Gary Gelfand

Segmentation of Lung Lobes in High-Resolution Isotropic CT Images

Modern multislice computed tomography (CT) scanners produce isotropic CT images with a thickness of 0.6 mm. These CT images offer detailed information of lung cavities, which could be used for better surgical planning of treating lung cancer. The major challenge for developing a surgical planning system is the automatic segmentation of lung lobes by identifying the lobar fissures. This paper presents a lobe segmentation algorithm that uses a two-stage approach: (1) adaptive fissure sweeping to find fissure regions and (2) wavelet transform to identify the fissure locations and curvatures within these regions. Tested on isotropic CT image stacks from nine anonymous patients with pathological lungs, the algorithm yielded an accuracy of 76.7%-94.8% with strict evaluation criteria. In comparison, surgeons obtain an accuracy of 80% for localizing the fissure regions in clinical CT images with a thickness of 2.5-7.0 mm. As well, this paper describes a procedure for visualizing lung lobes in three dimensions using software-amira-and the segmentation algorithm. The procedure, including the segmentation, needed about 5 min for each patient. These results provide promising potential for developing an automatic algorithm to segment lung lobes for surgical planning of treating lung cancer.

Functional results and quality of life after tracheal resection for locally invasive thyroid cancer.

BACKGROUND Local invasion of the upper aerodigestive tract by thyroid cancer, although uncommon, is a serious cause of morbidity and mortality. The impact of aerodigestive tract resection on the functional status and quality of life of the patient has not previously been investigated. METHODS Patients with locally invasive thyroid cancer were included in a prospective surgical protocol. Swallowing function was assessed with barium swallow at 7 days and 1 month postoperatively. Postoperative quality of life (QOL) was measured using a validated head and neck QOL instrument. RESULTS Seven patients underwent airway resection for locally invasive recurrent thyroid cancer in the period 1999 to 2001. At 1 week postoperative 3 of 7 (43%) had no evidence of aspiration on barium swallow. At 4 weeks 6 of 7 (86%) had no aspiration. Postoperative QOL scores in the domains of eating function (85.2) and emotional status (78.6) were significantly better than those of a comparison group undergoing treatment for cancers of the oropharynx, P = 0.012 and P = 0.0077, respectively. CONCLUSIONS Tracheal resection for locally invasive thyroid cancer is associated with a return to full dietary intake within 4 weeks of surgery in most cases. Function and QOL after this type of surgery are acceptable.

Thoracic Surgery Training in Canada According to the Residents: The Thoracic Surgery Resident Survey, of the Canadian Thoracic Manpower and Education Study (T-Med)

OBJECTIVE The resident component of the Canadian Thoracic Manpower and Education Study (T-MED) was conducted to understand the basic demographic of Canadian thoracic surgery residents, the factors influencing their selection of training programs, current work conditions, training and competencies, and opinions in regard to the manpower needs for the specialty. DESIGN A modified Delphi process was used to develop a survey applicable to thoracic surgery residents. In May and June 2009, residents completed the voluntary anonymous Internet-based survey. All Canadian residents participated in the survey, providing a 100% response rate. RESULTS Most respondents were male (11/12), and the average age was 34 years old with an anticipated debt greater than

Idiopathic subglottic stenosis: a familial predisposition.

50,000 on graduation. All residents worked more than 70 hours per week, with most doing 1 : 3 or 1 : 4 on-call. Two-thirds of respondents reported being satisfied or very satisfied with their training program. Rates of anticipated competence in performing various thoracic surgeries on graduation differed between residents and program directors. Two-thirds (8/12) of residents planned to practice thoracic surgery exclusively, and hoped to practice in an academic setting. Most residents (10/12) agreed or strongly agreed that not enough jobs are available in Canada for graduating trainees and that the number of residency positions should reflect the predicted availability of jobs. CONCLUSIONS This study has provided detailed information on thoracic surgery resident demographics and training programs. Most thoracic surgery residents are satisfied with their current training program but have concerns about their job prospects on graduation, and they believe that the number of training positions should reflect potential job opportunities. This survey represents the first attempt to characterize the current state of thoracic surgery training in Canada from the residents perspective and may help in directing educational and manpower planning.

Bronchoscopic Removal of a Large Intracavitary Pulmonary Aspergilloma

Idiopathic subglottic stenosis is a narrowing of the trachea at the level of the cricoid cartilage of unknown etiology. It is a rare condition for which the real incidence has never been established owing to the difficulty of making the diagnosis. Although there is a female preponderance, no familial cases have been reported in the literature. We describe two pairs of sisters as well as a mother and daughter presenting with idiopathic subglottic stenosis. All known causes of tracheal stenosis were excluded, including prolonged intubation, surgery, autoimmune and inflammatory disorders, infection and gastroesophageal reflux disease. These are the first cases reported in the literature that suggest a genetic predisposition for idiopathic subglottic stenosis.

Can preoperative computed tomography of the chest predict completeness of the major pulmonary fissure at surgery

Pulmonary aspergilloma is a chronic fungal infection that has a high mortality when hemoptysis occurs. Surgery is the treatment of choice, but patients often have severe physiologic impairment putting them at risk for significant surgical morbidity and mortality. We present the case of a 63-year-old woman with a large aspergilloma, unfit for surgery due to medical reasons. The aspergilloma was enlarging, with progression of the patients symptoms of anorexia, cough, chest discomfort, and hemoptysis. Bronchoscopy revealed an airway leading into a cavity with a large fungal ball. Biopsy confirmed Aspergillus fumigatus. Using flexible and rigid bronchoscopy, the aspergilloma was mechanically removed. Eighteen months later the patient reported no hemoptysis, reduced pain and cough, significant weight gain, and improved appetite, with no recurrence of the aspergilloma on repeat imaging. To our knowledge, this is the first reported case of bronchoscopic removal of a large cavitary aspergilloma. This important new treatment modality provides a viable alternative therapy for this potentially life-threatening problem.

The effects of antireflux surgery on asthmatics with gastroesophageal reflux.

BACKGROUND An incomplete major pulmonary fissure can make anatomic lung resection technically more difficult and may increase the risk of complications, such as prolonged postoperative air leak. The objective of this study was to determine if preoperative computed tomography (CT) of the chest could accurately predict the completeness of the major pulmonary fissure observed at the time of surgery. METHODS From October 2008 to June 2009, patients at a single university institution were enrolled if they underwent surgery for a pulmonary nodule, mass or known cancer. At the time of surgery, completeness of the major pulmonary fissure was graded 1 if pulmonary lobes were entirely separate, 2 if the visceral cleft was complete with an exposed pulmonary artery at the base with some parenchyma fusion, 3 if the visceral cleft was only evident for part of the fissure without a visible pulmonary artery and 4 if the fissure was absent. The preoperative CT scan of each patient was graded by a single, blinded chest radiologist using the same scale. We used the Pearson χ2 test with 2-tailed significance to test the independence of the operative and radiologic grading. RESULTS In 48% (29 of 61) of patients, the radiologic and operative grading were the same. Of those graded differently, 94% (30 of 32) were within 1 grade. Despite this agreement, we observed no statistically significant correlation between the operative and radiologic grading (p = 0.24). CONCLUSION The major fissure can often be well-visualized on a preoperative CT scan, but preoperative CT cannot accurately predict the completeness of the major pulmonary fissure discovered at surgery.