Virtual Injection Software Reduces Radiation Exposure and Procedural Time of Prostatic Artery Embolization Performed with Cone-Beam CT.

PURPOSE: To evaluate the impact of virtual injection software (VIS) use during cone-beam computed tomography (CT)-guided prostatic artery embolization (PAE) on both patient radiation exposure and procedural time. MATERIALS AND METHODS: This institutional review board (IRB)-approved comparative retrospective study analyzed the treatment at a single institution of 131 consecutive patients from January 2020 to May 2022. Cone-beam CT was used with (Group 1, 77/131; 58.8%) or without VIS (Group 2, 54/131, 41.2%). Radiation exposure (number of digital subtraction angiography [DSA] procedures), dose area product (DAP), total air kerma (AK), peak skin dose (PSD), fluoroscopy time (FT), and procedure time (PT) were recorded. The influences of age, body mass index, radial access, and use of VIS were assessed. RESULTS: In bivariate analysis, VIS use (Group 1) showed reduction in the number of DSA procedures (8.6 ± 3.7 vs 16.8 ± 4.3; P < .001), DAP (110.4 Gy·cm2 ± 46.8 vs 140.5 Gy·cm2 ± 61; P < .01), AK (642 mGy ± 451 vs 1,150 mGy ± 637; P = .01), PSD (358 mGy ± 251 vs 860 mGy ± 510; P = .001), FT (35.6 minutes ± 15.4 vs 46.6 minutes ± 20; P = .001), and PT (94.6 minutes ± 41.3 vs 115.2 minutes ± 39.6, P = .005) compared to those in Group 2. In multivariate analysis, AK, PSD, FT, and PT reductions were associated with VIS use (P < .001, P < .001, P = .001, and P = .006, respectively). CONCLUSIONS: The use of VIS during PAE performed under cone-beam CT guidance led to significant reduction in patient radiation exposure and procedural time.

[Advances in risk factors and early imaging assessment of canine impaction].

The canines play an important role in both the esthetics and function of the human body. The maxillary canines has the highest prevalence of impaction in the entire dentition, except for the third molars. Once canine impaction occurs, it can lead to the conditions such as root resorption of adjacent teeth, occlusal function interference and esthetic problems. Moreover, the treatment of canine impaction is time consuming and difficult, and it often requires multi-disciplinary involvement. Therefore, the early diagnosis and treatment of canine impaction is an urgent problem in orthodontic treatment. The etiology of canine impaction is complex and its early development is highly insidious. To assist orthodontists in the early diagnosis and treatment of canine impaction, this review summarizes and discusses the relevant risk factors associated with maxillary and mandibular canine impaction, and the commonly used radiographic assessment methods.

Comparative evaluation of mutagenic effects of two cone-beam computed tomography in oral mucosa cells.

BACKGROUND: This pilot study aimed to evaluate the mutagenic effects in cells of the oral mucosa after exposure to two different cone beam computed tomography (CBCT). METHODS: Eighteen adults were submitted to the different CBCT (Carestream CS8100 3D and I-CAT). The cells were collected immediately before the CBCT exposure and 10 days later, when the material was placed on a slide and stained using the Feulgen/Fast Green technique. Microscopic analysis counted micronuclei and other nuclear alterations, which are indicative of cytotoxicity such as pyknosis, karyolysis, karyorrhexis, and binucletion. 2000 cells were analyzed. The statistical analysis was performed with the Wilcoxon Signed-Rank test to compare the frequency of cellular alterations, and the Mann-Whitney U test to compare different CBCTs, both with a significance level of 5%. RESULTS: There was no statistically significant difference in the micronucleated cell count before and after the exposition to the ionizing radiation from I-CAT (p = .298) and CS8100 3D (p = .203) A significate increase of pyknosis (p < .001), karyolysis (p < .001), karyorrhexis (p < .001), and binucletion (p < .001) were noted on I-CAT CBCT. There was no statistically significant difference in cellular alterations in CS8100 3D CBCT. CONCLUSION: Despite the increase in micronuclei after exposure, this study indicates that there is no evidence of genotoxicity. On the other hand, the I-CAT CBCT produced cytotoxic effects.

Middle meningeal artery embolization using cone-beam computed tomography augmented guidance in patients with cancer.

