High-Frequency Jet Ventilation Versus Spontaneous Respiration for Percutaneous Cryoablation of Lung Tumors: Comparison of Adverse Events and Procedural Efficiency

BACKGROUND. High-frequency jet ventilation (HFJV) facilitates accurate probe placement in percutaneous ablation of lung tumors but may increase risk for adverse events, including systemic air embolism. OBJECTIVE. The purpose of this study was to compare major adverse events and procedural efficiency of percutaneous lung ablation with HFJV under general anesthesia to spontaneous respiration (SR) under moderate sedation. METHODS. This retrospective study included consecutive adults who underwent CT-guided percutaneous cryoablation of one or more lung tumors with HFJV or SR between January 1, 2017, and May 31, 2023. We compared major adverse events (Common Terminology Criteria for Adverse Events grade ≥ 3) within 30 days postprocedure and hospital length of stay (HLOS) of 2 days or more using logistic regression analysis. We compared procedure time, room time, CT guidance acquisition time, CT guidance radiation dose, total radiation dose, and pneumothorax using generalized estimating equations. RESULTS. Overall, 139 patients (85 women, 54 men; median age, 68 years) with 310 lung tumors (82% metastases) underwent 208 cryoablations (HFJV, n = 129; SR, n = 79). HFJV showed greater rates than SR for the treatment of multiple tumors per session (43% vs 19%, respectively; p = .02) and tumors in a nonperipheral location (48% vs 24%, p < .001). Major adverse event rate was 8% for HFJV and 5% for SR (p = .46). No systemic air embolism occurred. HLOS was 2 days or more in 17% of sessions and did not differ significantly between HFJV and SR (p = .64), including after adjusting for probe number per session, chronic obstructive pulmonary disease, and operator experience (p = .53). Ventilation modalities showed no significant difference in procedure time, CT guidance acquisition time, CT guidance radiation dose, or total radiation dose (all p > .05). Room time was longer for HFJV than SR (median, 154 vs 127 minutes, p < .001). For HFJV, the median anesthesia time was 136 minutes. Ventilation modalities did not differ in the frequencies of pneumothorax or pneumothorax requiring chest tube placement (both p > .05). CONCLUSION. HFJV appears to be as safe as SR but had longer room times. HFJV can be used in complex cases without significantly impacting HLOS of 2 days or more, procedure time, or radiation exposure. CLINICAL IMPACT. Selection of the ventilation modality during percutaneous lung ablation should be based on patient characteristics and anticipated procedural requirements as well as operator preference.

Factors Associated with Hospital Length of Stay and Adverse Events following Percutaneous Ablation of Lung Tumors

PURPOSE

To explore the association between risk factors established in the surgical literature and hospital length of stay (HLOS), adverse events, and hospital readmission within 30 days after percutaneous image-guided thermal ablation of lung tumors.

MATERIALS AND METHODS

This bi-institutional retrospective cohort study included 131 consecutive adult patients (67 men [51%]; median age, 65 years) with 180 primary or metastatic lung tumors treated in 131 sessions (74 cryoablation and 57 microwave ablation) from 2006 to 2019. Age-adjusted Charlson Comorbidity Index, sex, performance status, smoking status, chronic obstructive pulmonary disease (COPD), primary lung cancer versus pulmonary metastases, number of tumors treated per session, maximum axial tumor diameter, ablation modality, number of pleural punctures, anesthesia type, pulmonary artery-to-aorta ratio, lung densitometry, sarcopenia, and adipopenia were evaluated. Associations between risk factors and outcomes were assessed using univariable and multivariable generalized linear models.

RESULTS

In univariable analysis, HLOS was associated with current smoking (incidence rate ratio [IRR], 4.54 [1.23-16.8]; P = .02), COPD (IRR, 3.56 [1.40-9.04]; P = .01), cryoablations with ≥3 pleural punctures (IRR, 3.13 [1.07-9.14]; P = .04), general anesthesia (IRR, 10.8 [4.18-27.8]; P < .001), and sarcopenia (IRR, 2.66 [1.10-6.44]; P = .03). After multivariable adjustment, COPD (IRR, 3.56 [1.57-8.11]; P = .003) and general anesthesia (IRR, 12.1 [4.39-33.5]; P < .001) were the only risk factors associated with longer HLOS. No associations were observed between risk factors and adverse events in multivariable analysis. Tumors treated per session were associated with risk of hospital readmission (P = .03).

