Valery Scharf

Primary spontaneous pneumothorax (PSP) is defined as the presence of air within the pleural space without an obvious precipitating factor. This disease presents as a life-threatening emergency causing shortness of breath, exercise intolerance, and possible collapse or sudden death, affecting an average of 13 dogs per year at our institution. Although the overall prevalence is fairly low, PSP is of great importance due to the impact on the individual dog. Treatment of PSP in dogs remains challenging. Current standard of care dictates full thoracic exploration via an invasive median sternotomy followed by resection of affected lung lobes. Video-assisted thoracoscopic surgery (VATS) is preferred over open thoracotomy in human medicine as it is associated with lower morbidity and reduced post-operative pain, making it a desirable alternative to the current standard in veterinary medicine. Historical limitations in correctly identifying pulmonary bullae associated with spontaneous pneumothorax in dogs has limited the usefulness of VATS. Investigators have recently established the efficacy of using a variable angle endoscope to thoracoscopically identify pulmonary bullae in dogs. Additionally, autologous blood injection has been demonstrated in people to seal leaking lung tissue. Thus, this pilot study aims to prospectively evaluate the efficacy of minimally invasive autologous blood injection to treat primary spontaneous pneumothorax in dogs. We hypothesize that thoracoscopic autologous blood injection will effectively seal pulmonary bullae and blebs in dogs with primary spontaneous pneumothorax, facilitating minimally invasive treatment of this disease in dogs with potential extension to treating primary spontaneous pneumothorax in people.

Hypothesis: We hypothesize that ICG can be repeatedly administered without persistence of parathyroid gland fluorescence and without a cumulative dose effect, and that fluorescence of the parathyroid glands will subside within 10 minutes of initial observation of fluorescence. We also hypothesize that both external and internal parathyroid glands will fluoresce and that 0.015 mg/kg administered once intravenously will provide optimal parathyroid gland fluorescence. Specific Aims: The objective of the pilot study is to evaluate for a potential cumulative dose effect on fluorescence of parathyroid glands with repeated ICG administration and to measure the time to peak fluorescence and subsidence of fluorescence following repeated ICG dosage. The objective of the subsequent dose optimization study is to determine the optimal intravenous ICG dosage and timing to detect normal parathyroid glands using NIRF imaging in dogs. A secondary objective is to assess the degree of fluorescence and feasibility of visualization of both external and internal parathyroid glands using ICG NIRF to aid in intraoperative identification.

Primary spontaneous pneumothorax is defined as the presence of air within the pleural space without an obvious precipitating factor. Large breed, deep-chested dogs, particularly Huskies and hunting breeds, are most commonly affected. Development of this disease is associated with the presence of pulmonary bullae. The diagnosis and localization of pulmonary bullae in dogs remains challenging; thus the objective of this study is to evaluate the feasibility of a minimally invasive diagnostic procedure (variable-angle thoracoscopy) for identification and localization of pulmonary bullae.

The objective of this study is to describe and assess a novel intraoperative NIRF imaging technique using aerosolized ICG to visualize healthy pulmonary parenchyma thoracoscopically, and to evaluate clinical feasibility of this technique in a canine model. A secondary objective is to determine the optimal dosage and timing of administration and to assess acute and delayed effects of inhalational ICG on postoperative pulmonary function and tissue histology.

The objectives of this study are to 1) evaluate a novel minimally invasive approach for attenuation of PA shunts in dogs via thoracoscopic placement of ARCs, and to 2) prospectively evaluate the efficacy of thoracoscopically placed ARCs to attenuate PA shunts based on clinical assessment, biochemical values, and diagnostic imaging results.