Undiagnosed scrotal swelling in a 36-year-old man: A congenital arteriovenous malformation.

We have reported the case of a 36-year-old man with severe scrotal swelling that had remained undiagnosed after multiple diagnostic tests. The patient had presented with scrotal swelling, multiple weeping ulcers on the dorsal aspect of the scrotum, and worsening pain affecting his day-to-day functioning. Duplex ultrasound showed low- to no-flow hypervascularity and dependent edema suspicious for a vascular malformation. Treatment included sequential Gelfoam (Pfizer, New York, NY) embolization using ultrasound-guided direct cannulation and traditional angiography. The scrotal circumference decreased by 65%, with moderate relief of his pain. The details from the present case have highlighted the significance of vascular malformations, various diagnostic and therapeutic techniques used, and value of endovascular embolization.

Regimens and Response Assessment in Minimally Invasive Image-Guided Therapies for Vascular Malformations: Insights from a Large Cohort Study at a Tertiary-Care Hospital.

This retrospective study was aimed at characterizing vascular malformations (VMFs) presenting for minimally invasive image-guided therapies (MIT) at a tertiary-care center and evaluating treatment regimens and image-based outcomes using MRI. We analyzed demographic, disease-related, and radiologic features of VMFs presenting to interventional radiology between May 2008 and August 2020 using compendium vascular anomaly (Compva) criteria. MIT and specific agents were evaluated, and treatment effects were assessed through volumetry and mean signal intensity (MSI) on multiparametric longitudinal MRI. The statistics included the paired t-test, ANOVA, and Fisher's exact test. The cohort included 217 patients (mean age 30 ± 18.4 years; 134 female). Venous malformations were most common (47%). VMFs were frequently located in the head-neck region (23.5%), legs (23.04%), and arms (13.8%). Among 112 treatments, sclerotherapy was performed most frequently (63.9%), followed by embolization (19.3%). MRI showed a significant reduction in T2 MSI for venous (1107.95 vs. 465.26; p = 0.028) and decreased contrast media uptake for lymphatic malformations (557.33 vs. 285.33; p = 0.029) after sclerotherapy, while the lesion volumes did not change significantly (p = 0.8). These findings propose MRI-derived MSI as a potential non-invasive biomarker for assessing the response of VMF to MIT. By leveraging MRI, this study addresses challenges in managing rare diseases like VMFs, while advocating for standardized approaches and prospective studies to better link imaging findings with clinical outcomes.

Magnetic Resonance Imaging (MRI) Evaluation and Classification of Vascular Malformations.

Introduction Vascular malformations of the soft tissues are a diverse collection of lesions frequently encountered in clinical practice. Vascular malformations are rare and complex abnormalities that affect both children and young adults. Low-flow malformations are more common in children and often become symptomatic in later years. These malformations are common causes of soft tissue masses in children and can affect any part of the body at any age. Significant advancements in the management of these conditions have been made due to the implementation of a comprehensive binary categorization system, which classifies vascular abnormalities into tumors and malformations based on their clinicopathological characteristics. Imaging, particularly magnetic resonance imaging (MRI), plays a crucial role in the accurate identification, localization, and classification of these lesions, aiding in the development of appropriate treatment plans. Materials and methods This prospective study was conducted at Dr. D. Y. Patil Medical College, Hospital and Research Centre, Pimpri, Pune, from August 2022 to June 2024. Fifty patients of all age groups with clinically suspected soft tissue vascular malformations were included. MRI was performed using a MAGNETOM Vida (3T) Scanner (Siemens Healthcare Private Limited, Mumbai, India), and ultrasound was used as an adjunct. Institutional Ethics Committee clearance and informed consent were obtained. The study employed various MRI sequences, including T1-weighted imaging (T1WI) fast spin echo (FSE), T2-weighted imaging (T2WI) FSE, short tau inversion recovery (STIR), T2-weighted gradient recalled echo (GRE), pre-contrast fat-saturated T1WI, 3D post-contrast T1WI, diffusion-weighted imaging (DWI), and ANGIO TWIST (time-resolved angiography with interleaved stochastic trajectories) ISO. Results The study included 50 patients, with a male predominance of 28 (56%). The mean age was 22.13 years, and the average duration of vascular malformations was 32.94 months. The swelling was present in 43 (86%) of patients, and 35 (70%) had superficial lesions. MRI findings revealed hypointensity on T1 imaging in 40 (80%) patients and hyperintensity on T2 imaging in 49 (98%) cases. STIR sequences showed hyperintensity in all patients. The most common type of vascular malformation was slow-flow 46 (92%), with venous malformations being the most prevalent 39 (78%). Conclusion MRI is a valuable imaging modality for the evaluation and classification of vascular malformations, providing detailed information on lesion extent and involvement of surrounding tissues. The findings support the use of MRI as a primary tool in the assessment of vascular malformations, with ultrasound serving as a useful adjunct in certain cases. Further studies with larger sample sizes are recommended to validate these findings and refine imaging protocols.

