Diagnostic yield of CT-guided lung biopsies: how can we limit negative sampling?

Objectives:To investigate whether lesion imaging features may condition the outcome of CT-guided lung biopsy (CTLB) and to develop a scoring system of biopsy outcome prediction.Methods:This is a single center retrospective study on 319 CTLBs that were performed in 319 patients (167 males/152 females, mean age 68 ± 12.2). Uni- and multivariate analysis were performed aiming to assess the imaging features that are likely to be correlated to a negative biopsy outcome and patients were stratified in groups accordingly.Results:Technical success was 100%. 78% of the biopsies (250/319) led to a concrete histology report (218 malignant/32 benign). The remaining lesions led to concrete histology at a second attempt that occurred on a later time. Multivariate analysis revealed increased risk of inconclusive result for nodules with low fludeoxyglucose uptake [odds ration (OR) = 2.64, 95% confidence interval (CI) 1.4–4.97; p = 0.003], for nodules with diameter smaller than 18 mm (OR = 2.03, 95% CI 1.14–3.62; p = 0.017) and for nodules that are located in one of the lung bases (OR = 1.96, 95% CI 1.06–3.62; p = 0.033). Three different groups of patients were identified accordingly with low (<30%), medium (30–50%) and high (>50%) probability of obtaining an inconclusive biopsy sample.Conclusion:This study confirms that percutaneous CT-guided biopsy in nodules that are either small in diameter or present low positron emission tomography-fludeoxyglucose uptake or are in one of the lung bases may lead to inconclusive histology. This information should be factored when planning percutaneous biopsies of such nodules in terms of patient informed consent and biopsy strategy.Advances in knowledge:Inconclusive histology after lung biopsy may be subject to factors irrelevant to technical success. Lung biopsy histology outcomes may be predicted and avoided after adequate planning.     

Diagnostic accuracy and complication rates of percutaneous CT-guided coaxial needle biopsy of pulmonary lesions

PURPOSEThe aim of this retrospective study was to evaluate and compare diagnostic accuracy and complication rates of percutaneous computed tomography (CT)-guided biopsies of pulmonary lesions 10–35 mm, 35–50 mm, and >50 mm, using the coaxial biopsy technique.METHODSOver a 4-year period, 235 lung biopsies were performed using the coaxial biopsy technique with 18G semi-automated true-cut needle. There were 163 (69.4%) male and 72 (30.6%) female patients, with a mean age of 64.01±9.18 years (18–85 years). The mean lesion size was 59.6±29.3 mm. The lesions were stratified into three groups according to size: lesions <35 mm (n=42, 17.9%), lesions 35–50 mm (n=53, 22.5%), and lesions >50 mm (n=140, 59.6%). Diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated for all biopsies, and for each group separately, as well as the incidence of complications.RESULTSThe overall diagnostic accuracy was 95.4%, with 95.52% sensitivity, 100% specificity, 100% PPV, and 47.37% NPV. For lesions <35 mm, diagnostic accuracy, sensitivity, and PPV were 100%. The lowest diagnostic accuracy was 93.9% in lesions >50 mm, with 93.65% sensitivity, 100% specificity, 100% PPV, and 42.86% NPV. An adequate sample was obtained in 219 core biopsies (93.2%), while 16 biopsies (6.8%) were nondiagnostic due to necrosis (4.25%) and insufficient biopsy material (2.55%). The most frequent complication was minor pneumothorax, which was seen at a rate of 19.1%; pneumothorax requiring chest tube placement occurred in 3 patients (1.3%).CONCLUSIONDiagnostic accuracy decreased with increasing lesion size. On the other hand, complication rates were higher in smaller lesions, more distanced from the pleura.

Computed tomography (CT)-guided percutaneous needle biopsy is a well-established method in the diagnostic algorithm of various pulmonary lesions, with two types of biopsy techniques employed, fine-needle aspiration biopsy (FNAB) and core biopsy (CB). Both techniques yield high diagnostic accuracy for carcinomas, from 89% in FNAB to 98% in CB (1). Coaxial biopsy technique has a reported overall diagnostic accuracy for both malignant and benign lesions ranging from 82.6% to 95% (2–4).Besides the needle type, other factors such as lesion size, nature of the lesion, experience and skills of interventional radiologist influence the diagnostic accuracy. Lesion size ≥1 cm is reported as a significant risk factor decreasing diagnostic accuracy, but in published data lesions >5 cm and even ≥3.1 cm, are also identified as factors that decrease the diagnostic accuracy mainly due to the higher rates of necrosis (4, 5).The most frequent complication in lung biopsy is pneumothorax, with the reported pooled rate 25.3% for CB and 18.8% for FNAB (6).The aim of this retrospective single-center study was to determine diagnostic accuracy and complication rates of percutaneous CT-guided coaxial lung biopsies of pulmonary lesions stratified by lesion size into <35 mm, 30–50 mm, and >50 mm lesions, as well as to identify the relevant risk factors.     

