Afferent Artery Research Articles

Relationship between Circle of Willis Variations and Cerebral or Cervical Arteries Stenosis Investigated by Computer Tomography Angiography and Multitask Convolutional Neural Network.

Circle of Willis (CoW) is the most critical collateral pathway that supports the redistribution of blood supply in the brain. The variation of CoW is closely correlated with cerebral hemodynamic and cerebral vessel-related diseases. But what is responsible for CoW variation remains unclear. Moreover, the visual evaluation for CoW variation is highly time-consuming. In the present study, based on the computer tomography angiography (CTA) dataset from 255 patients, the correlation between the CoW variations with age, gender, and cerebral or cervical artery stenosis was investigated. A multitask convolutional neural network (CNN) was used to segment cerebral arteries automatically. The results showed the prevalence of variation of the anterior communicating artery (Aco) was higher in the normal senior group than in the normal young group and in females than in males. The changes in the prevalence of variations of individual segments were not demonstrated in the population with stenosis of the afferent and efferent arteries, so the critical factors for variation are related to genetic or physiological factors rather than pathological lesions. Using the multitask CNN model, complete cerebral and cervical arteries could be segmented and reconstructed in 120 seconds, and an average Dice coefficient of 78.2% was achieved. The segmentation accuracy for precommunicating part of anterior cerebral artery and posterior cerebral artery, the posterior communicating arteries, and Aco in CoW was 100%, 99.2%, 94%, and 69%, respectively. Artificial intelligence (AI) can be considered as an adjunct tool for detecting the CoW, particularly related to reducing workload and improving the accuracy of the visual evaluation. The study will serve as a basis for the following research to determine an individual's risk of stroke with the aid of AI.

Dissecting Fusiform PICA Aneurysm Repair With Trapping and an Unconventional End-to-Side Reanastomosis: 2-Dimensional Operative Video.

Dissecting fusiform posterior inferior cerebellar artery (PICA) aneurysms are rare and challenging.1,2 One common treatment is occlusion of the aneurysm and parent artery via an endovascular approach without revascularization.3 Revascularization of the artery requires an open microsurgical bypass or endovascular placement of a newer-generation flow diverter.4 We present an end-to-side reanastomosis of the PICA for treatment of a dissecting fusiform left PICA aneurysm with anatomy deemed unfavorable for endovascular treatment in a 62-yr-old man with subarachnoid hemorrhage. After discussions regarding risks, benefits, and alternatives to the procedure, the family consented to surgical treatment. A far-lateral craniotomy was performed, with partial condylectomy to widen the exposure. The cisterna magna was opened, and the dentate ligament was cut to visualize the vertebral artery. The PICA was identified and traced distally to the aneurysmal segment, which was circumferentially diseased. Perforators were noted immediately distal to the aneurysm. The aneurysm was then trapped, and the afferent artery was transected and brought to the sidewall of the distal artery. The recipient site was trapped with temporary clips, and a linear arteriotomy was made. An end-to-side reanastomosis was performed, temporary clips were removed, and hemostasis was achieved. Postoperative angiography confirmed bypass patency and preservation of the PICA perforators. Conventional reanastomosis of the parent artery after aneurysm excision is achieved by end-to-end reanastomosis. In contrast, we performed an unconventional end-to-side reanastomosis to revascularize the PICA while leaving the efferent artery in situ to protect its medullary perforators. This bypass is an example of a fourth-generation bypass.5,6 Used with permission from the Barrow Neurological Institute, Phoenix, Arizona.

Vascularization of the uncus - Anatomical study and clinical implications.