PURPOSE: The purpose of this study was to evaluate the safety and efficacy of middle meningeal artery embolization (MMAE) performed under cone-beam computed tomography (CBCT) augmented guidance in patients with cancer. MATERIALS AND METHODS: Eleven patients with cancer (seven women, four men; median age, 75 years; age range: 42-87 years) who underwent 17 MMAEs under CBCT with a combination of particles and coils for chronic subdural hematoma (SDH) (n = 6), postoperative SDH (n = 3), or preoperative embolization of meningeal tumor (n = 2) from 2022 to 2023 were included. Technical success, fluoroscopy time (FT), reference dose (RD), kerma area product (KAP) were analyzed. Adverse events and outcomes were recorded. RESULTS: The technical success rate was 100% (17/17). Median MMAE procedure duration was 82 min (interquartile range [IQR]: 70, 95; range: 63-108 min). The median FT was 24 min (IQR: 15, 48; range: 21.5-37.5 min); the median RD was 364 mGy (IQR: 37, 684; range: 131.5-444.5 mGy); and the median KAP was 46.4 Gy.cm2 (9.6, 104.5; range: 30.2-56.6 Gy.cm2). No further interventions were needed. The adverse event rate was 9% (1/11), with one pseudoaneurysm at the puncture site in a patient with thrombocytopenia, which was treated by stenting. The median follow-up was 48 days (IQR; 14, 251; range: 18.5-91 days]. SDH reduced in 11 of 15 SDHs (73%) as evidenced by follow-up imaging, with a size reduction greater than 50% in 10/15 SDHs (67%) . CONCLUSION: MMAE under CBCT is a highly effective treatment option, but appropriate patient selection and careful consideration of potential risks and benefits is important for optimal patient outcomes.

Incidental findings in cone beam computed tomography volumes: Calcified head-and-neck atheromas detected during dental evaluation.

PURPOSE: Atheromas can be detected incidentally in routine dental cone beam computed tomography (CBCT) images. This study aims to assess prevalence and risk factors associated with these vascular lesions. MATERIALS AND METHODS: The maxillofacial CBCTs of 458 subjects were evaluated and divided into 4 groups based on the presence of calcified atheroma: subjects with no calcified atheroma, subjects with intracranial calcified atheroma (ICA), subjects with extracranial calcified atheroma (ECA), and subjects exhibiting combined lesions. Age, sex, medical conditions, family history, and size were documented. Analysis of variance followed by a multiple comparison test was used for data satisfying parametric test assumptions. Chi-squared tests were used to assess categorical data. The Spearman Rho test was used to assess the correlation between the incidence of calcified atheroma and subjects' medical condition. RESULTS: Of the 458 CBCTs evaluated, 29.90% presented with calcified atheroma. Calcified atheroma prevalence was significantly higher in older patients versus younger patients (p = 0.004) and in males compared to females (p = 0.004). Males were more likely to have the combination of ICA and ECA, whereas females were more likely to have ICA alone (p ≤ 0.040). Patients with calcified atheroma were significantly more likely to have a history of hyperlipidemia (p = 0.001), hypertension (p = 0.001), and myocardial infarction/coronary artery diseases (p = 0.001). Overall, patients exhibiting both intracranial and extracranial lesions were more likely to have cardiovascular risk factors (p = 0.001). CONCLUSION: Incidentally detected calcified atheromas in CBCTs are common. Subjects with combined atheroma lesions are at higher risk for cardiovascular disease. The diagnosis of incidental calcified atheromas in CBCT's warrants early referral to medical specialists, especially if there is no medical history of existing cardiovascular disease.

Is it necessary to remove bone-impacted teeth? A retrospective study.

BACKGROUND: In clinical practice, it is risky to extract bone-impacted teeth and they're prone to a variety of complications, such as pathological fracture, adjacent tooth fracture, maxillary sinus perforation, and so on, making it difficult for clinicians to decide whether to extract them. PURPOSE: In order to illustrate our opinions on the possibility of extracting full third molars (M3), 360 examples of complete third molars were analyzed in this study. MATERIALS AND METHOD: We investigated 2189 patients, and 261 of them provided CBCT images of 360 teeth. assessing the degree of second molar(M2) root absorption in connection to age, impacted relationship, contact part, calculating the odds ratio (OR) and 95% confidence interval using the Logistic regression analysis equation. RESULT: Bone-impacted M3 occurred in 11.92% (261/2189) of patients with "impacted teeth" diagnoses. There was a significant difference between the occurrence of M2ERR and the contact parts (P value<0.001), and only the type of vertical impaction differed significantly from Level 3 (P < 0.05). CONCLUSIONS: 1) M3 should be removed if root resorption has not occurred in M2. 2) Root resorption is more likely to occur when M3 crown and M2 apical contact. 3) Enough experience, precise preoperative assessment can reduce the dangers to a minimum.

Management of Multiple Idiopathic Root Resorption in a Rheumatoid Arthritis Patient: A Case Report with 4-year Follow-up.

