Early experience of thalidomide therapy for high-grade peripheral and facial arteriovenous malformations.

BACKGROUND: Arteriovenous malformations (AVMs) are developmental defects in the vascular system with abnormal connections between arteries and veins. A minority of AVMs are characterized by aggressive growth and continue to proliferate despite maximal surgical and interventional therapy. We report our outcomes with the use of thalidomide as the only UK specialist center adopting this novel approach for the management of AVMs refractory to conventional therapy. METHODS: This was a retrospective case series which included only complex and proliferative AVM lesions (Schobinger grade III and IV). All patients prescribed thalidomide on a compassionate basis between September 2006 and August 2022 after attempts at embolosclerotherapy without satisfactory response were reviewed. RESULTS: Eleven patients were included in our study. The median total duration of thalidomide use was 10 months. Two thirds of patients with pain (six of nine) reported an improvement, three quarters reported a reduction in swelling (six of eight) and all who presented with bleeding reported improvement in overall volume or frequency (four of four). Over the study period, 45% achieved a non-proliferative state with no further target vessel demonstrable on angiography. Mild, tolerable side effects such as fatigue were common (73%). There was only one major adverse reaction (neutropenia) necessitating cessation of therapy. CONCLUSIONS: We can conclude that thalidomide is able to reduce the symptom burden for patients with complex and proliferative AVMs that were refractory to established treatment modalities. Adverse effects are common, but the benefit achieved from taking thalidomide in otherwise treatment resistant cases outweighs the risks, most of which are manageable.

Histopathological analysis of vascular malformations.

OBJECTIVE: To propose and develop a histopathological criteria to help diagnose vascular malformations. METHODS: All patients who underwent surgical resection and had a confirmed histopathological diagnosis of vascular malformations from 01 March 2018-26 February 2020 were included. A criteria based on 10 parameters was developed to help diagnose vascular malformations. Discrepancies between clinical and histopathological diagnosis were evaluated. RESULTS: A total of 18 cases were identified. There was a discrepancy between the clinical diagnosis and the initially reported histopathological diagnosis in 16 cases (88.9%). This was reduced to 7 (38.9%) and 6 cases (33.3%) with first and second time revised histopathological analysis using proposed criteria. CONCLUSIONS: The discrepancy between clinical and histopathological diagnoses of vascular malformations has highlighted the requirement of an agreed criteria for histopathologists to help formulate their diagnosis. The proposed criteria may be used as a guide in addressing this and guide treatment and improve clinical practice.

Efficacy and safety of embolo-sclerotherapy of arteriovenous malformations with foam sodium tetradecyl sulphate.

BACKGROUND: To evaluate the efficacy and safety of embolo-sclerotherapy (EST) particularly with foamed sclerotherapy in the treatment of arteriovenous malformations (AVMs). METHODS: All patients with AVM who underwent interventional therapy i.e. EST from January 1st, 2015 - December 31st, 2019 were identified through a prospective database. Types of AVM were classified according to Schobinger's classification. The outcome measures assessed efficacy and complications. The former was divided into four groups: no response, mild response, moderate response, and complete response. Complications were defined as any tissue or functional damage, distal embolization or tissue reaction. Continuous variables were compared using analysis of variance (ANOVA) F test and discrete variables were analysed using χ2 tests. P<0.05 was considered significant. RESULTS: A total of 65 patients were included. There was no statistical difference amongst the volume of foam STS 3% or alcohol used across all types of AVM. Overall, majority of patients (86.2%) reported some degree of improvement following interventional therapy. Six (9.2%) patients experienced complications including necrosis and amputation. The proportions of complication were significantly different across the categories (P=0.009). Patients with type III AVM seemed to report more complications than others. CONCLUSIONS: Foam sclerotherapy was clinically effective and safe for patients with AVM. This study showed that foam sclerotherapy with STS 3% provided a safe and efficacious alternative sclerosant to ethanol despite it was not often reported to be used to treat AVM. However, a combination of embolic agents is likely required to treat type IV AVMs.