Background: The objective of this paper was to describe the arterial supply of the uncus and quantify the branches directed to the anteromedial aspect of the human temporal cortex.Methods: We studied 150 human cerebral hemispheres identifying main afferent arteries supplying the anteromedial temporal cortex with particular attention to the uncus, determining the territory supplied by each artery through either cortical or perforating branches.Results: The uncus was supplied by 419 branches of the anterior choroidal artery (AChA), 210 branches of the internal carotid artery (ICA), 353 branches of the middle cerebral artery (MCA), and 122 branches of the posterior cerebral artery (PCA). The total of supplying vessels was 1104 among the 150 hemispheres studied, which corresponds to 7.36 arteries per uncus. The average of branches per hemisphere was as follows: 2.79 from AChA, 1.40 from ICA, 2.35 from MCA, and 0.81 from PCA. The relative contribution of each artery for the total of specimens studied was as follows: 38% from AChA, 19% from ICA, 32% from the MCA, and 11% from the PCA. We identified cortical anastomoses mostly between the MCA and PCA (27 cases).Conclusion: We described and quantified the uncus’ vascularization, including anatomical variations. This updated, detailed description of the mesial temporal vascularization is paramount to improve the treatment of neurosurgical conditions.

Blood Flow and Shear Stress Allow Monitoring of Progression and Prognosis of Tumor Diseases

In the presence of tumor angiogenesis, blood flow must increase, leading to an elevation of blood flow velocities (BFVels) and wall shear stress (WSS) in upstream native arteries. An adaptive arterial remodeling is stimulated, whose purpose lies in the enlargement of the arterial inner diameter, aiming for normalization of BFVels and WSS. Remodeling engages delayed processes that are efficient only several weeks/months after initiation, independent from those governing expansion of the neovascular network. Therefore, during tumor expansion, there is a time interval during which elevation of BFVels and WSS could reflect disease progression. Conversely, during the period of stability, BFVels and WSS drop back to normal values due to the achievement of remodeling processes. Ovarian peritoneal carcinomatosis (OPC), pseudomyxoma peritonei (PMP), and superficial arteriovenous malformations (AVMs) are diseases characterized by the development of abnormal vascular networks developed on native ones. In OPC and PMP, preoperative blood flow in the superior mesenteric artery (SMA) correlated with the per-operative peritoneal carcinomatosis index (OPC: n = 21, R = 0.79, p < 0.0001, PMP: n = 66, R = 0.63, p < 0.0001). Moreover, 1 year after surgery, WSS in the SMA helped in distinguishing patients with PMP from those without disease progression [ROC-curve analysis, AUC = 0.978 (0.902–0.999), p < 0.0001, sensitivity: 100.0%, specificity: 93.5%, cutoff: 12.1 dynes/cm2]. Similarly, WSS in the ipsilateral afferent arteries close to the lesion distinguished stable from progressive AVM [ROC-curve analysis, AUC: 0.988, (0.919–1.000), p < 0.0001, sensitivity: 93.5%, specificity: 95.7%; cutoff: 26.5 dynes/cm2]. Blood flow volume is indicative of the tumor burden in OPC and PMP, and WSS represents an early sensitive and specific vascular marker of disease progression in PMP and AVM.

Is fetuin-A a biomarker of dialysis access dysfunction?

The arteriovenous (AV) access function of hemodialysis (HD) patients can be impaired by afferent artery stiffness due to preexisting microcalcification and by venous stenosis secondary to neointimal hyperplasia in whose development participates an upregulated local inflammatory process. Fetuin-A is a circulating potent inhibitor of vascular calcification and plays an important anti-inflammatory role. The aims of this prospective study were to investigate the relationship between baseline serum fetuin-A levels and: blood flow (QA) values at baseline, AV access failure (thrombosis or intervention for stenosis) during follow-up and primary unassisted AV access patency. We measured baseline serum fetuin-A levels and QA values of the AV access in 64 HD patients under routine QA surveillance for stenosis. Patients were classified into tertiles according to their baseline fetuin-A levels (g/L): <0.5 (tertile-1), 0.5-1.20 (tertile-2), and >1.20 (tertile-3). Fetuin-A was positively correlated with QA (Spearman coefficient = 0.311, p = 0.012). Fourteen patients (21.9%) underwent AV access failure and they had lower fetuin-A (0.59 ± 0.32 g/L) and lower QA (739.4 ± 438.8 mL/min) values at baseline compared with the remaining patients (1.05 ± 0.65 g/L and 1273.0 ± 596.3 mL/min, respectively) (p = 0.027 and p < 0.001, respectively). The AV access failure rate was highest (34.8%) in tertile-1 (lowest fetuin-A level). Unadjusted Cox regression analysis showed a decrease in the risk of AV access patency loss by increasing fetuin-A concentration (hazard ratio 0.395 (95% confidence interval: 1.42-1.69), p = 0.044) but it was not confirmed in the adjusted model, although the hazard ratio was low (0.523). Kaplan-Meier analysis showed that patients in tertile-3 (highest fetuin-A concentration) had the highest primary unassisted AV access patency (λ2 = 4.68, p = 0.030, log-rank test). If our results are confirmed in further studies, fetuin-A could be used as a circulating biomarker to identify HD patients at greater risk for AV access dysfunction, who would benefit from much closer dialysis access surveillance.

