Overview of peripheral arteriovenous malformations: From diagnosis to treatment methods

Propranolol as a potentially novel treatment of arteriovenous malformations

Vascular anomalies

Feeding and Draining Vessel Ligation with Sclerotherapy of High Flow Arteriovenous Malformations in the Head and Neck

Introduction Arteriovenous malformations (AVMs) are abnormal, direct connections between the arteries and veins. AVMs are most commonly associated with the brain and spinal cord; however, they can occur in any part of the body. Duplex ultrasound can play a pivotal role in both the diagnosis and treatment of AVMs. Methods A high-resolution duplex ultrasound machine along with a high-frequency 15–7 MHz probe was used in transcatheter techniques to treat an AVM. Ultrasound was used to guide arterial and venous access, target specific vessels for treatment, and ultimately reduce radiation exposure. Case Report A 6-year-old female patient was diagnosed with a left foot AVM and hemihypertrophy (Parkes Weber). Despite previous treatments with coil embolization, the patient developed discoloration and swelling of the left second toe and a nonhealing ulceration on the plantar aspect of the left foot. Duplex ultrasound was used to confirm the diagnosis and to aid in the treatment of the AVM. Under ultrasound guidance, catheter access was achieved via the dorsalis pedis artery and advanced distally into a large digital artery directly associated with the AVM. Anhydrous ethanol alcohol was injected through the catheter to treat the arterial inflow of the AVM. Ultrasound was then used to identify cavernous veins on the plantar aspect of the foot and to guide direct ethanol injections into the affected veins. Two weeks after the procedure, ultrasound confirmed 90% reduction in the AVM. The patient's toe discoloration resolved, and the ulceration healed. Conclusion Undiagnosed or poorly managed AVMs of the extremities can result in multiple surgical resections and skin deterioration. Ultrasound imaging of arteriovenous malformations with B-mode, color, and Doppler is essential for the evaluation (staging), treatment, and follow-up of vascular malformations. Ultrasound-guided transcatheter and direct techniques can be used in the treatment and prolonged management of AVMs. The application of ultrasound during these treatments will reduce radiation exposure in these patients.

Intracranial arteriovenous malformations (AVMs) are congenital anomalies of the blood vessels. Three traditional methods of AVMs therapy have evolved to treat AVMs: microsurgery, stereotactic radiosurgery and transarterial embolization. The principle of treatment involves eliminating the nidus, which is the source of hemorrhage, without compromising normal arterial and drainage venous of the brain. More recently, The transvenous approach in treating AVMs was popularized by successful treatment models for dural arteriovenous fistulas and peripheral vascular malformations. Although this novel technique has its challenges and perils, successful treatment of cerebral arteriovenous malformations has been reported in several centers. In this artical, we reviewed the literature of AVMs treated by transvenous endovascular approaches, and summarized the progress of this method in the treatment of AVMs. Key words: Intracranial arteriovenous malformations; Transvenous approach; Intracranial hemorrhages; Drainage venous