Factors influencing the total procedure time of CT-guided percutaneous core-needle biopsies of lung nodules: a retrospective analysis

PURPOSEThis study aims to investigate the factors that influence total procedure time when performing computed tomography (CT)-guided percutaneous core-needle lung biopsies.METHODSThis is a cross-sectional study of 673 patients, who underwent a CT-guided percutaneous core-needle biopsy at a tertiary care center from March 2014 to August 2016. Data on patient, nodule, and procedural factors and outcomes were collected retrospectively. Univariate linear regression and a multivariate stepwise linear regression were utilized for analysis.RESULTSFactors most strongly associated with prolonged procedure duration include 20-gauge needle use when compared with 18-gauge needle use (estimated difference in time = 1.19), collecting additional core biopsies (estimated difference in time = 1.10), decubitus nodule side up (DNSU; estimated difference in time = 1.42), and supine positioning (estimated difference in time = 1.16) relative to decubitus nodule side down positioning, and increased nodule distance from the skin surface (estimated difference in time = 1.03). Increased nodule length (estimated difference in time = 0.93) was associated with reductions in procedure duration. Prolonged procedure time was associated with an increased rate of pneumothorax (odds ratio (OR) = 1.02; P < .0001) and decreased rate of pulmonary hemorrhage (OR = 0.97; P < .0001).CONCLUSIONThe use of 20-gauge biopsy needle, collecting additional core biopsies, DNSU and supine positioning, smaller nodule size, and increasing nodule distance from the skin surface were associated with increased procedure time for CT-guided core needle biopsies of lung nodules. Prolonged procedure time is associated with a higher rate of pneumothorax and a lower rate of pulmonary hemorrhage.

Main points

• Various procedural, lung nodule, and patient-related variables were found to have an association with total duration for the completion of computed tomography (CT)-guided core needle lung biopsies.
• Positioning patients in the decubitus nodule side down orientation and decreasing the total distance between the lung nodule and skin surface were most strongly associated with reductions in total procedure duration.
• The utilization of 20-gauge needles most strongly prolonged procedure duration, and the use of 18-gauge needles should be considered for efficiency and larger yield of tissue for biopsy.
• Additional factors associated with shorter procedure times include lower patient body mass index, chronic obstructive pulmonary disorder, involvement of a resident or fellow, larger nodules, and acquiring fewer biopsy samples.
• Longer biopsy time was associated with a higher odds of pneumothorax although further studies are required to determine causality.

Computed tomography (CT)-guided biopsy is the preferred technique for obtaining lung tissue through the use of aspiration and/or cutting needles.¹ The primary use of CT-guided percutaneous core biopsies of the lung is to collect and analyze tissue for malignant potential or establish the pathological foundation for the abnormal lung tissue. The reported ranges of sensitivity, specificity, and accuracy of core-needle lung tissue biopsies establishing benign or malignant characteristics of collected tissue are 85.7%-97.4%, 88.6%-100.0%, and 89.0%-96.9% respectively.² Moreover, CT-guided core lung biopsies provide tissue samples essential for identifying the presence of specific oncogenic driver mutations, such as epidermal growth factor receptor, anaplastic lymphoma kinase, and programmed death-ligand 1, necessary for targeted immunotherapy of malignant tumors.³An understanding of the various patient, nodule, and procedural factors that influence the duration of these procedures will enable physicians to provide better patient care and help inform patients before undergoing a CT-guided core lung biopsy. Moreover, models predicting procedure length could be valuable to optimize scheduling for interventional radiology departments. However, the current literature investigating factors that influence CT-guided lung biopsies procedure times is minimal and needs further exploration. To our knowledge, there is no current literature investigating factors associated with procedure time. However, some studies have shown smaller lesions sizes to be associated with prolonged procedure time as these lesions encompass a smaller target area that demands more technical needle readjustments.^1,4,5 Unfortunately, these studies did not investigate procedure time with other factors, such as nodule location or smoking history, that may also influence procedure time.Likewise, there is no current literature to our knowledge that investigates the relationship between procedure duration and complications. The 2 most common complications following a CT-guided percutaneous lung biopsy are pneumothorax and pulmonary hemorrhage. The rate of pneumothorax following a CT-guided percutaneous lung biopsy ranges from 17% to 26.6%, with 1%-14.2% of these patients requiring chest tube placement to treat the pneumothorax.^1,6-10 Meanwhile, the reported incidence of pulmonary hemorrhage ranges from 4% to 27%.^1,6-10 Given the prevalence of these complications, identifying any association between procedure time and complications is also of importance.For the purposes of our study, we intend to determine the factors that influence the procedure time of a conventional CT-guided core lung biopsy. However, this study also aims to investigate other factors that may influence procedure time, such as patient age or body mass index (BMI), as well as any potential correlations between procedure duration and outcomes.     

Cone-Beam CT-Guided Percutaneous Transthoracic Needle Lung Biopsy of Juxtaphrenic Lesions: Diagnostic Accuracy and Complications

ObjectiveTo investigate the diagnostic accuracy and complications of cone-beam CT-guided percutaneous transthoracic needle biopsy (PTNB) of juxtaphrenic lesions and identify the risk factors for diagnostic failure and complications.Materials and MethodsIn total, 336 PTNB procedures for lung lesions (mean size ± standard deviation [SD], 4.3 ± 2.3 cm) abutting the diaphragm in 326 patients (189 male and 137 female; mean age ± SD, 65.2 ± 11.4 years) performed between January 2010 and December 2014 were included. The accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the PTNB procedures for the diagnosis of malignancy were measured based on the intention-to-diagnose principle. The risk factors for diagnostic failures and complications were evaluated using logistic regression analysis.ResultsThe accuracy, sensitivity, specificity, PPV, and NPV were 92.7% (293/316), 91.3% (219/240), 91.4% (74/81), 96.9% (219/226), and 77.9% (74/95), respectively. There were 23 diagnostic failures (7.3%), and lesion sizes ≤ 2 cm (p = 0.045) were the only significant risk factors for diagnostic failure. Complications occurred in 98 cases (29.2%), including 89 cases of pneumothorax (26.5%) and 7 cases of hemoptysis (2.1%). The multivariable analysis showed that old age (> 65 years) (p = 0.002), lesion size of ≤ 2 cm (p = 0.003), emphysema (p = 0.006), and distance from the pleura to the target lesion (> 2 cm) (p = 0.010) were significant risk factors for complications.ConclusionThe diagnostic accuracy of cone-beam CT-guided PTNB of juxtaphrenic lesions for malignancy was fairly high, and the target lesion size was the only significant predictor of diagnostic failure. Complications of cone-beam CT-guided PTNB of juxtaphrenic lesions occurred at a reasonable rate.     