Massive haemorrhagic complications of ruptured pulmonary arteriovenous malformations: outcomes from a 12\xa0years\u2019 retrospective study

BackgroundThe life-threatening haemorrhagic complications of pulmonary arteriovenous malformations (PAVMs) are extremely rare, and only described in isolated cases. This study was designed to comprehensively investigate management of ruptured PAVMs.MethodsWe retrospectively assessed clinical and imaging data of ruptured PAVMs to summarize incidence, clinical characteristics, and outcomes following embolisation between January 2008 and January 2021.ResultsEighteen of 406 (4.4%) patients with PAVMs developed haemorrhagic complications. Twelve of 18 patients were clinically diagnosed with hereditary haemorrhagic telangiectasia (HHT). Haemorrhagic complications occurred with no clear trigger in all cases. Eight of 18 patients (44.4%) were initially misdiagnosed or had undergone early ineffective treatment. 28 lesions were detected, with 89.3% of them located in peripheral lung. Computed tomography angiography (CTA) showed indirect signs to indicate ruptured PAVMs in all cases. Lower haemoglobin concentrations were associated with the diameter of afferent arteries in the ruptured lesions. Successful embolotherapy was achieved in all cases. After embolotherapy, arterial oxygen saturation improved and bleeding was controlled (P < 0.05). The mean follow-up time was 3.2 ± 2.5 years (range, 7 months to 10 years).ConclusionsLife threatening haemorrhagic complications of PAVMs are rare, they usually occur without a trigger and can be easily misdiagnosed. HHT and larger size of afferent arteries are major risk factors of these complications. CTA is a useful tool for diagnosis and therapeutic guidance for ruptured PAVMs. Embolotherapy is an effective therapy for this life-threatening complication.

Pseudoaneurysma van de arteria hepatica sinistra bij een patiënt met chronische pancreatitis gecompliceerd met obstructieve icterus

Pseudoaneurysm of the left hepatic artery in a patient with chronic pancreatitis complicated with obstructive jaundice. A pseudoaneurysm of the left hepatic artery that causes an obstructive jaundice is a rare entity that has only been described a few times in scientific literature. We describe the case of a patient with a giant pseudoaneurysm (10 cm diameter) caused by chronic pancreatitis, that compresses the choledochus duct. The diagnosis was made by CT scan (computed tomography). The treatment consisted of a ligation of the afferent and efferent artery and evacuation of the aneurysmatic mass. A persisting bile leak was caused by a haemobiliary fistula between the aneurysmatic sac and choledochus duct. Therefore, a hepaticojejunostomy was performed with a delay of 4 weeks. The patient recovered after a few weeks and left the hospital in a good condition.

The ablation of thyroid nodule’s afferent arteries before radiofrequency ablation: preliminary data.

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Raynaud's Phenomenon: A Vascular Acrosyndrome That Requires Long-Term Care.

