurrent lower extremity thrombosis presented with acute onset shortness of breath and new onset hypoxemia three days after prostatectomy for adenocarcinoma of the prostate. He had been off anticoagulation during the perioperative period. In addition to his new diagnosis of prostate cancer he also had a remote history of treated non-invasive melanoma. Based on this presentation he was at high risk of developing thromboembolic disease. Computed tomography angiogram (CTA) of his chest confirmed a large saddle pulmonary embolus, echocardiogram was positive for new right ventricular wall motion dyskinesis and lower extremity ultrasound revealed bilateral acute and chronic deep vein thrombosis. Given his high bleeding risk, hypoxia and elevated troponin I, he underwent emergent successful aspiration pulmonary thrombectomy. This case is of interest to hospitalists and intesivists as it provides an overview of the current invasive management of pulmonary embolus in the acute setting when systemic anticoagulation is contraindicated. Emergent Aspiration Pulmonary Thrombectomy can restore pulmonary artery flow and cardiopulmonary hemodynamics. A collaborative team based approach that involves the emergency department, intensive care unit, interventional teams and hospitalists is favored.

Vertebral Artery Injury in Cervical Spine Fracture Dislocation: An Observational Study in a Tertiary Care Center.

The incidence of traumatic vertebral artery injury (VAI) associated with cervical spine trauma varies widely in published trauma series. The primary aim of this study was to determine the incidence of traumatic VAIin patients who suffered cervical spine injuries by means of routine magnetic resonance imaging, and the secondary objective was to identify any associations with injury mechanism, level ofinjury, and neurologic injury severity. Materials and methods: A retrospective review was conducted on 96 patients who suffered cervical spine fracture dislocation with or without an associated spinal cord injury (SCI) in Indian Spinal Injuries Center (ISIC), New Delhi, Indiafrom January 2013 to April 2023. Cervical magnetic resonance imaging (MRI) was used to diagnose VAI. Patient's age, sex, cervical injury level, mechanism of injury, neurologic level of injury, association with foraminal fracture, facet dislocation,and clinical sequelae of vertebral artery injury were analyzed. In this study, of 96 patients who met the inclusion criteria, 18 patients (18.75%) had VAI on the MRI study. Thirteen (72.22%) of the eighteen patients had right-sided injuries, four (22.22%) had left-sided injuries, and one (5.55%) had bilateral injuries. There was an associated SCI in every VAI patient. VAI was significantly more common in patients who had ASIA A (61%, n = 11) and ASIA B (22%, n = 4)injuries, and no VAI was noted in neurologically intact patients (p<0.001). The incidence of VAI was higher in the flexion distraction type of injury (n = 12, 66%).The most commonly involved cervical spine injury level was C5-C6 (27%, n = 5), followed by 22% (n = 4) at C4-C5 and C6-C7 levels. About 27.8% (n = 5) of VAI was associated with foraminal fractures, and 72% (n = 13) of VAI was associated with facet dislocations, of which 44% (n = 8) were bifacetal and 28% (n = 5) were unifacetal dislocations. On clinical symptoms, only one (5.56%) patient had a headache, and 17 (94.4%) had no clinical features due to VAI. The incidence of traumatic vertebral artery disease is not very uncommon and requires careful and meticulous screening and management. Otherwise, complications like pseudoaneurysm, neurologic deficit, late-onset hemorrhage, infarction, and death can happen. Mostly, it is associated with high-velocity injuries and neurological injuries. MRI can be used as a good screening tool, which can be aided by a CT angiogram or digital subtraction angiographyfor confirmation. Proper pre-operative evaluation of vascular injury in cervical spine fracture dislocation is very important for patient counseling, patient management, and surgical planning.

