Modulating the tumor immune microenvironment with locoregional image-guided interventions.

Cancer immunotherapy has gained significant attention in recent years and has revolutionized the modern approach to cancer therapy. However, cancer immunotherapy is still limited in its full potential due to various tumor immune-avoidance behaviors and delivery barriers, and this is seen in the low objective response rates of most cancers to immunotherapy. A novel approach to immunotherapy utilizes image-guided administration of immunotherapeutic agents directly into a tumor site; this technique offers several advantages, including avoidance of potent toxicity, bypassing the tumor immunosuppressive microenvironment, and higher therapeutic bioavailability relative to systemic drug administration. This review presents the biological rationale for locoregional image-guided immunotherapy administration, summarizes the existing interventional oncology approaches to immunotherapy, and discusses emerging technological advances in biomaterials and drug delivery that could further advance the field of interventional oncology.

Systematic review and meta-analysis of percutaneous transluminal forceps biopsy for diagnosing malignant biliary strictures.

OBJECTIVES: To perform a systematic review and meta-analysis to determine the diagnostic performance of percutaneous transluminal forceps biopsy (PTFB) for differentiating malignant from benign biliary stricture. METHODS: A comprehensive literature search of the PubMed, EMBASE, and Ovid MEDLINE databases was conducted to identify original articles published between January 2001 and January 2021 reporting the diagnostic accuracy of PTFB. A random-effects model was used to summarize the diagnostic odds ratio and other measures of accuracy. RESULTS: Fourteen studies involving 1762 patients met the inclusion criteria and were included in the meta-analysis. The meta-analysis summary estimates of PTFB for diagnosis of malignant biliary strictures were as follows: sensitivity 81% (95% confidence interval [CI], 78-81%); specificity 100% (95% CI, 98-100%); diagnostic odds ratio 85.34 (95% CI, 38.37-189.81). The area under the curve of PTFB was 0.948 in the diagnosis of malignant biliary strictures. The diagnostic sensitivity was higher in intrinsic (85%) than in extrinsic (73%) biliary strictures. The pooled rate of all complications was 10.3% (95% CI, 7.0-14.2%), including a major complication rate of 3.1%. CONCLUSION: These data demonstrate that PTFB is sensitive and highly specific for diagnosing malignancy in biliary strictures. PTFB should be incorporated into future guidelines for tissue sampling in biliary cancer, especially in cases with failed endoscopic management. KEY POINTS: • PTFB had a good overall diagnostic performance for differentiating malignant from benign biliary strictures, with a meta-analysis summary estimate of 81% for sensitivity and 100% for specificity. • PTFB had higher sensitivity for cholangiocarcinoma (85%) than for other cancers (73%). • PTFB had a 100% technical success rate and a 10.3% rate for complications, including a 3.1% rate for major complications.

Appropriateness of Replacing Fluoroscopic Guidance With ECG-Electromagnetic Guidance for PICC Insertion: A Randomized Controlled Trial.

OBJECTIVE. Coupled ECG-electromagnetic (EM) guidance shows promise for use in placement of peripherally inserted central catheters (PICCs) when compared with the classic blind technique. However, ECG-EM guidance has not been appropriately compared with the reference standard of fluoroscopy (FX) guidance. Here, we aimed to compare ECG-EM guidance with FX guidance with regard to the final tip position of PICCs. SUBJECTS AND METHODS. A total of 120 patients (age range, 19-94 years) referred for PICC placement were randomized to the ECG-EM or FX group. All interventions were performed by PICC team members who had the same standardized training and experience. Final tip position was assessed using chest radiography and was classified as optimal, suboptimal, or inadequate requiring repositioning on the basis of the distance from the PICC tip to the cavoatrial junction (CAJ). Statistical analyses were performed using the Mann-Whitney U test for final catheter tip position (mean distance from CAJ) and Fisher and chi-square tests for proportions. RESULTS. PICCs were successfully inserted in 118 patients (53 men and 65 women). Catheter tip positions were optimal or suboptimal in 100% of the FX group and 77.2% of the ECG-EM group. Furthermore, precision of placement was significantly better (p = .004) in the FX group (mean distance from the PICC tip to the CAJ = 0.83 cm) than in the ECGEM group (mean distance from the PICC tip to the CAJ = 1.37 cm). Thirteen (22.8%) of the PICCs placed using ECG-EM guidance, all of which were inserted from the left side, were qualified as inadequate requiring repositioning and required another intervention. CONCLUSION. Our results revealed significant differences in final tip position between the ECG-EM and FX guidance techniques and indicate that ECG-EM guidance cannot appropriately replace FX guidance among unselected patients. However, ECGEM guidance could be considered as an acceptable technique for patients in whom the PICC could be inserted from the right side. TRIAL REGISTRATION. ClinicalTrials.gov NCT03652727.