CT-Guided Transthoracic Biopsy of Lung Lesions Using a Non-Coaxial Biopsy Needle Technique: CT Characteristics Predictive for Diagnostic Accuracy and Pneumothorax

Objectives:To analyze computed tomography (CT) characteristics predictive for diagnostic accuracy and pneumothorax in CT fluoroscopy-guided transthoracic biopsy (CTF-TTB) of lung lesions using non-coaxial biopsy needle technique.Methods:Retrospectively 274 lung lesion biopsies with confirmed histology were included in our study. CTF-TTB was done using an 18-gauge non-coaxial cutting needle. Diagnostic accuracy rates were calculated per lesion size and CT and procedural characteristics were evaluated for their predictive value regarding diagnostic accuracy and development of pneumothorax (maximal nodule diameter, distance to pleura, location per lung segment, nodule composition, benign versus malignant histology, and number of specimens).Results:Overall diagnostic accuracy of CTF-TTB was high (93%). Diagnostic accuracy for lesions ≤10 mm was 81%. Maximal nodule diameter was the only predictive CT characteristic for diagnostic success (p = 0.03). Pneumothorax occurred in 27%. Distance of lesion to pleura was the only risk factor for pneumothorax (p < 0.00001). Pneumothorax rates were significantly lower in subpleural lesions (14%) compared to those located 1–10 mm (47%), 10–20 mm (33%), and >20 mm from pleura (29%).Conclusions:High diagnostic accuracy rates were achieved with CTF-TTB using non-coaxial biopsy technique, even for lesions ≤10 mm. Pneumothorax rates were comparable with other studies. Lesion size was the only predictive CT characteristic for diagnostic accuracy. Distance to pleura was the only risk factor for pneumothorax.     

Does PSA level affect the choice of prostate puncture methods among MRI-ultrasound fusion targeted biopsy,transrectal ultrasound systematic biopsy or the combination of both?

Objectives:To explore whether prostate-specific antigen (PSA) affects the choice of prostate puncture methods by comparing MRI-ultrasound fusion targeted biopsy (MRI-TBx) with transrectal ultrasound systematic biopsy (TRUS-SBx) in the detection of prostate cancer (PCa), clinically significant prostate cancer (csPCa) and non-clinically significant prostate cancer (nsPCa) in different PSA groups (<10.0,10.0–20.0 and>20.0 ng ml⁻¹).Methods:A total of 190 patients with 215 lesions who underwent both MRI-TBx and TRUS-SBx were included in this retrospective study. PSA was measured pre-operatively and stratified to three levels. The detection rates of PCa, csPCa and nsPCa through different methods (MRI-TBx, TRUS-SBx, or MRI-TBx +TRUS SBx) were compared with stratification by PSA.Results:Among the 190 patients, the histopathological results revealed PCa in 126 cases, including 119 csPCa. In PSA <10.0 ng ml⁻¹ group, although the detection rates of PCa and csPCa by MRI-TBx were higher than those of TRUS-SBx, no significant differences were observed (p = 0.741; p = 0.400). In PSA 10.0–20.0 ng ml⁻¹ group, difference between the detection rate of csPCa with TRUS-SBx and the combined method was statistically significant (p = 0.044). As for PSA >20.0 ng ml⁻¹, MRI-TBx had a higher csPCa rate than TRUS-SBx with no statistical significance noted (p = 0.600).Conclusion:MRI-TBx combined with TRUS-SBx could be suitable as a standard detection approach for csPCa in patients with PSA 10.0–20.0 ng ml⁻¹. As for PSA >20.0 and <10.0 ng ml⁻¹, both MRI-TBx and TRUS-SBx might provide effective solutions for tumor detection.Advances in knowledge:This study gives an account of choosing appropriate prostate puncture methods through PSA level.     

CT-guided preoperative localization of ground glass nodule: comparison between the application of embolization microcoil and the locating needle designed for pulmonary nodules

Objectives:To compare the efficacy and safety of pre-operative localization of ground glass nodule (GGN) using embolization microcoils and the locating needles designed for pulmonary nodules.Methods:From June 2019 to December 2020, 429 patients who received CT-guided localization of single GGN before video-assisted thoracoscopic surgery (VATS) were enrolled. The diameter and depth of GGNs were 0.84 ± 0.39 cm and 1.66 ± 1.37 cm. Among 429 cases, the first 221 GGNs were marked with microcoils (the microcoil group), and the remaining 208 GGNs were marked with the locating needles designed for pulmonary nodules (the locating needle group). SPSS 17.0 statistical software was used to compare the marking success rate, marking time, marking-related complications between two groups. p values < 0.05 were considered statistically significant.Results:The marking time in the microcoil group was longer than that in the locating needle group (11.1 ± 3.9 vs 8.2 ± 2.0 min, t = −7.87, p = 0.000). The marking success rate in the microcoil group was lower than that in the locating needle group (91.4% vs 98.6%, χ² = 11.27, p = 0.001). In the microcoil group, marking failures included 16 cases of microcoil dislocation and 3 cases of unsatisfactory microcoil position, while all 3 cases of marking failure in the locating needle group were due to unsatisfactory anchor position. No significant differences in the incidence of total complications (23.1% vs 22.1%), pneumothorax (18.1% vs 19.2%), hemorrhage (9.5% vs 9.1%), and hemoptysis (1.8% vs 1.4%) were observed between the two groups. All the complications were minor and did not need special treatment. Except for one case in the microcoil group, which was converted to thoracotomy, the remaining 428 GGNs were successfully resected by VATS.Conclusions:It is safe and effective to perform pre-operative localization of GGN using either embolization microcoil or the locating needle designed for pulmonary nodules. The locating needle is superior to microcoil for marking GGN in terms of procedure time and the success rate. The complication rate of both methods is similar.Advances in knowledge:The locating needle designed for pulmonary nodules has recently been used to mark pulmonary nodule. Its structure can effectively avoid dislocation after localization, and the marking process is simple and quick. Compared with localization using microcoil, it takes less time and has higher success rate to mark GGNs using the locating needle. The complication rate of both methods is similar.     