Efficacy and safety of hyaluronic-polidocanol foam in sclerotherapy for head and neck venous malformations.

Background: Foam sclerotherapy is currently the first-line treatment for venous malformations (VMs). Hyaluronic acid-polidocanol (HA-POL) foam has been used in the treatment of head and neck VMs recently; however, its clinical efficacy and safety have yet to be further evaluated, and the impact of age and other related factors on its safety is still unclear. Objective: To assess the efficacy and safety of HA-POL foam in the treatment of head and neck VMs. Methods and materials: We performed a single-center retrospective review of all patients with VMs involving the head and neck region undergoing HA-POL foam sclerotherapy from February 2015 to February 2022 in the Oral and Maxillofacial Surgery Department of Qilu Hospital Shandong University. Patients' medical records were collected and all patients enrolled were followed up for 1-6 months (group 1), part of them were followed up for 3-9 years (group 2). Results: A total of 223 patients with head and neck VMs were enrolled in the study, with 36 patients who were followed for 3-9 years. Total response rate in group 1 was 96.41% (n = 215), of which 30.94% (n = 69) of the patients met the criteria of "resolution," and 65.47% (n = 146) of the patients had "significant improvement." In group 2, the total response rate was 72.22% (n = 26), of which the rates of the patients met the criteria of "resolution" and patients had "significant improvement" were all 36.11% (n = 13)0.144 (64.57%) patients experienced complications like localized swelling, pain and fever, and no serious complications occurred. The risk of developing complications after treatment was independent of age, and was weakly associated with the dose of HA-POL foam. Conclusion: The HA-POL foam sclerotherapy is safe and effective in the treatment of head and neck VMs.

Surgical treatment of small-sized S3 arterio-venous malformations with neo-adjuvant and adjuvant bleomycin.

Arteriovenous Malformations are complex and challenging entities, and their treatment is often tailored on the patient. Interstitial sclerosing treatment with bleomycin is promising especially in cases where the aesthetical and/or functional burden of surgical intervention would be impactful as in the S3 AVM according to the SECg classification. We treated 15 patients presenting small (<10cm3) S3 arterio-venous malformations with 3 + 3 sessions of 15.000 IU of interstitial bleomycin. 9 patients presented moderate to good response to the first 3 sessions and thus surgical re-shaping was performed between the two cycles. US examination was done pre-treatment, before each session and every 3 months after the end of the protocol to assess the arterio-venous malformations. Fifteen of the seventeen patients concluded the protocol. 9 patients underwent surgical re-shaping while 6 skipped it because of their excellent response to the first 3 bleomycin injections. Major improvement in terms of appearance and symptoms (pulsations, ulcerations, bleeding or pain) were always achieved. There was a 20% of minor complications. The presented data are encouraging and seem to suggest that this may be a promising protocol to extend the use of bleomycin in arterio-venous malformations and reduce the impact of surgery.

Bleomycin induces endothelial cell pyroptosis and regulates fibrosis by activating the NLRP3/caspase-1/GSDMD pathway: a possible mechanism contributing to the sclerotherapy of venous malformations.