Factors affecting the success of fallopian tube recanalization in treatment of tubal obstructive infertility.

OBJECTIVE: To examine potential risk factors associated with the success rate following fallopian tube recanalization (FTR) in infertile women with obstruction of the proximal fallopian tube. METHODS: We retrospectively studied patients who underwent FTR for tubal obstructive infertility between January 2016 and December 2018 at the Third Affiliated Hospital of Guangzhou Medical University. FTR was performed using a catheter and guidewire system to clear tubal obstruction. Predictive factors potentially associated with the success rate were assessed by logistic regression. RESULTS: A total of 762 patients were included. Multivariable analysis showed that age (odds ratio [OR] = 2.38, 95% confidence interval [CI]: 1.24-4.58), infertility type (OR = 2.82, 95% CI: 1.36-6.21), history of ectopic pregnancy (OR = 7.87, 95% CI: 4.05-15.81), history of abdominal surgery (OR = 4.30, 95% CI: 2.22-8.60), history of artificial abortion curettage (OR = 4.08, 95% CI: 2.12-8.03), and duration of infertility (OR = 2.03, 95% CI: 1.06-3.85) were independently associated with postoperative tubal patency. CONCLUSIONS: Our findings suggest that risk factors, such as age ≥35 years, secondary infertility, duration of infertility ≥5 years, and histories of ectopic pregnancy, abdominal surgery, and artificial abortion curettage, affect the success rate of FTR. These factors may also predict surgical success in treating tubal obstructive infertility.

Patient radiation dose in percutaneous biliary interventions: recommendations for DRLs on the basis of a multicentre study.

OBJECTIVE: Percutaneous biliary interventions (PBIs) can be associated with a high patient radiation dose, which can be reduced when national diagnostic reference levels (DRLs) are kept in mind. The aim of this multicentre study was to investigate patient radiation exposure in different percutaneous biliary interventions, in order to recommend national DRLs. METHODS: A questionnaire asking for the dose area product (DAP) and the fluoroscopy time (FT) in different PBIs with ultrasound- or fluoroscopy-guided bile duct punctures was sent to 200 advanced care hospitals. Recommended national DRLs are set at the 75th percentile of all DAPs. RESULTS: Twenty-three facilities (9 interventional radiology depts. and 14 gastroenterology depts.) returned the questionnaire (12%). Five hundred sixty-five PBIs with 19 different interventions were included in the analysis. DAPs (range 4-21,510 cGy·cm2) and FTs (range 0.07-180.33 min) varied substantially depending on the centre and type of PBI. The DAPs of initial PBIs were significantly (p < 0.0001) higher (median 2162 cGy·cm2) than those of follow-up PBIs (median 464 cGy·cm2). There was no significant difference between initial PBIs with ultrasound-guided bile duct puncture (2162 cGy·cm2) and initial PBIs with fluoroscopy-guided bile duct puncture (2132 cGy·cm2) (p = 0.85). FT varied substantially (0.07-180.33 min). CONCLUSIONS: DAPs and FTs in percutaneous biliary interventions showed substantial variations depending on the centre and the type of PBI. PBI with US-guided bile duct puncture did not reduce DAP, when compared to PBI with fluoroscopy-guided bile duct puncture. National DRLs of 4300 cGy·cm2 for initial PBIs and 1400 cGy·cm2 for follow-up PBIs are recommended. KEY POINTS: • DAPs and FTs in percutaneous biliary interventions showed substantial variations depending on the centre and the type of PBI. • PBI with US-guided bile duct puncture did not reduce DAP when compared to PBI with fluoroscopy-guided bile duct puncture. • DRLs of 4300 cGy·cm2for initial PBIs (establishing a transhepatic tract) and 1400 cGy·cm2for follow-up PBIs (transhepatic tract already established) are recommended.

