Faculty Bibliography

BACKGROUND: Lobectomy is the standard therapy for patients with stage I non-small cell lung cancer (NSCLC). Recently, sublobar resections (SLR), radiofrequency ablation (RFA), and percutaneous cryablation therapy (PCT) for high-risk patients unfit for standard resection have been reported. This study compares all 3 modalities in stage I NSCLC. STUDY DESIGN: Patients with biopsied stage I NSCLC determined by PET/CT deemed medically unfit for standard resection were reviewed by a tumor board according to American College of Surgeons Oncology Group/NIH inoperability criteria before being offered SLR, RFA, or PCT under anesthesia. Patients were followed with CT scans alternating with PET scans. The primary end points were overall survival, cancer-specific survival, and cancer-free survival. Kaplan-Meier analysis and log-rank tests were used. RESULTS: Sixty-four patients underwent SLR (n = 25; 11 men, 13 women; median age 66 years, range 49 to 85 years), RFA (n = 12; 8 men, 4 women; median age 74 years, range 62 to 83 years), and PCT (n = 27; 16 men, 11 women; median age 74 years; range 59 to 88 years). The probability of 3-year survival for the SLR, RFA, and PCT groups was 87.1%, 87.5%, and 77%, respectively (p > 0.05). The 3-year cancer-specific and cancer-free survival for SLR, RFA, and PCT groups was 90.6% and 60.8% versus 87.5% and 50% versus 90.2% and 45.6%, respectively. CONCLUSIONS: This experience suggests comparable survival after sublobar resections and ablative therapies at 3 years. Ablative therapies appear to be a reasonable alternative in high-risk patients not fit for surgery. However, larger randomized studies with longer follow-up are needed to make recommendations for therapy.

RATIONALE AND OBJECTIVES: The aim of this study was to determine the effect of cryoablation on pain levels in patients with histories of post-thoracotomy pain syndrome. MATERIALS AND METHODS: Eighteen patients were included in this retrospective review. Preprocedural and immediate postprocedural pain scores were recorded, as well as several months after the procedures. RESULTS: The average preprocedural pain score was 7.5 +/- 2.0, which decreased to 1.2 +/- 1.9 immediately after the procedure. After a mean follow-up period of 51 days, the average pain score was 4.1 +/- 1.7. The difference between preprocedural and postprocedural pain scores was statistically significant by Wilcoxon's rank sum test. CONCLUSION: Cryoneurolysis of the intercostal nerves statistically significantly decreased pain scores in patients with post-thoracotomy pain syndrome.

We report the use of a multi-layer printed coil circuit for powering (36-94 mW) an implantable microbolus infusion pump (MIP) that can be activated remotely for use in drug infusion in nontethered, freely moving small animals. This implantable device provides a unique experimental tool with applications in the fields of animal behavior, pharmacology, physiology, and functional brain imaging. Two different designs are described: a battery-less pump usable when the animal is inside a home-cage surrounded by a primary inductive coil and a pump powered by a rechargeable battery that can be used for studies outside the home-cage. The use of printed coils for powering of small devices by inductive power transfer presents significant advantages over similar approaches using hand-wound coils in terms of ease of manufacturing and uniformity of design. The high efficiency of a class-E oscillator allowed powering of the minipumps without the need for close physical contact of the primary and secondary coils, as is currently the case for most devices powered by inductive power transfer.

BACKGROUND: Visualization of a posterior junction line (PJL) on chest x-ray is evidence for emphysema. The correlation between the assessment of the PJL on computed tomography (CT) and emphysema is less clear. METHODS: One hundred thirty-seven patients were identified with CT and pulmonary function tests (PFTs) performed within 3 months of each other in a University hospital. The width of the PJL was measured at 2 levels by a blinded investigator: superiorly at the superior border of the aorta and inferiorly 2 cm below the aortic arch. This was correlated to clinical and PFT data and to CT evidence of emphysema. RESULTS: Narrowness of the junction line showed poor correlation with PFT findings of emphysema as assessed by forced expiratory volume in 1 second-forced vital capacity ratio and diffusing capacity of the lung for carbon monoxide percent predicted. The PJL also correlated weakly to CT emphysema severity scoring (r = 0.06; P < 0.002). The area under the receiver operator characteristic curve was 0.652, with maximum accuracy at a width of 1.3 cm. CONCLUSIONS: Our data suggest that despite statistical correlation between the narrowness of the PJL and emphysema, its clinical use is limited.