Efficacy and safety of foam sclerotherapy with sodium tetradecyl sulfate as preferred sclerosant of venous malformations based on experience from a single specialist center.

OBJECTIVE: We have assessed the efficacy and safety of interventional therapy for venous malformations (VMs), with foam sclerotherapy as the treatment of choice according to our experience at a single specialist center. METHODS: All the patients with VMs who had undergone interventional therapy (ie, embolo-sclerotherapy and/or open surgery) from January 1, 2015 to December 31, 2019 were identified through a prospective database. The VM types were classified according to the Puig classification. The outcome measures assessed included the efficacy and complications. The former was divided into four groups: no response, mild response, moderate response, and complete response. The complications were defined as any tissue or functional damage, distal embolization, or tissue reaction. The continuous variables were compared using the analysis of variance F test, and discrete variables were analyzed using the χ2 tests. P values < .05 were considered statistically significant. RESULTS: A total of 207 patients were included. Puig type I lesions were significantly less likely to have received foam sclerotherapy using sodium tetradecyl sulfate (STS) 3% (P ≤ .001) and more likely to have been surgically excised (P ≤ .001). At the patient's first procedure during the study period, the volumes of foam STS 3% were significantly different across all types of VM (P ≤ .001). The patients with type I VMs had received a lower volume of STS 3% compared with those with type II and III VMs. The efficacy outcome categories were significantly different across all types of VMs (P ≤ .001). Overall, only 14 patients (6.8%) had reported no improvement in efficacy, and 38 patients (18%) had not attended follow-up. Therefore, 154 patients (74.8%) had experienced some form of efficacious outcome. Ten patients (4.8%) had developed complications such as hematoma, thrombophlebitis, and ulceration. The incidence of complications differed significantly across the categories (P = .030), with more complications reported for those with type I VMs. CONCLUSIONS: We found that intervention with foam sclerotherapy using STS 3% is clinically effective and safe for patients with VMs and was most successful for those with Puig type I and II VMs.

Early follow-up quality of life and mental health of patients with congenital vascular malformations cared for in a multi-disciplinary specialist centre.

OBJECTIVE: The study aimed to evaluate the early follow-up quality of life (QoL), pain and mental health of patients with congenital vascular malformation (CVM) from a variety of treatment options. METHODS: All patients with CVM who received care and had follow-up between February 1st 2018 and January 31st 2020 were included. The health-related QoL, pain, and mental health were assessed with RAND Health Care 36-Item Short Form Survey (SF-36), visual analogue score for pain (VAS-P) and Hospital Anxiety and Depression Scale (HADS). Paired t-test was used for all analyses. p < .05 were considered significant. RESULTS: In total, 110 patients with a mean age of 36.9 years were included in this study. In all patients following care, significant improvement was found in the bodily pain domain of SF-36 and VAS-P (both p = .01). This was largely driven by high-flow vascular malformation patients who responded better to embolo-sclerotherapy, which revealed significant improvement in the bodily pain domain of SF-36 (p = .002) and VAS-P (p = .02). Patients who received supportive treatment only reported significant improvement in mental health (p = .004) and social functioning (p = .03) domains of SF-36. Meanwhile, patients treated with embolo-sclerotherapy reported significant improvement only in VAS-P (p = .02). CONCLUSIONS: This study concluded that the effects of care on early follow-up QoL, pain and mental health of patients with CVM were heterogenous. Future research should therefore, include larger sample size and longer term follow-up to understand the various factors that affect the QoL and mental health of these patients, as well as the holistic approaches to manage them.

Quality of life and mental health of patients with vascular malformations in a single specialist center in the United Kingdom.