Retrospective comparative study of efficacy,safety and outcome of percutaneous intervention for Budd-Chiari syndrome patients with bilirubin less than 3 and 3–6 mg/dl

Objective:Comparing the efficacy, safety and outcome of percutaneous intrervention for Budd-Chiari Syndrome (BCS) patients with bilirubin less than 3 and 3–6 mg dl⁻¹.Methods and materials:188 BCS patients having serum bilirubin ≤6 mg dl⁻¹ and underwent percutaneous interventions were divided into two groups based on bilirubin level: 151 patients having bilirubin <3 mg dl⁻¹ were included in Group 1; and 37 patients having bilirubin 3–6 mg dl⁻¹ were included in Group 2. Both group were compare for technical success (successful recanalization of hepatic venous stenosis or creation of portocaval shunt with post-procedure gradient ≤5 mm of Hg), Safety (procedure-related mortality/morbidity or patient required transplantation) and outcome (resolution of clinical symptoms and survival).Results:Technical success was 94.7% in Group 1–89.1% in Group 2 with overall success rate was 93.6%. No significant differences observed between the two groups in regards to procedure related complication. Overall transplant-free survival at 1 and 5 years after intervention in both groups was 96.3 and 91.2% respectively. 1-year and 5-year survivals in Group 1 was 96.7%, and 93.1%, whereas Group 2 was 94.6 and 90.1% with no statically significantly difference between the two groups (p = 0.59). Percutaneous intervention results are good in patients having bilirubin up to 6 mg dl⁻¹, i.e. mild to moderate liver dysfunctions.Conclusion:Technical success, survival and outcome of percutaneous intervention in BCS patients having serum bilirubin 3–6 mg dl⁻¹ was comparable to patients having bilirubin level <3 mg dl⁻¹.Advances in knowledge:Percutaneous intervention treatment is suitable for treatment for symptomatic BCS patients having bilirubin up to 6 mg  dl⁻¹.     

Is it possible to estimate volume of bone defects formed on dry sheep mandibles more practically by secondarily reconstructing section thickness of cone beam computed tomography images?

Objectives:The purpose of this study was to evaluate the effect of section thickness on volume estimations of bone defects scanned using cone beam computed tomography (CBCT).Methods:25 bone defects were prepared on sheep mandibles and scanned using a KaVo 3D eXam (KaVo Dental, Biberach, Germany) CBCT device. Section thickness of images were reconstructed at 0.25, 0.5, and 0.75 mm to estimate the volume of these defects using the semiautomatic segmentation method. The volume averages obtained using microcomputed tomography and Archimedes’ method served as reference values. The estimated volumes at each section thickness were compared with the actual volumes using the Friedman test. The accuracy of volume estimation was determined by the percentage error with respect to the reference values, and the mean absolute error (MAE) was calculated.Results:Volumetric values of bone defects obtained with CBCT at section thicknesses up to 0.5 mm were compatible with the actual volumes (p > 0.05). The percentage errors at section thicknesses of 0.25, 0.5, and 0.75 mm were −5.4%, −7.3%, and −13.1%, respectively. The mean absolute errors were 13.6 mm³, 15.7 mm³, and 18.2 mm³, respectively.Conclusions:The section thickness values of CBCT images can be increased to a reasonable level to obtain accurate volume estimation results and save time. The semiautomatic segmentation method can be used reliably for volume estimations of bone defects.     

CT-guided transthoracic needle biopsy of pulmonary lesions: comparison between the cutting needle and aspiration needle

Objectives:To compare CT-guided transthoracic cutting needle biopsy (TCNB) with transthoracic aspiration needle biopsy (TANB) for pulmonary lesions with respect to the diagnostic accuracy and complication rate.Methods:Of the 859 cases that underwent consecutive CT-guided biopsy of pulmonary lesions, 713 cases confirmed by surgical pathology or clinical follow-up were enrolled. Of these, the first consecutive 275 cases underwent TANB, and the remaining 438 received TCNB. The final diagnosis determined the accuracy of biopsy. Based on the post-biopsy CT and clinical medical records, the presence or absence of biopsy-related complications was determined. The χ² test was used to compare the differences between TCNB and TANB in terms of diagnostic accuracy and complication rate.Results:Among the 713 biopsy lesions, the final diagnosis was malignant in 411 cases and benign in 302 cases. As compared to TANB, the diagnostic accuracy of TCNB (98.9% vs 93.8%, χ² = 14.35, p < 0.01), sensitivity to malignant lesions (97.8% vs 90.6%, χ² = 10.58, p < 0.01), negative predictive value (97.6% vs 84.8%, χ² = 19.03, p < 0.01), and specific diagnostic rate for benign lesions (73.4% vs 57.9%, χ² = 7.29, p < 0.01) were improved. On the other hand, a statistical difference was detected between TCNB and TANB with respect to the incidence of pneumothorax (20.6% vs 13.1%, χ² = 6.46, p = 0.01), hemorrhage (32.2% vs 13.1%, χ² = 33.03, p < 0.01), and hemoptysis (8.2% vs 3.3%, χ² = 6.87, p < 0.01). One patient died just several minutes after TCNB due to severe hemorrhage with hemoptysis.Conclusions:Compared to TANB, CT-guided TCNB improves the diagnostic accuracy of pulmonary lesions, but complication rate increases significantly.Advances in knowledge:In general, TCNB should be recommended, especially for highly suspicious benign lesions. For patients with small lesions adjacent to vessels or vessels within the lesion, TANB should be considered.     