We are pleased to present our Research Topic, which includes a total of 10 articles, discussing the state-of-art on vascular anomalies’ research.Vascular anomalies are abnormalities or disorders of the vascular or lymphatic system, with a relatively higher prevalence in the head and neck region. According to the International Society for the Study of Vascular Anomalies (ISSVA), vascular anomalies are classified as either vascular tumors or malformations. (1) Vascular tumors can be benign, locally aggressive, or malignant; hemangioma is considered the most common type of benign vascular tumor, which is divided into infantile and congenital hemangioma; given the onset time, both are endowed with unique natural history. Other benign vascular tumors include tufted angioma, pyogenic granuloma, spindle-cell hemangioma, and intravenous lipomas, etc. When it comes to locally aggressive tumors, kaposiform hemangioendothelioma is prone to cause thrombocytopenia among affected infants and children, known as the Kasabach-Merritt phenomenon. Malignant tumors include angiosarcoma, epithelioid hemangioendothelioma, etc.Regarding vascular tumors, Verónica Fernández-Alvarez et al. contributed valuable perspectives on the intravenous lipomas of the head and neck through an up-to-date literature review and summary (https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2024.1447960/full). (2)Different from vascular tumors, vascular malformations mostly occur congenitally. In the light of the hemodynamics, vascular malformations can be sorted into low-flow (capillary malformation [CM], venous malformation [VM], and lymphatic malformation [LM]) and high-flow (arteriovenous fistula [AVF] and arteriovenous malformation [AVM]). According to ISSVA, vascular malformations are divided into the following types: simple, combined, vascular malformations of major named vessels, and vascular malformations associated with other anomalies. For low-flow vascular malformations, Sajjad Azmoun et al. (https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2024.1417788/full), (3) Han-Shu Zhang et al. (https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2024.1431723/full), (4) Zhaoyang Sun et al. (https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2024.1444896/full), (5) have introduced novel sclerosants on VMs; Weili Yuan and Xukai Wang contributed their experiences on the electrochemical therapy combined with injection of pingyangmycin treating VMs (https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2024.1425395/full). (6) Weijia Yang et al. discussed the efficacy of surgical resection, sclerotherapy, and the combination of the two in treating LMs (https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2024.1450102/full). (7) For high-flow vascular malformations, Wenliang Han et al. reported the efficacy and safety of embolization among scalp AVFs (https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2024.1461341/full). (8) Yuchen Shen et al. demonstrated the promising prognosis of peripheral AVFs after coil-assisted ethanol embolization (https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2024.1449480/full). (9) Furthermore, Lixin Su et al. shed light on the presentation and countermeasures related to the cardiopulmonary collapse induced by ethanol embolization (https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2024.1439839/abstract).(10)Thanks to the significant development of molecular genetics, our understanding of vascular malformations has gradually shifted from a macroscopic level to a microscopic one. Nowadays, gene mutations are the broadly acceptable etiology of vascular malformations and related syndromes, including somatic or germline types. For example, cutaneous or mucosal CM is considered the somatic mutation of GNAQ/GNA11; (11) common VM is caused by somatic mutation of TEK, whereas sporadic AVM results from MAP2K1 somatic mutation. (12,13) Some genetic diseases, such as hereditary hemorrhagic telangiectasia or capillary malformation-arteriovenous malformation, happen due to the germline mutation of (ENG, ACVRL1, SMAD4) and (RASA1, EPHB4), respectively. (14, 15) Here, Chase R. Solomon and Anne M. Comi summarized the latest progress of Sturge-Weber syndrome, most commonly associated with a R183Q somatic mosaic mutation in the gene GNAQ, from a translational perspective (https://www.frontiersin.org/articles/10.3389/fneur.2024.1493873). (16)Given the complex category and comprehensive system of vascular anomalies, scientists and clinicians are still facing tremendous challenges in basic, clinical, and translational research. Nevertheless, the knowledge base related to vascular anomalies continues to accrue and further studies are needed to allow for the treatment optimization of these challenging conditions.

Over the past 30years, the treatment of deep and eloquent arteriovenous malformations (AVMs) has moved away from microneurosurgical resection and towards medical management and the so-called minimally invasive techniques, such as endovascular embolization and radiosurgery. The Spetzler-Martin grading system (and subsequent modifications) has done much to aid in risk stratification for surgical intervention; however, the system does not predict the risk of hemorrhage nor risk from other interventions. In more recent years, the ARUBA trial has suggested that unruptured AVMs should be medically managed. In our experience, although these eloquent regions of the brain should be discussed with patients in assessing the risks and benefits of intervention, we believe each AVM should be assessed based on the characteristics of the patient and the angio-architecture of the AVM, in particular venous hypertension, which may guide us to treat even high-grade AVMs when we believe we can (and need to) to benefit the patient. Advances in imaging and intraoperative adjuncts have helped us in decision making, preoperative planning, and ensuring good outcomes for our patients. Here, we present several cases to illustrate our primary points that treating low-grade AVMs can be more difficult than treating high-grade ones, mismanagement of deep and eloquent AVMs at the behest of dogma can harm patients, and the treatment of any AVM should be tailored to the individual patient and that patient's lesion.