Venous malformations (VMs) are slow-flow vascular anomalies that pose significant health challenges. Bleomycin (BLM) is frequently used in Sclerotherapy for VMs, but its mechanism, particularly through pyroptosis, remains poorly understood. This study explores the role of BLM-induced endothelial cell pyroptosis in VMs sclerotherapy and its regulatory effects on fibrosis via the NLRP3/caspase-1/GSDMD pathway. Using a combination of TUNEL staining, Western blotting, and immunohistochemistry, we investigated the effects of BLM on VMs and endothelial cells in vitro. Pyroptosis and fibrosis were quantified, and the involvement of the NLRP3/caspase-1/GSDMD pathway was assessed. BLM treatment significantly increased pyroptosis and fibrosis in VMs tissues and cultured endothelial cells. Activation of the NLRP3/caspase-1/GSDMD pathway was crucial for these effects, which could be mitigated by pathway inhibition. BLM regulates fibrosis and induces pyroptosis through the NLRP3/caspase-1/GSDMD pathway in VMs. Understanding this mechanism could enhance the effectiveness and safety of Sclerotherapy in clinical settings.

Ethanol foam: a novel type of foam sclerosant for treating venous malformations.

Introduction: Sclerotherapy is a commonly utilized treatment approach for venous malformations. Absolute ethanol is renowned for its remarkable efficacy as a potent sclerosants, but it is potentially associated with severe complications. Foam sclerotherapy is considered superior to liquid sclerotherapy owing to its heightened efficacy and diminished incidence of complications. Thus, our objective was to devise an ethanol foam sclerosant that delivers exceptional efficacy while mitigating complications. Methods: In the first set of experiments, we identified the suitable range of ethanol concentrations for sclerotherapy through human umbilical vein endothelial cell proliferation assays and blood clotting experiments. Next, the surfactants polysorbate 80, egg yolk lecithin, and hyaluronic acid were added to create stable ethanol foam, with their ratios meticulously optimized. Results: The optimal concentration range of ethanol was determined to be 30-60%. Eventually, a 48% ethanol foam was successfully produced with excellent stability. Other than ethanol, the formulation included 5 × 10-3 g/mL polysorbate 80, 10-2 g/mL egg yolk lecithin, and 0.04 mL/mL hyaluronic acid. Discussion: The novel ethanol foam produced here could be a promising candidate for the treatment of venous malformations.

A Rare Case of Vascular Malformation in India: Cutis Marmorata Telangiectatica Congenita.

The current case report presents a male baby, second born to nonconsanguineous parents at 38 weeks of gestation by lower segment cesarean section, with engorged blood vessels and distinctive patterns of discoloration and dilation of blood vessels on the left leg. A Doppler of the femoral artery and vein showed normal triphasic flow and waveforms without any evidence of significant luminal stenosis. There was also a lower limb length discrepancy of 1.5 cm. Genetic testing using fluorometric enzyme immunoassay screening revealed a negative screening report. Otologic screening using distortion product otoacoustic emissions revealed normal functioning of outer hair cells in both ears. The case was diagnosed as cutis marmorata telangiectatica congenita (CMTC), after ruling out genetic diseases. It was not associated with any other significant health problems. The diagnosis of CMTC was based on the appearance of the skin at birth, which became more noticeable shortly after two days. In this case, no specific treatment was warranted and the condition improved with time.

A jugular venous compression adjunct for surgical excision of distensible orbital venous malformations.

PURPOSE: Orbital venous malformations (VM) pose challenges in complete resection due to indistinct borders and bleeding proclivity. Current methods for aiding surgical excision of distensible orbital venous malformations are inadequate. We investigated whether external neck compression could facilitate intraoperative distension of venous orbital lesions during surgical excision in patients diagnosed with VM. METHODS: Eighteen patients (8 males and 10 females) diagnosed with distensible venous anomalies were enrolled. Neck compression technology, was employed to distend the lesions before puncture embolization using n-butyl-2-cyanoacrylate glue under general anesthesia. The surgical process, along with preoperative to postoperative changes in ocular symptoms, were recorded. RESULTS: The average surgical duration was 95 min. A mean of 3.41 ml surgical glue was used for embolization. The compression belt maintained pressure at 35-40 mmHg. Total lesion resection was achieved in 12 patients, with 6 patients undergoing subtotal removal not requiring supplementary surgery. Symptoms were entirely alleviated in 17 patients, and signs of distensible lesions during the Valsalva maneuver were absent. One patient underwent secondary surgery for residual eyelid lesions. Minor complications included mild ocular movement restriction, residual subcutaneous induration, transiently increased orbital pressure, and lower lid ectropion in four, three, four, and one patient, respectively. Three patients experienced a mild post-operative visual acuity decrease, although none experienced vision loss. CONCLUSIONS: Direct orbital embolization aided by a jugular vein compression device is safe and demonstrates satisfactory outcomes in orbital varicose vein treatment.