A 32-year-old man presented with a 2-month history of worsening fever, chills, and cough despite therapy with oral antibiotics. Chest radiographs demonstrated migrating, peripheral upper lobe infiltrates. A CBC count demonstrated significant eosinophilia. At bronchoscopy, eosinophil-rich mucus was seen impacted throughout his bronchi. A transbronchial biopsy confirmed the diagnosis of eosinophilic pneumonia. Symptoms, eosinophilia, and radiographic abnormalities were reversed with cessation of duloxetine. This case report briefly reviews the diagnosis of drug-induced pulmonary infiltrates with eosinophilia (PIEs) and eosinophilic pneumonia. To our knowledge, this is the first reported case of PIEs due to duloxetine.

OBJECTIVE: Recently there has been a significant increase in the use of CT imaging resulting in a significant increase in radiation exposure to the population. Few studies have compared the degree of radiation exposure among the currently available MDCT units. Our objective is to make such a comparison. MATERIALS AND METHODS: Using a Rando anthropomorphic phantom, we placed thermoluminescent dosimeters into the center, anterior, and lateral aspect of the lower chest of the phantom. Standard CT of the chest was performed with the current protocols used at our institution on 4-, 8-, and 16-MDCT GE Healthcare systems. Next, near-identical CT scans of the entire chest were performed on the same CT systems. RESULTS: The 4-detector array showed statistically significantly higher radiation dose compared with the 16-detector array with near-identical technique (p < 0.01). There is a trend toward decreasing radiation dose with the increasing number of detectors using both standard and near-identical technique. An inverse relationship exists between measured radiation dose and the number of detectors. CONCLUSION: We theorize that as the number of detectors increases, there is a decrease in the amount of nonutilized radiation exposure, thus resulting in a lower total radiation dose.

RATIONALE AND OBJECTIVES: To evaluate the potential use of gadolinium (Gd)-based contrast media, especially that of Gadovist, a 1-molar Gd medium, in computed tomography (CT) and compare our findings with standard iodinated contrast media. MATERIAL AND METHODS: Using a live rabbit and an acrylic CT body phantom for comparative CT imaging of Gd- and I-based media. The images were acquired at 80, 100, and 120 kVp, using fixed standard beam filtration. The phantom study used serial dilutions of the Magnevist and Ultravist 300 (2.4-molar I), whereas the animal study used different volumes of Gadovist, Magnevist (0.5 molar Gd), and Ultravist administered intravenously. RESULTS: At 80 kVp for the same injection volumes of Gadovist and Ultravist, the image contrast enhancement of the aorta with Gadovist was 40% lower than that of Ultravist. In the phantom studies, however, for the same kVp settings the CT image contrast was up to fourfold higher for Gd compared with iodine when comparing the same molar concentrations of the two elements in the solutions. CONCLUSION: These results indicate a potential of Gd-based media for clinical CT angiography and provide incentive for further investigation of this subject.

We describe the design and testing of an inductive coupling system used to power an implantable minipump for applications in ambulating rats. A 2 MHz class-E oscillator driver powered a coil transmitter wound around a 33-cm-diameter rat cage. A receiver coil, a filtered rectifier, and a voltage-sensitive switch powered the implant. The implant DC current at the center of the primary coil (5.1 V) exceeded the level required to activate the solenoid valve in the pump. The variations of the implant current in the volume of the primary coil reflected the variations of the estimated coupling coefficient between the two coils. The pump could be activated in-vivo, while accommodating the vertical and horizontal movements of the animal. Advantages of this design include a weight reduction for the implant, an operation independent from a finite power source, and a remote activation/deactivation.