Some 5-10% of the German population are affected by Raynaud's phenomenon (RP). In around 10-20% of cases RP arises from an underlying disease, most commonly a connective tissue disease. This review encompasses the diagnosis and differential diagnosis of RP and examines the efficacy of the currently available pharmaceutical and non-pharmaceutical treatment options. We conducted a selective literature search in PubMed using the search terms "Raynaud's phenomenon", "Raynaud's syndrome," "vasospasm," "vascular acrosyndrome," and "systemic sclerosis," together with a search of the Cochrane Database of Systematic Reviews up to April 2020. Raynaud's phenomenon mainly affects the fingers or toes and is typically triggered by cold or emotional stressors. The most important diagnostic steps are demonstration of a tendency towards digital vasospasm, exclusion of occlusions in the afferent arteries and acral vessels, nail-fold capillaroscopy, and determination of autoantibody status. Tumor screening should be arranged in the presence of B symptoms or first manifestation of RP in old age. The onset of RP in childhood is a rare occurrence and points to a secondary origin. The principal options for treatment are protection against cold and administration of calcium antagonists, which reduces the occurrence of RP by around 20-40 %. The treatment of RP in patients with systemic sclerosis is described in the recommendations of the European League Against Rheumatism (EULAR). At onset or after years of latency, patients with Raynaud phenomenon may have an underlying disease (most commonly a connective tissue disease). Long-term specialist care is necessary for asymptomatic patients with risk factors and for those with clinically manifest symptoms of an underlying condition alike.

Evaluation of perfusion changes using a 2D Parametric Parenchymal Blood Flow technique with automated vessel suppression following partial spleen embolization in patients with hypersplenism and portal hypertension.

To evaluate the feasibility and potential value of 2D Parametric Parenchymal Blood Flow (2D-PPBF) for the assessment of perfusion changes following partial spleen embolization (PSE) in a retrospective observational study design.Overall, 12 PSE procedures in 12 patients were included in this study. The outcome of the study was the platelet response (PR), calculated as the percentage increase of platelet count (PLT), following PSE. To quantify perfusion changes using 2D-PPBF, the acquired digital subtraction angiography series were post-processed. A reference region-of-interest (ROI) was placed in the afferent splenic artery and a target ROI was positioned on the embolization territory of the spleen on digital subtraction angiography series pre- and post-embolization. The ratios of the target ROIs to the reference ROIs were calculated for the Wash-In-Rate (WIR), the Time-To-Peak (TTP) and the Area-Under-the-Curve (AUC). Comparisons between pre- and post-embolization data were made using Wilcoxon signed-rank test and Spearman's rank correlation coefficient (r). Afterwards, the study population was divided by the median of the TTP before PSE to analyze its value for the prediction of PR following PSE.Following PSE, PLT increased significantly from 43,000 ± 21,405 platelets/μL to 128,500 ± 66,083 platelets/μL with a PR of 255 ± 243% (P = .003). In the embolized splenic territory, the pre-/post-embolization 2D-PPBF parameter changed significantly: WIRpre-PSE 1.23 ± 2.42/WIRpost-PSE 0.09 ± 0.07; -64 ± 46% (p = 0.04), TTPpre-PSE 4.41 ± 0.99/TTPpost-PSE 5.67 ± 1.52 (P = .041); +34 ± 47% and AUCpost-PSE 0.81 ± 0.85/AUCpost-PSE 0.14 ± 0.08; -71 ± 18% (P = .002). A significant correlation of a 2D-PPBF parameter with the PLT was found for TTPpre-PSE/PLTpre-PSE r = -0.66 (P = .01). Subgroup analysis showed a significantly increased PR for the group with TTPpre-PSE >4.44 compared to the group with TTPpre-PSE ≤4.44 (404 ± 267% versus 107 ± 76%; P = .04).2D-PPBF is an objective approach to analyze the perfusion reduction of embolized splenic tissue. TTP derived from 2D-PPBF has the potential to predict the extent of PR during PSE.

Collateral flow at circle of Willis in healthy condition.