Peripheral vascular anomalies represent a rare disease with an underlying congenital mesenchymal and angiogenetic disorder. Vascular anomalies are subdivided into vascular tumors and vascular malformations. Both entities include characteristic features and flow dynamics. Symptoms can occur in infancy and adulthood. Vascular anomalies may be accompanied by characteristic clinical findings which facilitate disease classification. The role of periinterventional imaging is to confirm the clinically suspected diagnosis, taking into account the extent and location of the vascular anomaly for the purpose of treatment planning. In accordance with the International Society for the Study of Vascular Anomalies (ISSVA), vascular anomalies are mainly categorized as slow-flow and fast-flow lesions. Based on the diagnosis and flow dynamics of the vascular anomaly, the recommended periinterventional imaging is described, ranging from ultrasonography and plain radiography to dedicated ultrafast CT and MRI protocols, percutaneous phlebography and transcatheter angiography. Each vascular anomaly requires dedicated imaging. Differentiation between slow-flow and fast-flow vascular anomalies facilitates selection of the appropriate imaging modality or a combination of diagnostic tools. Slow-flow congenital vascular anomalies mainly include venous and lymphatic or combined malformations. Ultrasound and MRI and especially MR-venography are essential for periinterventional imaging. Arteriovenous malformations are fast-flow vascular anomalies. They should be imaged with dedicated MR protocols, especially when extensive. CT with 4D perfusion imaging as well as time-resolved 3D MR-A allow multiplanar perfusion-based assessment of the multiple arterial inflow and venous drainage vessels of arterio-venous malformations. These imaging tools should be subject to intervention planning, as they can reduce procedure time significantly. Fast-flow vascular tumors like hemangiomas should be worked up with ultrasound, including color-coded duplex sonography, MRI and transcatheter angiography in case of a therapeutic approach. In combined malformation syndromes, radiological imaging has to be adapted according to the dominant underlying vessels and their flow dynamics. Guide to evaluation of flow dynamics in peripheral vascular anomalies, involving vascular malformations and vascular tumors with the intention to facilitate selection of periinterventional imaging modalities and diagnostic and therapeutic approach to vascular anomalies. · Peripheral vascular anomalies include vascular malformations and vascular tumors. Both entities represent a rare disease with an underlying congenital mesenchymal or angiogenetic disorder. · The role of periinterventional imaging is confirmation ofthe diagnosis by assessing the flow dynamics of the vascular anomaly. · Slow-flow congenital vascular anomalies include venous, lymphatic and venolymphatic malformations. Arteriovenous malformations are fast-flow vascular anomalies, whereas hemangiomas are fast-flow vascular tumors that are frequently associated with fast-flow arteriovenous shunts. The periinterventional imaging modalities of choice include dedicated MR protocols and CT with 4D perfusion imaging as well as invasive transcatheter angiography.. · Sadick M, Overhoff D, Baessler B et al. Peripheral Vascular Anomalies - Essentials in Periinterventional Imaging. Fortschr Röntgenstr 2020; 192: 150 - 162.

Extracranial vascular malformations are abnormal formations of blood vessels located outside the brain (extracranial) that develop during fetal development. They are caused by errors in the formation of blood vessels in the embryo and can affect various parts of the body, such as the head, neck, face, and other regions. Some malformations may be asymptomatic and only require monitoring, while others may cause significant health issues or cosmetic concerns and may need medical intervention. There are very few studies have investigated the nationwide incidence and quantitative mortality of vascular malformations in terms of their subtypes. Thus, this study aimed to determine the nationwide incidence and mortality associated with vascular malformations. This nationwide population-based study evaluated 70,517 patients with vascular malformations from 2008 to 2021. We evaluated the incidence and mortality associated with each subtype of vascular malformation. Furthermore, Cox regression analysis was used to evaluate the association between vascular malformation and mortality. The annual incidence (per 100,000 population) of overall vascular, venous, capillary, arteriovenous, and lymphatic malformations was 9.85, 1.48, 2.31, 0.24, and 5.82 cases, respectively. Patients with vascular malformations, except those with venous malformations, had higher mortality than the matched controls. Moreover, among the vascular malformation subgroups, the adjusted hazard ratio of mortality was the highest for arteriovenous malformations. This study revealed that the overall annual incidence of vascular malformations was 9.85 cases per 100,000 population in Korea from 2008 to 2021. The mortality of the matched general population was lower than that of patients with vascular malformations, except for those with venous malformations. Additionally, the adjusted hazard ratio for mortality associated with arteriovenous malformations was the highest among the vascular malformation subgroups.