OBJECTIVE: Patients with vascular malformations suffer from chronic debilitating symptoms that have been shown to contribute negatively to their quality of life (QoL) and mental health. Despite this, the current literature evaluating the QoL and mental health of patients with vascular malformations remains scarce. Our aim was to evaluate the QoL and mental health of patients with vascular malformations. METHODS: We prospectively analyzed the validated health-related QoL (HRQoL) questionnaires: the RAND Health Care 36-Item Short Form Survey (SF-36), Hospital Anxiety and Depression Scale (HADS), and visual analogue score for pain reported by 253 patients with vascular malformations in a specialist center of vascular anomalies in the UK over 2 years. RESULTS: Patients with vascular malformations reported significantly poorer SF-36 scores in all domains compared with the UK general population. Patients with low-flow vascular malformations and arteriovenous malformations reported little variations in SF-36, HADS, and visual analogue score for pain scores. No significant association was found between age and any of the health-related QoL scores, other than the physical functioning in SF-36. Female patients reported significantly lower physical and social functioning of SF-36 and worse HADS-Depression than their male counterparts. Patients with syndromic vascular malformations reported significantly lower SF-36 scores in role-physical, role-emotional and bodily pain than nonsyndromic vascular malformations. CONCLUSIONS: This study concluded that patients with vascular malformations reported worse QoL than the UK general population. Therefore, the assessment and management of QoL and mental health should be incorporated into the overall treatment strategies of patients with vascular malformations.

Incidence of major complications from embolo-sclerotherapy of head and neck vascular malformations in a single specialist centre.

OBJECTIVE: Current data on the nature and rate of major complications for embolo-sclerotherapy (EST) of vascular malformations are scarce. However, even fewer studies focus on vascular malformations specific to the head and neck, which confer an increased specific risk of airway compromise, neurologic and ophthalmologic injury. More understanding is required surrounding the type and incidence of complications to improve treatment planning and informed consent. Therefore, this study aimed to review major complications secondary to EST of head and neck vascular malformations over a 5-year period in a single specialized multidisciplinary centre for vascular anomalies. METHODS: All interventions were decided by the multidisciplinary team. Demographic, procedural and complication data between 1st January 2013 and 31st December 2017 were prospectively documented in a dedicated database and analysed. EST of high-flow vascular malformations (HFVMs) was performed by selective catheter angiography or direct injection, and by direct injection only for low-flow vascular malformations (LFVMs). Major complications were defined as any tissue or functional damage caused by direct injection, distal embolization or tissue reaction and were decided by the multidisciplinary team. RESULTS: Forty-eight patients (median age of 35 years; range of 14-70 years; 18 men and 30 women) had 100 EST procedures for head and neck vascular malformation. Of these, 14 patients had EST for HFVM and 34 patients for LFVM, total 43 and 57 procedures, respectively. Overall, five patients with HFVM developed major complications from EST when compared with two patients with LFVM (p = 0.0167). Two patients required pre-emptive tracheostomy due to risk of post-operative airway compromise. Overall, seven (14.6%) patients experienced major complication from EST. In the HFVM group, major complications from EST occurred in five patients; four cases of tissue ulceration and necrosis (two needed debridement, one healed with resultant fibrosis that impeded speech and one resolved spontaneously) and one post-procedural airway compromise requiring tracheostomy. Meanwhile, in the LFVM group, major complications occurred in two patients; one case of severe necrosis involving the alar cartilage, lip and cheek requiring debridement and reconstruction under plastics and one simple cellulitis. No patients sustained stroke or vision impairment. CONCLUSIONS: EST is relatively safe for head and neck vascular malformations in a high-volume experienced centre. Our major complication rate of 14.6% per patient (35.7% for HFVM; 5.9% for LFVM) or 7% per procedure (11.6% for HFVM; 3.5% LFVM) compares favourably with published data from other centres. These data will improve treatment planning and informed consent for EST for both HFVM and LFVM of the head and neck.

Giant parapharyngeal high-flow arteriovenous malformation causing airway compromise: emergency embolo-sclerotherapy via an endovascular-only approach.

