Pipeline embolization device as a standalone curative approach for recurrent sigmoid sinus DAVF.

Dural arteriovenous fistulas (dAVFs) can occur as complications after surgical procedures, especially following the resection of meningiomas near the dural sinus. This case report presents a 74-year-old male who developed a recurrent sigmoid dAVF following meningioma resection. Initially treated with transvenous embolization and middle meningeal artery embolization, the dAVF recurred with worsening clinical symptoms. Conventional treatment options, including sinus sacrifice and transarterial embolization, were unsuitable due to the critical role of the patient's dominant right sigmoid sinus in cerebral venous drainage. Consequently, a reconstructive approach was employed using a pipeline embolization device (PED) construct. The PED successfully occluded the dAVF while preserving the function of the sigmoid sinus. A follow-up angiogram confirmed stable occlusion and normalization of intracranial venous drainage. This case underscores the potential of flow diversion as a viable treatment option for dAVFs, particularly in scenarios where preserving venous sinus function is paramount.

Parasagittal dural arteriovenous fistulas.

BACKGROUND: The majority of studies on parasagittal dural arteriovenous fistulas (DAVFs) have been limited to case reports or case series, and they are frequently reported alongside true superior sagittal sinus (SSS) DAVFs. Because of the selective bias present in the reporting of dispersed small numbers of parasagittal DAVFs, the results of each study may influence the findings. As a result, we present a large sequential cohort of parasagittal DAVFs from our institution spanning a 20-year period. METHODS: This study was a retrospective analysis involving 80 patients with parasagittal DAVFs who were hospitalized at a single medical center from 2002 to 2022. We explore their clinical manifestations, angioarchitecture, clinical and radiographic outcomes. RESULTS: We identified 80 patients with 85 parasagittal DAVFs. The cohort consisted of 69 men and 11 women, with a M ± SD age of 50.5 ± 11.1 years. Seventy-six patients underwent trans-arterial embolization (TAE), two underwent surgery, and two received conservative treatment. Immediate complete occlusion was achieved in 74 cases (94.9%). Fifty (96.2%) patients were cured, with no recurrence detected on final follow-up imaging. One patient died 6 months after the final subtotal occlusion, while the other patients experienced improvement or resolution of clinical symptoms following treatment. CONCLUSIONS: These lesions carry a high risk of hemorrhage and nonhemorrhagic neurological deficits. In our series, TAE achieved a high cure rate for these lesions, with no major complications reported.

Coil-assisted ethanol embolization of traumatic arteriovenous fistulas: a 10-year retrospective study.

Purpose: This study aimed to evaluate the efficacy and safety of ethanol embolization in treating traumatic arteriovenous fistulas (TAVFs). Materials and methods: From March 2012 to April 2020, 42 consecutive patients (29.9 ± 15.1 years, range: 3-68 years) with peripheral TAVFs underwent ethanol embolization. All patients underwent clinical and imaging follow-ups (40.0 ± 25.9 months, range: 3-90 months). The mean time to onset of symptoms after trauma was 5.4 ± 5.9 months (range: 0.5-30 months). Among the patients, 27 (64.3%) reported that the TAVFs occurred after blunt trauma, 10 (23.8%) presented after penetrating trauma (with 4 patients involving penetration by infusion indwelling needles), and 3 (7.1%) had a history of surgery. Treatment effects, devascularization rates, and complications were evaluated at follow-ups conducted at 1-3 month intervals. Results: Seventy-one embolization procedures were performed, with a mean of 1.6 ± 0.7 procedures per patient. Thirty-four patients received coil-assisted ethanol embolization. Absolute ethanol was used in all procedures, with an average volume of 7.1 ± 4.2 ml per procedure (range: 1-18 ml); 28 patients (28/42, 66.7%) received coil embolization in 36 procedures (36/71, 50.7%). Upon re-examination, 39 patients (92.9%) achieved 100% devascularization; of these, 29 patients (74.4%) with Schobinger stage II TAVFs improved to stage I or became asymptomatic. Overall, 30 cases (66.7%) achieved a complete response, while the other 12 cases (33.3%) showed a partial response. In addition, no major complications were observed postoperatively, apart from minor complications. Conclusions: Coil-assisted ethanol embolization can effectively manage TAVFs with an acceptable risk of mild complications.