Diffusion-weighted MRI of ischemic stroke at 3T: Value of synthetic b-values

Objectives:Diffusion-weighted imaging (DWI) plays a crucial role in the diagnosis of ischemic stroke. We assessed the value of computed and acquired high b-value DWI in comparison with conventional b = 1000 s mm⁻² DWI for ischemic stroke at 3T.Methods:We included 36 patients with acute ischemic stroke who presented with diffusion abnormalities on DWI performed within 24 h of symptom onset. B-values of 0, 500, 1000 and 2000 s mm⁻² were acquired. Synthetic images with b-values of 1000, 1500, 2000 and 2500 s mm⁻² were computed. Two readers compared synthetic (syn) and acquired (acq) b = 2000 s mm⁻² images with acquired b = 1000 s mm⁻² images in terms of lesion detection rate, image quality, presence of uncertain hyperintensities and lesion conspicuity. Readers also selected their preferred b-value. Contrast ratio (CR) measurements were performed. Non-parametrical statistical tests and weighted Cohens’ κ tests were computed.Results:Syn1000 and syn1500 matched acq1000 images in terms of lesion detection rate, image quality and presence of uncertain hyperintensities but presented with significantly improved lesion conspicuity (p < 0.01) and were frequently selected as preferred b-values. Acq2000 images exhibited a similar lesion detection rate and improved lesion conspicuity (p < 0.01) but worse image quality (p < 0.01) than acq1000 images. Syn2000 and syn2500 images performed significantly worse (p < 0.01) than acq1000 images in most or all categories. CR significantly increased with increasing b-values.Conclusion:Synthetic images at b = 1000 and 1500 s mm⁻² and acquired DWI images at b = 2000 s mm⁻² may be of clinical value due to improved lesion conspicuity.Advances in knowledge:Synthetic b-values enable improved lesion conspicuity for DWI of ischemic stroke.     

MR-enterography in Crohn’s disease: what MRE mural parameters are associated to one-year therapeutic management outcome?

Objective:To investigate the association of mural parameters of MR-enterography (MRE) with one-year therapeutic management of Crohn’s disease (CD) patients.Methods:CD patients, undergone MRE with diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) maps between January 2017 and June 2018, were retrospectively enrolled. Extramural complications represented an exclusion criterion because of their potential influence on the intrinsic characteristic of the bowel wall. Two groups of patients were defined on the base of the therapeutic management adopted at 1-year follow-up: Medical-group and surgical-group. The following MRE parameters were evaluated: wall-thickening, longitudinal-extension, T2-fat-suppression-mural-signal, ulcers, mural-oedema, wall-enhancement-rate/pattern, DWI-scores, ADC-values, strictures.Results:70 CD patients were enrolled. 57/70 (81.4%) were included in Medical-group and 13/70 (18.6%) in Surgical-group. ADCmean and strictures resulted to be significantly (p < 0.01) different between the two groups. The ADCmean showed to be significantly associated to conservative management [p < 0.01; OR: 0.0003; 95% CI (0.00–0.13)], while the strictures to surgical management [p < 0.01; OR: 29.7; 95% CI (4.9–179.7)]. ROC curves for ADCmean showed that AUC was 0.717 [95% CI (0.607–0.810), p < 0.01] with an optimal cut-off value of 1.081 × 10⁻³ mm² s⁻¹. A negative predictive value of 90.2% was observed associating ADCmean values > 1.081 × 10⁻³ mm² s⁻¹ to conservative therapy. 13/17 (76%) strictures with an ADCmean > 1.081 × 10⁻³ mm² s⁻¹ benefited of conservative therapy.Conclusion:ADCmean values calculated on DWI-MRE may be associated to 1-year conservative medical therapy in patients with CD without extramural complications.Advances in knowledge:ADC maps may be proposed to select CD patients with a lower burden of mural active inflammatory cells and/or fibrosis benefiting of 1-year conservative treatment.     