Experimental simulation of cerebrovascular system would be very beneficial tool to evaluate millions of human body cascade sequence. The Circle of Willis (CoW) recently named Cerebral Arterial Circle (CAC) is a main loop structure of cerebral circulatory system which positioned at the cranium base. In this research, we investigate cerebral artery flow pattern in cerebral arteries including afferent, Willisian, and efferent arteries of CAC emphasizing on communicating and connecting arteries which are main routes in CAC and as a risky sites when autoregulation is occurred in terminal parts of middle cerebral arteries (MCAs) by PMMA (Polymethyl methacrylate) chip and high quality camera which depict Sequential images. This novelty study analyze flow pattern in CAC that have been challenging subject area for many years which have investigated by scientists yet, because flow pattern in CAC indicate complication progression. This research tries to construct new platform in cerebral circulation analyzing method by reliable experimental in-vitro approach. The outcomes of this study demonstrate that communicating arteries especially anterior communicating artery (ACoA) is main artery in CAC flow distribution.

The Ablation of Thyroid Nodule's Afferent Arteries Before Radiofrequency Ablation: Preliminary Data.

Induced radiofrequency thermal ablation is the cytoreductive treatment of symptomatic benign thyroid nodules, metastatic and recurrent thyroid tumors and papillary thyroid microcarcinomas. It is a safe and effective alternative to surgery and it allows to obtain satisfactory results in terms of volumetric reduction of the nodule with significant improvement in the quality of life. The trans-isthmic approach and the moving shot technique are the two basic techniques; however, an advanced technique, artery-first feeding radiofrequency ablation, has been developed and validated. We have prospectively included 29 consecutive patients who have undergone radiofrequency ablation (Group A) or artery- first vRFA (Group B). All included patients had a diagnosis of benign nodular goiter and they underwent a single session of radiofrequency ablation. All patients followed a follow-up program at 1 month, 3 months, and 6 months. Continuous variables (age, TSH value, basal volume of nodule, used Joule, time in second of the procedure, nodules’ volume at 1-, 3-, and 6- months of follow-up and percentage of volume reduction at 1-, 3-, and 6- months of follow-up) were described as mean, standard deviation and range, while categorical variables (gender, nodule structure and nodule vascularization) were described as number of cases and percentage. Independent samples t-test were performed to compare the continuous variables. A Test of Proportions was applied to the categorical variables. The Fisher’s exact test was used to analyze the gender. Statistical significance was considered in case of p-value <0.05. Solid structure and spongiform structure showed statistic differences with p-values of 0.022 and 0.023 respectively between two groups. The percentage of reduction at 1 month did not show a significant difference between two groups; instead, the percentage of volume reduction was decreased mostly in the Group B at 3 months and 6 months of follow-up with a p-value of 0.003 and 0.013, respectively. The Joules/energy used showed a statistically significant difference (p-value=0.05), more energy must be used in vascular radiofrequency ablation. These data allow us to hypothesize that vRFA may improve the effectiveness of the procedure, allowing for a reduction in volume more quickly. They were preliminary but promising results, clearly a larger series of cases and prolonged follow-up are needed to clarify and confirm our observations.

Renal Denervation in Hypertension.

The column in this issue is supplied by Drs. Benjamin Lee, MD, and Usman Ansari, DO. Dr. Lee is an assistant professor of clinical medicine at the Houston Methodist Institute for Academic Medicine and Weill Cornell Medical College. After earning his medical degree at Harvard Medical School, Dr. Lee completed a residency in internal medicine and a nephrology fellowship at the University of California San Francisco (UCSF) while simultaneously obtaining a master of advanced study in clinical research from the UCSF departments of Epidemiology and Biostatistics. He maintains his clinical practice with the Houston Kidney Consultants. Dr. Ansari earned a Doctor of Osteopathy from Touro University College of Osteopathic Medicine in California and is completing his internal medicine residency at Houston Methodist.