Risk prediction models for autogenous arteriovenous fistula failure in maintenance hemodialysis patients: A systematic review and meta-analysis.

BACKGROUND: The aim of this study was to systematically retrieve and evaluate published risk prediction models for autogenous arteriovenous fistula (AVF) failure post-formation in maintenance hemodialysis (MHD) patients, with the goal of assisting healthcare providers in selecting or developing appropriate risk assessment tools and providing a reference for future research. METHODS: A systematic search of relevant studies was conducted in PubMed, Web of Science, Cochrane Library, CINAHL, Embase, CNKI, Wanfang Database, VIP Database, and CBM Database up to February 1, 2024. Two researchers independently performed literature screening, data extraction, and methodological quality assessment using the Prediction Model Risk of bias (ROB) Assessment Tool. RESULTS: A total of 4869 studies were identified, from which 25 studies with 28 prediction models were ultimately included. The incidence of autogenous AVF failure in MHD patients ranged from 3.9% to 39%. The most commonly used predictors were age, vein diameter, history of diabetes, AVF blood flow, and sex. The reported area under the curve (AUC) ranged from 0.61 to 0.911. All studies were found to have a high ROB, primarily due to inappropriate data sources and a lack of rigorous reporting in the analysis domain. The pooled AUC of five validation models was 0.80 (95% confidence interval: 0.79-0.81), indicating good predictive accuracy. CONCLUSION: The included studies indicated that the predictive models for AVF failure post-formation in MHD patients are biased to some extent. Future research should focus on developing new models with larger sample sizes, strict adherence to reporting procedures, and external validation across multiple centers.

Comparative Volumetric Analyses Following Bevacizumab Therapy for a Patient With Concomitant Glioblastoma, Meningioma, and Dural Arteriovenous Fistula: A Case Report and Review of Literature.

Given that glioblastoma (GBM), meningioma (Mg), and dural arteriovenous fistula (dAVF) represent angiogenic diseases mainly caused by vascular endothelial growth factor (VEGF), bevacizumab (Bev) is expected to be effective against these diseases. We report a patient with concomitant GBM, Mg, and dAVF who was treated with neoadjuvant Bev, resulting in a reduction in the volume of GBM along with an improvement of clinical symptoms. An 85-year-old male presented with aphasia, gait disturbance, and dementia. Magnetic resonance imaging (MRI) showed a ring-enhanced intra-axial tumor with perifocal edema in the left temporal lobe, a dura-attached extra-axial tumor at the left sphenoid ridge, and dAVF at the left transverse-sigmoid sinus. Due to the age of the patient and low Karnofsky Performance Status (KPS) score, pharmacotherapy with a single dose of Bev was chosen over surgical resection. Three days after the Bev administration, aphasia and gait disturbance had dramatically improved. Volume reduction rates at one and five months after three administrations of Bev were 0.34% and 95.9% for GBM and 13.7% and 6.8% for meningioma, respectively. No significant change in dAVF was seen on digital subtraction angiography (DSA) during Bev therapy. VEGF concentration in GBM is known to be the highest among all types of brain tumors, including meningioma. VEGF might not play a pivotal role in the pathogenesis of dAVF. Based on this evidence from the present rare case with concomitant GBM, meningioma, and dAVF, responsiveness to Bev might depend on the level of VEGF expression.

Stereotactic radiosurgery for anterior cranial fossa dural arteriovenous fistulas.