A term, large-for-gestational age boy is transferred from an outside hospital with a right anterior chest wall mass noted since birth. His mother is a healthy 33-year-old gravida 4, para 4 woman with good prenatal care and normal prenatal laboratory values who had an uncomplicated pregnancy and elective cesarean delivery. None of the patient’s siblings or family members have had similar masses.On physical examination the patient is well-appearing and moving all 4 extremities spontaneously without obvious limitations. Vital signs on admission to the hospital are normal. There is a nontender, boggy, fluctuant, flesh-colored, grapelike mass from his right nipple to the midaxillary line that extends to the right upper arm, with dimpling of the skin throughout the right upper extremity (Fig 1). No bruit is heard over the lesion. There is no palpable bony abnormality. Radial pulses are 2+. Capillary refill is less than 2 seconds. His lungs are clear to auscultation. The cardiovascular examination reveals a normal heart rate, rhythm, S1, and S2 and no murmurs. The abdomen is soft, nontender, and nondistended, with no palpable masses or hepatosplenomegaly.Chest radiography is normal. Complete blood cell count with differential count is normal. Ultrasonography of the right superolateral chest shows a multiloculated fluid collection with undulating borders measuring 6 × 1.7 cm. Magnetic resonance imaging (MRI) with contrast of the chest and right upper extremity reveals a multiloculated macrocystic mass in the superficial right chest wall, additional cysts in the right arm, and a partially cystic right mediastinal mass (Figs 2 and 3). MRI also shows multiple cysts in both kidneys (Fig 4). Review of the findings from MRI and genetic testing reveal the diagnoses.The differential diagnosis includes lymphatic malformation, venous malformation, vascular tumor, arteriovenous malformation, arteriovenous fistula, and capillary malformation. The patient was diagnosed as having lymphatic malformation. In addition, rapid genome sequencing revealed de novo pathogenic variant of PKD1 mutation, supporting an incidental second diagnosis of autosomal dominant polycystic kidney disease (ADPKD).Lymphatic malformations are a type of vascular anomaly. The International Society for the Study of Vascular Anomalies stratifies vascular anomalies into vascular tumors (benign, locally aggressive or borderline, and malignant) and vascular malformations (simple, combined, anomalies of major named vessels, and vascular malformations associated with other anomalies). (1)(2) Lymphatic malformations are low-flow, nonmalignant vascular malformations of the lymphatic system with dilated lymphatic channels or cysts thought to occur during lymphatic development.Lymphatic malformations can affect 1 location or can be loculated and/or multifocal (eg, lymphangiomatosis). (3) Lymphatic malformation is an umbrella term that includes all subtypes of lymphatic malformations, including cystic lymphatic malformations (macrocystic, microcystic, or mixed), generalized lymphatic anomalies such as kaposiform lymphangiomatosis, channel-type lymphatic malformation, acquired progressive lymphatic anomaly (acquired progressive lymphangioma), and primary lymphedema. Lymphatic malformations can affect any area of the body but most commonly occur in the head and neck regions, followed by the extremities. (4) They are classified as macrocystic, microcystic, or mixed. Most are noted at birth or within the first 2 years after birth.Superficial lymphatic malformations or deep vascular lesions may have no skin discoloration. In contrast, superficial arterial, capillary, or venous vascular anomalies can appear red, pink, violaceous, or blue, depending on the mix of oxygenated (arterial) or deoxygenated (venous) blood. Superficial lymphatic malformations can have clear vesicles or pitting of the skin or appear bruised if bleeding occurs within the malformation. Venous malformations are often bluish, soft, and compressible papules. Capillary malformations are often pink, red, or purple flat macules or patches. High-flow malformations, such as arteriovenous malformations and arteriovenous fistulas, can have a palpable bruit or thrill. Vascular anomalies can cause overgrowth and swelling in the affected area, which could cause pain.Lymphatic malformations can be associated with other anomalies. Gorham-Stout syndrome, also known as vanishing bone disease, is a rare condition characterized by proliferation of lymphatic vessels adjacent to single or multiple bones, leading to osteolysis and resorption of bone, oftentimes the ribs, spine, pelvis, skull, clavicle, or jaw. (5) Several PIK3CA-related overgrowth spectrum conditions also have lymphatic malformations, such as Klippel-Trenaunay syndrome, a rare congenital syndrome characterized by cutaneous capillary malformations (port-wine stain), vascular or lymphatic malformations, and limb overgrowth. (1)(6) Many patients with lymphatic malformations have an activating somatic PIK3CA gene mutation. (7) This was not the case for our patient.Diagnosis of vascular malformation or neoplasm is often made clinically and confirmed by imaging. For initial imaging, the 2019 American College of Radiology Appropriateness Criteria for Clinically Suspected Vascular Malformation of the Extremities deems magnetic resonance angiography with and without contrast, MRI with and without contrast, computed tomographic (CT) angiography with contrast, and duplex Doppler ultrasonography as appropriate for suspected vascular malformation of the extremity presenting with physical deformity. (8) However, because our patient also had a suspected abnormality in the chest wall, MRI or magnetic resonance angiography with and without contrast would be the best initial study to better evaluate