Reducing contrast medium dose with low photon energy images in renal dual-energy spectral CT angiography and adaptive statistical iterative reconstruction (ASIR)

Objective:To evaluate the value of using low energy (keV) images in renal dual-energy spectral CT angiography (CTA) and adaptive statistical iterative reconstruction (ASIR) to reduce contrast medium dose.Methods:40 patients with renal CTA on a Discovery CT750HD were randomly divided into two groups: 20 cases (Group A) with 600 mgI kg⁻¹ and 20 cases (Group B) with 300 mgI kg⁻¹. The scan protocol for both groups was: dual-energy mode with mA selection for noise index of 10 HU, pitch 1.375:1, rotating speed 0.6 s/r. Images were reconstructed at 0.625 mm thickness with 40%ASIR, Group A used the conventional 70keV monochromatic images, and Group B used monochromatic images from 40 to 70 keV at 5 keV interval for analysis. The CT values and standard deviation (SD) values of the renal artery and erector spine in the plain and arterial phases were measured with the erector spine SD value representing image noise. The enhancement degree of the renal artery (ΔCT = CT(arterial) -CT(plain)), signal-to-noise ratio (SNR=CT_renal-artery/SD_renal-artery) and contrast-to-noise ratio (CNR=(CT_renal-artery-CT_{erector spine})/SD_{erector-spine}) were calculated. The single factor analysis of variance was used to analyze the difference of ΔCT, SNR and CNR among image groups with p < 0.05 being statistically significant. The subjective image scores of the groups were assessed blindly by two experienced physicians using a 5-point system and the score consistency was compared by the κ test.Results:Contrast medium dose in the 300 mgI kg⁻¹ group was reduced by 50% compared with the 600 mgI kg⁻¹ group, while radiation dose was similar between the two groups. The subjective scores were 4.00 ± 0.65, 4.50 ± 0.60 and 3.70 ± 0.80 for images at 70 keV (600 mgI kg⁻¹ group), 40 keV (300 mgI kg⁻¹ group) and 45 keV (300 mgI kg⁻¹ group), respectively with good consistency between the two reviewers (p > 0.05). The 40 keV images in the 300 mgI kg⁻¹ group had similar ΔCT (469.77 ± 86.95 HU vs 398.54 ± 73.68 HU) and CNR (15.52 ± 3.32 vs 18.78 ± 6.71) values as the 70 keV images in the 600 mgI kg⁻¹) group but higher SNR values (30.19 ± 4.41 vs 16.91 ± 11.12, p < 0,05)Conclusion:Contrast dose may be reduced by 50% while maintaining image quality by using lower energy images combined with ASIR in renal dual-energy CTA.Advances in knowledge:Combined with ASIR and energy spectrum, can reduce the amount of contrast dose in renal CTA.     

Tailored Vessel-Catheter Diameter Ratio in a Direct Aspiration First-Pass Technique: Is It a Matter of Caliber?

BACKGROUND AND PURPOSE:The aspiration technique has gained a prominent role in mechanical thrombectomy. The thrombectomy goal is successful revascularization (modified TICI ≥ 2b) and first-pass effect. The purpose of this study was to evaluate the impact of the vessel-catheter ratio on the modified TICI ≥ 2b and first-pass effect.MATERIALS AND METHODS:This was a retrospective, single-center, cohort study. From January 2018 to April 2020, 111/206 (53.9%) were eligible after applying the exclusion criteria. Culprit vessel diameters were measured by 2 neuroradiologists, and the intraclass correlation coefficient was calculated. The receiver operating characteristic curve was used for assessing the vessel-catheter ratio cutoff for modified TICI ≥ 2b and the first-pass effect. Time to groin puncture and fibrinolysis were weighted using logistic regression. All possible intervals (interval size, 0.1; sliding interval, 0.01) of the vessel-catheter ratio were plotted, and the best and worst intervals were compared using the χ² test.RESULTS:Modified TICI ≥ 2b outcome was achieved in 75/111 (67.5%), and first-pass effect was achieved in 53/75 (70.6%). The MCA diameter was 2.1 mm with an intraclass correlation coefficient of 0.92. The optimal vessel-catheter ratio cutoffs for modified TICI ≥ 2b were ≤1.51 (accuracy = 0.67; 95% CI, 0.58–0.76; P = 0.001), and for first-pass effect, they were significant (≤1.33; P = .31). The modified TICI ≥ 2b odds ratio and relative risk were 9.2 (95% CI, 2.4–36.2; P = 0.002) and 3.2 (95% CI, 1.2–8.7; P = .024). The odds ratio remained significant after logistic regression (7.4; 95% CI, 1.7–32.5; P = .008). First-pass effect odds ratio and relative risk were not significant (2.1 and 1.5; P > .05, respectively). The modified TICI ≥ 2b best and worst vessel-catheter ratio intervals were not significantly different (55.6% versus 85.7%, P = .12). The first-pass effect best vessel-catheter ratio interval was significantly higher compared with the worst one (78.6% versus 40.0%, P = .03).CONCLUSIONS:The aspiration catheter should be selected according to culprit vessel diameter. The optimal vessel-catheter ratio cutoffs were ≤1.51 for modified TICI ≥ 2b with an odds ratio of 9.2 and a relative risk of 3.2.

Stroke represents the second leading cause of death in the world;¹ however, the case fatality rate has decreased in recent decades due to primary prevention and treatment improvements.² After the introduction in various guidelines,^3,4 patients treated with mechanical thrombectomy showed a significant decrease of disability at 90 days compared with controls (OR = 2.49; 95% CI, 1.76–3.53; P < .0001)⁵ and a reduction of decompressive hemicraniectomy for malignant cerebral edema (range, 11.4%–4.8%; P < .001).⁶ Recently, a direct aspiration first-pass technique (ADAPT) has gained a level of I B-R for mechanical thrombectomy in the 2019 guidelines for stroke management.³ An modified TICI (mTICI) of grade 2b/3 is the mechanical thrombectomy goal for increasing good functional outcome;^3,7 in addition, first-pass effects have earned a prominent role in stroke prognosis.⁸Nikoubashman et al⁹ demonstrated, in an experimental animal study, that large-bore catheters should have an inner diameter of >1.016 mm for the MCA and >1.524 mm for the ICA. Moreover, Alawieh et al¹⁰ showed a higher rate of recanalization and first-pass effect using larger diameter catheters versus smaller ones (ACE64/ACE68 [Penumbra] versus 5MAX ACE [Penumbra], 85%/81% versus 61%, P < .05, respectively). However, no differences were found in terms of first-pass effect, reperfusion, and clinical outcome among different large-bore catheters selected (Catalyst 6, Stryker; Sofia, MicroVention; Navien, Covidien; ACE68, Penumbra; P > .05).¹¹The aim of this study was to evaluate the impact of the vessel-catheter ratio on successful revascularization and first-pass effect in a tertiary center (Azienda Ospedaliera San Camillo/Forlanini) for cerebrovascular disease treatment.     

