Biomedical subjects

Heinrich D Becker

Publications and source records attributed to Heinrich D Becker.

10 recordsLinked to original sources

PubMed2006

Electromagnetically navigated brachytherapy as a new treatment option for peripheral pulmonary tumors.

PURPOSE: This technical note describes the principles of navigated brachytherapy for treatment of peripheral non-small cell lung cancer (NSCLC). MATERIAL AND METHODS: In a prospective feasibility trial a first patient with medically inoperable NSCLC in the right upper lobe was treated with external-beam radiotherapy (50 Gy) and navigated endoluminal brachytherapy (15 Gy). Navigated bronchoscopy was performed with an electromagnetic navigation system for localization of a microsensor mounted on the tip of a dedicated catheter placed within the working channel of a bronchoscope. The probe can be actively guided by a steering mechanism to targeted lesions in the periphery of the lung. After successful localization of the NSCLC, endobronchial ultrasound (EBUS) was performed to confirm the exact position in the center of the lesion. A 6-F brachytherapy catheter was placed within the tumor. Primary 3-D-planned brachytherapy was performed on chest CTs acquired with the inserted catheter. High-dose-rate brachytherapy (370 GBq iridium-192) was applied as a boost three times a week (single dose 5 Gy) and provided highly conformal irradiations of the NSCLC including the draining bronchovascular bundle. RESULTS: The brachytherapy catheter was tolerated well during treatment (5 days) and alimentation was possible without any problems. Repeated CTs showed stable positioning of the catheter. During follow-up (12 months), endoluminal ultrasound and CT demonstrated a partial remission while histology showed a complete remission of the tumor. CONCLUSION: Navigated brachytherapy for peripheral pulmonary tumors not amenable to conventional bronchoscopy is feasible.

Brachytherapy↗

PubMed2006

Effect of routine clopidogrel use on bleeding complications after transbronchial biopsy in humans.

STUDY OBJECTIVES: Clopidogrel is often prescribed for primary or secondary prevention of cardiovascular disease and has been associated with unwanted bleeding events. After having shown that transbronchial biopsy can safely be performed in pigs receiving clopidogrel, we sought to determine whether routine clopidogrel use increases the risk of bleeding after transbronchial lung biopsy in humans. DESIGN: Prospective cohort study. PATIENTS AND INTERVENTIONS: Data were collected on 604 patients without underlying coagulation problems who underwent transbronchial lung biopsy over 13 months. Clopidogrel was not discontinued before biopsy in patients who were using it. Transbronchial biopsies were performed, and the incidence of bleeding and other complications among patients receiving clopidogrel was compared with that of other patients. RESULTS: The study was stopped early because the bleeding rate in the clopidogrel-only group (n = 18) was excessive (89% [16 of 18 patients] vs 3.4% [20 of 574 control subjects; p > 0.001] and also in the group receiving clopidogrel and aspirin (100% [12 of 12 patients] vs 3.4% among control subjects [p > 0.001]. Bleeding rates were significantly higher in the clopidogrel group for each degree of bleeding severity: mild (27% vs 1.5%), moderate (34% vs 1.5%), and severe (27% vs 0.3%; p > 0.001 for all comparisons). All 12 patients receiving both aspirin and clopidogrel had bleeding: moderate in 6 patients and severe in 6 patients. All bleeding was controlled by endoscopic means. There were no fatalities or need for blood transfusions in the patients enrolled in the trial. CONCLUSIONS: Clopidogrel use greatly increases the risk of bleeding after transbronchial lung biopsy in humans and therefore should be discontinued before bronchoscopy with biopsies. Aspirin exacerbates the effect of clopidogrel on bleeding.

Adult↗

PubMed2006

Real-time electromagnetic navigation bronchoscopy to peripheral lung lesions using overlaid CT images: the first human study.

STUDY OBJECTIVES: To characterize the feasibility, accuracy, and safety of the superDimension/Bronchus system (SDBS) [superDimension, Ltd; Hertzliya, Israel] in navigating to previously unreachable peripheral lung lesions and obtaining biopsy specimens. DESIGN: Open-label, prospective, controlled clinical study. SETTING: Pulmonary institute of a university-affiliated municipal hospital. PATIENTS: Thirteen adult candidates for nonemergency bronchoscopy who gave informed consent to participate. INTERVENTIONS: The patients underwent flexible bronchoscopy using the SDBS, which is based on real-time CT-guided electromagnetic navigation and is capable of reaching peripheral lung masses beyond the reach of the bronchoscope. A position sensor was used to navigate to and sample the various target lesions for biopsy. MEASUREMENTS AND RESULTS: Three-dimensional chest CT was followed by SDBS methodology for marking anatomic landmarks and the target lesion on a virtual bronchoscopy screen and for sampling the lesion. The SDBS assisted in obtaining positive biopsy diagnoses in 9 of 13 cases (69%), with an average navigation accuracy of 5.7 mm. There were no SDBS-related adverse events. CONCLUSIONS: The SDBS is safe and effective in navigating to peripheral lung lesions located beyond the optic limits of a standard flexible bronchoscope.