deeper lesions than ultrasonography and better evaluate soft tissue contrast than CT angiography.The presence of renal cysts initially raised concern for underlying lymphangiomatosis. Lymphangiomatosis is the term used to describe lymphatic malformations in multiple organs. (3) It can affect any region of the body, although it is most common in the neck, axilla, retroperitoneum, and mediastinum. Renal lymphangiomatosis in pediatric patients is rare but should be included in the differential diagnosis for conditions such as ADPKD, nephroblastomatosis, lymphoma, and hydronephrosis with perinephric urinoma. (9) Several case reports describe initial misdiagnosis of renal lymphangiomatosis as ADPKD. Imaging and genetic testing can help differentiate between renal lymphangiomatosis and ADPKD. In renal lymphangiomatosis, renal cysts are central in the renal sinus, whereas in ADPKD, renal cysts are peripheral and parenchymal, as was seen with this patient. (9) In addition, the patient’s rapid genome sequencing reveals de novo pathogenic variant of PKD1 mutation, which supports a diagnosis of ADPKD being a separate etiology for renal cysts from that underlying the lymphatic malformations in the chest and right upper extremity. Differentiation between renal lymphangiomatosis and ADPKD can affect the treatment regimen and prognosis. A case report describing an infant with biopsy-proven bilateral renal lymphangiomatosis with 1-year follow-up suggests a self-limiting course in some patients, although it can expand before regression. (10) Successful treatment for renal lymphangiomatosis with sclerotherapy has been described. (3)(9)A case report describing an adult with comorbid lymphangiomatosis and ADPKD hypothesized a link between ADPKD and lymphangiomas as cystic pathologies sharing common genetic and congenital processes; however, no genetic mechanism has been identified. (11)ADPKD is the most common hereditary kidney disease, with a prevalence of 1:1,000 to 1:2,500. Patients with ADPKD develop cysts in the kidney parenchyma, which often leads to end-stage kidney disease by age 50 to 60 years. Our patient’s incidental diagnosis of ADPKD is atypical for several reasons. There was no family history, he developed cysts in the neonatal period, and his presenting complaint was lymphatic malformations. Our patient had a de novo PKD1 mutation, the most common mutation seen in ADPKD. Patients with PKD1 mutations have a less favorable kidney prognosis than patients with PKD2 mutations, who have end-stage kidney disease in their 70s and 80s. The Predicting Renal Outcomes in Polycystic Kidney Disease score combines predictive genetic factors with clinical information to predict risk of progression to end-stage kidney disease for patients with ADPKD in patients older than 35 years. (12) ADPKD is typically diagnosed using renal ultrasonography in patients with an affected first-degree relative. Genetic analysis can be useful in very young patients without a family history of ADPKD, as in our patient, who was found to have a de novo PKD1 mutation.Symptoms from lymphatic malformations vary depending on location of involvement and extent of invasion. Management varies depending on location, size and symptoms (including compression or obstruction of adjacent structures), infection, and interference with quality of life, including cosmetic concerns. Generally, microcystic lymphatic malformations are more challenging to treat than are macrocystic lymphatic malformations because they are less accessible for aspiration or sclerosing. (1)Observation for potential spontaneous regression can be appropriate for small lymphatic malformations without compromise of other systems. (13) Compression dressing is a conservative, first-line option for symptomatic treatment of lymphatic malformations limited to the extremities to prevent pain or growth of the malformation. (4) Treatment options for large or symptomatic lymphatic malformations include sclerotherapy, endovenous laser ablation, radiofrequency ablation, and surgical resection. Drug therapy with sirolimus, sildenafil, or propranolol has been described in case reports. Antibiotics should be used to treat infected lymphatic malformations.Clinical trials in adults with ADPKD show that angiotensin-converting enzyme inhibitors and possibly vasopressin antagonists decrease renal cyst growth. (14) A randomized controlled trial with tolvaptan, a selective vasopressin antagonist, for pediatric ADPKD is underway for children aged 12 to 17 years; results are not yet available. (15) Schaefer et al suggest angiotensin-converting enzyme inhibitors and angiotensin receptor blockers for management of hypertension and proteinuria in the setting of pediatric ADPKD. (15) In addition, there is limited evidence that statin therapy slows the progression of structural kidney disease in children and young adults with ADPKD. (16)The patient was evaluated by a multidisciplinary team including surgery, hematology/oncology, nephrology, genetics, and interventional radiology; he was referred for sclerotherapy but was lost to follow-up.Five months later he presented with cough and was diagnosed as having a parainfluenza infection. Chest radiography revealed airway compromise; CT showed that the intrathoracic extent had dramatically increased, resulting in mediastinal shift and tracheal narrowing (Fig 5). Dark, sanguineous fluid was drained from the lesion, and sclerotherapy was performed using bleomycin. The postsclerotherapy radiograph showed mass reduction and improved lung expansion.Persistent hypertension was treated with enalapril. Repeated renal ultrasonography, compared with postnatal imaging, showed an enlarging right cyst and a new left cyst. Intrathoracic sclerotherapy was repeated 40 days later. Further treatment will be required.

