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Spencer B Gay

Publications and source records attributed to Spencer B Gay.

6 recordsLinked to original sources

Clinical experience with radiotracer-guided thoracoscopic biopsy of small, indeterminate lung nodules.

BACKGROUND: Although computed tomography lung-screening programs report a 31% to 51% incidence of subcentimeter pulmonary nodules, 85% are too small to biopsy or interrogate with positron emission spectroscopy scans. We developed a technique using transthoracic percutaneous radiotracer injection with thoracoscopic radioprobe localization and excision for small pulmonary nodules. This report describes our series of the first 46 patients evaluated with this technique. METHODS: Forty-six patients (79% smokers; 52% males; median age, 64 years) were evaluated. Patient selection was based on the surgeon's anticipated difficulty in thoracoscopically locating small nodules because of lesion size or location. Computed tomographic-guided injection of radiotracer solution was made into or adjacent to the nodule the day of surgery. Intraoperative gamma probe localization, followed by thoracoscopic excision of the lesion, was subsequently performed. RESULTS: Median nodule size was 9 mm (range, 3 to 22 mm), and median depth was 5 mm (range, 0 to 50 mm). Forty-four (96%) of the lesions were successfully localized and excised. Median time from injection to surgery was 270 minutes. Failures were the result of inadvertent pleural or chest wall radiotracer placement. Forty-six percent (21 of 46) of the lesions were malignant, of which 71% (15 of 21) were primary lung cancers. Patients with lung cancer underwent lobectomy or segmentectomy. Fourteen of 15 were stage IA, whereas 1 was stage IIIB (6 mm primary with 4 mm intralobar metastasis). Complications were three pneumothoraces at the time of radiotracer injection. CONCLUSIONS: Computed tomography-guided radiotracer localization of small pulmonary nodules combined with thoracoscopic excisional biopsy is feasible and safe. This technique successfully localized and excised the nodule in 96% of cases.

Biopsy↗

A novel technique for localization and excisional biopsy of small or ill-defined pulmonary lesions.

BACKGROUND: The purpose of this study was to develop and evaluate radiotracer-guided localization of small or ill-defined pulmonary nodules for thoracoscopic excisional biopsy. METHODS: This study consisted of two parts: a laboratory study in rats to determine the most suitable radiotracer, and a pilot study in humans to determine the feasibility of radiotracer lung nodule localization. The right lung of 12 rats was injected with a technetium 99m (Tc 99m) based radiotracer solution: 4 each with macroaggregated albumin (MAA), unfiltered sulfur colloid (SC), and pertechnetate (TcO(4)). Serial imaging was performed using a small animal gamma camera for 4 hours following injection. In 13 patients, computed tomographic (CT) guided injection of Tc 99m MAA solution was made into or adjacent to a pulmonary nodule suspicious for primary lung cancer. Gamma probe localization of the nodule was performed during subsequent thoracoscopic surgery. RESULTS: In the animal model, MAA provided more precise localization than SC or TcO(4) and was selected for the human study. In the human series, all 13 patients had successful gamma probe localization of their lesion. There were no radiologic or surgical complications. Seven of 13 nodules were malignant, and five of these nodules were stage IA primary lung carcinomas. CONCLUSIONS: Computed tomographic-guided radiotracer localization of small or ill-defined pulmonary nodules using Tc 99 m MAA before thoracoscopic excisional biopsy is feasible and may make excisional biopsy the preferred management strategy for the management of small pulmonary nodules in patients at high risk for malignancy.

Aged↗

Process involved in reading imaging studies: workflow analysis and implications for workstation development.

Software development for imaging workstations has lagged behind hardware availability. To guide development and to analyze work flow involved in interpretation of cross-sectional imaging studies, we assessed the cognitive and physical processes. We observed the performance and interpretation of body computed tomography (CT scans and recorded the events that occurred during this process. We studied work flow using a bottleneck analysis. Twenty-four ofa total of 54 cases (44%) involved comparing the images with those of prior scans. Forty-seven of 54 scans (87%) were viewed using windows other than soft tissue, or compared with precontrast scans. In 46 cases (85%), the interpretation stopped to return to a previous level for review. Measurement of lesions was performed in 24 of 54 (44%) cases, and in 15 (63%)of these cases, measurements were taken of lesions on old studies for comparison. Interpretation was interrupted in 14 of 54 cases (26%) by referring clinicians desiring consultation. The work flow analysis showed film folder retrieval by the film room to be the bottleneck for interpretation by film. For picture archiving and communication system (PACS) reading,the CT examination itself proved to be the bottleneck. We conclude that workstations for CT interpretation should facilitate movement within scans, comparison with prior examinations, and measuring lesions on these scans. Workstation design should consider means of optimizing time currently not used between interpretation sessions, minimizing interruptions and providing more automated functions currently requiring physician interaction.

Efficiency, Organizational↗

Relative value of analog and digital teaching files.

RATIONALE AND OBJECTIVES: This study was performed to determine if it is financially reasonable for radiology residency programs that create and maintain their own teaching files to switch from analog teaching files (ATFs) to digital teaching files (DTFs). MATERIALS AND METHODS: Radiology residency program directors were surveyed electronically about the monetary value and importance of conventional ATFs and DTFs. The costs for maintaining each type of file were calculated at the authors' institution. RESULTS: Surveys were sent to the program directors of all 197 accredited radiology residencies. Responses were received from 48 (24%). DTFs were scored as more important than ATFs, but the difference was not significant (P = .22). DTFs were rated as less complete (P = .01) but more current (P << .001) than ATFs. DTFs included the American College of Radiology Learning File (85%), in-house productions (77%), and other commercially available products (63%). Thirty percent of respondents had a DTF integrated into a picture archiving and communication system, and 28% reported having a technician dedicated to the teaching file. Program directors ascribed total median dollar values of $250 and $3,000 per year to their ATFs and DTFs, respectively. The annual costs at the authors' institution were much higher than these ascribed values: $44,720 ($91 per case) for maintaining a DTF produced in house and $24,601 ($50 per case) for maintaining an ATF, excluding physician time. CONCLUSION: Program directors are more willing to pay for a DTF than an ATF. For both, the costs of maintenance are great and the relative monetary value is low.

Analog-Digital Conversion↗