CONCLUSIONS

Identified preprocedural risk factors from the surgical literature may aid in risk stratification for HLOS after percutaneous ablation of lung tumors, but were not associated with adverse events.

A novel core biopsy needle with shorter dead space for percutaneous image-guided musculoskeletal biopsies - how does it compare with an established core biopsy needle?

PURPOSE

To compare diagnostic yield and utility of a novel core biopsy needle (NCBN) with shortened tip dead space for percutaneous musculoskeletal biopsies with an established core biopsy needle (ECBN).

METHODS

This study was IRB approved and HIPAA compliant. All percutaneous biopsies using an NCBN performed between July 2020 and August 2021 were retrospectively reviewed. Data on patient demographics, biopsy technique, biopsy needle, and histopathology were collated.

RESULTS

Thirty-six patients were included in this study, 16 (44%) undergoing biopsy with both an NCBN and an ECBN, and 20 (56%) with an NCBN only. All 36 NCBN biopsies were 16 gauge. Fifteen (94%) of the ECBN biopsies were 14 gauge, and 1 (6%) was 16 gauge. Thirty-four (94%) of the NCBN and 15 (94%) of the ECBN biopsies were diagnostic. No adverse events were identified.

CONCLUSION

Both the NCBN and ECBN have high diagnostic rates. No adverse events were identified. NCBN could be considered for biopsy of lesions limited by anatomic location or near adjacent critical structures.

Axillary Anatomy and Pathology: Pearls and "Pitfalls" for Thoracic Imagers

The axilla contains several important structures which exist in a relatively confined anatomic space between the neck, chest wall, and upper extremity. While neoplastic lymphadenopathy may be among the most common axillary conditions, many other processes may be encountered. For example, expanded use of axillary vessels for access routes for endovascular procedures will increase the need for radiologists to access vessel anatomy, patency, and complications that may arise. Knowledge of axillary anatomy and pathology will allow the imager to systematically evaluate the axillae using various imaging modalities.

The role of percutaneous CT-guided biopsy of an adrenal lesion in patients with known or suspected lung cancer

PURPOSE

To determine the sensitivity, specificity, and complication rate of percutaneous adrenal biopsy in patients with known or suspected lung cancer.

METHODS

This study was approved by the Institutional Review Board at our institution as a retrospective analysis; therefore, the need for informed consent was waived. All percutaneous adrenal biopsies performed between April 1993 and May 2019 were reviewed. 357 of 582 biopsies were performed on 343 patients with known or suspected lung cancer (M:F 164:179; mean age 66 years). The biopsy results were classified into malignant, benign, or non-diagnostic. The final diagnosis was established by pathology (biopsy and/or surgical resection) or imaging follow-up on CT for at least 12 months following the biopsy. Patients with less than 12 months follow-up were excluded (n = 44). Complications were recorded.

RESULTS

The final diagnosis was metastatic lung cancer in 235 cases (77.8%), metastasis from an extrapulmonary primary in 2 cases (0.7%), pheochromocytoma in 2 cases (0.7%), and benign lesions in 63 cases (20.9%). Percutaneous adrenal gland biopsy had a sensitivity of 97% and specificity of 100% for lung cancer metastases. The non-diagnostic rate was 0.6%. Larger lesions were more likely to be malignant (p = 0.0000) and to be correctly classified as a lung metastasis (p = 0.025). The incidence of minor complications was 1.1%. There were no major complications.

CONCLUSION

Over 20% of adrenal lesions in patients with known or suspected lung cancer were not related to lung cancer. Percutaneous adrenal gland biopsy is a safe procedure, with high sensitivity and specificity for lung cancer metastases.

Outcomes Following Percutaneous Microwave and Cryoablation of Lung Metastases from Adenoid Cystic Carcinoma of the Head and Neck: A Bi-Institutional Retrospective Cohort Study

OBECTIVE

The aim of this study was to report outcomes following percutaneous microwave and cryoablation of lung metastases from adenoid cystic carcinoma (ACC) of the head and neck.