Cervical root resorption is a rare destructive disease that originates from the external cervical root surface. It has a multifactorial etiology. Cervical root resorption may affect several teeth and its treatment can be complicated due to the size, location, and extension of the resorptive defect. Rheumatoid arthritis is a chronic inflammatory autoimmune disease that has systemic effects. The objective of this article was to report a rare case of multiple idiopathic cervical resorptions in a patient with rheumatoid arthritis. A 52-year-old male patient with a 20-year history of rheumatoid arthritis was diagnosed with multiple idiopathic cervical resorptions through cone-beam computed tomography (CBCT) and clinical examination. All known causes for cervical resorption were ruled out after a detailed anamnesis. This report details inflammation due to rheumatoid arthritis as a possible cause of idiopathic cervical resorption. The systemic alterations wrought by rheumatoid arthritis could be related to the etiopathogenesis of cervical root resorption. Non-surgical endodontic treatment was done for the maxillary left canine. The defect was surgically repaired using bioceramic putty. The 12-month recall revealed the good healing of the periodontal and periradicular conditions with no obvious clinical symptoms. At the 36-month recall visit, clinical and radiographic evidence of deterioration in the repair material was observed. At the 54-month follow-up, deterioration of repair material was observed with an increase in the extension of resorption in tooth 14 was detected. Reasons for this deterioration remain unclear. Ruling out all other factors for cervical root resorption, how rheumatoid arthritis contributes to cervical root resorption is still lacking/unclear. Dental care providers must be vigilant for signs of cervical root resorption in vulnerable patients with rheumatoid arthritis for early diagnosis and prompt treatment. Keywords: External root resorption, Inflammatory markers, Multiple root resorption, Rheumatoid arthritis, Resorption repair.

Primary failure of eruption and tooth resorption / Défaut primaire d'éruption et résorption radiculaire externe

Introduction: The number of adult patients who seek an orthodontic treatment is increasing. These Primary failure of eruption (PFE) is defined as the partial or complete failure of eruption of at least one posterior tooth, without any mechanical obstacle. A better understanding of the biological mechanisms involved in PFE would enable to refine the diagnostic and prognostic criteria. This rare disease is currently related to PTHR1 gene variants. This gene codes for a transmembrane receptor involved in bone metabolism. However, there is few evidence associating PFE and bone remodeling abnormalities such as external root resorption. External root resorption is the loss of cementum and dentin tissues, resulting from the activation of clastic cells. Materials and Methods: Human teeth affected by PFE were extracted and histological sections were made after fixation of the tissues in 4% PFA. The observations were correlated with three-dimensional imaging by cone beam computed tomography (CBCT) carried out in the preoperative phase. Results: Histological and radiographic analysis confirm the presence of ankylosis area in patients with no history of orthodontic treatment. Large areas of resorption of external root replacement were detected. Discussion: The results call the causal link between the appearance of ankylosis areas and the establishment of orthodontic traction in patients with PFE into question. The installation of an orthodontic force in this context could be only an aggravating factor, accelerating the processes of ankylosis or triggering them more prematurely. Conclusion: With or without orthodontic treatment, teeth with PFE are likely to progress to ankylosis and resorption of replacement external root.

Introduction: Les défauts primaires d'éruption (DPE) se caractérisent par l'échec total ou partiel de l'éruption d'une ou plusieurs dents postérieures, sans obstacle mécanique. Une meilleure compréhension des mécanismes biologiques impliqués dans les DPE permettrait d'affiner les critères diagnostiques et pronostiques. Cette pathologie rare est actuellement imputée à des variants du gène PTHR1. Ce gène code pour un récepteur transmembranaire impliqué dans le métabolisme osseux. Cependant, on trouve peu de données associant DPE et anomalies du remodelage osseux de type résorption radiculaire externe. La résorption radiculaire externe correspond à la perte de tissus cémentaire et dentinaire résultant de l'activation de cellules clastiques. Matériels et méthodes: Des dents d'origine humaine atteintes de DPE ont été avulsées et des coupes histologiques réalisées après fixation des tissus. Les observations ont été corrélées avec l'imagerie tridimensionnelle par tomographie volumique à faisceau conique (TVFC ou encore CBCT). Résultats: Les analyses histologiques et radiographiques montrent la présence de plage d'ankylose chez des patients sans antécédent de prise en charge orthodontique. De larges zones de résorptions radiculaires externes de remplacement ont été détectées. Discussion: Les résultats remettent en cause le lien de causalité entre l'apparition d'ankylose et la mise en place de traction orthodontique chez les patients atteints de DPE. La mise en place d'une force orthodontique dans ce contexte pourrait n'être qu'un facteur aggravant, accélérant les processus d'ankylose ou les déclenchant plus prématurément. Conclusion: Avec ou sans traitement orthodontique, les dents atteintes de DPE sont susceptibles d'évoluer vers l'ankylose et la résorption radiculaire externe de remplacement.