President's Opening Remarks.- Coordination of Neurosurgical Training in the Europe of the 1990s.- Winning Poster Presentations.- Perioperative Monitoring of Subarachnoid Hemorrhage: Transcranial Doppler Sonography and Somatosensory Evoked Potentials.- Mechanisms of K+-induced Glial Swelling.- Effects of Anesthetic Agents on Brain Edema and Cerebral Blood Flow from a Focal Cold Lesion in Rabbit Brain.- Single-Stage Neuro-rhinosurgical Operation and Management of Malignant Tumors of the Anterior Cranial Skull Base.- Vascular Malformations of the Brain.- Diagnostic and Interventional Neuroradiology of Brain Arteriovenous Malformations: Implications on Angioarchitecture for Embolization.- Embolization Techniques in the Treatment of Cerebral Arteriovenous Malformations.- Results of Combined Endovascular and Surgical Treatment of Intracranial Arteriovenous Malformations.- Indications, Technique, and Results of Microsurgical Treatment of Intracranial Arteriovenous Malformations.- Surgical Problems in Partially Embolized Angiomas.- Arteriovenous Malformations of the Brain: What is the Best Way to Treat Them?.- Arteriovenous Malformations of the Medial Surface of the Parieto-occipital Region and the Basal Ganglia.- Considerations on the Coexistence of Intracranial Arteriovenous Malformations and Aneurysms.- Follow-up After Treatment for Intracranial Arteriovenous Malformations.- Posterior Fossa Arteriovenous Malformations: Angioarchitecture in Relation to Hemorrhagic Episodes.- Clinical and Radiological Prognostic Factors in Cerebral Arteriovenous Malformations.- Venous Angiomas: Experience with Surgical and Nonsurgical Management.- Intracranial Venous Angiomas.- Congestive Cardiac Manifestations from Cerebrocranial Arteriovenous Shunts.- Neuropsychological Abnormalities in Patients with Cerebral Arteriovenous Malformations: A Pilot Study.- Cerebral Cavernous Hemangiomas: Treatment and Surgical Decisions.- Microsurgery of Cavernous Angiomas of the Brain with Special Reference to Cerebral Midline Localizations.- 667 Histologically Verified Cavernous Hemangiomas of the CNS: Review of Localization, Symptoms, and Signs, Diagnosis, and Results of Operative Treatment.- Asymptomatic Cryptic Vascular Malformations.- Supratentorial Tumors in Childhood.- Pediatric Brain Tumors.- Multidisciplinary Approach to the Treatment of Supratentorial Tumors in Children.- Treatment and Course of Malignant Supratentorial Brain Tumors in Childhood.- Interstitial Irradiation of Supratentorial Cerebral Gliomas in Childhood with Permanently Implanted Iodine 125: Preliminary Results.- Radiological Results of Intracavitary Brachytherapy of Cystic Craniopharyngioma in Childhood and Adolescence.- Long-Term Results of Combined Surgery and Radiotherapy of Pilocytic Astrocytomas in the Middle Cranial Fossa.- Discussion: PNET - A Melting-Pot of Unspecified Tumors?.- Prognosis of Supratentorial Gliomas in Children.- Proliferative Activity of Pilocytic Astrocytomas: Examination Using Monoclonal Antibody Ki-67.- Immunohistochemical Investigations with a Monoclonal Anti-Epidermal Growth Factor Receptor Antibody in Supratentorial Tumors in Children.- Neurosurgical Intensive Care.- Neurosurgical Intensive Care - An Interdisciplinary Field.- Neurosurgical Intensive Care: General Considerations.- Prognostic Value of Motor Evoked Potentials in Traumatic and Nontraumatic Coma.- The Temporal Structure of Information Processing in Patients Following Diffuse Head Injuries: Electrophysiological Studies.- TCD, SEPs and ICP: Comparative Analysis in Severe Head Injury.- Parenteral Nutrition in Patients with Spontaneous Intracranial Hemorrhages.- Susceptibility to Infection During Continuous Thiopentone Therapy.- Infection Rate and Bacterial Spectrum in 413 Patients of a Neurosurgical Intensive Care Unit: Results of a 2-year Prospective Study.- Risk During the First Hours After Severe Head Injury.- Disturbances of Water-Electrolyte Regulation After Surgery of the Hypothalamus and Pituitary Region.- CBF Dynamics During Hyperventilation Therapy for Intracranial Hypertension.- THAM in Traumatic Brain Swelling: A Comparative Experimental and Clinical Study.- Effects of the Antihypertensive Drug Ketanserin on Intracranial Pressure in Patients with Head Trauma.- A Comparison Between Mannitol and Glycerol Therapy for Intracranial Hypertension.- Decompressive Craniectomy After Severe Head Injury: Useful Therapy in Pathophysiologically Guided Indication.- Safety of Fraxiparine Administration in Neurosurgical Patients: Preliminary Report.