THEME: EVALUATION OF THE TECHNIQUE OF PERFORMING ANGIO-SCANNING AT CHME LUXEMBOURG

Objectives :Evaluate the technique of performingangio-scanning at CHME Luxembourg. Methodology: This is a 2-month prospective and descriptive studyfrom April 1 to May 31, 2021. Any patient presenting an examination bulletin sent to the imagingdepartment for angio-CT and havingagreed to participate in ourstudy. Results:Duringourstudyperiod, 1025 CT scans wereperformed, amongwhichwefound 78 angio-CT scans, representing a frequency of 7.60%. Among the 78 cases of CT angioperformed, weidentified 61 angio-thoracic (78.20%), 7 lowerlimbangio (7.90%), 5 thoraco-abdominopelvicangio-CT (6.40%). , 3 cerebral CT angio-CT (3.80%) 1 CT angiogram of the upperlimbs and the aortawith a frequency of 1.30% each. The averageage of our patients was 57 yearswithextremes of 1 month (born) and 82 years. The femalegenderwas the mostrepresentedwith 53%. Dyspnea and chest pain were the mostcommonclinicalfindings. Meglumineioxitalamate (Télébrix*) was the mostusediodinatedcontrastproductwith 65.4%. The average flow rate was 3.92 ml/s in ourstudy. The average value of Dose-Length-Product (DLP) per acquisition was 353.79 mGy.cm withextreme values ​​of 91 to 775mGy.cm. Hot flashes were the mostfrequentlyencounteredsideeffect in our patients with a frequency of 26.9%. Among the angio-TTDM performed, 80.8% of ourexaminationscorresponded to the successcriteria Conclusion: The CT angiography technique remains the gold technique for the exploration of veins and arteries. In the majority of cases it leads to a satisfactorydiagnosis.

ANGIOEMBOLISATION OF CREMASTERIC ARTERY FOR SCROTAL HAEMATOMA FOLLOWING HERNIAL REPAIR

Cremasteric artery is a branch of inferior epigastric artery supplying the cremaster muscle and coverings of the cord. The possible consequence of injury to this artery is scrotal haematoma. We present a case of haemorrhage from unexpected cresmastric artery injury post-hernioplasty treated with angioembolisation. To the best of our knowledge, this has not been reported in literature.&#x0D; A 66-year-old gentleman with left indirect inguinal hernia underwent a left inguinal hernioplasty in our institution with no immediate complications. However he presented to the emergency department the day after the procedure with complaints of rapidly worsening painful left scrotal swelling accompanied with symptoms of intestinal obstruction. Emergency laparotomy and re-do left hernioplasty was performed, revealing a strangulated inguinoscrotal hernia. Post-operatively, there was non-resolving scrotal swelling with a drop in the haemoglobin level; from 11.9g/dl to 8.5g/dl requiring packed cell transfusion. CT angiogram revealed active contrast extravasation from the left cremasteric artery. Angiographic run confirmed the finding and the left cresmatric artery was superselectively cannulated with a 1.9Fr microcatheter and embolization done with 0.5mm microcoil. Ultrasound scan 24-hour post-procedure showed patent proximal vessel. Clinically there was a reduction of the left scrotal swelling and the haemoglobin remained stable. &#x0D; Cremasteric artery courses laterally deep into the fascia transversalis entering the cord deep to the internal spermatic fascia to supply the cremaster muscle and coverings of the cord. This course renders the artery to be prone for injury during procedure such as hernioplasty; one of the possible consequences is scrotal haematoma. This artery is usually small in caliber and its identification is important for efficient and effective treatment.&#x0D; Angioembolisation is able to treat this injury with superior precision owing to its ability for localization and selective cannulation of the offending vessel.

Pancreatic cyst prevalence and detection with photon counting CT compared with conventional energy integrating detector CT

PurposeTo calculate the prevalence of pancreatic cysts on photon counting CT (PCCT) and compare with that of 128-slice conventional energy-integrating detector CT (EIDCT). MethodA retrospective single institution database search identified all contrast-enhanced abdominal CT examinations performed at an outpatient facility that has both a PCCT and EIDCT between 4/11/2022 and 7/26/2022. The presence and size of pancreatic cysts were recorded. In patients with PCCT reported pancreatic cysts, prior CT imaging (EIDCT) was reviewed for reported pancreatic cysts. Fisher’s exact test was used to compare the pancreatic cyst detection rate for PCCT and EIDCT. Wilcoxon rank sum test was used to compare cyst size and patient age. A p <.05 indicated statistical significance. Results2494 patients were included. Our pancreatic cyst detection rate was 4.9 % (49/1009) with PCCT and 3.0 % (44/1485) for EIDCT (p =.017). For CT angiograms, pancreatic cysts were detected in 6.6 % (21/319) with PCCT and 0.0 % (0/141) with EIDCT (p <.001). Pancreatic cyst detection rate was not statistically different for portal venous, enterography, renal mass, pancreas, 3-phase liver, or venogram protocols (all p >.05). Mean[SD] pancreatic cyst size was 13.7[9.7]mm for PCCT and 15.3[14.7] for EIDCT (p =.95). 55.1 % (27/49) of PCCT and 61.4 % (27/44) of EIDCT that described pancreatic cysts had prior contrast-enhanced EIDCTs. Of these, 40.7 % (11/27) of PCCT and 14.8 % (4/27) of EIDCT described pancreatic cysts were not previously reported (p =.027). ConclusionsPhoton-counting CT afforded greater pancreatic cyst detection than conventional energy-integrating detector CT, particularly with CT angiograms.