MATERIAL AND METHODS

This bi-institutional retrospective cohort study included 10 patients (6 females, median age 59 years [range 28-81]) who underwent 32 percutaneous ablation sessions (21 cryoablation, 11 microwave) of 60 lung metastases (median 3.5 tumors per patient [range 1-16]) from 2007 to 2019. Median tumor diameter was 16 mm [range 7-40], significantly larger for cryoablation (22 mm, p = 0.002). A median of two tumors were treated per session [range 1-7]. Technical success, local control, complications, and overall survival were assessed.

RESULTS

Primary technical success was achieved for 55/60 tumors (91.7%). Median follow-up was 40.6 months (clinical) and 32.5 months (imaging, per tumor). Local control at 1, 2, and 3 years was 94.7%, 80.8%, and 76.4%, respectively, and did not differ between ablation modalities. Five of fifteen recurrent tumors underwent repeat ablation, and secondary technical success was achieved in four (80%). Assisted local tumor control at 1, 2, and 3 years was 96.2%, 89.8%, and 84.9%, respectively. Complications occurred following 24/32 sessions (75.0%) and 57.2% Common Terminology Criteria for Adverse Events (CTCAE) lower than grade 3. Of 13 pneumothoraces, 7 required chest tube placements. Hemoptysis occurred after 7/21 cryoablation sessions, and bronchopleural fistula developed more frequently with microwave (p = 0.037). Median length of hospital stay was 1 day [range 0-10], and median overall survival was 81.5 months (IQR 40.4-93.1).

CONCLUSION

Percutaneous computed tomography-guided microwave and cryoablation can treat lung metastases from ACC of the head and neck. Complications are common but manageable, with full recovery expected.

Arterial diameter following arteriovenous fistula creation predicts aneurysm progression

OBJECTIVE

To investigate the relationship between arteriovenous fistula (AVF) arterial diameter (AD) and AVF aneurysm development and progression.

METHODS

This study identified all patients who underwent fistulograms which demonstrated AVF aneurysms meeting criteria and requiring surgical intervention between 01/01/2014 and 7/30/2016. Patient demographics were collected and AVF dimensions were measured on fistulograms. A control group with nonaneurysmal AVFs who had undergone serial fistulograms between 2013 and 2016 were identified and identical datasets collected. Statistical analysis was performed with STATA 14.0 using student's t-test, Chi square tests and linear regression.

RESULTS

45 eligible patients were identified in the AVF aneurysm study group and 24 in the control group, with the mean age of AVF creation being older in the control group (61.8 vs 53 years, p = 0.03). The mean interval between AVF creation and first fistulogram in the study group was 1464 ± 282 days, compared to an interval of 263 ± 101 days in the control group (p = 0.003). The AD on the first fistulogram in those study group patients with aneurysms evident on first fistulogram was greater than in the control group (6.5±1.8 mm vs 5.0 ± 1.8 mm, p = 0.003). The AD on first fistulogram of the study group predicted maximum aneurysm diameter on last fistulogram (r = 0.6, p = 0.03) as well as the interval between first fistulogram and surgical revision (r = -0.33, p = 0.03).

CONCLUSION

AVF aneurysms are a later complication in access natural history and AD may help to predict their progression.

Pre-hepatic and pre-pancreatic transplant donor evaluation

Innovations in surgical techniques coupled with advances in medical and pharmacological management in the past few decades have enabled organ transplantation to become integral to the management of end stage organ failure. In this review article, we will review the role of the radiologist in the work up of liver and pancreas donors during evaluation of their donor candidacy. The critical role of imaging in assessing the parenchymal, biliary and vascular anatomy in liver donor candidates will be reviewed, as well as highlighting the anatomical findings that may pose a contraindication to transplantation. The limited role of imaging in pancreas donor evaluation is also covered, as well as a brief overview of the surgical techniques available and how the radiologist's findings influence operative technique selection.