Natural History and Predictors for Hemorrhage in Supratentorial Brain Arteriovenous Malformations.

Background/Objectives: Approximately half of the patients harboring supratentorial brain arterio-venous malformations (stAVMs) present with hemorrhage, and another considerable proportion suffer from epileptic seizures. An important milestone in the management of this vascular pathology is acknowledging their natural history, especially across long periods of time. The aim of this study was to assess the predictive factors for hemorrhage and for epileptic seizures as presenting symptoms in stAVMs. Methods: We retrospectively analyzed patients with stAVMs admitted to our institution between 2012 and 2022 and evaluated predictive factors for hemorrhage and the risk factors associated with epileptic seizures. Results: The cohort included 169 patients, 78 of them (46.2%) presenting with intracerebral hemorrhage (ICH). Seventy-seven (45.5%) patients suffered from epileptic seizures. The annual hemorrhagic rate was 1.28%/year. Unruptured lesions (p = 0.001, OR 3.1, 95% CI 1.6-6.2), superficial venous drainage (p = 0.007, OR 2.7, 95% CI 1.3-5.7) and large nidus size (p = 0.025, OR 4, 95% CI 1.2-13.5) were independently associated with seizures. Among unruptured lesions, superficial venous drainage (OR 2.6, p = 0.036, 95% CI 1.06-6.3) and frontal/temporal/parietal location (OR 2.7, p = 0.040, 95 CI% 1.04-6.9) significantly increased the risk of seizures as a presenting symptom in multivariate analysis. Patients younger than 18 (p = 0.003, OR 4.5, 95% CI 1.6-12.2), those with AVMs < 3 cm (p = 0.03, OR 2, 95% CI 1.07-3.9) or those with deep located AVMs (p = 0.035, OR 2.3, 95% CI 1.06-5.1) presented statistically more often with ICH in multivariate regression. Small size (HR 1.8, 95% CI 1.09-3, p = 0.022) and exclusively deep venous drainage (HR 2.2, 95% CI 1.2-4, p = 0.009) were independent predictors for ICH, in time-dependent birth-to-diagnosis analysis. After shifting the birth-to-diagnosis curve by 10 years, unique arterial feeder demonstrated a positive correlation with ICH presentation as well. Conclusions: Small AVMs, those with exclusively deep venous drainage, unique arterial feeder or deep location may pose higher hemorrhagic risks for the patient, and therapeutic strategies should be tailored accordingly. When managing unruptured brain AVMs, it is important to consider the risk of developing seizures, in addition to the lifelong risk of hemorrhage, in determining the optimal treatment approach for each patient.

Gene expression profiling of venous malformations identifies the role of SDC1 in venous endothelial cells.