Imaging findings of cutaneous angiosarcoma of the scalp: Comparison with cutaneous squamous cell carcinoma

PurposeThis study aimed to evaluate imaging findings of cutaneous angiosarcoma (cAS) of the scalp compared with those of cutaneous squamous cell carcinoma (cSCC).MethodsThis study included 15 patients with primary cAS and 10 with primary cSCC of the scalp. Seven patients with cAS and eight with cSCC underwent magnetic resonance imaging, and 11 patients with cAS and eight with cSCC underwent ¹⁸F-fluorodeoxyglucose–positron emission tomography/computed tomography imaging. Imaging findings for both pathologies were retrospectively reviewed and compared.ResultsAll 15 cAS cases were elevated lesions with an obtuse angle, invading the subcutaneous fat tissue. Multiple lesions were observed in only five cAS cases (33%) and no cSCC cases. Maximum diameter-to-height ratio was significantly higher in cAS than in cSCC (3.3 ± 1.0 versus 2.3 ± 0.6; p < 0.01). On T2-weighted images, intratumoral hypointensity (86% versus 13%; p < 0.01) and mixed hyper- and hypointensity (71% versus 0%; p < 0.01) were observed more frequently in cAS than in cSCC. No significant differences were observed between cAS and cSCC regarding flow void (29% versus 25%; p = 0.656). Maximum standardized uptake values were marginally significantly lower in cAS than in cSCC (5.6 ± 3.1 versus 10.5 ± 6.6; p = 0.078). ConclusionsCases of cAS of the scalp always exhibited flat elevated lesions with invasion of the subcutaneous fat tissue. Compared with cSCC, intratumoral hypointensity and mixed hyper- and hypointensity on T2-weighted images were more frequent in cAS. These findings will help with the differential diagnosis of cAS.     

Repeatability and reproducibility of apparent diffusion coefficient and fat fraction measurement of focal myeloma lesions on whole body magnetic resonance imaging

Objective:To assess intra- and inter-reader variability of apparent diffusion coefficient (ADC) and fat fraction (FF) measurement in focal myeloma bone lesions and the influence of lesion size.Methods:22 myeloma patients with focal active disease on whole body MRI were included. Two readers outlined a small (5–10 mm) and large lesion (>10 mm) in each subject on derived ADC and FF maps; one reader performed this twice. Intra- and inter-reader agreement for small and large lesion groups were calculated for derived statistics from each map using within-subject standard deviation, coefficient of variation, interclass correlation coefficient measures, and visualized with Bland–Altman plots.Results:For mean ADC, intra- and inter-reader repeatability demonstrated equivalently low coefficient of variation (3.0–3.6%) and excellent interclass correlation coefficient (0.975–0.982) for both small and large lesions. For mean FF, intra- and inter-reader repeatability was significantly poorer for small lesions compared to large lesions (intra-reader within-subject standard variation estimate is 2.7 times higher for small lesions than large lesions (p = 0.0071), and for inter-reader variations is 3.8 times higher (p = 0.0070)).Conclusion:There is excellent intra- and inter-reader agreement for mean ADC estimates, even for lesions as small as 5 mm. For FF measurements, there is a significant increase in coefficient of variation for smaller lesions, suggesting lesions >10 mm should be selected for lesion FF measurement.Advances in knowledge:ADC measurements of focal myeloma have excellent intra- and inter-reader agreement. FF measurements are more susceptible to lesion size as intra- and inter-reader agreement is significantly impaired in lesions less than 10 mm.     

Comparison of 18F-NaF PET/CT with Other Imaging Methods in the Detection of Bone Metastases in Patients with Medullary Thyroid Cancer: a Report of a Series of 31 Cases

PurposeTo compare the ¹⁸F-NaF PET/CT studies (¹⁸F-NaF) with other imaging methods in the detection of skeletal metastases (SM) in patients with medullary thyroid cancer (MTC).MethodsWe retrospectively analyzed 31 patients with MTC who performed ¹⁸F-NaF to assess SM. The results of the ¹⁸F-NaF were compared with other imaging methods performed for metastasis detection: ⁹⁹Tc-MDP bone scan (BS), magnetic resonance imaging (MRI), contrast-enhanced CT (CT), and ⁶⁸Ga-Dotatate and ¹⁸F-FDG PET/CT studies. A qualitative analysis comparing the ¹⁸F-NaF findings with the ones of the other methods was performed, and the results were classified as superior (>), equal (=), and inferior (<).ResultsEleven patients had no bone metastases detected on any of the imaging methods used. Twenty patients presented SM depicted on ¹⁸F-NaF. Of these 20 patients, 12 performed bone scan (in 9 ¹⁸F-NaF > BS and in 3 ¹⁸F-NaF = BS), 1 performed ¹⁸F-FDG (¹⁸F-NaF > ¹⁸F-FDG), 4 performed ⁶⁸Ga-Dotatate (in 2 ¹⁸F-NaF > ⁶⁸Ga-Dotatate and in 2 ¹⁸F-NaF = ⁶⁸Ga-Dotatate), 20 performed CT of at least one body segment (in 15 ¹⁸F-NaF = CT and in 5 ¹⁸F-NaF > CT), and 16 performed MRI of at least one body segment, and in all of them, the ¹⁸F-NaF was equal to the MRI. Beside this, the ¹⁸F-NaF detected SM in body segments not routinely scanned in MRI and CT.ConclusionIn patients with MTC, the ¹⁸F-NaF seems to be equal or superior to other imaging modalities in the detection of SM and allows the analysis of the whole skeletal in a single study.     