OBJECTIVE: Anterior cranial fossa (ACF) dural arteriovenous fistulas (DAVFs) are notoriously malignant vascular abnormalities, and their drainage into the cortical vein poses a high risk of intracranial hemorrhage (ICH). Stereotactic radiosurgery (SRS) is increasingly seen as an alternative to microsurgery or embolization for the treatment of DAVFs; however, researchers have yet to report on its applicability to ACF DAVFs. This paper summarizes the authors' experience in the use of SRS for ACF DAVFs. The authors' objective was to gain a preliminary overview of SRS outcomes in the treatment of ACF DAVFs. METHODS: This retrospective study examined all patients who underwent SRS for ACF DAVFs at a single academic medical center between November 2000 and November 2023. Demographic data, DAVF characteristics, and clinical outcomes were obtained from medical records. RESULTS: A total of 12 patients diagnosed with ACF DAVFs were treated using SRS. One patient was lost to follow-up. The mean age was 54.8 years and men comprised 82% of the cohort. The most common presenting symptoms included headache (n = 5), ocular symptoms (n = 3), seizure (n = 2), anosmia (n = 1), and tinnitus (n = 1). Two patients were asymptomatic. Four patients (36%) initially presented with ICH. Nine patients exhibited DAVF Cognard type IV, and 2 patients exhibited Cognard type III. DAVF obliteration in 7 of the 11 patients (64%) was confirmed by brain MR angiography (n = 4) or digital subtraction angiography (n = 3). No post-SRS episodes of ICH were reported. Most of the patients (10 of 11) reported improvements in clinical symptoms. CONCLUSIONS: SRS appears to be a viable alternative treatment for ACF DAVFs, particularly for patients who are not suitable candidates for surgery or those with an unfavorable angioarchitecture.

Is there an association between arteriovenous fistulas and axillary artery aneurysms? A report of two cases.

INTRODUCTION: Axillary artery aneurysms are rare vascular conditions that can present with various clinical manifestations, including neurological deficits and vascular compromise. While the underlying pathophysiology remains complex and multifactorial, potential associations with trauma, arteriovenous fistula formation, and atherosclerosis have been reported. PRESENTATION OF CASE: Two male patients, aged 33 and 38, with a history of kidney transplantation and previous arteriovenous fistula (AVF) presented with symptoms of upper limb ischemia and neurological compromise. Imaging revealed large axillary artery aneurysms. Open surgical repair was performed for both cases. Two weeks after discharge, one patient showed good pronation and supination with mildly limited extension. The other patient's wrist drop gradually improved with physiotherapy. DISCUSSION: Multifactorial pathophysiology encompassed altered blood flow dynamics, inflammation, and the underlying vascular pathology. Chief complaints and prior vascular interventions contributed. Open surgical repair was preferred to endovascular approaches, achieving favorable outcomes. CONCLUSION: Axillary artery aneurysms in patients with a history of AVF are rare but potentially serious complications. The cases highlight the complexity of axillary artery aneurysms and the need for careful evaluation and surgical intervention This strategy is crucial to prevent potential complications and optimize patient outcomes. Further research is needed to elucidate the precise pathophysiology and the potential association between AVF and the subsequent development of axillary artery aneurysms. Increasing awareness among surgeons could enable earlier detection of aneurysms, thereby reducing the risk of complications.

Embolization of an epidural arteriovenous fistula of the sacral nerve root with a neural tube defect: A case report.

INTRODUCTION AND IMPORTANCE: Rarely, epidural arteriovenous fistula (AVF) of the sacral neural root may be associated with neural tube defects. CASE PRESENTATION: A 46-year-old man presented with progressive weakness and numbness in both lower extremities. On physical examination, both lower extremities only had Grade III muscle strength. MRI revealed extensive dilated veins along the spinal cord, edema of the spinal cord, lipomyelomeningocele and tethering of the spinal cord. Angiography revealed an epidural AVF at the sacral neural root with intradural venous drainage. Endovascular treatment (EVT) was performed. First, a microcatheter accessed the AVF; then, another microcatheter coiled around the feeding artery near the fistula to establish the "pressure cooker" effect; finally, the AVF was obliterated by casting Onyx via the first microcatheter. After EVT, the patient's symptoms improved immediately. Postoperative computed tomography confirmed the presence of defective sacral bone. Based on the patient's physical examination and imaging findings, a neural tube defect with a tethered cord and a lipomyelomeningocele were confirmed. Two months later, the patient recovered well and could walk. The follow-up MR image revealed a nearly normal spinal cord. CLINICAL DISCUSSION: Microsurgical resection is difficult because of the deep location of such an AVF. EVT by casting Onyx can be a feasible option. To avoid Onyx reflux, the 'pressure cooker' technique can be helpful for obliterating such an AVF. CONCLUSION: On the basis of this case report, EVT can be effective for epidural AVFs of the sacral neural root in select cases.