Objective: To obtain insight into the molecular process implicated in venous malformations (VMs) and identify potential targets for treatment of VMs, this study profiled the gene expression pattern in VMs, investigated alterations of syndecan-1 (SDC1) expression in VMs, and tested the hypothesis that aberrant SDC1 expression triggers abnormal angiogenesis and VM development. Methods: Microarray analysis was performed to identify differentially expressed genes (DEGs) on a transcriptome-wide level in VMs and conjunctive normal. Gene Ontology molecular functional analysis and Kyoto Encyclopedia of Genes and Genomes pathway analysis were carried out to establish enhancement of biological signaling pathways involved in VMs. Among the DEGs, we focused on SDC1, which is involved in matrix remodeling, cell proliferation and invasion, and angiogenesis. SDC1 expression in VMs was verified by qRT-PCR, western blotting, and immunohistochemistry. Loss-of-function of SDC1 was achieved in human umbilical vein endothelial cells (HUVECs) by siRNA to investigate the roles of SDC1 in cell migration, invasion, and angiogenesis. Results: Compared with control tissue, the transcriptome study identified 274 upregulated DEGs and 3 downregulated DEGs. The transcript and protein levels of SDC1 were significantly decreased in VMs compared with normal tissue. Inhibition of SDC1 enhanced HUVEC migration, invasion, and angiogenesis. Conclusion: Our genome-wide microarray analysis suggests the involvement of numerous genes in VMs. Among them, SDC1 plays a substantial role in the process of angiogenesis and development of VMs. SDC1 may represent a potential target for a molecular therapy for VMs.

Comparative analysis of the efficacy and safety of different methods for injecting polidocanol in the treatment of venous malformations.

OBJECTIVE: To compare and analyze the efficacy and safety of different methods for injecting polidocanol in the treatment of venous malformations. METHODS: The medical records of patients with venous malformations in our hospital from April 2021 to April 2023 were analyzed retrospectively, and they were divided into control group (n = 38) and observation group (n = 20) according to different treatment methods. Control group was injected with polidocanol under ultrasound guidance, while observation group was injected with polidocanol under digital subtraction angiography (DSA) monitoring. Therapeutic effects of observation group and control group after 3-6 months of treatment were compared and analyzed, and complications that can be used to reflect the safety of treatment in two groups were collected and recorded. RESULTS: After treatment, the total effective rates of observation group and control group were 97.37% (37/38) and 75.00% (15/20) respectively, with significant differences (both p < .05). After 3-6 months of treatment, 13 complications occurred in observation group, while 16 occurred in control group. The number of complications in observation group was 6, with an incidence rate of 15.78%; while that in control group was 9, with an incidence rate of 45.00%, with a significant difference (p < .05). There were no significant differences among other baseline data, age and complications between two groups (all p > .05). CONCLUSION: Injection of polidocanol in patients with venous malformations under DSA monitoring was more effective and safer.

External Jugular Vein Slow-Flow Venous Malformation Presenting as a Swelling Over the Neck: A Report of a Rare Case.

Vascular malformations originating from the wall of the external jugular vein are exceedingly uncommon. We present a unique case of a venous malformation arising from the external jugular vein, successfully treated through surgical excision with no subsequent recurrence. This case highlights the importance of early diagnosis and timely intervention in managing such rare clinical entities without any resulting morbidity.

Congenital Vascular Malformations in Children: From Historical Perspective to a Multidisciplinary Approach in the Modern Era-A Comprehensive Review.

Congenital vascular malformations (CVMs) are the result of an aberrant development during embryogenesis. Although these lesions are present at birth, they are not always visible yet. Once symptomatic, patients suffer from pain, bleeding, ulcers, infections or lymphatic leakage, depending on the subtype of vessels involved. Treatment includes conservative management, surgery, sclerotherapy, embolization and pharmacological therapy. The clinical presentation varies widely and treatment can be challenging due to the rarity of the disease and potential difficulties of treatment. This review gives an overview of the historical developments in diagnosis and classification and exposes the key elements of innovations in the past decades on the identification of genetic mutations and personalized treatment. These advances in the field and a multidisciplinary approach are highly valuable in the optimization of clinical care aimed at both curing or stabilizing the CVM and pursuing physical and psychosocial wellbeing.

Human iPSC and CRISPR targeted gene knock-in strategy for studying the somatic TIE2L914F mutation in endothelial cells.