Head and neck arteriovenous malformations are the commonest extracranial vascular malformations but demonstrate a unique challenge in the limited available surgical options secondary to their intimate association to vital structures. We present a case of middle-aged female patient who presented with threatened upper-airway obstruction and bleeding secondary to a slowly enlarging parapharyngeal arteriovenous malformations. She was treated with an endovascular-only approach with the proximal arteriole branches selectively undergoing embolo-sclerotherapy with an optimal radiological and clinical outcome. We also demonstrate the utility of elective tracheostomy prior to intervention.

Illuminating the nidus: The role of FDG PET/CT in high flow arteriovenous vascular malformations.

The appropriate identification and localization of a nidus of a high flow arteriovenous malformation is crucial to guide targeted interventional therapy. However, the nidus of a complex or previously treated HFAVM can be difficult to non-invasively demonstrate on magnetic resonance imaging alone. We describe a unique case of a 56-year-old female with a complex high flow arteriovenous malformation in which we demonstrated the feasibility of fluorodeoxyglucose positron emission tomography/computed tomography to non-invasively delineate the nidus which subsequently guided successful targeted interventional therapy.

Single Center Experience of Sirolimus Therapy in Head and Neck Low-flow Vascular Malformations.

OBJECTIVE: Recently, studies have shown that sirolimus is clinically efficacious in the treatment of some low-flow vascular malformations (LFVM). This study aimed to assess the efficacy and safety of sirolimus in treating complex head and neck (H&N) LFVM that were challenging and/or refractory to standard treatment. METHODS: Each patient had baseline and 6-months assessments consisting of clinical history and examination, quality of life (QoL) questionnaires, laboratory investigations, MRI and medical photography. Patients were followed up 1-week and then 1-monthly for 6-months. Wilcoxon signed-rank test was used to compare pre-and 6-months treatment in all 8 domains of RAND 36-Item Short Form Health Survey (SF-36), hospital anxiety and depression scale (HADS), and visual analog score for pain (VAS-P). P < 0.05 was considered significant. RESULTS: Seven patients (median age 43 years, range 23-65 years) were recruited. Six patients completed the six-months course of therapy with 1 patient withdrawing due to intolerable side effects. All six patients reported reduction of swelling with and without other symptom improvement related to the vascular malformations while on treatment. However, at 1-month review after discontinuation of sirolimus, 5 patients reported return of initial symptoms. Overall, patients demonstrated an improvement in QoL six-months treatment but there was no statistical significance (P > 0.05) in all 8 domains of SF-36, HADS and VAS-P. Five patients demonstrated a minimum 10% decrease in lesion size six-months treatment (median 21%, range 13-40%). A Wilcoxon signed-rank test showed that sirolimus treatment did elicit a statistically significant change in lesion size in either direction (Z = -1.992, P = 0.046). The most common side effects found were dyslipidaemia (n-4) and mouth ulcers (n = 2). CONCLUSION: In our preliminary experience, sirolimus is effective and safe in treating patients with complex H&N LFVM. This provides an alternative treatment where standard treatment is challenging and/or refractory.

Patient radiation exposure from embolo-sclerotherapy of peripheral vascular malformations.

