Faculty Bibliography

Purpose: The aim of this prospective study is to investigate the effectiveness and safety of CT-guided percutaneous cryoablation of intercostal nerves for the treatment of postthoracotomy pain syndrome (PTPS). Materials: In this IRB-approved HIPAA compliant single-center study, eighteen patients with refractory post thoracotomy pain were recruited prospectively to receive CT-guided cryoablation between 2009 to 2013. Percutaneous ablations were performed with a PerCryo 17R device. The median patient age was 65.5 years (50-80), and 33% of patients were female. Pain level on a visual analog scale (scores 0-10) was recorded before and immediately after the procedure, as well as at 1 week, 1, 2, 3, 6, 9 and 12 months after the procedure. Complications if any were documented. 6 patients received repeat treatment within the 12-month follow-up period, and their preprocedural pain scores were used for analysis at follow-up time after the repeat treatment.
Result(s): Mean pain levels were 9.2 (95% CI 8.7-9.8) before interventions, and 0.28 (95%CI -0.13-0.69), 3.8 (95%CI 2.2-5.4), 4.8 (95% CI 3.3-6.4), 5.8 (95%CI 4.3-7.3), 6.9 (95%CI 5.4-8.3), 7.9 (95%CI 6.4-9.4) and 8.4 (95%CI 7.0-9.7) immediately after interventions, and at 1 week, 1, 3, 6, 9 and 12 months afterward. A Wilcoxon rank-sum test were performed and showed a statically significantly decreased pain level immediately after until 9 months after the procedures (P = 0.0001-0.042), but not at 12 months (P = 0.206). No procedure related complications were observed.
Conclusion(s): Cryoneurolysis is a safe and effective treatment option for chronic intercostal pain control up to 9 months. Repeat therapy may be considered for longer pain control.
Copyright

Purpose: To describe our experience with lung cryoablation and factors impacting procedural outcomes. Materials: We performed a retrospective review of all percutaneous lung cryoablation patients done at a single institution between August 2017 and May 2019. Procedures were performed using computed tomographic guidance and triple freeze-thaw protocol. Complications and intraprocedural imaging features of the ice balls were recorded. Tumor progression was determined via World Health Organization guidelines. Overall survival was calculated using Kaplan-Meier analysis.
Result(s): A total of 39 patients (mean age, 75.1 years; range 40-94 years), 61.5% (25/39) of whom were female, underwent a total of 45 procedures. The mean follow-up time was 398.4 days (range, 34-746). The mean pre-ablation size of the lung cancer was 19.0 x 13.4 mm. 48.9% (22/45) of tumors were ground glass or part solid. An average of 1.3 probes (range, 1-3) were used for each case (1.4 probe per cm of tumor). 5 cases were performed with a round 2.1 cm diameter ice device, while 40 were performed with an ovoid 2.1 cm diameter device. The immediate post ablation zone measured an average of 28.0 x 21.2 mm (range, 9.4-62.5 mm). At 1-month follow-up, the ablation zone measured 29.3 x 19.3 mm (range, 14.3-47.0 mm). Pneumothorax was the most common complication seen in 46.7% (21/45) of cases. Chest tube placement was required in 33.3% (15/45) of cases. Local recurrence was seen in 6.7% (3/45) of lesions during the follow-up period. There were no 30-day mortalities; however, there were 6 deaths recorded (15.3%) during the study period. 83.3% (5/6) of the deaths were patients with solid tumors. Mean tumor size in these patients was 21.8 x 17.3 mm (range, 15.0-33.0 mm). Mean overall survival probability by Kaplan-Meier was 88.8% (SE: 0.05) at 1 year and 73.2% (SE: 1.4) at 2 years.
Conclusion(s): Lung cryoablation remains a safe and effective therapy option for patients with early stage malignant lung tumors, including both ground glass and part solid tumors. Current cryoablation technologies provide adequate ablation zones for tumors up to 2.0 cm.
Copyright

OBJECTIVE:Guideline-concordant follow-up of incidental lung nodules (ILNs) is suboptimal. We aimed to improve communication and tracking for follow-up of these common incidental findings detected on imaging examinations. METHODS:We implemented a process improvement program for reporting and tracking ILNs at a large urban academic health care system. A multidisciplinary committee designed, tested, and implemented a multipart tracking system in the electronic health record (EHR) that included Fleischner Society management recommendations for each patient. Plan-do-study-act cycles addressed gaps in the follow-up of ILNs, broken into phases of developing and testing components of the conceived EHR toolkit. RESULTS:The program resulted in standardized text macros with discrete categories and recommendations for ILNs, with ability to track each case in a work list within the EHR. The macros incorporated evidence-based guidelines and also input of collaborating clinical referrers in the respective specialty. The ILN macro was used 3,964 times over the first 2 years, increasing from 104 to over 300 uses per month. Usage spread across all subspecialty divisions, with nonthoracic radiologists currently accounting for 80% (56 of 70) of the radiologists using the system and 31% (1,230 of 3,964) of all captured ILNs. When radiologists indicated ILNs as warranting telephone communication to provider offices, completion was documented in 100% of the cases captured in the EHR-embedded tracking report. CONCLUSION/CONCLUSIONS:An EHR-based system for managing incidental nodules enables case tracking with exact recommendations, provider communication, and completion of follow-up testing. Future efforts will target consistent radiologist use of the system and follow-up completion.