Endovascular Treatment of a Dural Arteriovenous Fistula after Cerebral Sinovenous Thrombosis in a Child.

BACKGROUND: Dural arteriovenous fistula (DAVF) is rare in children. Development theories postulate a response to cerebral sinovenous thrombosis (CSVT) or to venous hypertension. The symptoms are highly nonspecific and depend on lesion location. Standard treatment of thrombosis is based on antithrombotic therapy, while the main therapy for DAVF is embolization. CASE REPORT: An 8-year-old boy presented with headache was diagnosed with CSVT and treated with anticoagulant. He developed tinnitus, mental confusion, and lowering of consciousness. Magnetic resonance imaging showed a DAVF draining through a single stenotic venous sinus. Successful endovascular treatment was performed with arterial embolization of multiple feeders and stent and balloon sinus angioplasty. CONCLUSION: Risk factors associated with sinus thrombosis must be always investigated; endovascular treatment is safe and reasonable in a clinical deterioration scenario.

Risk of Radiation-Induced Cataracts: Investigation of Radiation Exposure to the Eye Lens During Endourologic Procedures.

BACKGROUND: Due to new radiobiologic data, the International Commission on Radiological Protection recommends a dose limit of 20 mSv per year to the eye lens. Therefore, the IAEA International Basic Safety Standard and the European council directive 2013/59/EURATOM require a reduction of the annual dose limit from 150 to 20 mSv. Urologists are exposed to an elevated radiation exposure in the head region during fluoroscopic interventions, due to the commonly used overtable X-ray tubes and the rarely used radiation protection for the head. Aim of the study was to analyze real radiation exposure to the eye lens of the urologist during various interventions, during which the patient is in the lithotomy position. MATERIALS AND METHODS: The partial body doses (forehead and apron collar) of the urologists and surgical staff were measured over a period of 2 months. 95 interventions were performed on Uroskop Omnia Max workplaces (Siemens Healthineers, Erlangen, Germany). Interventions were class-divided in less (stage I) and more complex (stage II) interventions. Two dosimeter-types were applied, well-calibrated electronic personal dosimeter Mk2 and self-calibrated thermoluminescent dosimeter-100H (both Thermo Fisher Scientific, Waltham, MA). The radiation exposure parameters were documented using the dose area product (DAP) and the fluoroscopy time. RESULTS: The correlation between DAP and the apron dose of the urologist was in average 0.07 µSv per 1 µGym2. The more experienced urologists yielded a mean DAP of 166 µGym2 for stage I and 415 µGym2 for stage II procedures. The interventionist was exposed with 10 µSv in mean outside the lead apron collar. The mean dose value of the eye lenses per intervention was ascertained to 20 µSv (mean DAP: 233 µGym2). CONCLUSIONS: The study setup allows a differentiated and time-resolved measurement of the radiation exposure, which was found heterogeneous depending on intervention and surgeon. In this setting, ∼1000 interventions can be performed until the annual eye lens dose limit is achieved.

Preoperative biliary drainage associated with biliary stricture after pancreaticoduodenectomy: a population-based study.