C-arm cone-beam CT parenchymal blood volume imaging for transarterial chemoembolization of hepatocellular carcinoma: implications for treatment planning and response

We report on the feasibility of C-arm cone-beam computed tomography (CBCT) parenchymal blood volume imaging (PBVI) performed immediately following transarterial chemoembolization (TACE) of hepatocellular carcinoma (HCC) to assess the need for repeat treatment. Eighteen TACE procedures were included. A retrospective assessment was made for the presence or absence of residual disease requiring treatment on immediate post-TACE PBVI and on interval follow-up multidetector computed tomography (MDCT) or magnetic resonance imaging (MRI). In 9/18 cases, both PBVI and MDCT/MRI showed that no further treatment was required. In 6/18 cases, further treatment was required on both PBVI and MDCT/MRI. In three cases, PBVI showed that further treatment was not required but MDCT/MRI showed residual disease requiring repeat treatment. There were no cases with PBVI showing residual disease not detected on follow-up MDCT/MRI. The PBVI sensitivity for detecting disease requiring repeat TACE was 67% (95% confidence interval [CI] 30-93%), and specificity was 100% (95% CI 66-100%). The use of C-arm CBCT PBVI for the detection of residual viable tumor within a treated lesion immediately after TACE is feasible. It may allow repeat TACE to be planned without performing interval imaging with MDCT or MRI.

Computed tomography texture features can discriminate benign from malignant lymphadenopathy in pediatric patients: a preliminary study

BACKGROUND

Differentiation of benign from malignant lymphadenopathy remains challenging in pediatric radiology. Textural analysis (TA) quantitates heterogeneity of tissue signal intensities and has been applied to analysis of CT images.

OBJECTIVE

The purpose of this study was to establish whether CT textural analysis of enlarged lymph nodes visualized on pediatric CT can distinguish benign from malignant lymphadenopathy.

MATERIALS AND METHODS

We retrospectively identified enlarged lymph nodes measuring 10-20 mm on contrast-enhanced CTs of patients age 18 years and younger that had been categorized as benign or malignant based on the known diagnoses. We placed regions of interest (ROIs) over lymph nodes of interest and performed textural analysis with and without feature size filtration. We then calculated test performance characteristics for TA features, along with multivariate logistic regression modeling using Akaike Information Criterion (AIC) minimization, to determine the optimal thresholds for distinguishing benign from malignant lymphadenopathy.

RESULTS

We identified 34 enlarged malignant nodes and 29 benign nodes from 63 patients within the 10- to 20-mm size range. Filtered image TA exhibited 82.4% sensitivity, 86.2% specificity and 84.1% accuracy for detecting malignant lymph nodes using mean and entropy parameters, whereas unfiltered TA exhibited 88.2% sensitivity, 72.4% specificity and 81.0% accuracy using mean and mean value of positive pixels parameters.

CONCLUSION

This preliminary study demonstrates that the use of TA features improves the utility of pediatric CT to distinguish benign from malignant lymphadenopathy. The addition of TA to pediatric CT protocols has great potential to aid the characterization of indeterminate lymph nodes. If definitive differentiation between benign and malignant lymphadenopathy is possible by TA, it has the potential to reduce the need for follow-up imaging and tissue sampling, with reduced associated radiation exposure. However future studies are needed to confirm the clinical applicability of TA in distinguishing benign from malignant lymphadenopathy.

Radiation Dose and Risk Estimates of CT-Guided Percutaneous Liver Ablations and Factors Associated with Dose Reduction

PURPOSE

To determine the radiation dose associated with CT-guided percutaneous liver ablations and identify potential risk factors that result in higher radiation doses.

MATERIALS AND METHODS

Between June 2011 and June 2015, 245 consecutive patients underwent 304 CT-guided liver ablation treatments. Patient demographics, tumor characteristics and procedural parameters were identified and analyzed. The peak skin dose and effective dose were assessed for each procedure. Excess relative risk related to radiation effects was calculated. A logistic regression model was prepared by means of stepwise logistic regression to identify variables predictive of increased radiation exposure.

RESULTS

Tumor ablations were performed with microwave (n = 220), radiofrequency (n = 74) or irreversible electroporation (IRE) (n = 10). The mean peak skin dose for ablations was 239.2 ± 136.4 mGy, and the mean effective dose was 36.6 ± 22.3 mSv. Of the patient and procedural parameters that were analyzed, increasing weight, use of intravenous contrast and/or hydrodissection during the procedure, together with treatment of multiple lesions in the same sitting were all associated with higher radiation exposure. The mean increase in the absolute risk of fatal malignancy from a single procedure was 0.18% (range 0.02-0.9%). No deterministic skin changes were identified in the patient cohort.