Adult↗

PubMed2005

Transbronchial versus transesophageal ultrasound-guided aspiration of enlarged mediastinal lymph nodes.

RATIONALE: Transesophageal and transbronchial, ultrasound-guided, fine-needle aspiration of enlarged mediastinal lymph nodes have become popular, but have never been compared directly. OBJECTIVES: To compare the relative diagnostic yield and ability of the transesophageal and transbronchial approaches to reach abnormal mediastinal lymph nodes. METHODS: A total of 160 patients with enlarged lymph nodes in one of eight mediastinal lymph node stations underwent transbronchial and transesophageal biopsies in a crossover design. Each of the eight stations was allocated 20 patients. Two needle punctures were done with each approach. MEASUREMENTS: Percentage of successful biopsies, percentage of patients diagnosed, and biopsy time were measured from when the lymph node was identified with ultrasound. MAIN RESULTS: Among the 106 men and 54 women (mean age 53.2 years), transbronchial aspiration was successful in 85%, and transesophageal aspiration was successful in 78% (p = 0.2). For each station, the number of positive samples for the transbronchial/transesophageal approaches was: 2R: 19/13; 2L: 16/19; 3: 17/15; 4R: 19/12; 4L: 17/20; 7: 19/20; 10R: 18/9; and 10L: 17/18. Combining both approaches produced successful biopsies in 97% and diagnoses in 94% of patients. Mean biopsy times were 3.2 minutes for the transbronchial approach and 4.1 minutes for the transesophageal approach. The transbronchial approach was superior in nodes 2R, 4R, and 10R. No complications were encountered. CONCLUSIONS: In experienced hands, enlarged mediastinal lymph nodes may be aspirated with either the transbronchial or transesophageal approach. These nonsurgical approaches have similar diagnostic yields, although the transbronchial approach is superior for right-sided lymph nodes. Combining both approaches provides results similar those of mediastinoscopy.

Adult↗

PubMed2005

Effect of clopidogrel with and without aspirin on bleeding following transbronchial lung biopsy.

BACKGROUND: Clopidogrel, a potent inhibitor of platelet aggregation, is being commonly prescribed in the elderly population due to its benefits in patients with atherosclerotic diseases. It is currently unknown whether clopidogrel increases the risk of bleeding during invasive pulmonary procedures. METHODS: Pigs of the Yorkshire species were randomized to one of the following two arms: clopidogrel (75 mg/d) alone; or clopidogrel plus aspirin (75 mg/d and 325 mg/d, respectively). The animals underwent flexible bronchoscopy with transbronchial lung biopsies under fluoroscopic guidance at baseline and after 1 week of daily oral intake of their assigned drugs. The main outcome of the study was the quantity of blood collected through the bronchoscope following transbronchial lung biopsy (TBLB). RESULTS: Sixteen animals were enrolled in the study, with 8 animals randomized to each arm. No statistically significant difference was found in the average quantity of blood resulting from transbronchial lung biopsies between procedures performed at baseline and those performed after animals received either clopidogrel (mean [+/- SD] dose, 1.41 +/- 1.14 mL) or clopidogrel plus aspirin (mean dose, 1.75 +/- 1.28 mL; p = 0.42). CONCLUSIONS: Clopidogrel, with or without aspirin, does not increase bleeding complications after TBLB in healthy pigs.

Animals↗

PubMed2005

Endoscopic drainage of lung abscesses: technique and outcome.

BACKGROUND: Lung abscesses commonly respond well to antibiotic therapy. In patients in whom conventional therapy fails, either percutaneous catheter drainage or surgical resection are usually considered, but are frequently problematic. This study describes our experience with endoscopic lung abscess drainage in patients in whom antibiotic therapy fails. METHODS: Patients in whom antibiotic therapy for lung abscess (enlarging cavity or lack of improvement of clinical status) was unsuccessful were considered candidates if an airway connection to the cavity was present. Treatment decisions were made in a multidisciplinary chest conference. Pigtail catheters were placed via a guidewire approach into the cavities. The abscesses were flushed twice daily with gentamycin solution. If fungal infection was suspected, once-daily amphotericin B was added to the regimen. RESULTS: Forty-two patients, from January 2000 to May 2002 (17 woman and 25 men) were included in this study (mean age, 48.9 years). Catheter placement was successful in 38 patients and led to successful therapy after a mean of 6.2 days of treatment (range, 3 to 21 days). Two patients required transient ventilation after catheter placement; there were no other complications. CONCLUSIONS: Endoscopic lung abscess drainage in selected patients in whom antibiotic therapy fails is feasible and successful in experienced hands. This treatment represents an additional option for the chest physician other than percutaneous catheter drainage or surgical resection.

Adult↗

PubMed2004

Central airway obstruction.

