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E vanSonnenberg

Publications and source records attributed to E vanSonnenberg.

At least 19 recordsLinked to original sources
PubMed2001

Percutaneous abscess drainage: update.

During the approximately 20 years that percutaneous abscess drainage (PAD) has been an extant procedure and as the millennium begins, PAD has become, by consensus, the treatment of choice for abscesses. Indications for PAD continue to expand, and currently almost all abscesses are considered amenable. On occasion, PAD is an adjunctive procedure that provides a beneficial temporizing effect for the surgeon who eventually must operate for a coexisting problem such as a bowel leak. Simple unilocular abscesses are cured almost uniformly by PAD; more complicated abscesses, such as those with enteric fistulas (e.g., diverticular abscess) or pancreatic abscesses, have cure rates ranging from 65% to 90%. Various catheters and insertion techniques have proven effective. Ultrasonography, computed tomography, and fluoroscopy are the staple modalities that guide PAD. PAD is the prototype interventional radiology procedure, providing detection of the abscess by imaging, needling for diagnosis, and catheterization for therapy.

Abdominal Abscess↗
PubMed2000

MR imaging-guided percutaneous cryotherapy of liver tumors: initial experience.

PURPOSE: To describe the cryoablation of liver tumors by using a percutaneous approach and intraprocedural magnetic resonance (MR) imaging monitoring and to assess the feasibility and safety of the procedure. MATERIALS AND METHODS: Fifteen hepatic tumors (mean diameter, 2.9 cm) in 12 patients were treated (18 total cryoablations). Fourteen were metastases and one was a hemangioma; all were proved at biopsy. By using a 0.5-T open MR imaging system, cryoneedles were placed and lesions ablated by using real-time monitoring. Clinical signs and symptoms were assessed and laboratory tests performed. Intraprocedural depictions of iceballs were compared with contrast material-enhanced MR imaging-based estimates of cryonecrosis that were obtained 24 hours after cryoablation. RESULTS: MR imaging-guided percutaneous cryotherapy resulted in no serious complications and no clinically important changes in serum liver enzymes or creatinine or myoglobin levels. Intraprocedural MR imaging demonstrated iceballs as sharply marginated regions of signal loss that expanded and engulfed tumors. The maximal iceball size was 4.9 x 2.2 x 2.2 cm with the use of one cryoneedle and 6.0 x 5.6 x 4.9 cm with three cryoneedles. Intraprocedural iceball depictions correlated well with postprocedural cryonecrosis estimates. CONCLUSION: MR imaging-guided percutaneous cryotherapy of liver tumors is feasible and safe. MR imaging can be used to estimate cryotherapy effects and guide therapy intraprocedurally.

Adult↗
PubMed2000

Continuous speech recognition in MR imaging reporting: advantages, disadvantages, and impact.

OBJECTIVE: Our objective was to describe our experience with a commercially available continuous speech recognition system, highlighting the advantages, disadvantages, and costs compared with those of conventional transcription for MR imaging reports. MATERIALS AND METHODS: Data from 5072 reports generated in our MR imaging section during a 9-month period after the implementation of a commercial continuous speech recognition system were compared with 4552 reports produced during the same period 1 year earlier. Information pertaining to the use of continuous speech recognition, report turnaround time, word recognition rate, report appearance, and equipment costs was collected. RESULTS: After its system installation, continuous speech recognition was used to dictate 81.8% of all reports. The mean report turnaround time decreased from 87.8 to 43.6 hr, and report availability at 24 hr increased from 10.5% to 62.5%. The system was found to have an average word recognition accuracy of 92.7% for spontaneous dictation. Mean report length declined from 95 to 60 words, with an increase in spacing errors from 0.3 to 8.0 per 1000 words and a decrease in spelling errors from 3.0 to 0.8 per 1000 words. Initial hardware and software costs were approximately $10,000, compared with a yearly cost of $12,000 for human transcription. CONCLUSION: Although the technology is still evolving and was evaluated in its earliest implementation stages, continuous speech recognition nonetheless markedly improved report turnaround time and proved cost-effective.

Cost-Benefit Analysis↗
PubMed1999

Persistent pancreatocutaneous fistula after percutaneous drainage of pancreatic fluid collections: role of cause and severity of pancreatitis.

PURPOSE: To assess the relationship between the cause and severity of pancreatitis and the development of persistent pancreatocutaneous fistula (PPCF) after percutaneous drainage of pancreatic fluid collections. MATERIALS AND METHODS: Sixty patients (44 male, 16 female; age range, 10-74 years) were included in the study. The cause of pancreatitis was postoperative in 29 patients, alcoholism in 20 patients, biliary in six patients, hyperlipidemia in two patients, unknown in two patients, and trauma in one patient. Patients requiring intensive care unit treatment for their condition at the time of drainage were considered to have severe pancreatitis. Thirty-seven patients had mild pancreatitis, and 23 had severe pancreatitis. PPCF was defined as catheter drainage of pancreatic fluid of more than 10 mL/d for more than 4 weeks after catheter placement. RESULTS: PPCF developed in 27 of the 60 patients. It occurred in five of the six patients with biliary pancreatitis, 10 of the 20 with alcohol-related pancreatitis, and 10 of the 29 with postoperative pancreatitis (P > .2). The prevalence of PPCF was higher in patients with severe pancreatitis (n = 16 [70%]) than in those with mild pancreatitis (n = 11 [30%]). This difference was statistically significant (P < .002). CONCLUSION: Development of PPCF correlated with severity of pancreatitis, regardless of the cause of pancreatitis.