Induced pluripotent stem cell (iPSC) derived endothelial cells (iECs) have emerged as a promising tool for studying vascular biology and providing a platform for modelling various vascular diseases, including those with genetic origins. Currently, primary ECs are the main source for disease modelling in this field. However, they are difficult to edit and have a limited lifespan. To study the effects of targeted mutations on an endogenous level, we generated and characterized an iPSC derived model for venous malformations (VMs). CRISPR-Cas9 technology was used to generate a novel human iPSC line with an amino acid substitution L914F in the TIE2 receptor, known to cause VMs. This enabled us to study the differential effects of VM causative mutations in iECs in multiple in vitro models and assess their ability to form vessels in vivo. The analysis of TIE2 expression levels in TIE2L914F iECs showed a significantly lower expression of TIE2 on mRNA and protein level, which has not been observed before due to a lack of models with endogenous edited TIE2L914F and sparse patient data. Interestingly, the TIE2 pathway was still significantly upregulated and TIE2 showed high levels of phosphorylation. TIE2L914F iECs exhibited dysregulated angiogenesis markers and upregulated migration capability, while proliferation was not affected. Under shear stress TIE2L914F iECs showed reduced alignment in the flow direction and a larger cell area than TIE2WT iECs. In summary, we developed a novel TIE2L914F iPSC-derived iEC model and characterized it in multiple in vitro models. The model can be used in future work for drug screening for novel treatments for VMs.

Fluoroscopy- and Endoscopy-Guided Transoral Sclerotherapy Using Foamed Polidocanol for Oropharyngolaryngeal Venous Malformations in a Hybrid Operation Room: A Case Series.

Background: Treatment of oropharyngolaryngeal venous malformations (VMs) remains challenging. This study evaluated the effectiveness and safety of fluoroscopy- and endoscopy-guided transoral sclerotherapy for oropharyngolaryngeal VMs in a hybrid operation room (OR). Methods: Patients with oropharyngolaryngeal VMs who underwent transoral sclerotherapy in a hybrid OR were enrolled. Results: Fourteen patients (six females, eight males; median age of 26 years; range, 4-71 years) were analyzed. The symptoms observed were breathing difficulties (n = 3), snoring (n = 2), sleep apnea (n = 1), and swallowing difficulties (n = 1). Lesions were extensive in the face and neck (n = 9) and limited in the oropharyngolarynx (n = 5). A permanent tracheostomy was performed on two patients, while a temporary tracheostomy was performed on five patients. The treated regions were the soft palate (n = 8), pharynx (n = 7), base of the tongue (n = 4), and epiglottis (n = 1). The median number of sclerotherapy sessions was 2.5 (range, 1-9). The median follow-up duration was 81 months (range, 6-141). Treatment outcomes were graded as excellent (n = 2), good (n = 7), or fair (n = 5). The post-treatment complication was bleeding (n = 1), resulting in an urgent tracheostomy. Conclusions: Fluoroscopy- and endoscopy-guided transoral sclerotherapy in a hybrid OR can be effective and safe for oropharyngolaryngeal VMs.

Efficacy of foam sclerotherapy with polidocanol for the management of oral venous malformations.

The present aimed to examine the effectiveness of polidocanol-based foam sclerotherapy for oral venous malformations (OVMs). The present study performed a retrospective analysis of patients with OVMs who underwent sclerotherapy using polidocanol. Patients achieving the complete resolution of OVM were categorized as having a complete response (CR), those with a reduction in size from the initial diagnosis were categorized as having a partial response (PR), those with no change in size as stable disease (SD), and those with an increase in size as progressive disease (PD). A total of 16 patients, comprising 4 males and 12 females, underwent treatment with polidocanol foam therapy, covering 22 affected areas. The treatment administered resulted in CR in 6 cases and PR in 10 cases, with no instances of SD or PD. Apart from localized injection site pain or swelling, there were no severe side-effects reported, such as circulatory dynamic changes or skin necrosis. On the whole, these findings underscore the effectiveness of foam sclerotherapy with polidocanol as a viable treatment for venous malformations in the oral and maxillofacial regions.

Venous Malformation in the Anterior Mediastinum.