Cytotoxicity, genotoxicity, and immunohistochemical expression of p53 in the oral mucosal epithelium of adults following cone-beam computed tomography.

This study sought to assess the cytotoxicity, genotoxicity, and immunohistochemical (IHC) expression of p53 in the oral mucosal epithelium of adults following cone-beam computed tomography (CBCT). This before-and-after observational study evaluated 30 patients (15 males and 15 females); mean age 35 years, who required CBCT. Exfoliating epithelial cells of the buccal mucosa were collected with a cotton swab immediately before and 10 days after CBCT. Following Papanicolaou staining, genotoxicity was evaluated by the micronucleus assay. The frequencies of pyknosis, karyorrhexis, karyolysis, budding and binucleation as cytotoxicity factors were also recorded. Expression of p53 was evaluated by IHC staining. Data were analyzed by paired samples t-test. Micronucleated cells, pyknosis, karyorrhexis, karyolysis, budding, cytotoxicity, and expression of p53 increased significantly after CBCT. CBCT exerts genotoxic and cytotoxic effects and leads to overexpression of p53 protein in the oral buccal mucosal cells.

[Cone-beam CT analysis of external root resorption of maxillary incisors before and after traction of impacted canines].

Objective: To analyze the external root resorption of incisors caused by maxillary canine impaction, and to explore the changes of incisor external root resorption after orthodontic treatment. Methods: Twenty-four patients with impacted maxillary canines leading to external root resorption of incisors treated in Department of Orthodontics, Affiliated Hospital of Stomatology, Nanjing Medical University from July 2011 to January 2019 were selected. The age ranged from 10 to 14 years [(12.3±1.6) years], including 11 males and 14 females. The maxillary incisors with external root resorption before treatment were included in the resorption group (21 central incisors and 22 lateral incisors), and the maxillary incisors without external root resorption were used as the control group (26 central incisors and 21 lateral incisors). Cone-beam CT was taken before treatment, immediately after treatment and one year after treatment. At the one year follow-up 15 patients were collected (10 central incisors and 12 lateral incisors in the resorption group, while 16 central incisors and 12 lateral incisors in the control group). The root length and tooth volume of maxillary incisors were measured and analyzed before canine traction, after canine traction finished and at the one year follow-up. Results: After the treatment of maxillary impacted canines, the root length and volume of the central and lateral incisors in both resorption group and control group were significantly less than that before treatment (P<0.05). At the one year follow-up, the root length and volume of the incisors (central incisors in the resorption group and the central and lateral incisors in control group) were significantly less than those immediately after impacted canine traction (P<0.05). During the canine traction, the difference of the volume change in lateral incisors between the resorption group [(17±6) mm3] and the control group [(12±5) mm3] was statistically significant (t=2.51, P<0.05). During the one year follow-up period, the difference between the changes of the root length in maxillary central incisors in the resorption group [(0.5±0.4) mm] and in the control group [(0.2±0.1) mm] was statistically significant (t=2.35, P<0.05). Conclusions: For maxillary incisors with external root resorption caused by impacted maxillary canines, the external root resorption could not stop immediately after the treatment of impacted canines. The root resorption in maxillary lateral incisors mainly occured during the traction process, while the root resorption in maxillary central incisors existed during the orthodontic treatment and in the follow-up period.

Quantitative volumetric computed tomography embolic analysis, the Qanadli score, biomarkers, and clinical prognosis in patients with acute pulmonary embolism.

Detailed descriptions of acute pulmonary emboli (PE) morphology, total embolic volume (TEV), and their effects upon patients' clinical presentation and prognosis remain largely unexplored. We studied 201 subjects with acute PE to the emergency department of a single medical center from April 2009 to December 2014. Patient hemodynamics, Troponin I and D-dimer levels, echocardiography, and the 30-day, 90-day and long-term mortality were obtained. Contrast-enhanced computed tomography (CT) of pulmonary structures and 3-dimensional measures of embolic burden were performed. The results showed a linear association between the greater TEV and each of the following 4 variables (increasing incidence of right ventricular (RV) dysfunction, higher systolic pulmonary artery pressure (sPAP), greater RV diameter, and RV/left ventricular (LV) ratio (all p < 0.001)). Among the measures of CT and echocardiography, TEV and RV/LV ratio were significantly associated with impending shock. In backward stepwise logistic regression, TEV, age and respiratory rate remained independent associated with impending shock (OR: 1.58, 1.03, 1.18, respectively and all p < 0.005).Total embolic burden assessed by CT-based quantification serves as a useful index for stressed cardiopulmonary circulation condition and can provide insights into RV dysfunction and the prediction of impending shock.