Central airway obstruction is a problem facing all medical and surgical subspecialists caring for patients with chest diseases. The incidence of this disorder appears to be rising because of the epidemic of lung cancer; however, benign causes of central airway obstruction are being seen more frequently as well. The morbidity is significant and if left untreated, death from suffocation is a frequent outcome. Management of these patients is difficult, but therapeutic and diagnostic tools are now available that are beneficial to most patients and almost all airway obstruction can be relieved expeditiously. This review examines current approaches in the workup and treatment of patients suffering from airway impairment. Although large, randomized, comparative studies are not available, data show significant improvement in patient outcomes and quality of life with treatment of central airway obstruction. Clearly, more studies assessing the relative utility of specific airway interventions and their impact on morbidity and mortality are needed. Currently, the most comprehensive approach can be offered at centers with expertise in the management of complex airway disorders and availability of all endoscopic and surgical options.

Airway Obstruction↗

PubMed2004

Conventional vs endobronchial ultrasound-guided transbronchial needle aspiration: a randomized trial.

STUDY OBJECTIVE: Our group performed a randomized trial to assess whether the addition of endobronchial ultrasound (EBUS) guidance will lead to better results than standard transbronchial needle aspiration (TBNS). EBUS guidance seems to be beneficial in increasing the yield of TBNA but has not been proven to be superior to conventional procedures in a randomized trial. METHODS: Consecutive patients who were referred for TBNA were randomized to an EBUS-guided and a conventional TBNA arm. Patients with subcarinal lymph nodes were randomized and analyzed separately (group A) from all other stations (group B). A positive result was defined as either lymphocytes or a specific abnormality on cytology. RESULTS: Two hundred patients were examined (100 patients each in groups A and B). Half of the patients underwent EBUS-guided TBNA rather than conventional TBNA. In group A, the yield of conventional TBNA was 74% compared to 86% in the EBUS group (difference not significant). In group B, the overall yields were 58% and 84%, respectively. This difference was statistically highly significant (p < 0.001). The average number of passes was four. CONCLUSION: EBUS guidance significantly increases the yield of TBNA in all stations except in the subcarinal region. It should be considered to be a routine adjunct to TBNA. On-site cytology may be unnecessary, and the number of necessary needle passes required is low.

Biopsy, Needle↗

PubMed2003

Ultrasound-guided transbronchial needle aspiration: an experience in 242 patients.

STUDY OBJECTIVES: Conventional transbronchial needle aspiration (TBNA) is a valuable procedure but remains underutilized. Recently, imaging guidance such as CT fluoroscopy has created considerable interest. As CT fluoroscopy is cumbersome and exposes patients and staff to radiation, we have examined the feasibility of endobronchial ultrasound (EBUS) in providing imaging support for TBNA. DESIGN: Prospective consecutive patient enrollment. SETTING: University-related tertiary referral centers for pulmonary diseases. RESULTS: From January 1999 to January 2000, 242 consecutive patients were entered into this prospective study (82 women and 160 men; mean age, 60.0 years). Indications for TBNA were diagnosis of enlarged lymph nodes and cancer staging. The average lymph node size was 1.7 cm (SD, 0.47; range, 0.8 to 4.3 cm). Target lymph nodes were visualized with EBUS, followed by TBNA in standard fashion. All targets could be visualized with EBUS. In 207 patients, the lymph nodes were successfully sampled (86%). This was independent of lymph node size and location. A firm diagnosis or cancer stage could be obtained in 172 patients (72%). There were no complications associated with the use of EBUS. CONCLUSION: EBUS is simply performed and if used for TBNA guidance affords an excellent yield independent of lymph node location. Randomized trials comparing standard TBNA and imaging-guided TBNA by CT fluoroscopy and EBUS are indicated.

Adult↗

PubMedDate not supplied

Electromagnetic navigation during flexible bronchoscopy.

BACKGROUND: Flexible bronchoscopy is routinely utilized in the diagnosis and treatment of various lung diseases. Nondiagnostic bronchoscopy leads to more invasive interventions, such as transthoracic needle aspiration, mediastinoscopy or even thoracotomy. Electromagnetic navigation is a novel technology that facilitates approaching peripheral lung lesions, which are difficult to sample by conventional means. The navigation system involves creating an electromagnetic field around the chest and localizing an endoscopic tool using a microsensor overlaid upon previously acquired CT images. OBJECTIVES: To determine the practicality, accuracy and safety of real-time electromagnetic navigation, coupled with previously acquired 3D CT images, in locating artificially created peripheral lung lesions in a swine model. METHODS: Peripheral lung lesions were created in four swine models by insertion of a metal tube (1 x 10 mm) via a transthoracic approach. An electromagnetic field was created by placing the animal on an electromagnetic location board. A position sensor incorporated into the distal tip of a dedicated tool was used to navigate to the various target lesions. Information gathered in real time during bronchoscopy was presented on a monitor simultaneously by displaying previously acquired CT images. Upon reaching the target lesion, biopsies were performed and the functionality and safety of the superDimension/Bronchus System was observed and documented. RESULTS: The registration accuracy expressed by the fiducial target registration error, expressing both the registration quality and the stability of fiducial (registration) points, was 4.5 mm on average. No adverse effects, such as pneumothorax or internal bleeding, were encountered in any of the animals in this study. CONCLUSIONS: Real-time electromagnetic positioning technology coupled with previously acquired CT images is an accurate technology added to standard bronchoscopy to assist in reaching peripheral lung lesions and performing biopsies.

Animals↗