Combined surgical treatment of arteriovenous malformation of the lower jaw

The objective – to presents the observation of combined treatment of a patient with arteriovenous malformation of the lower jaw.A man, 21 years old, was hospitalized in the Scientific-Practical Center of Endovascular Neuroradiology NAMS of Ukraine with complaints of bleeding from a tooth socket after an attempt to remove the 6th tooth (first painter) of the lower jaw on the left. According to the performed survey radiography of the lower jaw, an aneurysmal bone cyst was revealed in the body of the lower jaw on the left, corresponding to the localization of bleeding. According to cerebral angiography, an arteriovenous malformation of the lower jaw was revealed on the left, the afferent arteries of which were: the right facial artery (a branch of the right external carotid artery (ECA)), the left facial artery (a branch of the left ECA), the lower alveolar artery, the superior-posterior alveolar artery (branches of the maxillary artery ‒ the terminal branch of the left ECA) with drainage into a vein, which was located in the body of the lower jaw. In order to exclude the malformation from the bloodstream and prevent bleeding, a controlled embolization of the malformation was performed using non-spherical emboli – polyvinyl alcohol (PVA) particles from Cook, USA. Using a transfemoral approach, a guide catheter was inserted into the orifice of the ECA, then a Headway 27 microcatheter (Microvention, USA) was passed through it along a Traxes 14 guide wire (Microvention, USA), the afferent arteries of the malformation were selectively cathete-rized in turn, and embolization was performed after superselective angiography. The patient was discharged in a satisfactory condition. Two weeks after the operation, the bleeding resumed. The performed control cerebral angiography revealed a relapse of the malformation with a change in its angioarchitectonics ‒ the filling of the malformation in the late arterial and venous phases of cerebral blood flow was noted. Re-embolization was performed using PVA emboli (Cook), which was supplemented by transcutaneous puncture of the drainage vein in the mandible and its embolization with histoacryl (B. Braun, Germany) and lipiodol (Guerbet, France) in a 1 : 1 ratio. Results. As a result of using this technique, it was possible to turn off the malformation completely. For 6 months from the moment of surgery, no bleeding was noted, and subsequently the patient had a tooth removed without complications.Conclusions. The proposed method for treating arteriovenous malformation of the lower jaw, proposed in this case, showed the effectiveness of a combination of endovascular embolization in combination with transcutaneous embolization of the draining vein and can be successfully used to treat this pathology.

Autophagy in diabetic nephropathy: a review.

Diabetes mellitus (DM) is the leading cause of end stage renal disease. 40% of the patients worldwide will require replacement therapy after 20years of DM worldwide. Early-stage diabetic nephropathy is characterized by hyperfiltration related to hypeglycemia-induced afferent artery vasodilatation with micro-and macroalbuminuria. Later on, proteinuria with arterial hypertension may appear, culminating in glomerular filtration rate (GFR) decline and end stage renal disease. Forty percent of diabetic patients develop microvascular and macrovascular complications, with increased risk among patients with genetic predisposition, such as Haptoglobin 2-2 phenotype. The most frequent complications in the daily clinical practice are diabetic kidney disease, diabetic retinopathy and vascular disease, such as coronary artery disease and stroke. Various pathways are involved in the pathogenesis of diabetic kidney disease. Chronic systemic inflammation and the inflammatory response, such as increased circulating cytokines (Interleukins), have been recognized as main players in the development and progression of diabetic kidney disease. DM is also associated with increased oxidative stress, and alterations in carbohydrate, lipid and protein metabolism. Overexpression of the renin-angiotensin-aldosterone system (RAAS) in the kidney, the vitamin D-Vitamin D receptor-klotho axis, and autophagy. Differences in the ATG5 protein levels or ATG5 gene expression involved in the autophagy process have been associated with diabetic complications such as diabetic kidney disease. Under normal blood glucose level, autophagy is an important protective mechanism in renal epithelial cells, including podocytes, proximal tubular, mesangial and endothelial cells. Down regulation of the autophagic mechanism, as in hyperglycemic condition, can contribute to the development and progression of diabetic kidney disease.