Venous malformations (VMs) located in the anterior mediastinum are rare. Thus, diagnosis using imaging is often challenging, and they are typically diagnosed only after total tumor resection. Herein, we report a case of VM located in the anterior mediastinum diagnosed using computed tomography (CT) and magnetic resonance imaging (MRI). A 56-year-old woman presented for further evaluation of an anterior mediastinal mass observed during a chest CT. On CT, the mass was observed to have scattered calcifications and early and persistent enhancement with contrast material pooling dorsally in the delayed phase. On MRI, the mass was isointense on T1-weighted imaging and hyperintense on T2-weighted imaging without flow voids. From these images, we suspected the mass to be a VM, but the possibility of an arterial malformation/fistula could not be ruled out. Initially, a contrast material was injected via the arm, but to improve differentiation, it was also injected via the leg. The 4D-CT of the leg indicated no early enhancement of the mass; however, gradual enhancement was observed. This led to a definite diagnosis of VM. As she had no symptoms, we opted for a CT follow-up, and the mass remained stable for one year post-diagnosis. This case report underscores the usefulness of injecting contrast material through the leg in distinguishing VM from AVM/Fs in the anterior mediastinum.

Efficacy of Dose-Escalated Hypofractionated Radiosurgery for Arteriovenous Malformations.

There is considerable controversy about the management of arteriovenous malformations (AVMs) that are high risk for surgical resection. Stereotactic radiosurgery (SRS) has a reported success rate of less than 50% with unacceptably high rates of radiation necrosis with larger AVM volumes. Neither volume staging nor hypo-fractionated SRS have conclusively been demonstrated to improve results. We hypothesized that the failure of previous hypo-fractionation SRS trials was due to an insufficient biologically effective dose (BED) of radiation. We initiated a pilot study of treating AVM patients with a total dose divided into three or five fractions designed to deliver the equivalent BED of 20 Gy in a single fraction (α/ß =3). We performed a retrospective analysis of 37 AVM patients who had a minimum of two years of follow-up or underwent obliteration. Patients were treated with 30 Gy/3 fractions, 33 Gy/3 fractions, or 40 Gy/5 fractions using a CyberKnife device (Accuracy Incorporated, Madison, Wisconsin, United States). The primary endpoint was complete AVM obliteration, determined by MRA imaging. Most obliterations were confirmed with diagnostic cerebral angiography. Secondary endpoints were post-radiosurgery hemorrhage and radiation-related necrosis. Kaplan-Meier analysis was used to determine obliteration rates. From 2013 to 2021, 37 patients fitting inclusion criteria were identified (62% male, average age at treatment = 48.88 years). Fifteen (41%) patients had prior treatment (surgery, radiosurgery, embolization) for their AVM, 32 (86%) had AVMs in eloquent locations, 17 (46%) had high-risk features, and 14 (38%) experienced AVM rupture prior to treatment. The average modified radiosurgery-based AVM score (mRBAS) was 1.81 (standard deviation (SD)= 0.52), and the mean AVM volume was 6.77 ccs (SD = 6.09). Complete AVM obliteration was achieved in 100% of patients after an average of 26.13 (SD = 14.62) months. The Kaplan-Meier analysis showed AVM obliteration rates at one, two, and three years to be 16.2%, 46.9%, and 81.1%, respectively. Post-operative AVM rupture or hemorrhage occurred in one (2.7%) patient, after nine months. Radiation necrosis occurred in four (11%) patients after an average period of 17.3 (SD =14.7) months. The SRS dose used in this study is the highest BED of any AVM hypofractionation trial in the published literature. This study suggests that dose-escalated hypofractionated radiosurgery can be a successful strategy for AVMs with acceptable long-term complication rates. Further investigation of this treatment regimen should be performed to assess its efficacy.

Dynamic Contrast Enhanced MR Perfusion and Diffusion-Weighted Imaging of Marrow-Replacing Disorders of the Spine: A Comprehensive Review.

Significant advancements in cancer treatment have led to improved survival rates for patients, particularly in the context of spinal metastases. However, early detection and monitoring of treatment response remain crucial for optimizing patient outcomes. Although conventional imaging methods such as bone scan, PET, MR imaging, and computed tomography are commonly used for diagnosing and monitoring treatment, they present challenges in differential diagnoses and treatment response monitoring. This review article provides a comprehensive overview of the principles, applications, and practical uses of dynamic contrast-enhanced MR imaging and diffusion-weighted imaging in the assessment and monitoring of marrow-replacing disorders of the spine.