BACKGROUND: The rate of preoperative biliary drainage for pancreaticoduodenectomy has been increasing despite most recent evidence that favors avoiding it. Only a few studies have focused on late surgical complications - biliary stricture after pancreaticoduodenectomy and have produced only inconclusive results. We evaluate the role of preoperative biliary drainage in the formation of biliary stricture after pancreaticoduodenectomy. METHODS: The Taiwan National Health Insurance Program is a mandatory health care plan that covers nearly the entire population of 23 million in this country. A retrospective study was conducted to analyze the database compiled by the Taiwan National Health Insurance between January 2000 and December 2011. We included only patients with at least 2 years of follow-up. A cohort of 2,087 patients with preoperative diagnosis of biliary obstruction that underwent pancreaticoduodenectomy was evaluated. RESULTS: A total of 212 (10.1%) of the 2,087 studied patients needed intervention for biliary stricture after pancreaticoduodenectomy. The median time to biliary stricture formation was 15.2 months (range: 1.2-89.7 months). The cumulative biliary stricture rate was 6.9% (1 year), 15.8% (5 years), and 18.5% (10 year). Multivariate analysis showed preoperative biliary drainage (hazard ratio 1.78, 95% CI 1.27-2.50, P = 0.001) associated with biliary stricture after pancreaticoduodenectomy. CONCLUSIONS: Preoperative biliary drainage increases biliary stricture rate after pancreaticoduodenectomy.

Late Coil Migration after Embolization of Cerebral Aneurysms ­ Case Series

Background Coil migration after cerebral aneurysm embolization is a very rare complication. It can take place early or late in the postoperative period, evolving asymptomatic and causing severe neurological deficits. Ruptured aneurysms of anterior communicant artery were the most frequent reported examples in the literature. Case Report We report three cases of patients with unruptured aneurysms treated with coils and remodeling balloon technique. The first case was that of a left posterior communicating artery aneurysm with coil migration to a distal cortical branch of ipsilateral middle cerebral artery (MCA). The patient had mild paresthesia in the arm for a few days. The second one was a fenestrated basilar artery aneurysm with coil migration to the P2 segment of the left posterior cerebral artery. The patient was fully asymptomatic. The third case was a MCA aneurysm with coil migration to the M3 segment. There were no ischemic complications, and all patients underwent a new endovascular procedure. Conclusions Coil migration is a rare but not always severe complication. Antiplatelet agents are recommended even if the coil migration is asymptomatic.

Introdução A migração de coil após embolização de aneurisma cerebral é uma complicação muito rara. Ela pode ocorrer no período pós-operatório tanto precoce quanto tardio, evoluindo assintomático ou causando graves déficits neurológicos. Aneurismas rotos da artéria comunicador anterior foram os exemplos mais frequentes relatados na literatura. Relato de Caso Relatamos três casos de pacientes com aneurismas não rotos tratados com coils e técnica de remodelagem com balão. O primeiro caso foi de um aneurisma de artéria comunicante posterior com migração do coil para um ramo cortical distal da artéria cerebral média (ACM) ipsilateral. A paciente apresentou parestesia leve no braço por alguns dias. O segundo foi um aneurisma de artéria basilar fenestrada com migração de coil para o segmento P2 da artéria cerebral posterior esquerda. O paciente ficou totalmente assintomático. O terceiro caso foi de um aneurisma de ACM com migração do coil para o segmento M3. Não houve complicações isquêmicas, e todos os pacientes foram submetidos a novo procedimento endovascular. Conclusões Migração de coil é uma complicação rara, mas nem sempre grave. Antiagregantes plaquetários são recomendados mesmo se a migração do coil for assintomática.

Preoperative biliary drainage adversely affects surgical outcomes in periampullary cancer: a retrospective and propensity score-matched analysis.