Efficacy of ultrasonography and color-Doppler for early prediction of hemodialysis arteriovenous fistula unassisted maturation.

BACKGROUND: Arteriovenous fistula (AVF) failure is a prevalent concern for patients with end-stage kidney disease on hemodialysis. Recognizing the efficacy of ultrasound Doppler in post-operative AVF evaluation, this study sought to discern the predictive capabilities of various ultrasonographic and color-Doppler metrics for early AVF outcomes. METHODS: This single-center, prospective cohort study spanned 1 year and, post ethical clearance, included all patients who underwent native AVF creation surgery and were subsequently referred for standard post-operative ultrasound Doppler assessment. Parameters such as fistula size, cephalic vein area and diameter, and AVF flow velocity and rates were assessed on post-operative day 2, week 2, and week 6. These initial findings were juxtaposed with later outcomes to determine unassisted AVF results. RESULTS: Of the initial cohort of 40 patients, 75% encountered AVF failure, whereas 25% realized successful unassisted AVF maturation. A notable observation was the significant variance in AVF flow rates as early as post-operative day 2. A threshold of >246 ml/min was indicative of successful unassisted AVF maturation, leading to a sensitivity of 80% and a specificity of 70%. Although the cephalic vein diameter on post-operative day 2 lacked a robust association with AVF outcomes, a cut-off of >3.4 mm, when combined with flow rate testing, augmented the cumulative sensitivity to 92%. CONCLUSION: Ultrasound Doppler stands out as a valuable quantitative imaging modality, adept at prognosticating AVF outcomes from as early as post-operative day 2. In particular, a flow rate exceeding 246 ml/min and a cephalic vein diameter surpassing 3.4 mm are salient indicators for the early prediction of successful AVF outcomes.

Trends in venous diameter and brachial artery volume flow of AVF in 12 weeks postoperatively.

OBJECTIVE: To explore the trends of venous diameter and brachial artery volume flow (VF) in 12 weeks after arteriovenous fistula (AVF) and the influence of preoperative arterial diameter on this trend. Our goal was to clarify the maturation process within 12 weeks after AVF surgery. METHODS: Clinical data of 257 patients with end-stage renal disease who had their first radial-cephalic AVF established at our institution from February 1, 2023 to February 1, 2024 were included. The patients were divided into group A (radial artery diameter <1.5 mm), group B (radial artery diameter 1.5-2.0 mm), and group C (radial artery diameter >2.0 mm) according to the preoperative radial artery diameter. After AVF surgery, the artery and vein diameter, brachial artery VF were recorded at 1 day, 2 weeks, 4 weeks, 6 weeks, 8 weeks, 10 weeks and 12 weeks. RESULTS: 1. The venous diameter and brachial artery VF of AVF showed an upward trend, and increased significantly in 1 day-6 weeks postoperatively (P < 0.05),especially between 1 day and 2 weeks, while no significant difference in the increases at 6-12 weeks. 2. Groups B and C were in line with the above trend, whereas the patients in group A showed best growth in 2-4 weeks postoperatively. 3. The natural maturation rates of AVF in groups B and C were significantly better than that of group A at all postoperative time (P＜0.05). CONCLUSION: The AVF was in a developmentally dominant stage at 6 weeks postoperatively, with 1 day-2 weeks being particularly prominent. The postoperative natural maturation rate of AVF with arteries diameter of<1.5 mm was low, the direct use of such arteries to establish AVF need careful consideration.

Application of prophylactic flow restriction in brachiocephalic arteriovenous fistulas. / 预防性限流在肱动脉-å¤´é™è„‰å† ç˜˜ä¸­çš„åº”ç”¨.