Arteriovenous malformations (AVMs) are vascular pathologies in which tissue trophism and blood outflow are disrupted due to the congenital or acquired absence of capillaries and the formation of a single conglomerate in which the arteries pass directly into the veins. Aim: to share our experience in the diagnosis and treatment of AVM of the colon in children. Material and methods. Clinical case No. 1. A 4-year-old girl was admitted to the N.F. Filatov State Clinical Hospital with a clinical picture of gastrointestinal bleeding (GCC). For the first time, an episode of stool with streaks of blood was observed at 2 years and 4 months. The examination revealed ulcerative colitis in the rectum, multiple erosions covered with fibrin were found. Long-term conservative therapy with no effect. Upon admission to the clinic, the child’s condition is moderate, the stool is light brown, and there is dark blood on top of it in the amount of 3-4 drops. According to ultrasound data, a thickening of the walls of the rectum with a slight increase in blood flow in them is determined above the anus. During the radioisotope study, an increase in the accumulation of RFP in the lower abdominal cavity was revealed. CT scans of the abdominal cavity and pelvis with contrast indicate increased vascularization of the walls of the middle and lower third of the rectum. Ultrasound of the sigmoid and rectum was performed: at a distance of 40 mm from the anus, an area in the rectal wall was visualized in which blood flow was increased during CDK, and venous vessels with arterial pulsation in them were also detected there. Endovascular angiography was performed, and intestinal AVM was detected (in the venous phase, dilated pathological veins can be traced projectively to the ampoule of the rectum). Taking into account the intensity of bleeding (5-6 times a day), it was decided to remove the pathological part of the colon. Laparoscopic resection of the sigmoid and rectum according to Swanson was performed in two stages. During the first stage, during the revision and mobilization of the colon at the level of the superior sigmoid artery, a large number of dilated vessels were found in the mesentery, and pathological vessels were also detected along the posterior wall of the rectum. On 4-5 postoperative days, the bleeding resumed, which indicated the formation of collateral blood flow. On the 14th day after stabilization, the second stage of Swanson surgery was performed - a direct coloctal anastomosis was performed. The bleeding continued. A decision was made to disconnect the rectum and apply an ileostomy. However, in the postoperative period, abundant mucous discharge with a hemorrhagic component remained from the rectum. Repeated angiography was performed - the vessel feeding the AVM was identified and embolized - the volume of bleeding decreased, but it was not possible to completely stop it. A decision was made to perform a colectomy and form an ileoanal anastomosis. Intraoperatively, marked lymphorrhea, tortuosity, and vasodilation of the mesentery were noted during intestinal discharge. In the postoperative period, blood in the stool was observed in the form of rare veins, which eventually disappeared. Clinical case No. 2. A 10-year-old girl was admitted to the clinic complaining of blood in her stool. It is known from the medical history that for 2 years the child has been worried about periodic pain in the left side of the abdomen. A year ago, the first episode of blood in the stool. During the examination, the diagnosis of UAC was established - conservative therapy was prescribed, against which remission was noted for about 3 months. Further, the resumption of GCC was noted, despite the ongoing treatment. A radioisotope study was performed, and an increased accumulation of RFP was detected in the left abdominal cavity. Upon admission, the condition is of moderate severity, the child is malnourished. The abdomen is soft on palpation, moderately painful in the left abdomen. The stool is mushy, with an admixture of blood and mucus, a tendency to diarrhea. According to the results of angiography, AVM of the colon was detected: in the descending part of the colon and in the rectum, the pathological tortuosity of small arterioles with increased capillary blood flow was contrasted. To eliminate life-threatening bleeding, a left-sided hemicolectomy with the formation of a colostomy was performed. Intraoperatively, telangiectasia was detected along the anterior surface of the rectum, the vessels in the colon and the left half of the intestine were dilated to 4-5 mm. In the postoperative period, the child had minor bleeding from the distal rectum. Clinical remission was achieved within 1 year. Discussion. It is believed that AVM occurs in 1 in 10,000 people, while in the literature, the localization of AVM in the colon or small intestine is described in no more than a hundred observations, of which 80% of cases are localized in the left half of the colon or rectum. The most common symptoms of this pathology are GCC, accompanied by the development of iron deficiency anemia. It is worth noting that AVM of the large intestine is often hidden under the guise of inflammatory bowel diseases. Children have been receiving inappropriate therapy for years, which can be misdiagnosed as drug resistance. Conclusion. The diagnosis of AVM is established using imaging research methods. In case of accidental detection of AVM, wait-and-see tactics are used due to the high traumatic nature of surgical treatment. If symptoms are present, endoscopic laser or thermocoagulation, resection of the affected area, or endovascular treatment is possible.