OBJECTIVE: Embolo-sclerotherapy (EST) is the mainstay therapy for peripheral vascular malformations that involves the exposure of patients to ionizing radiation. We analyzed the radiation exposure to patients from EST of peripheral vascular malformations during a 5-year period in a single specialist center. METHODS: All patients who had undergone EST at a single specialist center for peripheral vascular malformations from January 1, 2013 to January 8, 2018 were identified from a prospectively collected database. Data collection included basic demographics, procedure date, anatomic site, type of vascular malformations, and procedural details. Radiation exposure, measured as the dose-area product (DAP) and fluoroscopy time, of all patients who had undergone EST during the study period were retrospectively reviewed. Statistical analysis was performed using the Mann-Whitney U and Kruskal-Wallis tests for comparison between subgroups. P < .05 was considered statistically significant. RESULTS: A total of 237 patients (median age, 30 years; range, 1-73 years) had undergone 419 EST sessions during the study period. Of the 237 patients, 61 (25.7%) had had arteriovenous malformations (AVMs) and had undergone 140 EST sessions (33.4%) and 176 (74.3%) had had venous and lymphatic malformations and had undergone 279 EST sessions (66.6%). Patients with AVMs had undergone a median of 2 procedures (range, 1-13) compared with a median of 1 (range, 1-6) for venous and lymphatic malformations within the study period. The median DAP for the single and cumulative EST for peripheral vascular malformations was 1.26 Gycm2 (range, 0.00-698.36 Gycm2) and 1.91 Gycm2 (range, 0.00-1300.24 Gycm2), respectively. The median fluoroscopy time for single and cumulative EST was 19 seconds (range, 1-3846 seconds) and 30 seconds (range, 1-5843 seconds), respectively. Significantly greater patient radiation exposure, in DAP and fluoroscopy time, was measured for single and cumulative EST for AVMs compared with venous and lymphatic malformations (P < .01 for both; Mann-Whitney U test). A significant difference in DAP but not fluoroscopy time was found when the anatomic areas of vascular malformations were compared. CONCLUSIONS: Patient radiation exposure for EST for peripheral vascular malformations, measured in DAP and fluoroscopy time, appeared to be generally less than that reported for endovascular arterial and deep venous interventions. However, some patients with peripheral vascular malformations received relatively high radiation doses. Further studies to investigate the risk factors and long-term side effects of radiation exposure in these patients and strategies to reduce these are required.

Incidence of major complication following embolo-sclerotherapy for upper and lower extremity vascular malformations.

OBJECTIVE: The current literature on the major complications of embolo-sclerotherapy of upper and lower extremity vascular malformations is scarce. Evaluating and understanding the rates and types of potential major complications of embolo-sclerotherapy of vascular malformations help treatment planning and informed consent. Therefore, this study reviewed major complications following embolo-sclerotherapy of all upper and lower extremity vascular malformations in a single specialized multidisciplinary vascular malformation center over a 5-year period. METHODS: All patients with vascular malformations underwent multidisciplinary directed intervention. Demographic, procedural, follow-up, and complication data were collected prospectively in a dedicated database, and reviewed retrospectively. Major complications for upper and lower extremity vascular malformations from 1 January 2013 to 31 December 2017 were analyzed. All embolo-sclerotherapies of high-flow vascular malformations (HFVMs) were performed under selective catheter angiography and direct injection, but low-flow vascular malformations (LFVM) with direct injection only. Major complications were defined as any tissue or functional damage caused by direct injection, distal embolization, or tissue reaction. RESULTS: Seventy patients (median age of 25 years; 44 males and 26 females) had 150 embolo-sclerotherapy procedures for upper extremity vascular malformation. Of these, 28 patients had embolo-sclerotherapy for HFVM and 42 patients for LFVM; total 78 and 72 procedures, respectively. A total of 107 patients (median age of 26 years; 42 males and 65 females) had 160 embolo-sclerotherapy interventions for lower extremity vascular malformations. Of these, 18 patients had embolo-sclerotherapy for HFVM and 89 patients for LFVM; total of 30 and 130 procedures, respectively. The overall major complication rates following embolo-sclerotherapy of upper and lower extremity vascular malformations were 14.3% and 4.7%, respectively (P = 0.030). In the upper extremity HFVM group, major complications from embolo-sclerotherapy occurred in five patients; three ischemic fingers requiring amputation and two skin ulcerations. Meanwhile, in the upper extremity LFVM group, major complications occurred in five patients; one median nerve injury requiring nerve grafting and hand therapy, one hand contracture requiring tendon release, and three skin ulcerations. There was only one major complication, which was cellulitis in the lower extremity HFVM group. In the lower extremity LFVM group, major complications occurred in four patients; two skin ulcerations, one cellulitis, and one deep vein thrombosis. CONCLUSIONS: Embolo-sclerotherapy is relatively safe for upper and lower extremity vascular malformations in a high-volume experienced center where our major complication rates were 14.3% and 4.7%, respectively, which compare favorably or similar to those reported in most recent literature. These outcomes will direct treatment strategies to avoid local and systemic toxic complications in the upper and lower extremity, for both HFVM and LFVM, and to improve informed consent.