BACKGROUND: The use of preoperative biliary drainage (PBD) for managing patients with periampullary cancer awaiting surgery remains controversial. The impact of PBD status and type on surgical outcomes has not been established, leading to a lack of consensus. We aimed to evaluate the impact of PBD on short-term surgical outcomes in curatively resected periampullary cancer. METHODS: We retrospectively reviewed data from patients undergoing curative periampullary cancer resection. A propensity score-matched analysis was performed to adjust for clinical differences. Univariate and multivariate analyses were performed to determine independent risk factors for complications. RESULTS: The overall complication rate was significantly higher in patients who underwent PBD (P = 0.027). Additionally, complication rates were significantly higher in the endoscopic biliary drainage (EBD) group than in the percutaneous transhepatic biliary drainage (PTBD) group (P < 0.001). After propensity score matching, overall complication rates in patients receiving EBD (P < 0.001) were significantly higher. PBD type and diagnosis were independent risk factors for complications (hazard ratios: 1.927 for EBD; 1.921 for biliary tract cancer). CONCLUSIONS: Preoperative biliary drainage, especially EBD, should not be routinely performed in patients awaiting surgery for periampullary cancer, as it increases the risk of complications.

Computed tomography-guided preoperative localization of small lung nodules with indocyanine green.

Background Small, deep-seated lung nodules and sub-solid nodules are often difficult to locate without marking. Purpose To evaluate the success and complication rates associated with the use of indocyanine green (ICG) to localize pulmonary nodules before resection. Material and Methods This retrospective study was approved by our institutional review board. Informed consent for performing preoperative localization using ICG marking was obtained from all patients. Thirty-seven patients (14 men, 23 women; mean age = 63.1 years; age range = 10-82 years) with small peripheral pulmonary nodules underwent computed tomography (CT)-guided ICG marking immediately before surgery between March 2007 and June 2016. The procedural details and complication rates associated with ICG marking are described. Results The average nodule size and depth were 9.1 mm (range = 2-22 mm) and 9.9 mm (range = 0-33 mm), respectively. Marking was detected at the pleural surface in 35 patients (95%). Three cases of mild pneumothorax (8%), five cases of cough (14%), and one case of mild bloody sputum (3%) with no clinical significance were noted. There were no severe complications. The average duration required to perform the marking was 19.4 min (range = 12-41 min). Conclusion Our results indicate that CT-guided ICG marking is safe and useful for detecting the location of small pulmonary nodules preoperatively.

Bilateral obstruction of bilaterally duplicated collecting systems requiring upper and lower moiety drainage.

A 60-year-old woman with a history of breast cancer presented with bilateral obstruction of bilaterally duplicated renal collecting systems secondary to extrinsic compression from metastatic pelvic lymphadenopathy. Bilateral JJ ureteric stents were inserted, resulting in some improvement of renal function but a failure to normalise completely. Repeat computed tomography demonstrated bilateral duplex collecting systems with persisting obstruction of the undrained moieties. Selective puncture was performed to decompress the obstructed renal moieties for bilateral nephrostomy catheter insertion. This allowed renal function to improve sufficiently for the patient to be discharged and commence chemotherapy. This is the first reported case of bilaterally obstructed partially duplicated collecting systems and it illustrates the importance of recognising anatomical variants to tailor treatment appropriately. It also highlights the important relationship between urology and interventional radiology in the management of such complex patients.

Deep vein thrombosis caused by malignant afferent loop obstruction / 영남의대학술지

Afferent loop obstruction following gastrectomy is a rare but fatal complication. Clinical features of afferent loop obstruction are mainly gastrointestinal symptoms. A 56-year-old female underwent radical total gastrectomy with Roux-en-Y esophagojejunostomy for treatment of advanced gastric cancer. After fourteen months postoperatively, she showed gradual development of edema of both legs. Computed tomography (CT) scan showed disease progression at the jejunojejunostomy site and consequent dilated afferent loop, which resulted in inferior vena cava (IVC) compression. A drainage catheter was placed percutaneously into the afferent loop through the intrahepatic duct and an IVC filter was placed at the suprarenal IVC, and selfexpanding metal stents were inserted into bilateral common iliac veins. With these procedures, sympotms related with afferent loop obstruction and deep vein thrombosis were improved dramatically. The follow-up abdominal CT scan was taken 3 weeks later and revealed the completely decompressed afferent loop and improved IVC patency. Surgical treatment should be considered as the first choice for afferent loop obstruction; however, because it is more immediate and less invasive, non-surgical modalities, such as percutaneous catheter drainage or stent placement, can be effective alternatives for inoperable cases or risky patients who have severe medical comorbidities.