Exploring the role of in-patient magnetic resonance imaging use among admitted ischemic stroke patients in improving patient outcomes and reducing healthcare resource utilization.

Despite the diagnostic and etiological significance of in-patient MRI in ischemic stroke (IS), its utilization is considered resource-intensive, expensive, and thus limiting feasibility and relevance. This study investigated the utilization of in-patient MRI for IS patients and its impact on patient and healthcare resource utilization outcomes. This retrospective registry-based study analyzed 1,956 IS patients admitted to Halifax's QEII Health Centre between 2015 and 2019. Firstly, temporal trends of MRI and other neuroimaging utilization were evaluated. Secondly, we categorized the cohort into two groups (MRI vs. No MRI; in addition to a non-contrast CT) and investigated adjusted differences in patient outcomes at admission, discharge, and post-discharge using logistic regression. Additionally, we analyzed healthcare resource utilization using Poisson log-linear regression. Furthermore, patient outcomes significantly associated with MRI use underwent subgroup analysis for stroke severity (mild stroke including transient ischemic attack vs. moderate and severe stroke) and any acute stage treatment (thrombolytic or thrombectomy or both vs. no treatment) subgroups, while using an age and sex-adjusted logistic regression model. MRI was used in 40.5% patients; non-contrast CT in 99.3%, CT angiogram in 61.8%, and CT perfusion in 50.3%. Higher MRI utilization was associated with male sex, younger age, mild stroke, wake-up stroke, and no thrombolytic or thrombectomy treatment. MRI use was independently associated with lower in-hospital mortality (adjusted OR, 0.23; 95% CI, 0.15-0.36), lower symptomatic neurological status changes (0.64; 0.43-0.94), higher home discharge (1.32; 1.07-1.63), good functional outcomes at discharge (mRS score 0-2) (1.38; 1.11-1.72), lower 30-day stroke re-admission rates (0.48; 0.26-0.89), shorter hospital stays (regression coefficient, 0.92; 95% CI, 0.90-0.94), and reduced direct costs of hospitalization (0.90; 0.89-0.91). Subgroup analysis revealed significantly positive association of MRI use with most patient outcomes in moderate and severe strokes subgroup and non-acutely treated subgroup. Conversely, outcomes in mild strokes (including TIAs) subgroup and acute treatment subgroup were comparable regardless of MRI use. A substantial proportion of admitted IS patients underwent MRI, and MRI use was associated with improved patient outcomes and reduced healthcare resource utilization. Considering the multifactorial nature of IS patient outcomes, further randomized controlled trials are suggested to investigate the role of increased MRI utilization in optimizing in-patient IS management.

A radio-anatomical study of median arcuate ligament syndrome: unveiling the morphology and morphometry of median arcuate ligament, celiac trunk, and superior mesenteric artery.

In the context of medical literature, a significant lacuna exists in understanding median arcuate ligament syndrome (MALS). While clinical aspects are well documented, literature lacks a robust exploration of the anatomical relationship between the celiac trunk and the median arcuate ligament (MAL). Morphometric parameters, including the vertebral level of MAL origin, MAL thickness, celiac trunk (CeT) origin level, diameter, and distances between CeT/Superior Mesenteric Artery (SMA) and the MAL center were observed on 250 CT angiograms. Cadavers (n = 11) were dissected to examine the same parameters and histo-morphological examination of MAL tissue was done. Radiological findings established average MAL thickness of 7.79 ± 2.58mm. The celiac trunk typically originated at T12. The average distance between the celiac trunk and the MAL center was 1.32 ± 2.04mm. The angle of the celiac trunk to the abdominal aorta was primarily obtuse. The average celiac trunk diameter was 5.53 ± 1.33mm. Histological examinations revealed a diverse MAL composition, indicating variable mechanical properties. This study provides comprehensive morphometric data on the anatomical relationship between the MAL and the celiac trunk. In contrast to available literature which says the average MAL thickness of > 4mm is an indicator of increased thickness, we observed much higher average thickness in the studied population. The findings contribute to a better understanding of normal anatomical variations which can serve as reference values for accurate radiological diagnosis of MALS. The histological examination revealed the heterogeneous nature of the MAL tissue composition, suggesting variable mechanical properties and functions in different regions.