OBJECTIVES: To investigate the effects of prophylactic flow restriction for brachiocephalic arteriovenous fistula on postoperative high-flow-related complications and patency rate in patients undergoing hemodialysis. METHODS: Clinical data of patients with end-stage renal disease who underwent brachiocephalic arteriovenous fistula surgery for hemodialysis from February 2017 to May 2022 in Department of Nephrology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine were retrospectively analyzed. During surgery, a 4-5 mm vascular suture loop was placed around the vein near the anastomosis as a flow restriction device in 43 patients (flow restriction group), while 42 patients did not receive the prophylactic flow restriction ring (control group). All patients were followed up for 1 to 5 years. The incidence rates of complications related to the hemodialysis access pathway, including distal ischemia syndrome, the formation of arteriovenous fistula aneurysms, high-flow congestive heart failure, and cephalic arch stenosis, were compared between the two groups. The natural blood flow rate of the arteriovenous fistula, anastomosis size, the internal diameter of the vein near the anastomosis,primary patency rate, assisted primary patency rate, and secondary patency rate of the arteriovenous fistula, were also evaluated and compared in two groups. Logistic regression analysis was used to investigate the factors affecting arteriovenous fistula patency rates, as well as the impact of the flow-restricting ring on postoperative factors. RESULTS: Ultrasound measurements showed that the internal diameter of the vein at the site of the flow restriction ring in the flow restriction group was (3.7±0.6) mm three months postoperatively, which was significantly smaller than the internal diameter of the narrowest part of the vein near the anastomosis in the control group (4.1±1.0 mm, t=－2.416, P<0.01). The postoperative anastomotic diameter and natural blood flow rate of the arteriovenous fistula in the flow restriction group were both significantly lower than those in the control group (both P<0.05). Furthermore, the incidence rates of various complications in the flow restriction group were significantly lower than those in the control group (all P<0.05). At 6, 12, and 24 months postoperatively, the primary patency rate and assisted primary patency rate in the flow restriction group were significantly higher than those in the control group (both P<0.05), while there was no significant difference in secondary patency rates between the two groups (P>0.05). Binary logistic regression analysis indicated that age, diabetes, and natural blood flow rate of the arteriovenous fistula at 3 months postoperatively were independent risk factors for primary patency rate, while the flow restriction for brachiocephalic arteriovenous fistula was an independent protective factor for primary patency rate (all P<0.05). The application of flow restriction was negatively correlated with anastomotic diameter at 6 and 12 months, natural arteriovenous fistula blood flow, and the incidence rates of cephalic arch stenosis and aneurysm formation (all P<0.05). CONCLUSIONS: The prophylactic constriction during brachiocephalic arteriovenous fistula surgery in patients undergoing hemodialysis can limit the size of the anastomosis and postoperative arteriovenous fistula blood flow, reducing complications such as cephalic arch stenosis and high-flow heart failure, and increasing primary patency rates of arteriovenous fistula and delay the reintervention of the fistula.

Traumatic arteriovenous fistula of the superficial temporal artery caused by massive subcutaneous hematoma prompting surgical removal and endovascular treatment in a patient with neurofibromatosis type 1.

Background: Neurofibromatosis type 1 (NF-1) is often characterized by vascular disorders related to vessel vulnerability that can lead to unfavorable outcomes. Here, we describe a case of NF-1 complicated with a massive subcutaneous hematoma posing a risk of visual impairment for which rapid decompression and a subsequent less invasive approach result in a favorable outcome. Case Description: A 40-year-old woman with NF-1 presented with a massive left subcutaneous temporal hematoma following a mild head contusion. Four days after hospitalization, the hematoma increased in size and severely compressed the left eye, prompting immediate hematoma removal to preserve visual function. Immediately after the hematoma removal, a superficial temporal arteriovenous fistula was found on the digital subtraction angiography and embolized by the endovascular procedure. Her visual acuity was preserved, and no bleeding recurrence was observed throughout the follow-up. Conclusion: Surgical hematoma removal followed by endovascular treatment was effective in preserving visual function. Since vessel fragility is characteristic of patients with NF-1, it should be kept in mind that vascular complications may lead to serious clinical outcomes. In certain NF-1 cases, less invasive treatments for vascular abnormalities may be preferable.

[Clinical Thermography for the Management of Hemodialysis Vascular Access].