EXTRACORPOREAL SHOCK WAVE LITHOTRIPSY AND ENDOSCOPIC URETERAL STENT PLACEMENT IN AN ASIAN SMALL-CLAWED OTTER (AONYX CINEREA) WITH NEPHROLITHIASIS.

Urolithiasis is a significant disease concern in Asian small-clawed otters (Aonyx cinerea), with over 60% of captive animals affected. Bilateral ureteral stent placement, using endoscopic and fluoroscopic guidance, and extracorporeal shock wave lithotripsy (ESWL) were performed as salvage procedures in a 13-yr-old intact female Asian small-clawed otter following a 7-yr history of nephrolithiasis and progressive renal insufficiency. Following the procedure, radiographs revealed a slight shifting of urolith position, although a decrease in urolith mass was not observed. As a result of declining quality of life related to severe osteoarthritis, the otter was euthanized 5 wk after the procedure. While this treatment approach was unsuccessful in this case, the technique was clinically feasible, so ESWL and ureteral stent placement may remain a consideration for other individuals of this species presented earlier in the course of this disease.

Evaluation of the reliability of measurements in cephalograms generated from cone beam computed tomography.

OBJECTIVE: The purpose was to compare angular and linear measurements generated in digital cephalometric radiographs and cephalograms synthesized from three-dimensional images. METHODS: Twenty-six individuals (12 men and 14 women) with mean age of 26.3 years were selected. Digital cephalometric radiographs and CBCTs were taken on the same day. The images were imported and analyzed on Dolphin Imaging V.10.5 software, which synthesized cephalograms in perspective projection and magnification of 9.7%. A single observer marked the points and repeated the procedure with an interval of time of ten days to evaluate intraexaminer error. In the statistical analysis paired Student's t test was used to establish the correlation between the measurements. RESULTS: The angular measurements GoGn.SN and IMPA, which involved the Gonial point (Go) and the linear measurements that involved the lips presented significant difference (p < 0.05). The other measurements presented good correlation. CONCLUSIONS: The measurements in the synthesized cephalograms proved to be reliable.

Evaluation of the reliability of measurements in cephalograms generated from cone beam computed tomography

OBJECTIVE: The purpose was to compare angular and linear measurements generated in digital cephalometric radiographs and cephalograms synthesized from three-dimensional images. METHODS: Twenty-six individuals (12 men and 14 women) with mean age of 26.3 years were selected. Digital cephalometric radiographs and CBCTs were taken on the same day. The images were imported and analyzed on Dolphin Imaging V.10.5 software, which synthesized cephalograms in perspective projection and magnification of 9.7%. A single observer marked the points and repeated the procedure with an interval of time of ten days to evaluate intraexaminer error. In the statistical analysis paired Student's t test was used to establish the correlation between the measurements. RESULTS: The angular measurements GoGn.SN and IMPA, which involved the Gonial point (Go) and the linear measurements that involved the lips presented significant difference (p < 0.05). The other measurements presented good correlation. CONCLUSION: The measurements in the synthesized cephalograms proved to be reliable.

OBJETIVO: comparar medidas angulares e lineares geradas em radiografias cefalométricas digitais e cefalogramas sintetizados a partir de imagens tridimensionais. MÉTODOS: selecionou-se 26 indivíduos (12 do sexo masculino e 14 do feminino), com média de idade de 26,3 anos, que realizaram no mesmo dia as radiografias cefalométricas digitais e tomografia computadorizada de feixe cônico. As imagens foram importadas e analisadas no software Dolphin Imaging V.10.5, que sintetizou cefalogramas com projeção perspectiva e magnificação de 9,7%. As marcações dos pontos foram realizadas por um único observador e repetidas com um intervalo de tempo de 10 dias para avaliação do erro intraexaminador. Para a análise estatística, utilizou-se o teste t de Student pareado para estabelecer a correlação entre as medidas. RESULTADOS: as medidas angulares GoGn.SN e IMPA, que envolviam o ponto Gônio (Go), e as medidas lineares que envolviam os lábios, apresentaram diferença significativa (p < 0,05). As outras medidas apresentaram boa correlação. CONCLUSÃO: as medições nos cefalogramas sintetizados mostraram-se confiáveis.