Novel use of arterial spin labelling in the imaging of peripheral vascular malformations.

We present a novel use of arterial spin labelling (ASL), a MRI perfusion technique, to assess a high-flow, peripheral vascular malformation (PVM), specifically a large arteriovenous malformation in the left forearm of a 20-year-old female. While there has been experience with ASL in the assessment of intracranial vascular malformations, there has been no known use of ASL in the evaluation of PVMs. We also discuss the potential benefits and limitations of ASL in the imaging of PVMs. The promising results from this case warrant further research on ASL in the investigation of PVMs.

Emerging importance of molecular pathogenesis of vascular malformations in clinical practice and classifications.

Vascular malformations occur during early vascular development resulting in abnormally formed vessels that can manifest as arterial, venous, capillary or lymphatic lesions, or in combination, and include local tissue overdevelopment. Vascular malformations are largely caused by sporadic somatic gene mutations. This article aims to review and discuss current molecular signaling pathways and therapeutic targets for vascular malformations and to classify vascular malformations according to the molecular pathways involved. A literature review was performed using Embase and Medline. Different MeSH terms were combined for the search strategy, with the aim of encompassing all studies describing the classification, pathogenesis, and treatment of vascular malformations. Major pathways involved in the pathogenesis of vascular malformations are vascular endothelial growth factor (VEGF), Ras/Raf/MEK/ERK, angiopoietin-TIE2, transforming growth factor beta (TGF-ß), and PI3K/AKT/mTOR. These pathways are involved in controlling cellular growth, apoptosis, differentiation, and proliferation, and play a central role in endothelial cell signaling and angiogenesis. Many vascular malformations share similar aberrant molecular signaling pathways with cancers and inflammatory disorders. Therefore, selective anticancer agents and immunosuppressants may be beneficial in treating vascular malformations of specific mutations. The current classification systems of vascular malformations, including the International Society of the Study of Vascular Anomalies (ISSVA) classification, are primarily observational and clinical, and are not based on the molecular pathways involved in the pathogenesis of the condition. Several molecular pathways with potential therapeutic targets have been demonstrated to contribute to the development of various vascular anomalies. Classifying vascular malformations based on their molecular pathogenesis may improve treatment by determining the underlying nature of the condition and their potential therapeutic target.

Successful Repair of a Vasculopathic Aneurysmal Brachial Artery in a Patient with Type 1 Neurofibromatosis.

Vasculopathy is a well-recognized abnormality associated with neurofibromatosis type 1(NF1) and may cause stenoses, aneurysms, and arteriovenous malformations. We report a challenging case of a woman with NF1, who presented with spontaneous rupture of a brachial aneurysm around her right elbow, on a background of previous debulking and soft tissue reconstructive surgery in the same arm. She underwent successful delayed reconstruction of the brachial artery using an autologous great saphenous vein graft.

Ten-year single-centre experience with type II endoleaks: Intervention versus observation.

Our objective was to determine the relative merits of intervention or observation of type II endoleaks (T2Ls). A retrospective analysis was performed on 386 infra-renal endovascular aneurysm repair (IR-EVAR) patients from 2006 to 2015. Annual surveillance imaging of patients undergoing EVAR at our centre were analysed, and all endoleaks were subjected to a multidisciplinary team meeting for consideration and treatment. In the 10-year time frame, 386 patients (79.5±8.7 years) underwent an IR-EVAR. Eighty-one patients (21.0%) developed a T2L and intervention was undertaken in 28 (34.6%): 17 (60.7%) were treated via a transarterial approach (TA) and 11 (39.3%) using the translumbar approach (TL). Fifty-three patients (65.4%) with T2Ls were managed conservatively. Patients who received T2L treatment had a greater proportion of recurrent T2Ls than patients who were conservatively managed ( p=0.032). T2Ls associated with aneurysmal growth were more resistant to treatment than those where there was no change or a decrease in aneurysm size during follow-up (0.033). There was no significant difference in the TA and TL approach with respect to endoleak repair success ( p=0.525). Treatment of a T2L did not confer a survival advantage compared to conservative management ( p=0.449) nor did the choice of either the TA or TL approach ( p=0.148). Our study suggests the development of a T2L associated with aneurysm growth may represent an aggressive phenotype that is resistant to treatment. However, this did not lead to an increased risk of mortality over follow-up. Neither a transarterial nor a translumbar approach to treating a T2L conferred superiority.