The arteriovenous fistula (AVF) represents the favorite vascular access in individuals with chronic kidney disease (CKD). Because AVF is a guarantee of survival for these patients, proper surgical packing and a timely follow-up program is crucial. Although a good objective examination of the limb site of FAV provides useful information both in planning the fistula surgery and in its surveillance and monitoring, it is now well established that the advent of instrumental diagnostics (ultrasonography, digital angiography, Angio-TC, MRI) has contributed significantly to improving primary and secondary patency of FAV and early diagnosis of vascular access complications. In this area, clinical thermography, a noninvasive and nondestructive diagnostic technique for assessing minute surface temperature differences, has shown good potential for the assessment of AVF. In fact, thermographic analysis of a limb site of AVF shows an increase in temperature at the site of the anastomosis and along the course of the arterialized vein. In this article we report our experience on the use of thermography in preoperative evaluation and postoperative surgical packing of an AVF. Further studies could validate the use of clinical thermography as a diagnostic technique to be used in the field of hemodialysis vascular accesses.

Intravenous leiomyomatosis in the inferior vena cava and right atrium with pulmonary benign metastasizing leiomyoma secondary to a pelvic arteriovenous fistula: A case report and literature review.

BACKGROUND: To report the diagnosis and treatment of a rare disease of intravenous leiomyomatosis (IVL) originating from the uterus, growing in the inferior vena cava (IVC) and extending into the right atrium (RA) associated with a pelvic arteriovenous fistula (AVF). This is the first reported case of IVL in the IVC and RA with pulmonary benign metastasizing leiomyoma (PBML) secondary to a pelvic AVF despite the use of GnRH agonists in a nonmenopausal woman. CASE PRESENTATION: The patient was a 50-year-old premenopausal woman with a history of surgical resection for and antiestrogen conservative drug for pulmonary benign metastasizing leiomyoma (PBML) 5 years. The patient nevertheless developed IVL in the IVC, internal iliac vein and RA accompanied by AVF. Vaginal ultrasound combined with echocardiography and computerized tomographic venography imaging assists in the diagnosis of IVL combined with AVF, with histopathology and immunohistochemistry ultimately confirming the diagnosis. The patient ultimately was performed with a combination of hysterectomy, bilateral adnexectomy, and resection of tumors in the IVC and RA without cardiopulmonary bypass and sternotomy. CONCLUSION: BML may be difficult to control with incomplete removal of the uterus and ovaries even with the use of antiestrogenic medications, and medically induced AVF resulting from fibroid surgery may accelerate this process and the development of IVL.

Anatomical Feasibility of Percutaneous Arteriovenous Fistula Formation in Korea.

INTRODUCTION: Currently, there are two types of percutaneous arteriovenous fistula (pAVF) formation systems approved by the FDA: Ellipsys and WavelinQ. Although these systems are already in use in Europe or the United States, they have not been approved for use in Korea yet. For this reason, this study aimed to check anatomical feasibility of these systems for Korean population prior to their actual use. METHODS: Consecutive patients who received ultrasound vein mapping for arteriovenous fistula formation from June 2021 to June 2022 were included. The anatomical feasibility of each system was confirmed according to the manufacturer's instructions for use (IFU). RESULTS: Upper extremity ultrasonography was performed for a total of 83 patients to determine their feasibility for pAVF formation. Of these patients, 65.1% were feasible for pAVF formation with appropriate deep communicating vein (DCV) and outflow. Among them, 57.8% were feasible for the Ellipsys system and 54.2% were feasible for the WavelinQ system. Most patients who were infeasible for pAVF formation had a DCV of small size. Ulnar vessels were more suitable than radial vessel for WavelinQ (54.2% vs 33.7%, P-value = .012). The most common reason for not meeting the criteria was a small vein size at the access site. CONCLUSIONS: More than half of all patients were feasible for pAVF formation in this study. Ellipsys had a higher feasibility than WavelinQ, although they showed no significant difference in the feasibility. If these devices are imported into Korea, it will be a good opportunity for many patients to reduce the surgical burden and create AVFs more easily through these procedures.

Reliable Stenosis Detection Based on Thrill Waveform Analysis Using Non-Contact Arteriovenous Fistula Imaging.