CT-guided percutaneous drilling is a safe and reliable method of treating osteoid osteomas.

Computed tomography (CT)-guided percutaneous drilling is an alternative for osteoid osteoma treatment. This study aims to evaluate the remodeling of the drill orifice. The success rate and complications were also recorded and compared with other treatment methods. Fifteen patients with an average age of fourteen years (ranging from 4 to 25) submitted to CT-guided percutaneous drilling between 2003 and 2009 were retrospectively analyzed according to clinical and radiological criteria. Fourteen cases showed complete alleviation of pain one week after surgery. No relapse was detected even in the subject who continued complaining of pain. All patients were treated with a day-hospital regimen and were discharged with partial weight bearing. Total weight bearing was allowed after one month, and sports were allowed after consolidation, which occurred in all but one case after the third month. One patient, who did not follow our medical advice, returned to sports activities after two weeks and experienced a fracture as a result. Atrophy of the vastus lateralis muscle developed after the procedure in another patient. Our case series suggests that this method is reliable and safe. The level of complexity is comparable with other minimally invasive percutaneous procedures. The cost is low because there is no need to buy probes or other equipment. The negative points include weakening of the bone and the logistical problem of assembling the orthopedic surgeon, radiologist, and anesthesiologist in the tomography room.

Interventional radiography in management of high-flow arteriovenous malformation of maxilla: report of a case.

Arteriovenous malformations are extremely rare conditions in that can result from abnormalities in the structure of blood vessels, which may be potentially fatal. A 30-year-old female patient visited our hospital with a complaint of swelling on the right maxillary posterior gingiva along with the large port-wine stain on right side of face. On clinical examination, the swelling was compressible and pulsatile. Radiographic examination revealed a lytic lesion of maxilla. Diagnostic angiography revealed a high-flow arteriovenous malformation of maxilla which was treated by selective transarterial embolization of maxillary artery using polyvinyl alcohol particles.

Radiation exposure and its reduction in the fluoroscopic examination and fluoroscopy-guided interventional radiology

Radiation exposure during fluoroscopy has been of consistent interest because fluoroscopy is used not only for diagnostic purposes such as upper gastrointestinal series but for many minimally-invasive treatments in various clinical fields. In 2000, the International Commission on Radiological Protection published the important report about the avoidance of radiation injuries from medical interventional procedures, and this report defined harm during fluoroscopic-guided interventional procedure and how to reduce the radiation dose of patients and staff. Two aspects of fluoroscopy exposure differ from other types of medical radiation exposure, including computed tomography. One is that the entrance surface dose during an interventional procedure may be very high, so the deterministic effects of radiation such as skin or corneal injury should be emphasized more than stochastic effects such as cancer risk. The other is that the variation in radiation exposure is great for the same kind of procedure, so it is very difficult to generate a reference level for the radiation dose. Therefore, it is necessary to develop a guideline for the use of fluoroscopy through a nationwide survey about irradiation during fluoroscopic examinations and fluoroscopy-guided intervention procedures. In conclusion, radiation exposure by fluoroscopic guided intervention is not negligible, and the practitioner should always aim to reduce radiation exposure during interventional procedures.

Interventional radiography in management of high-flow arteriovenous malformation of maxilla: report of a case

Arteriovenous malformations are extremely rare conditions in that can result from abnormalities in the structure of blood vessels, which may be potentially fatal. A 30-year-old female patient visited our hospital with a complaint of swelling on the right maxillary posterior gingiva along with the large port-wine stain on right side of face. On clinical examination, the swelling was compressible and pulsatile. Radiographic examination revealed a lytic lesion of maxilla. Diagnostic angiography revealed a high-flow arteriovenous malformation of maxilla which was treated by selective transarterial embolization of maxillary artery using polyvinyl alcohol particles.