INTRODUCTION/BACKGROUND:Communication and physician burn out are major issues within Radiology. This study is designed to determine the utilization and cost benefit of a hybrid computer/human communication tool to aid in relay of clinically important imaging findings. MATERIAL AND METHODS/METHODS:Analysis of the total number of tickets, (requests for assistance) placed, the type of ticket and the turn-around time was performed. Cost analysis of a hybrid computer/human communication tool over a one-year period was based on human costs as a multiple of the time to close the ticket. Additionally, we surveyed a cohort of radiologists to determine their use of and satisfaction with this system. RESULTS:14,911 tickets were placed in the 6-month period, of which 11,401 (76.4%) were requests to "Get the Referring clinician on the phone." The mean time to resolution (TTR) of these tickets was 35.3 (±17.4) minutes. Ninety percent (72/80) of radiologists reported being able to interpret a new imaging study instead of waiting to communicate results for the earlier study, compared to 50% previously. 87.5% of radiologists reported being able to read more cases after this system was introduced. The cost analysis showed a cost savings of up to $101.12 per ticket based on the length of time that the ticket took to close and the total number of placed tickets. CONCLUSIONS:A computer/human communication tool can be translated to significant time savings and potentially increasing productivity of radiologists. Additionally, the system may have a cost savings by freeing the radiologist from tracking down referring clinicians prior to communicating findings.

The left ventricular outflow tract (LVOT) velocity time integral (VTI) is an easily measured echocardiographic stroke volume index analog. Low values predict adverse outcomes in left ventricular failure. We postulate the left ventricular VTI may be a signal of right ventricular dysfunction in acute pulmonary embolism, and therefore a predictor of poor outcomes. We retrospectively reviewed echocardiograms on all Pulmonary Embolism Response Team activations at our institution at the time of pulmonary embolism diagnosis. Low LVOT VTI was defined as ⩽ 15 cm. We examined two composite outcomes: (1) in-hospital death or cardiac arrest; and (2) shock or need for primary reperfusion therapies. Sixty-one of 188 patients (32%) had a LVOT VTI of ⩽ 15 cm. Low VTI was associated with in-hospital death or cardiac arrest (odds ratio (OR) 6, 95% CI 2, 17.9; p = 0.0014) and shock or need for reperfusion (OR 23.3, 95% CI 6.6, 82.1; p < 0.0001). In a multivariable model, LVOT VTI ⩽ 15 remained significant for death or cardiac arrest (OR 3.48, 95% CI 1.02, 11.9; p = 0.047) and for shock or need for reperfusion (OR 8.12, 95% CI 1.62, 40.66; p = 0.011). Among intermediate-high-risk patients, low VTI was the only variable associated with the composite outcome of death, cardiac arrest, shock, or need for reperfusion (OR 14, 95% CI 1.7, 118.4; p = 0.015). LVOT VTI is associated with adverse short-term outcomes in acute pulmonary embolism. The VTI may help risk stratify patients with intermediate-high-risk pulmonary embolism.

PURPOSE/OBJECTIVE:To develop natural language processing (NLP) to identify incidental lung nodules (ILNs) in radiology reports for assessment of management recommendations. METHOD AND MATERIALS/METHODS:We searched the electronic health records for patients who underwent chest CT during 2014 and 2017, before and after implementation of a department-wide dictation macro of the Fleischner Society recommendations. We randomly selected 950 unstructured chest CT reports and reviewed manually for ILNs. An NLP tool was trained and validated against the manually reviewed set, for the task of automated detection of ILNs with exclusion of previously known or definitively benign nodules. For ILNs found in the training and validation sets, we assessed whether reported management recommendations agreed with Fleischner Society guidelines. The guideline concordance of management recommendations was compared between 2014 and 2017. RESULTS:The NLP tool identified ILNs with sensitivity and specificity of 91.1% and 82.2%, respectively, in the validation set. Positive and negative predictive values were 59.7% and 97.0%. In reports of ILNs in the training and validation sets before versus after introduction of a Fleischner reporting macro, there was no difference in the proportion of reports with ILNs (108 of 500 [21.6%] versus 101 of 450 [22.4%]; P = .8), or in the proportion of reports with ILNs containing follow-up recommendations (75 of 108 [69.4%] versus 80 of 101 [79.2%]; P = .2]. Rates of recommendation guideline concordance were not significantly different before and after implementation of the standardized macro (52 of 75 [69.3%] versus 60 of 80 [75.0%]; P = .43). CONCLUSION/CONCLUSIONS:NLP reliably automates identification of ILNs in unstructured reports, pertinent to quality improvement efforts for ILN management.