Stereotactic body radiation therapy for a new lung cancer arising after pneumonectomy: dosimetric evaluation and pulmonary toxicity

Objective:

To evaluate the tolerance of stereotactic body radiation therapy (SBRT) for the treatment of secondary lung tumours in patients who underwent previous pneumonectomy.

Methods:

12 patients were retrospectively analysed. The median maximum tumour diameter was 2.1 cm (1–4.5 cm). The median planning target volume was 20.7 cm³ (2.4–101.2 cm³). Five patients were treated with a single fraction of 26 Gy and seven patients with fractionated schemes (3 × 10 Gy, 4 × 10 Gy, 4 × 12 Gy). Lung toxicity, correlated with volume (V) of lung receiving >5, >10 and >20 Gy, local control and survival rate were assessed. Median follow-up was 28 months.

Results:

None of the patients experienced pulmonary toxicity > grade 2 at the median dosimetric lung parameters of V₅, V₁₀ and V₂₀ of 23.1% (range 10.7–56.7%), 7.3% (2.2–27.2%) and 2.7% (0.7–10.9%), respectively. No patients required oxygen or had deterioration of the performance status during follow-up if not as a result of clinical progression of disease. The local control probability at 2 years was 64.5%, and the overall survival at 2 years was 80%.

Conclusion:

SBRT appears to be a safe and effective modality for treating patients with a second lung tumour after pneumonectomy.

Advances in knowledge:

Our results and similar literature results show that when keeping V₅, V₁₀ V₂₀ <50%, <20% and <7%, respectively, the risk of significant lung toxicity is acceptable. Our experience also shows that biologically effective dose 10 >100 Gy, necessary for high local control rate, can be reached while complying with the dose constraints for most patients.     

Benefits of using a photostimulable phosphor plate protective device

Objectives:To develop and test a protective device (PD) to increase the resistance of photostimulable storage phosphor (PSP) plate to compressive load, and assess the resulting image quality.Methods:Two prototypes, polyvinylchloride sheets of 0.3 mm and 0.7 mm each, were developed for PSP plate size 2. The resistance to compressive load was tested using eight new PSPs divided into four test groups: (1) PSP, (2) PSP and paperboard protector, (3) PSP and 0.3 mm PD, and (4) PSP and 0.7 mm PD. The resulting images were analyzed by three oral radiologists, based on the consensus for image artifacts. Additionally, the objective image quality test was performed with four new PSPs, using an 8-step wedge aluminum scale. The mean gray values and standard deviation were measured in a total of 240 images, and the data were analyzed using analysis of variance with Bonferroni post-hoc test.Results:Artifacts were seen in the PSP control group starting at 40 n, and at 150 n, 175 n and 300 n in 0.3 mm PD, paperboard protector and 0.7 mm PD, respectively. Although there was no statistical difference among groups, there were differences between exposure times (0.06–0.25 s, 0.06–0.40 s, and 0.10–0.40 s). Scanning resolution of 20 lp/mm showed higher mean gray value than 25 and 40 lp/mm (p < 0.05)Conclusion:The developed PDs improved the PSP resistance to compressive forces, with low interference on the pixel gray values, regardless of exposure time and spatial resolution. Nevertheless, the 0.7 mm PD could withstand the maximum compressive load.     

A review of staging chest CT in trunk and extremity soft tissue sarcoma

Objectives:To determine the incidence of pulmonary metastases on chest CT in trunk and extremity soft tissue sarcoma based on two size criteria, and to identify factors associated with metastases.Methods:Retrospective review of chest CT studies in patients with trunk and extremity soft tissue sarcoma over an 18-month period. Data collected included patient age/sex, tumour location, size and relationship to fascia. All chest CTs were reviewed for the presence of metastases which were diagnosed according to two size criteria: multiple nodules > 5 mm in size or multiple nodules > 10 mm in size. Follow-up CT studies were reviewed in cases initially considered indeterminate.Results:127 males and 73 females were included (mean age 57.1 years; range 10–90 years). 147 (73.5%) tumours were deep to the fascia and 53 (26.5%) superficial. Tumour size classified according to the 12 AJCC 2019 criteria was: T1 = 52, T2 = 76, T3 = 39, T4 = 33. Based on nodule size >5 mm, 73 (36.5%) patients had no metastases, 42 (21%) had metastases, while 85 (42.5%) studies were indeterminate. Based on nodule size >10 mm, 73 (36.5%) patients had no metastases, 28 (14%) had metastases, while 99 (49.5%) studies were indeterminate. Larger maximum dimension of the primary tumour was a risk factor for pulmonary metastases using both size criteria.Conclusion:The incidence of pulmonary metastases at presentation in trunk and extremity soft tissue sarcoma is 14–21%. 42.5–49.5% of chest CTs were indeterminate.Advances in knowledge:The incidence of pulmonary metastases at presentation in trunk and extremity soft tissue sarcoma is 14–21%. Indeterminate pulmonary nodules are also very common.