Introduction: The most common cause of intracranial bleeding in younger patients and children are vascular anomalies. Digital subtractions angiography presents a gold standard in diagnostics of aneurisms and vascular malformations. Our aim is to present our experience in using computed tomography angiography in diagnosing arteriovenous malformations.
 Methods: We included 150 patients with acute non-traumatic intracranial hemorrhage diagnosed by non-contrast CT examination, after which they were subjected to CT angiography of the cerebral vessels, and then underwent maximum intense projection and volume rendering reconstruction.
 Results: Out of 150 patients with non-traumatic intracranial hemorrhage, in 121 (81%) a diagnosis of aneurysm was rendered, while in 8 (5%) arteriovenous malformation was found. In 29 (14%) patients cause of bleeding was not identified. Patients with arteriovenous malformations, were age 17-77 years, with mean age 42.75 years. Five (62.5%) of them were female patients and three (37.5%) were male.
 Conclusion: Spontaneous non-traumatic intracranial hemorrhage is a significant cause of morbidity and mortality. Computed tomography angiography is sufficiently specific and sensitive in diagnosis of arteriovenous malformations in our experience.

Various techniques and materials have been used for the endovascular treatment of craniofacial high-flow arteriovenous vascular malformations, because their rarity precludes standardization of their treatment. The aim of this retrospective review is to assess Onyx as the primary embolic agent in the treatment of these vascular malformations. Six patients with arteriovenous fistulas and 3 with arteriovenous malformations (AVMs) of the head and neck region were treated with intra-arterial (IA)/direct percutaneous injections of Onyx. Adjunctive maneuvers used during embolization included external compression of the arterial feeders or venous outflow (6 patients), balloon assist (4 patients), and direct embolization of the draining vein remote to the fistula site (1 patient). n-butyl-2-cyanoacrylate (n-BCA) was used in addition to Onyx for rapid induction of thrombosis in a large venous pouch (1 patient) and for cost containment purposes (1 patient). Four patients were treated surgically after the embolization. There were no neurologic complications secondary to the embolization procedure. The arteriovenous shunt was eliminated in all of the fistulous lesions and 2 of the 3 AVMs. The embolization was incomplete in 1 patient with a large AVM who declined further endovascular or surgical procedures. Untoward events included 2 instances of catheter entrapment (of 9 IA injections), blackish skin discoloration necessitating surgical revision in 1 patient, and difficulty of balloon deflation/wire withdrawal during a balloon-assisted embolization. Onyx appears to be a safe and effective liquid embolic agent for use in the treatment of craniofacial high-flow vascular malformations with distinct advantages and disadvantages compared with n-BCA.

Vascular anomalies are a diagnostic and therapeutic challenge. They require dedicated interdisciplinary management. Optimal patient care relies on integral medical evaluation and a classification system established by experts in the field, to provide a better understanding of these complex vascular entities. A dedicated classification system according to the International Society for the Study of Vascular Anomalies (ISSVA) and the German Interdisciplinary Society of Vascular Anomalies (DiGGefA) is presented. The vast spectrum of diagnostic modalities, ranging from ultrasound with color Doppler, conventional X-ray, CT with 4 D imaging and MRI as well as catheter angiography for appropriate assessment is discussed. Congenital vascular anomalies are comprised of vascular tumors, based on endothelial cell proliferation and vascular malformations with underlying mesenchymal and angiogenetic disorder. Vascular tumors tend to regress with patient's age, vascular malformations increase in size and aresubdivided into capillary, venous, lymphatic, arterio-venous and combined malformations, depending on their dominant vasculature. According to their appearance, venous malformations are the most common representative of vascular anomalies (70 %), followed by lymphatic malformations (12 %), arterio-venous malformations (8 %), combined malformation syndromes (6 %) and capillary malformations (4 %). The aim is to provide an overview of the current classification system and diagnostic characterization of vascular anomalies in order to facilitate interdisciplinary management of vascular anomalies. · Vascular anomalies are comprised of vascular tumors and vascular malformations, both considered to be rare diseases.. · Appropriate treatment depends on correct classification and diagnosis of vascular anomalies, which is based on established national and international classification systems, recommendations and guidelines.. · In the classification, diagnosis and treatment of congenital vascular anomalies, radiology plays an integral part in patient management.. · Sadick M, Müller-Wille R, Wildgruber M et al. Vascular Anomalies (Part I): Classification and Diagnostics of Vascular Anomalies. Fortschr Röntgenstr 2018; 190: 825 - 835.