Can Weightbearing Cone-beam CT Reliably Differentiate Between Stable and Unstable Syndesmotic Ankle Injuries? A Systematic Review and Meta-analysis.

BACKGROUND: Ankle injuries are common presentations to the emergency department and may lead to syndesmotic instability. These have a high socioeconomic burden due to prolonged rehabilitation, chronic pain, and posttraumatic arthritis. Early diagnosis is essential to minimize these complications, and the assessment of instability in the clinical setting is often limited by pain and clinician experience. Cross-sectional imaging of the distal syndesmosis accurately evaluates the syndesmosis through abnormal bony relationships, which in the presence of instability, worsens during physiological loading. Cone-beam CT (CBCT) has gained popularity in the diagnosis of these injuries because it enables syndesmotic assessment under weightbearing conditions, it mitigates the high radiation dose, and it is time-efficient. QUESTIONS/PURPOSES: The purposes of this systematic review were: (1) to establish normal values for weightbearing CBCT of the syndesmosis in uninjured ankles and ascertain interobserver reliability and (2) to identify the impact of weightbearing on the syndesmosis in patients with occult ankle injuries and assess the effect of patient demographics on these metrics. METHODS: This systematic review was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and registered in PROSPERO (ID CRD42021248623). MEDLINE, PubMed, Embase, and Emcare databases were searched for studies assessing for syndesmotic instability, of which 307 studies were screened and 11 studies with 559 ankles in 408 uninjured patients and 151 patients with syndesmotic instability were included. All patients 18 years of age or older presenting with unilateral ankle injuries who underwent weightbearing CBCT for the diagnosis of an occult fracture or syndesmotic instability compared with the uninjured contralateral side were included. A control group of uninjured ankles was identified during weightbearing CBCT performed for other indications such as forefoot or midfoot injuries. Methodological assessment of the studies was performed using the Risk of Bias In Non-randomized Studies (ROBINS-1) tool and most included studies had a low risk of bias. Thus, a random-effects restricted maximum likelihood ratio model was used. RESULTS: In the uninjured ankle, the mean area of the tibiofibular syndesmosis was 112.5 ± 7.1 mm 2 , which increased to 157.5 ± 9.6 mm 2 after injury when compared with uninjured ankles with a standardized mean difference of 29.5 (95% confidence interval 19.5 to 39.5; p < 0.01), and an excellent interobserver agreement (κ = 1.0 [95% CI 0.9 to 1.0]). However, syndesmosis volume decreased with age (ß = -0.76; p = 0.04), and therefore, has a negative association with increasing age. CONCLUSION: Our study has shown that the syndesmotic area is the most reliable parameter in the assessment of syndesmotic injuries because it increases in the presence of instability during weightbearing status. It is a composite measurement that could potentially allow clinicians to use weightbearing CBCT as an adjunct when there is a clinical suspicion of syndesmotic instability. Thus, weightbearing CBCT has the potential of being diagnostic of syndesmotic instability and should be evaluated against current radiological modalities to evaluate its accuracy. LEVEL OF EVIDENCE: Level IV, prognostic study.

Etiology of Tinnitus on CT and CBCT: A Narrative Review.

Tinnitus is commonly depicted as a ringing within the ears, but it can sound like roaring, clicking, hissing, or buzzing. It is a symptom that shows something is wrong in the auditory system, which includes the sound-related nerve that interfaces the inward ear to the brain, and the parts of the brain that handle sound. Generally, the causes of tinnitus include: Otologic causes, Neurologic causes, temporomandibular joint, and masticatory muscle disorders. Causes of tinnitus can be diagnosed with CT and CBCT. A CT scan or computed tomography scan is a medical imaging technique used in radiology that can obtain detailed internal images of the brain and CBCT is a developing imaging technique designed to provide relatively low-dose high-spatial-resolution visualization of highcontrast structures in the head and neck and other anatomic areas. CBCT has a lower radiation dose, shorter imaging time, and better resolution than CT. This chapter reviews etiology of tinnitus on CT and CBCT.

Evaluation of IGRT-Induced Imaging Doses and Secondary Cancer Risk for SBRT Early Lung Cancer Patients In Silico Study.