Rogue AI: Cautionary Cases in Neuroradiology and What We Can Learn From Them.

Introduction In recent years, artificial intelligence (AI) in medical imaging has undergone unprecedented innovation and advancement, sparking a revolutionary transformation in healthcare. The field of radiology is particularly implicated, as clinical radiologists are expected to interpret an ever-increasing number of complex cases in record time. Machine learning software purchased by our institution is expected to help our radiologists come to a more prompt diagnosis by delivering point-of-care quantitative analysis of suspicious findings and streamlining clinical workflow. This paper explores AI's impact on neuroradiology, an area accounting for a substantial portion of recent radiology studies. We present a case series evaluating an AI software's performance in detecting neurovascular findings, highlighting five cases where AI interpretations differed from radiologists' assessments. Our study underscores common pitfalls of AI in the context of CT head angiograms, aiming to guide future AI algorithms. Methods We conducted a retrospective case series study at Stony Brook University Hospital, a large medical center in Stony Brook, New York, spanning from October 1, 2021 to December 31, 2021, analyzing 140 randomly sampled CT angiograms using AI software. This software assessed various neurovascular parameters, and AI findings were compared with neuroradiologists' interpretations. Five cases with divergent interpretations were selected for detailed analysis. Results Five representative cases in which AI findings were discordant with radiologists' interpretations are presented with diagnoses including diffuse anoxic ischemic injury, cortical laminar necrosis, colloid cyst, right superficial temporal artery-to-middle cerebral artery(STA-MCA) bypass, and subacute bilateral subdural hematomas. Discussion The errors identified in our case series expose AI's limitations in radiology. Our case series reveals that AI's incorrect interpretations can stem from complexities in pathology, challenges in distinguishing densities, inability to identify artifacts, identifying post-surgical changes in normal anatomy, sensitivity limitations, and insufficient pattern recognition. AI's potential for improvement lies in refining its algorithms to effectively recognize and differentiate pathologies. Incorporating more diverse training datasets, multimodal data, deep-reinforcement learning, clinical context, and real-time learning capabilities are some ways to improve AI's performance in the field of radiology. Conclusion Overall, it is apparent that AI applications in radiology have much room for improvement before becoming more widely integrated into clinical workflows. While AI demonstrates remarkable potential to aid in diagnosis and streamline workflows, our case series highlights common pitfalls that underscore the need for continuous improvement. By refining algorithms, incorporating diverse datasets, embracing multimodal information, and leveraging innovative machine learning strategies, AI's diagnostic accuracy can be significantly improved.

Myocardial perfusion in patients with diabetes mellitus according to stress CMR with adenosine triphosphate

Aim. To evaluate the features of myocardial perfusion according to stress CMR with adenosine triphosphate (ATP) in patients with type 2 diabetes mellitus (DM) and obstructive and non-obstructive coronary arteries (CA).Materials and Methods. Stress СMR with ATP was provided in 55 patients with a suspected or known ischemic heart disease. 39 patients of them had DM type 2. All patients were provided with invasive coronary angiography or non-invasive CT angiogram to evaluate lesions of CA. Study protocol included providing myocardial perfusion in a rest and stress with ATP in dose 160 mkg/ kg/min during 3-6 min.Results. The detection of stress-induced perfusion defects was statistically significantly associated with the obstructive CA lesions of more than 50% (p&lt;0,001). With non-obstructive CA lesions less than 50%, perfusion defects were found more often in patients with DM (36.4%) than in patients without DM (16.7%). Furthermore, the detection of stress-induced myocardial ischemia of patients with DM was not statistically significantly associated with obstructive CA (p=0,071) In case of positive result of stress CMR, patients with DM had a more widespread zone of stress-induced ischemia in the form of increase involved segments (6,45±3,78 (4,78-8,13) than patients without DM (3,17±1,60 (1,49-4,85), p=0,050).Conclusion. Patients with DM and non-obstructive CA are more likely to have a myocardial perfusion disorder than patients without DM due to coronary microvascular dysfunction.