PURPOSE/OBJECTIVE:To determine the utility of an automated radiology-pathology feedback tool. METHODS:We previously developed a tool that automatically provides radiologists with pathology results related to imaging examinations they interpreted. The tool also allows radiologists to mark the results as concordant or discordant. Five abdominal radiologists prospectively scored their own discordant results related to their previously interpreted abdominal ultrasound, CT, and MR interpretations between August 2017 and June 2018. Radiologists recorded whether they would have followed up on the case if there was no automated alert, reason for the discordance, whether the result required further action, prompted imaging rereview, influenced future interpretations, enhanced teaching files, or inspired a research idea. RESULTS:There were 234 total discordances (range 30-66 per radiologist), and 70.5% (165 of 234) of discordances would not have been manually followed up in the absence of the automated tool. Reasons for discordances included missed findings (10.7%; 25 of 234), misinterpreted findings (29.1%; 68 of 234), possible biopsy sampling error (13.3%; 31 of 234), and limitations of imaging techniques (32.1%; 75/234). In addition, 4.7% (11 of 234) required further radiologist action, including report addenda or discussion with referrer or pathologist, and 93.2% (218 of 234) prompted radiologists to rereview the images. Radiologists reported that they learned from 88% (206 of 234) of discordances, 38.6% (90 of 233) of discordances probably or definitely influenced future interpretations, 55.6% (130 of 234) of discordances prompted the radiologist to add the case to his or her teaching files, and 13.7% (32 of 233) inspired a research idea. CONCLUSION/CONCLUSIONS:Automated pathology feedback provides a valuable opportunity for radiologists across experience levels to learn, increase their skill, and improve patient care.

Extracorporeal membrane oxygenation (ECMO) is known to alter drug pharmacokinetics (PK). The PK changes can result from drug binding to the oxygenator, alterations in clearance, and drug adsorption or sequestration, but the published literature is with old equipment and oxygenators. There is limited data regarding the impact of the oxygenator on drug changes in ECMO circuits in comparison to the other components of the ECMO circuit. The purpose of this study was to determine the impact of the Quadrox-i adult oxygenators on the PK of voriconazole (VOR) in contemporary ECMO circuits. A 3/8-in. closed loop ECMO circuit was prepared with Quadrox-i adult oxygenator (Getinge) and one circuit without an oxygenator in series. The circuits were primed with (whole blood), tromethamine, heparin, calcium gluconate and pH was balanced to 7.35-7.45. VOR was added to the continuously flowing circuits and levels were obtained pre-and post-oxygenator or 2 samples from circuit without oxygenator at the following time intervals; 5 mins, 1, 2, 3, 4, 5, 6 and 24 hrs. VOR control was maintained in a glass vial and samples obtained at the same time periods. There was significant VOR loss in the 3/8-inch circuit with an oxygenator and no apparent VOR loss in the 3/8-inch circuit without an oxygenator. The drug loss started by 2 hours (~20%) and continued over 24-hours (~40%). VOR control showed no loss suggesting the VOR loss was not due to self-degradation. Additional studies are needed to determine dosing regimen alterations for VOR with an ECMO circuit

Markov random field (MRF) has been widely used to incorporate a priori knowledge as penalty or regularizer to preserve edge sharpness while smoothing the region enclosed by the edge for pieces-wise smooth image reconstruction. In our earlier study, we proposed a type of MRF reconstruction method for low-dose CT (LdCT) scans using tissue-specific textures extracted from the same patient's previous full-dose CT (FdCT) scans as prior knowledge. It showed advantages in clinical applications. This paper aims to remove the constraint of using previous data of the same patient. We investigated the feasibility of extracting the tissue-specific MRF textures from an FdCT database to reconstruct a LdCT image of another patient. This feasibility study was carried out by experiments designed as follows. We constructed a tissue-specific MRF-texture database from 3990 FdCT scan slices of 133 patients who were scheduled for lung nodule biopsy. Each patient had one FdCT scan (120 kVp/100 mAs) and one LdCT scan (120 kVp/20 mAs) prior to biopsy procedure. When reconstructing the LdCT image of one patient among the 133 patients, we ranked the closeness of the MRF-textures from the other 132 patients saved in the database and used them as the a prior knowledge. Then, we evaluated the reconstructed image quality using Haralick texture measures. For any patient within our database, we found more than eighteen patients' FdCT MRF texures can be used without noticeably changing the Haralick texture measures on the lung nodules (to be biopsied). These experimental outcomes indicate it is promising that a sizable FdCT texture database could be used to enhance Bayesian reconstructions of any incoming LdCT scans.