CONCLUSION

The overall risk of stochastic and deterministic effects from radiation associated with CT-guided ablations is low compared with other inherent procedural complications. This study identifies several factors that are associated with higher radiation dose in percutaneous liver ablation procedures.

The Diagnostic Accuracy of Contrast-Enhanced CT of the Neck for the Investigation of Sialolithiasis

BACKGROUND AND PURPOSE

Sialolithiasis is a common benign pathology affecting the salivary glands but it is unclear if contrast-enhanced CT, which is commonly used for investigation of head and neck pathology, can identify calculi as accurately as noncontrast CT. The aim of this study was to assess the diagnostic accuracy of contrast-enhanced CT of the neck in the diagnosis of sialolithiasis compared with noncontrast CT of the neck used as the criterion standard.

MATERIALS AND METHODS

This was a retrospective, case-control study of 92 consecutive cases in 90 patients who underwent both noncontrast CT of the neck and contrast-enhanced CT of the neck in 2 tertiary referral centers from January 2011 to December 2015 for investigation of sialolithiasis. Axial 3-mm-section images were assessed by a fellowship-trained diagnostic neuroradiologist and diagnostic neuroradiology fellow in consensus. Blinded assessment of the contrast-enhanced CT of the neck was performed first, followed by noncontrast CT of the neck after a 2-week interval. The presence or absence of a stone and stone location and size were documented. Statistical analysis was undertaken to assess the agreement between CT protocols and calculate the sensitivity and specificity of contrast-enhanced CT of the neck.

RESULTS

Fifty calculi were identified on noncontrast CT of the neck in 31 cases; and 48 calculi, in 31 cases on contrast-enhanced CT of the neck. No calculi were identified in the remaining 61 cases. The sensitivity and specificity of contrast-enhanced CT of the neck in the detection of sialolithiasis was 96% (95% CI, 86.3%-99.5%) and 100% (95% CI, 94.1%-100%), respectively. The positive predictive value of contrast-enhanced CT of the neck was 100% (95% CI, 92.6%-100%), and the negative predictive value was 96.8% (95% CI, 89%-99.6%). The accuracy of contrast-enhanced CT of the neck in diagnosing the presence or absence of salivary calculi was 98%.

CONCLUSIONS

Contrast-enhanced CT of the neck is accurate in the detection of sialolithiasis, with no difference in diagnostic accuracy compared with noncontrast CT of the neck.

Which is the best current guideline for the diagnosis and management of cystic pancreatic neoplasms? An appraisal using evidence-based practice methods

BACKGROUND AND AIM

Cystic pancreatic neoplasms (CPNs) are an increasingly diagnosed entity. Their heterogeneity poses complex diagnostic and management challenges. Despite frequently encountering these entities, particularly in the context of the increased imaging of patients in modern medicine, doctors have to rely on incomplete and ambiguous published literature. The aim of this project was to review the guidelines relating to CPNs using evidence-based practice (EBP) methods.

METHODS

A search of both the primary and secondary literature was performed. Five sets of guidelines were identified which were then methodologically appraised by the AGREE II instrument, a validated and widely utilised tool for guideline development assessment.

RESULTS

The 2014 'Italian consensus guidelines for the diagnostic work-up and follow-up of cystic pancreatic neoplasms' were found to be the most methodologically sound guidelines, on the basis of both the overall score and average weighted domain score.

CONCLUSIONS

The current best guidelines were identified. The Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument can be used for retrospective review of published guidelines or as a roadmap for guideline-writing groups. All guidelines found were methodologically limited. Further longitudinal/prospective studies are required to improve the level of evidence.

KEY POINTS

• Cystic pancreatic neoplasms (CPNs) are an increasingly encountered entity in modern medicine. • Clinical uncertainty remains with regard to optimal diagnostic and management strategies. • The Italian consensus guidelines for cystic pancreatic neoplasms are currently the best guidelines.

Gastrointestinal Erdheim-Chester disease

We report a rare case of Erdheim-Chester Disease, a non-Langerhans cell histiocytosis. A 60-year old female presented with a seven-month history of vague abdominal symptoms. A large retroperitoneal mass was detected on computed tomography (CT), but multiple CT-guided biopsy samples were inconclusive. Laparoscopy revealed a mass in the distal ileum, which was resected. Histology and immuno-histochemistry supported a diagnosis of Erdheim-Chester Disease.