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.

An Enigmatic Discovery - Accidental Insertion of Internal Jugular Haemodialysis Catheter into the Vertebral Vein

A 40-year-old male was admitted to the medical ward with chronic kidney disease with uremic symptoms and a decision was made to initiate the patient on haemodialysis. It was decided to catheterize the right internal jugular vein directly as the patient would require an A-V fistula in the near future which would be created in the left arm subsequently.&#x0D; Procedure&#x0D; During the time of right internal jugular vein catheterization using the anterior landmark technique, the right carotid artery was punctured leading to hematoma formation on the right side of the neck, despite adequate haemostatic measures.&#x0D; It was decided to catheterize the left internal jugular vein subsequently. Using the anterior landmark technique again, venipuncture was performed on the left side of the neck and in the first attempt itself the guide wire was inserted without any difficulty or resistance.&#x0D; Safe back-flow of venous blood was achieved through all ports of the catheter; that is, the catheter tip was presumed to be well positioned in the left internal jugular vein (IJV), as seen on the chest X-ray taken following the procedure.&#x0D; Clinical Course&#x0D; The patient complained of numbness over the left shoulder and weakness of the left upper limb following the procedure and was evaluated for the same. Under the clinical suspicion of left vertebral artery catheterization, a vascular surgeon opinion was sought and a CT angiogram of the neck was advised.&#x0D; The CT angiogram revealed the catheter entering the left vertebral vein at the level of C6 vertebra, coursing anteroinferiorly reaching the left brachiocephalic vein with its tip noted at the confluence of subclavian vein with internal jugular vein.&#x0D; After the CT angiogram, the misplaced catheter was promptly extracted to prevent the onset of additional complications.&#x0D; No excessive resistance was encountered during the catheter removal, and there were no signs of hematoma formation.&#x0D; Over the next few days, the patient’s symptoms of numbness and weakness resolved spontaneously.&#x0D; The patient had no neurological complaints and deficits on examination during follow-up in the outpatient department.

Incidence, presentation and outcome of acute aortic dissection: results from a population-based study

ObjectivesTo describe the incidence of acute aortic dissection in a clearly defined population, to assess onset symptoms and admission biochemical marker levels and to analyse variables potentially associated to mortality.MethodsMedical...

Denoising Multiphase Functional Cardiac CT Angiography Using Deep Learning and Synthetic Data.

Coronary CT angiography is increasingly used for cardiac diagnosis. Dose modulation techniques can reduce radiation dose, but resulting functional images are noisy and challenging for functional analysis. This retrospective study describes and evaluates a deep learning method for denoising functional cardiac imaging, taking advantage of multiphase information in a three-dimensional convolutional neural network. Coronary CT angiograms (n = 566) were used to derive synthetic data for training. Deep learning-based image denoising was compared with unprocessed images and a standard noise reduction algorithm (block-matching and three-dimensional filtering [BM3D]). Noise and signal-to-noise ratio measurements, as well as expert evaluation of image quality, were performed. To validate the use of the denoised images for cardiac quantification, threshold-based segmentation was performed, and results were compared with manual measurements on unprocessed images. Deep learning-based denoised images showed significantly improved noise compared with standard denoising-based images (SD of left ventricular blood pool, 20.3 HU ± 42.5 [SD] vs 33.4 HU ± 39.8 for deep learning-based image denoising vs BM3D; P < .0001). Expert evaluations of image quality were significantly higher in deep learning-based denoised images compared with standard denoising. Semiautomatic left ventricular size measurements on deep learning-based denoised images showed excellent correlation with expert quantification on unprocessed images (intraclass correlation coefficient, 0.97). Deep learning-based denoising using a three-dimensional approach resulted in excellent denoising performance and facilitated valid automatic processing of cardiac functional imaging. Keywords: Cardiac CT Angiography, Deep Learning, Image Denoising Supplemental material is available for this article. © RSNA, 2024.