OBJECTIVES: This study performed dosimetry studies and secondary cancer risk assessments on using electronic portal imaging device (EPID) and cone beam computed tomography (CBCT) as image guided tools for the early lung cancer patients treated with SBRT. METHODS: The imaging doses from MV-EPID and kV-CBCT of the Edge accelerator were retrospectively added to sixty-one SBRT treatment plans of early lung cancer patients. The MV-EPID imaging dose (6MV Photon beam) was calculated in Pinnacle TPS, and the kV-CBCT imaging dose was simulated and calculated by modeling of the kV energy beam in TPS using Pinnacle automatic modeling program. Three types of plans, namely PlanEPID, PlanCBCT and Planorigin, were generated with incorporating doses of EPID, CBCT and no imaging, respectively, for analysis. The effects of imaging doses on dose-volume-histogram (DVH) and plan quality were analyzed, and the excess absolute risk (EAR) of secondary cancer for ipsilateral lung was evaluated. RESULTS: The regions that received less than 50 cGy were significantly impacted by the imaging doses, while the isodose lines greater than 1000 cGy were barely changed. The DVH values of ipsilateral lung increased the most in PlanEPID, followed by PlanCBCT. Compared to Planorigin on the average, the estimated EAR of ipsilateral lung in PlanEPID increased by 3.43%, while the corresponding EAR increase in PlanCBCT was much smaller (about 0.4%). Considering only the contribution of the imaging dose, the EAR values for the ipsilateral lung due to the MV-EPID dose in 5 years,10 years and 15 years were 1.49 cases, 2.09 cases and 2.88 cases per 104PY respectively, and those due to the kV-CBCT dose were about 9 times lower, correspondingly. CONCLUSIONS: The imaging doses produced by MV-EPID and kV-CBCT had little effects on the target dose coverage. The secondary cancer risk caused by MV-EPID dose is more than 8.5 times that of kV-CBCT.

Improving Cone-Beam CT Angiography for Prostatic Artery Embolization: Is a Low-Dose Protocol Equivalent to the Standard?

PURPOSE: To compare the utility of low-dose versus standard cone-beam computed tomography (CT) angiography protocols in identifying nontarget embolization (NTE) during prostatic artery embolization (PAE). MATERIALS AND METHODS: A prospective, single-center, Phase-1 study (NCT02592473) was conducted for lower urinary tract symptoms in benign prostatic hyperplasia. Prostate volume, international prostate symptom score (IPSS), quality of life score (QoL), International Index of Erectile Function (IIEF), peak flow rate, UCLA Prostate Cancer Index (UCLA-PCI), and postvoid residual were recorded at baseline and 1, 3, 6, 12, and 24-months after PAE. Six-second (standard protocol, n = 29) or 5-second (low-dose protocol n = 45) rotations were made. Images were selected and matched in pairs by areas of NTE and compared by readers using a binomial generalized estimating equation model. Procedural outcomes were analyzed using a linear mixed model. RESULTS: Seventy-four cone-beam CT angiographies were performed in 21 patients. IPSS and QoL scores significantly improved (P <.05). There was no change in UCLA-PCI or IIEF scores. Dose area product of the low- and standard-dose protocol were 37,340.82 mGy·cm2 ± 104.66 and 62,645.66 mGy·cm2 ± 12,711.48, respectively, representing a dose reduction of 40.4%. A total of 120 comparisons showed no preference between the 2 protocols (P =.24). Observers identified 76 and 69 instances of NTE in the standard- and low-dose protocols, respectively (P =.125). CONCLUSIONS: Low-dose cone-beam CT angiography achieved equivalent clinical utility in identifying NTE during PAE, with the advantage of a lower radiation dose.

Clinical Outcomes of a Randomized Trial of Adaptive Plan-of-the-Day Treatment in Patients Receiving Ultra-hypofractionated Weekly Radiation Therapy for Bladder Cancer.

PURPOSE: Hypofractionated radiation therapy can be used to treat patients with muscle-invasive bladder cancer unable to have radical therapy. Toxicity is a key concern, but adaptive plan-of the day (POD) image-guided radiation therapy delivery could improve outcomes by minimizing the volume of normal tissue irradiated. The HYBRID trial assessed the multicenter implementation, safety, and efficacy of this strategy. METHODS: HYBRID is a Phase II randomized trial that was conducted at 14 UK hospitals. Patients with T2-T4aN0M0 muscle-invasive bladder cancer unsuitable for radical therapy received 36 Gy in 6 weekly fractions, randomized (1:1) to standard planning (SP) or adaptive planning (AP) using a minimization algorithm. For AP, a pretreatment cone beam computed tomography (CT) was used to select the POD from 3 plans (small, medium, and large). Follow-up included standard cystoscopic, radiologic, and clinical assessments. The primary endpoint was nongenitourinary Common Terminology Criteria for Adverse Events (CTCAE) grade ≥ 3 (≥G3) toxicity within 3 months of radiation therapy. A noncomparative single stage design aimed to exclude ≥30% toxicity rate in each planning group in patients who received ≥1 fraction of radiation therapy. Local control at 3-months (both groups combined) was a key secondary endpoint. RESULTS: Between April 15, 2014, and August 10, 2016, 65 patients were enrolled (SP, n = 32; AP, n = 33). The median follow-up time was 38.8 months (interquartile range [IQR], 36.8-51.3). The median age was 85 years (IQR, 81-89); 68% of participants (44 of 65) were male; and 98% of participants had grade 3 urothelial cancer. In 63 evaluable participants, CTCAE ≥G3 nongenitourinary toxicity rates were 6% (2 of 33; 95% confidence interval [CI], 0.7%-20.2%) for the AP group and 13% (4 of 30; 95% CI, 3.8%-30.7%) for the SP group. Disease was present in 9/48 participants assessed at 3 months, giving a local control rate of 81.3% (95% CI, 67.4%-91.1%). CONCLUSIONS: POD adaptive radiation therapy was successfully implemented across multiple centers. Weekly ultrahypofractionated 36 Gy/6 fraction radiation therapy is safe and provides good local control rates in this older patient population.