The role of emergency presentation and revascularization in aneurysms of the peripancreatic arteries secondary to celiac trunk or superior mesenteric artery occlusion

ObjectiveThe goal of this study was to analyze our 10-year experience in the treatment of aneurysms of the collateral circulation secondary to steno-occlusions of the celiac trunk (CT) or superior mesenteric artery (SMA). MethodsIn the last 10 years, 32 celiac-mesenteric aneurysms were detected (25 true aneurysms and seven pseudoaneurysms) in 25 patients with steno-occlusion of the CT or SMA. All cases were diagnosed and treated at our center, with either surgical or endovascular approach. As open surgery, we performed aneurysmectomy and revascularization; as endovascular treatment we performed both the embolization (or graft exclusion) of the aneurysm sac, and embolization of afferent and efferent arteries. ResultsSixteen patients (64%) underwent endovascular treatment, accounting for 66% of aneurysms (21/32). Six patients (24%) and seven associated aneurysms (22%) underwent open surgery. Three asymptomatic patients (12%), representing a total of four aneurysms (12%), were not treated. For endovascular procedures, the technical success rate was 90%, with a 56% clinical success rate. For open surgery, clinical and technical success were achieved in five patients (83%) and six procedures (86%), respectively. Sixty-eight percent of patients (17/25) were treated in an emergency setting, using either endovascular (88%) or open (12%) approaches. Although technical success was achieved in more than 85% of these procedures for both approaches, clinical success was reached less frequently among patients with an acute presentation (P = .041). Regardless of the type of treatment, CT or SMA revascularization during the first procedure did not show an increased rate of clinical success (P = .531). However, we reported four cases of visceral ischemia after an endovascular approach without revascularization, with three open surgical corrections required. The mean follow-up was 41 months (range, 0-136 months). ConclusionsNeither of the approaches described qualifies as a standard optimal choice. We suggest a tailored therapeutic approach based on the clinical condition at the time of diagnosis and specific vascular anatomy.

Successful endovascular treatment of extracranial arteriovenous malformation of a head: a case report

Introduction. Arteriovenous malformations (AVM) of the head represent the rare lesions that have a congenital, traumatic or post-infectious nature. In the last decade, endovascular methods have become the most prevalent in the treatment of AVM. Staged embolization is performed to achieve maximum effect and minimize the complications.Case report. A 30-year-old female patient is presented with complaints of enlarged vessels in the frontal and parietal regions. CT-angiography scan and cerebral angiography showed extracranial AVM of the fronto-parietal regions with afferent vascular supply from the right and left superficial temporal and ophtalmic arteries with significant expansion of the afferent arteries and the presence of varix dilatation of the draining veins. Two-stage endovascular embolization of AVM was performed. The first stage was embolization of the afferent vessels from the left superficial temporal artery system with exclusion of 60–65% AVM volume. Three months later, the second stage was performed with embolization of the afferent vessels from the right superficial temporal artery system and the exclusion of 75–80% of the residual volume of AVM. The non-adhesive composition SQUIDR12 (Emboflu, Switzerland) and glue composition PHILR25% (Microvention, USA) were used. A good aesthetic effect was achieved. Postoperative complications were not observed. There was no recurrence during the observation within a year.Summary. The staging and the use of various liquid embolization agents in the treatment of AVM of the head allow to achieve a good aesthetic outcome and prevent complications associated with facial soft tissue necrosis.

Shear Wave Elastography in Diagnosing Secondary Hyperparathyroidism.

This study evaluates the diagnostic value of two-dimensional shear wave elastography (2 D-SWE) technique in the evaluation of hyperplastic parathyroid glands in cases with secondary and tertiary hyperparathyroidism. A total of 59 patients (end-stage renal disease, under supplemental dialysis program) with visible parathyroid hyperplastic glands on ultrasound, confirmed by biochemical assay and scintigraphy, were enrolled; they were examined on grayscale ultrasound and 2 D shear wave elastography. We determined the elasticity index (EI) in the parathyroid gland, thyroid parenchyma and surrounding muscles, and the elasticity ratio of hyperplastic parathyroid glands compared to muscle, specifically sternocleidomastoid muscle. Patients presented fibrocystic bone disease with secondary hyperparathyroidism induced by end-stage chronic kidney disease; being on prolonged chronic dialysis therapy, they had positive sestamibi scintigraphy and high values of serum parathormone (1141.04 pg/mL). Nodules placed posterior to the thyroid capsule that were cystic, had a hypoechoic aspect, and were homogenous with an independent afferent artery were found. Mean EI in the parathyroid gland was 7.83 kPa, the median value in thyroid parenchyma was 13.76 kPa, and mean muscle EI value was 15.78 kPa. The observed mean parathyroid/muscle SWE ratio was 0.5356 and the value for parathyroid/normal thyroid parenchyma was 0.5995. Using receiver operating characteristic (ROC) analysis, we found that EI below 9.74 kPa correctly identifies parathyroid tissue, with a sensitivity of 94.8%, specificity of 90.7%, and accuracy of 92.26% when compared to normal thyroid tissue. Compared with the muscle tissue, we identified that EI below 9.98 kPa has a sensitivity, specificity, and accuracy of 93.8%, 90.7%, and 91.75%, respectively. Ultrasound elastography is a helpful tool in identifying parathyroid hyperplasia in patients with chronic kidney disease. A cutoff value of 9.98 kPa can be used in 2 D-SWE for accurate diagnosis of parathyroid disease.