Superior laryngeal artery originating from the lingual artery.

In most cases, the superior laryngeal artery (SLA) branches from the superior thyroid artery, which, in turn, leaves the external carotid artery. Few dissection studies found previously that the SLA could originate from the lingual artery. We report here probably the first evidence of such a rare anatomical variation found unilaterally in a retrospectively evaluated by computed tomography angiography adult male case. The left SLA left a suprahyoid coil of the lingual artery and continued over the greater hyoid horn to enter the larynx through the thyrohyoid membrane. On both sides, thyroid foramina were found, but only the right one used for the entry of the right SLA. Therefore, the rare SLA origin from the lingual artery can be documented on computed tomography angiograms, which could help during preoperative evaluations and prevent unwanted surgical complications.

Assessment of the Length of the Pedicle of the Anterolateral Thigh Flap.

Purpose To estimate the length of the pedicle of the anterolateral thigh flap (ALT) and to assess how this length corresponds with the distances between the anatomical landmarks. Methods The study group consisted of patients who underwent computed tomography angiograms ranging minimally from the anterior superior iliac spine (ASIS) superiorly and tibia inferiorly. In the study we included 44 patients. In the axial window we identified single scans with (1) ASIS, (2) the apex of the greater trochanter, (3) the origin of the descending branch of the lateral femoral circumflex artery (LFCA), (4) the superolateral corner of the patella, (5) knee joint gap.Knowing the slice thickness in every patient and the difference in scan number we measured(A)-the distance between the scan (1) and the scan (4). This distance (A) represented the length of the line connecting ASIS and the superolateral corner of the patella (AP line). Next, we identified (6) the midpoint of the distance (A). Next we measured (B)-the distance between the scan (2) and the scan (5) and (C)-the distance between the scan (3) andthe midpoint of the AP line (6). Results Mean distances between the scans were: (A) 45.34 cm (SD=4.14), (B) 43.12 cm (SD=4.08), (C) 11.69 cm (SD=1.62). There was low positive correlation between the distance (A) and the distance (C) (rs=0.43) and moderate positive correlation between the distance (B) and the distance (C) (rs=0.53). Conclusion Our study suggests that the mean estimated length of the ALT flap pedicle is11.69 cm and that it positively correlates with the length of the femur and the length of the AP line.

Nonaneurysmal perimesencephalic subarachnoid hemorrhage on noncontrast head CT: An accuracy, inter-rater, and intra-rater reliability study

Background and purposeTo evaluate the reliability and accuracy of nonaneurysmal perimesencephalic subarachnoid hemorrhage (NAPSAH) on Noncontrast Head CT (NCCT) between numerous raters. Materials and methods45 NCCT of adult patients with SAH who also had a catheter angiography (CA) were independently evaluated by 48 diverse raters; 45 raters performed a second assessment one month later. For each case, raters were asked: 1) whether they judged the bleeding pattern to be perimesencephalic; 2) whether there was blood anterior to brainstem; 3) complete filling of the anterior interhemispheric fissure (AIF); 4) extension to the lateral part of the sylvian fissure (LSF); 5) frank intraventricular hemorrhage; 6) whether in the hypothetical presence of a negative CT angiogram they would still recommend CA. An automatic NAPSAH diagnosis was also generated by combining responses to questions 2–5. Reliability was estimated using Gwet's AC1 (κG), and the relationship between the NCCT diagnosis of NAPSAH and the recommendation to perform CA using Cramer's V test. Multi-rater accuracy of NCCT in predicting negative CA was explored. ResultsInter-rater reliability for the presence of NAPSAH was moderate (κG = 0.58; 95%CI: 0.47, 0.69), but improved to substantial when automatically generated (κG = 0.70; 95%CI: 0.59, 0.81). The most reliable criteria were the absence of AIF filling (κG = 0.79) and extension to LSF (κG = 0.79). Mean intra-rater reliability was substantial (κG = 0.65). NAPSAH weakly correlated with CA decision (V = 0.50). Mean sensitivity and specificity were 58% (95%CI: 44%, 71%) and 83 % (95%CI: 72 %, 94%), respectively. ConclusionNAPSAH remains a diagnosis of exclusion. The NCCT diagnosis was moderately reliable and its impact on clinical decisions modest.

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.