Radiation Dose during Transarterial Radioembolization: A Dosimetric Comparison of Cone-Beam CT and Angio-CT Technologies.

PURPOSE: To evaluate the radiation dose differences for intraprocedural computed tomography (CT) imaging between cone-beam CT and angio-CT acquired during transarterial radioembolization (TARE) therapies for hepatocellular carcinoma. MATERIALS AND METHODS: A retrospective cohort of 22 patients who underwent 23 TARE procedures were selected. Patients were imaged in both cone-beam CT and angio-CT rooms as a part of their conventional treatment plan. Effective dose contributions from individual CT acquisitions as well as the cumulative dose contributions from procedural 3D imaging were evaluated. Angiography dose contributions were omitted. Cone-beam CT images were acquired on a C-arm Philips Allura system. Effective doses were evaluated by coupling previously published conversion factors (effective dose per dose-area product) to patient's dose-area product meter readings after the procedure. Angio-CT images were acquired on a hybrid Canon Infinix-i Aquilion PRIME system. Effective doses from angio-CT scans were estimated using Radimetrics. Comparisons of a single patient's dose differential between the 2 technologies were made. RESULTS: The mean effective dose from a single CT scan was 6.42 mSv and 5.99 mSv in the cone-beam CT room and the angio-CT room, respectively (P = .3224), despite the greater field of view and average craniocaudal scan coverage in angio-CT. The mean effective dose summed across all CTs in a procedure was 12.89 mSv and 34.35 mSv in the cone-beam CT room and the angio-CT room, respectively (P = .0018). CONCLUSIONS: The mean effective dose per CT scan is comparable between cone-beam CT and angio-CT when considered in direct comparison for a single patient.

Moderately hypofractionated radiotherapy for localized prostate cancer: updated long-term outcome and toxicity analysis.

PURPOSE: Evaluation of long-term outcome and toxicity of moderately hypofractionated radiotherapy using intensity-modulated radiotherapy (IMRT) with simultaneous integrated boost treatment planning and cone beam CT-based image guidance for localized prostate cancer. METHODS: Between 2005 and 2015, 346 consecutive patients with localized prostate cancer received primary radiotherapy using cone beam CT-based image-guided intensity-modulated radiotherapy (IG-IMRT) and volumetric modulated arc therapy (IG-VMAT) with a simultaneous integrated boost (SIB). Total doses of 73.9 Gy (n = 44) and 76.2 Gy (n = 302) to the high-dose PTV were delivered in 32 and 33 fractions, respectively. The low-dose PTV received a dose (D95) of 60.06 Gy in single doses of 1.82 Gy. The pelvic lymph nodes were treated in 91 high-risk patients to 45.5 Gy (D95). RESULTS: Median follow-up was 61.8 months. The 5­year biochemical relapse-free survival (bRFS) was 85.4% for all patients and 93.3, 87.4, and 79.4% for low-, intermediate-, and high-risk disease, respectively. The 5­year prostate cancer-specific survival (PSS) was 94.8% for all patients and 98.7, 98.9, 89.3% for low-, intermediate-, and high-risk disease, respectively. The 5­year and 10-year overall survival rates were 83.8 and 66.3% and the 5­year and 10-year freedom from distant metastasis rates were 92.2 and 88.0%, respectively. Cumulative 5­year late GU toxicity and late GI toxicity grade ≥2 was observed in 26.3 and 12.1% of the patients, respectively. Cumulative 5­year late grade 3 GU/GI toxicity occurred in 4.0/1.2%. CONCLUSION: Moderately hypofractionated radiotherapy using SIB treatment planning and cone beam CT image guidance resulted in high biochemical control and survival with low rates of late toxicity.