The role of color Doppler ultrasonography in evaluation of hemodialysis graft dysfunction

Objective To evaluate role of duplex Doppler ultrasound in assessing arteriovenous graft (AVG) function, detecting complications and analyzing the resistance index (RI) and flow in the afferent artery. Background End-stage renal disease causes serious health problems all over the world. The numbers of patients requiring dialysis have grown. In Egypt, it is the cause of 1.3% of all deaths, with much more incidence in later years of life. A well-functioning dialysis access is the lifeline for those patients. Patients and methods This study included 20 patients (male/female: 11/9) with end-stage renal disease and on regular hemodialysis using AVG. The prospective analyses of vascular access-related data included examination of graft morphology, shunt complications, and measurement of RI and volume of blood flow at the afferent artery. Results The most common complication seen was thrombosis (53.8%). Significant relation was found between graft function and flow volume of afferent artery (P < 0.001), with mean 1011.0 ± 135.9 ml/min in functional grafts and mean 220.8 ± 202 ml/min in dysfunctional grafts. There was a highly significant relation between graft function and afferent artery RI (P < 0.005), as 57.1% of functional grafts had their RI less than 0.5, with mean of 0.45 ± 0.05; 28.6% of complicated graft had their RI more than 0.5, with mean of 0.44 ± 0.12; and all dysfunctional graft had RI more than 0.5, with mean of 0.66 ± 0.09. Conclusion Duplex sonography has high accuracy in diagnosing and assessing most hemodialysis AVG-related complications while providing us with anatomic and hemodynamic information.

The intraoperative prophylaxis of local ischemical brain damage in neurosurgical patients with cerebral aneurysm

To study the effectiveness of intraoperative administration of Cytoflavine for the prevention of ischemic brain injury during cerebral aneurysm (CA) clipping with temporary occlusion of the leading artery under general anesthesia. The prospective cohort single-center study included 40 patients with CA ( the main group - 27 patients with intraoperative administration of cytoflavine; the comparison group -13 patients without use of cytoflavine), who underwent aneurism clipping with temporary occlusion of the afferent artery. We assesed the intraoperative state of the brain, the time of awakening and extubation of patients after surgery, neurological deficit and local ischemic changes in the area of surgery according to the CT of the brain in the early postoperative period, resuscitation bed-day and the relationship of these indicators with the duration of temporary occlusion of the afferent artery in the selected groups of patients. In intergroup comparison, patients of the main group treated with intraoperative cytoflavin showed a reduction in the time of awakening (p=0.013) and the time of extubation (p=0.01) both with temporary occlusion of the afferent artery and in patients without temporary occlusion (p<0.05). The duration of resuscitation bed-day decreased in the main group of patients receiving intraoperatively cytoflavine (p=0.01), as well as in patients in the comparison group without temporary occlusion (p<0.05). Temporary occlusion of the afferent artery with short intervals of vessel occlusion in combination with intraoperative intravenous administration of cytoflavine expands the tolerability to artery occlusion in patients operated in the 'cold' period, reduces the possibility of neurological deficit, reduces the recovery period and resuscitation bed-day after surgical clipping CA.