The Diversity of the Linguofacial Trunk.

Background and Objectives: Typically, the external carotid artery (ECA) sends off separate anterior branches: the superior thyroid, lingual, and facial arteries. These could, however, form common trunks: thyrolinguofacial, linguofacial (LFT), or thyrolingual. Although known, the LFT variant was poorly detailed previously, and most authors just counted the variant. We aimed to demonstrate the individual anatomical possibilities of the LFT on a case-by-case basis. Materials and Methods: 150 archived angioCT files were used. After applying inclusion and exclusion criteria, 147 files of 86 males and 61 females were kept for this study. Results: In 34/147 cases, LFTs were found (23.12%). Bilateral LFTs were found in 13/34 cases (38.24%) and unilateral LFTs in 21/34 (61.76%) cases. Forty-seven LFTs were thus identified and further studied for different variables. Regarding the vertical topography of LFT origin, type 1a (suprahyoid and infragonial) was found in 28 LFTs (59.57%), type 1b (suprahyoid and gonial) was found in eight LFTs (17.02%), type 3 (suprahyoid and supragonial) was found in two LFTs (4.25%), type 2 (hyoid level of origin) in eight LFTs (17.02%), and type 3 (infrahyoid origin) in just one LFT (2.12%). Types of the initial course of the LFT were determined: type I, ascending, was found in 22/47 LFTs; type II, descending, in 12/47 LFTs; and type III, transverse, in 13/47 LFTs. Regarding the orientation of the first loop of the LFT, 23/47 LFTs had no loop, 4/47 had anterior loops, 1/47 had a posterior loop, 5/47 had superior loops, 5/47 had inferior loops, and 9/47 had medial loops. The position of the LFT relative to the ECA was classified as medial, anterior, or antero-medial. An amount of 12/47 LFTs were anterior to the ECA, 22/47 were antero-medial, 10/47 were medial, 2/47 were inferior, and 1/47 was lateral. Regarding their general morphology, 23/47 LFTs had a rectilinear course, 22/47 had loops, and 2/47 were coiled. A case-by-case presentation of results further demonstrated the diversity of the LFT. Conclusions: In conclusion, the morphology and topography of the LFT are individually specific and unpredictable. It can be anticipated case-by-case by surgeons on CT or MR angiograms.

Neurological Improvement by One-Thirds Is Associated With Early Recanalization in Stroke With Large Vessel Occlusion.

A proportion of large vessel occlusion strokes demonstrate early recanalization, obviating the initial intention to proceed to endovascular thrombectomy. Neurological improvement is a possible surrogate marker for reperfusion. We aimed to determine the optimal threshold of neurological improvement, as defined by the National Institutes of Health Stroke Scale (NIHSS), which best associates with early recanalization. We retrospectively analyzed consecutive patients with large vessel occlusion transferred from primary stroke centers to a tertiary comprehensive stroke center in Melbourne, Australia, for possible endovascular thrombectomy from January 2018 to December 2022. Absolute and percentage changes in NIHSS between transfer, as well as other definitions of neurological improvement, were compared using receiver operating characteristic curve analysis for association with recanalization as defined by the absence of occlusion in the internal carotid artery, middle cerebral artery (M1 or M2 segments), or basilar artery on repeat vascular imaging. Six hundred and fifty-four transferred patients with large vessel occlusion were included in the analysis: mean age was 68.8±14.0 years, 301 (46.0%) were women, and 338 (52%) received intravenous thrombolytics. The proportion of extracranial internal carotid artery, intracranial internal carotid artery, M1, proximal M2, and basilar artery occlusion was 18.8%, 13.6%, 48.3%, 15.0%, and 4.3%, respectively, on initial computed tomography angiogram. Median NIHSSprimary stroke center and NIHSScomprehensive stroke center scores were 15 (interquartile range, 9-18) and 13 (interquartile range, 8-19), respectively. Early recanalization occurred in 82 (13%) patients. NIHSS reduction of ≥33% was the best tradeoff between sensitivity (64%) and specificity (83%) for identifying recanalization. NIHSS reduction of ≥33% had the highest discriminative ability to predict recanalization (area under the curve, 0.735) in comparison with other definitions of neurological improvement. One-third neurological improvement between the primary hospital and tertiary center was the best predictor of early recanalization.