What Is the Diagnostic Accuracy of Flat-panel Cone-beam CT Arthrography for Diagnosis of Scapholunate Ligament Tears?

BACKGROUND: Cone beam CT (CBCT) is a widely available technique with possible indications in carpal ligament injuries. The accuracy of CBCT arthrography in diagnosing traumatic tears of the scapholunate ligament has not been reported. QUESTIONS/PURPOSES: (1) What is the diagnostic accuracy of CBCT and how does it relate to the accuracy of multislice CT arthrography and conventional arthrography in diagnosing scapholunate ligament tears? (2) What is the estimated magnitude of skin radiation doses of each method? METHODS: This secondary analysis of a previous prospective study included 71 men and women with suspected scapholunate ligament tears and indications for arthroscopy. Preoperative imaging was conventional arthrography and either MSCT arthrography for the first half of patients to be included (n = 36) or flat-panel CBCT arthrography for the remaining patients (n = 35). Index tests identified therapy-relevant SLL tears with dorsal or complete SLL ruptures, and these tears were compared with relevant SLL tears which were determined through arthroscopy as Geissler Stadium III and IV by probing the instable SL joint with a microhook or arthroscope. These injuries were treated by open ligament repair and Kirschner wire fixation. Accuracy values and 95% confidence intervals were calculated. Additional estimates of the radiation skin doses of each CBCT exam and two MSCT protocols were subsequently calculated using dose area products, dose length products, and CT dose indices. RESULTS: The diagnostic accuracy was high for all imaging methods. 95% CIs were broadly overlapping and therefore did not indicate differences between the diagnostic groups: Sensitivity of CBCT arthrography was 100% (95% CI 77 to 100), specificity was 95% (95% CI 76 to 99.9), positive predictive value was 93% (95% CI 68 to 99.8), and negative predictive value was 100% (95% CI 83 to 100). For MSCT arthrography, the sensitivity was 92% (95% CI 64 to 99.8), specificity was 96% (95% CI 78 to 99.9), positive predictive value was 92% (95% CI 64 to 99.8), and negative predictive value was 96% (95% CI 78 to 99.9). For conventional arthrography, the sensitivity was comparably high: 96% (95% CI 81 to 99.9). Specificity was (81% [95% CI 67 to 92]); the positive predictive value was 77% (95% CI 59 to 89) and negative predictive value was 97% (95% CI 86 to 99.9). Estimated mean (range) radiation skin doses were reported in a descriptive fashion and were 12.9 mSv (4.5 to 24.9) for conventional arthrography, and 3.2 mSv (2.0 to 4.8) for CBCT arthrography. Estimated radiation skin doses were 0.2 mSv and 12 mSv for MSCT arthrography, depending on the protocol. CONCLUSION: Flat-panel CBCT arthrography can be recommended as an accurate technique to diagnose scapholunate ligament injuries after wrist trauma. Estimated skin doses are low for CBCT arthrography and adapted MSCT arthrography protocols. LEVEL OF EVIDENCE: Level III, diagnostic study.

Assessment of Eye Lens Dose Reduction When Using Lateral Lead Shields on the Patient's Head during Neurointerventional Fluoroscopic Procedures and Cone-beam Computed Tomography (CBCT) Scans.

The purpose of this study was to evaluate the effect of placing small lead shields on the temple region of the skull to reduce radiation dose to the lens of the eye during interventional fluoroscopically-guided procedures and cone-beam computed tomography (CBCT) scans of the head. EGSnrc Monte-Carlo code was used to determine the eye lens dose reduction when using lateral lead shields for single x-ray projections, CBCT scans with different protocols, and interventional neuroradiology procedures with the Zubal computational head phantom. A clinical C-Arm system was used to take radiographic projections and CBCT scans of anthropomorphic head phantoms without and with lead patches, and the images were compared to assess the effect of the shields. For single lateral projections, a 0.1 (0.3)-mm-thick lead patch reduced the dose to the left-eye lens by 40% to 60% (55% to 80%) from 45° to 90° RAO and to the right-eye lens by around 30% (55%) from 70° to 90° RAO. For different CBCT protocols, the reduction of lens dose with a 0.3-mm-thick lead patch ranged from 20% to 53% at 110 kVp. For CBCT scans of the anthropomorphic phantom, the lead patch introduced streak artifacts that were mainly in the orbital regions but were insignificant in the brain region where most neurointerventional activity occurs. The dose to the patient's eye lens can be reduced considerably by placing small lead shields over the temple region of the head without substantially compromising image quality in neuro-imaging procedures.