Hemodialysis therapy is an extracorporeal circulation treatment that serves as a substitute for renal function. In Japan, patients receive this efficient four-hour treatment, three times per week, allowing them to maintain a social life nearly equivalent to that of healthy individuals. Before the treatment, two punctures are performed to establish extracorporeal circulation, and a high blood flow rate is essential to ensure efficient therapy. Specialized blood vessels created through arteriovenous fistula (AVF) surgery are utilized to achieve high blood flow rates. Although the AVF allows safe and efficient dialysis treatment, AVF stenosis leads to a serious problem in dialysis. To early detect this abnormal blood flow, auscultation and palpation methods are widely used in hospitals. However, these methods can only provide qualitative judgment of the AVF condition, so the results cannot be shared among other doctors and staff. Additionally, since the conventional methods require contact with the skin, some issues require consideration regarding infection and low reproducibility. In our previous study, we proposed an alternative method for auscultation using non-contact optical imaging technology. This study aims to construct a reliable AVF stenosis detection method using Thrill waveform analysis based on the developed non-contact device to solve the problem with the contact palpation method. This paper demonstrates the performance validation of the non-contact imaging in the normal AVF group (206 total data, 75 patients, mean age: 69.1 years) and in the treatable stenosis group (107 total data, 17 patients, mean age: 70.1 years). The experimental results of the Mann-Whitney U test showed a significant difference (p=0.0002) between the normal and abnormal groups, which indicated the effectiveness of the proposed method as a new possible alternative to palpation.

A Case of Traumatic Splenic Arteriovenous Fistula Treated by Transcatheter Arterial Embolization.

Transcatheter arterial embolization (TAE) has increasingly replaced surgery for treating solid organ injuries, including the spleen, due to its minimally invasive approach. Studies show only a 3% splenectomy rate after TAE, despite a 10% incidence of missed vascular injuries in the American Association for the Surgery of Trauma (AAST) grade III splenic injuries on initial computed tomography (CT) scans. However, there's a lack of high-quality studies recommending specific CT follow-up intervals after non-operative management (NOM) of splenic injuries or guidelines for initiating treatment in cases of pseudoaneurysms or arteriovenous fistulas (AVFs). Here, we discuss the case of a 44-year-old man who presented with a splenic injury due to a motor vehicle accident. The splenic injury was AAST-spleen grade III, but because there was no evidence of extravascular leakage or AVF formation, NOM was selected. CT on the fifth day showed a pseudoaneurysm and an AVF, for which TAE was performed on the seventh day, preserving most of the parenchyma of the spleen with no complications. The indications for NOM as a treatment strategy for splenic injury are expanding, but since the 2018 revision of the AAST grading, the grade changes depending on the presence or absence of vascular injury, but in some cases, it is difficult to determine the presence or absence of active bleeding by CT findings. In fact, it has been reported that more than 25% of vascular lesions do not show up on CT, although CT has good sensitivity in detecting active bleeding, and the rate of NOM failure is higher in AAST grade III and above, so early angiography is likely to be useful. Splenic AVF may present with few symptoms in the early stages but may present with extrahepatic portal hypertension in the late stages, and patients may present to the hospital with symptoms such as abdominal pain and diarrhea. TAE is often the treatment of choice in traumatic cases, and the extent of embolization is important in the balance between preserving splenic function and completing treatment. The shift towards conservative management of splenic trauma may increase the occurrence of splenic AVFs. Transcatheter coil embolization of segmental branches has been effective in treating posttraumatic splenic AVFs, preserving splenic immune function and reducing risks linked to surgery and splenectomy.

Diagnostic Pitfalls of the Bleeding Origin after a Percutaneous Renal Biopsy: A Report of Two Cases.

A percutaneous renal biopsy (PRB) is a standard procedure for diagnosing renal disease, but can cause bleeding complications. Bleeding after a PRB can be classified as early- or late-onset, depending on the timing of the onset of the bleeding symptoms (<24 h or ≥24 h). We herein report two patients who experienced bleeding complications: one experienced early-onset bleeding from the 12th subcostal artery, and the other experienced late-onset bleeding from an arteriovenous fistula between a branch of the renal artery and renal vein. In both cases, the origin of the bleeding vessel was misjudged during the first examination. We discuss the diagnostic pitfalls of the origin of bleeding after a PRB and propose measures to avoid falling such pitfalls.