A staged approach to treating oropharyngeal venous malformation.

We presented a staged approach to treating oropharyngeal venous malformation in Jehovah Witness patient.

Spontaneous sphenopalatine pseudoaneurysm: recurrent epistaxis in a patient with cryptogenic vasculopathy.

We present a unique case of recurrent epistaxis secondary to a spontaneous sphenopalatine artery aneurysm in a young woman. This was investigated with an external carotid artery angiogram and subsequently treated successfully with endovascular embolisation of the aneurysm.

CT signal heterogeneity of abdominal aortic aneurysm as a possible predictive biomarker for expansion.

OBJECTIVE: There is a need for prognostic biomarkers for risk assessment of small abdominal aortic aneurysm (AAA). Since CT textural analysis of tissue is a recognized feature of adverse biology and patient outcome in other diseases, we investigated it as a possible biomarker in small AAA. METHODS: Fifty consecutive patients (46-men, 4-woman, median-age 75 y, range 56-85) with small AAA (3-5.5 cm) under surveillance undergoing serial ultrasound were prospectively recruited and assessed at baseline with CT texture analysis (CTTA) and 18F-Fluorodeoxyglucose positron emission tomography (18F-FDG-PET). We followed forty patients (36-men, 4-woman, median-age=74 y, range 60-85, participation rate=80% for 1 year. For each axial image, CTTA using the filtration-histogram technique was carried out using a software algorithm that selectively extracts texture features of different coarseness (fine, medium and coarse) and intensity variation. Standard-deviation (SD) and kurtosis (K) at each feature-scale were measured. The maximum standardized uptake value (SUVmax) of 18F-FDG in each axial image of the AAA was also measured with corrections for blood pool 18F-FDG activity to assess AAA metabolic activity. Specificity, sensitivity, and c-statistics were calculated with 95% confidence intervals for prediction of significant AAA expansion (≥2 mm) by CTTA measures before and after adjusting for clinical variables. RESULTS: The median aneurysm expansion at 12 months was 2.0 mm, (IQR 0.0-4.0). Coarse texture SD correlated inversely with AAA SUVmax (rs=-0.456, P=0.003). Medium coarse texture K correlated significantly with future AAA expansion adjusted for baseline size (rs=0.343, P=0.030). AAA SUVmax correlated inversely with AAA expansion corrected for baseline size (rs=-0.383, P=0.015). Medium texture K was a strong predictor of significant AAA expansion (area under the Receiver-operating-characteristic (ROC) curve was 0.813) after adjusting for clinical variables. CONCLUSION: We have shown evidence that CT signal heterogeneity measurements in small aortic aneurysm may be considered as a risk stratification tool in future prospective studies to identify aneurysms at risk of significant expansion. CT textural data appears to reflect AAA metabolism measured by PET.

A novel technique for inferior vena cava filter extraction.

Inferior vena cava (IVC) filters are used to protect against pulmonary embolism in high-risk patients. Whilst the insertion of retrievable IVC filters is gaining popularity, a proportion of such devices cannot be removed using standard techniques. We describe a novel approach for IVC filter removal that involves snaring the filter superiorly along with the use of flexible forceps or laser devices to dissect the filter struts from the caval wall. This technique has used to successfully treat three patients without complications in whom standard techniques failed.