Adolescent↗
PubMed1999

CT-guided catheter drainage of loculated thoracic air collections in mechanically ventilated patients with acute respiratory distress syndrome.

OBJECTIVE: We report our experience with CT-guided percutaneous catheter drainage of loculated thoracic air collections in mechanically ventilated patients with acute lung injury or acute respiratory distress syndrome. MATERIALS AND METHODS: Nine critically ill patients had 17 air collections (13 pneumothoraces, three pneumatoceles, one tension pneumomediastinum) that either developed despite the presence of standard surgical chest tubes or were in loculated sites that were difficult to access. All nine patients were ventilated mechanically for a clinical diagnosis of acute respiratory distress syndrome. Catheter size ranged from 7- to 28-French. Response was measured by imaging follow-up, ventilatory parameters, and clinical outcome. RESULTS: On follow-up imaging studies, all 17 air collections were shown to have been evacuated successfully. Catheters remained in place for a mean of 11 days (range, 4-28 days). No major complications occurred. Sixteen air collections were treated successfully with CT-guided catheter placement alone; the remaining air collection, a pneumothorax, was treated with subsequent placement of a chest tube by the surgeon at the patient's bedside. No surgery was undertaken for the air collections. Improvement in gas exchange was documented by increase in the hypoxemia ratio (arterial oxygen pressure divided by the inspired fraction of oxygen) in seven of 12 drainages; the other drainages were accompanied either by no improvement or by deterioration. Eight (89%) of the nine patients eventually were extubated and discharged from the hospital. The ninth patient died. CONCLUSION: CT-guided percutaneous catheter drainage provided effective treatment for loculated thoracic air collections and obviated surgical intervention in these critically ill, high-surgical-risk patients.

Adult↗
PubMed1998

Percutaneous drainage of thoracic collections.

Various infected and noninfected thoracic fluid collections may be diagnosed and treated by interventional radiologic techniques. The core procedure of ultrasound-guided thoracentesis has been expanded to allow catheter drainage of empyema, bronchopleural fistula, abscesses in the lung, mediastinum, pericardium, and infected tumors. Tailored use of guidance methods permits effective evacuation of most of these abscesses and noninfected collections. This paper details the authors' approach to each of these entities while highlighting the results and expected pitfalls of these techniques.

Abscess↗
PubMed1998

Radiologic management of hepatolithiasis.

We describe the diagnostic workup and therapeutic management of patients with hepatolithiasis from the viewpoint of the interventional radiologist. The diagnosis is best established by direct cholangiography such as percutaneous transhepatic cholangiography or endoscopic retrograde cholangiography. We consider percutaneous transhepatic stone removal a highly successful, minimally invasive, and safe procedure. Access can be gained to the biliary system in almost 100% of patients and complete stone clearance through percutaneous techniques, including stone fragmentation, removal of stones and fragments by baskets, and dilatation of underlying strictures in more than 90%. The role of these radiologic techniques is discussed vis-à-vis endoscopic and surgical alternatives.

Bile Ducts, Intrahepatic↗
PubMed1997

Airway simulation to guide stent placement for tracheobronchial obstruction in lung cancer.

BACKGROUND: To effectively palliate large airway obstruction in advanced unresectable lung cancer (stage IIIB or IV), we developed an airway imaging technique to guide selective endobronchial metallic stent placement. METHODS: Fourteen consecutive patients with severe dyspnea (American Thoracic Society grade 4) had a combination of fiberoptic bronchoscopy, chest roentgenography, computed tomographic scanning, helical computed tomography with three-dimensional reconstruction, and intraluminal bronchography with selective bronchial guidewire placement under fluoroscopy to visually reconstruct and simulate the abnormal airway before and during stent placement. Wallstent or Gianturco intraluminal stents were used alone or in combination (up to five stents) to establish patency of the distal trachea and the major bronchi. RESULTS: All 14 patients had successful deployment with initial relief of airway stenosis (>75% predicted diameter). No procedural complications were noted. However, technical problems included stent foreshortening and imprecision of placement, misinterpretation of bronchography (mucous versus tumor), and airway maintenance during manipulation. Length of stay attributable to the procedure averaged 4 days. Stent placement initially improved the dyspnea score in 7 of 14 patients. Five of 14 died in less than 1 month, with the remainder alive at up to 8 months' follow-up. Of those surviving more than 1 month, the Karnofsky score improved in 4 and was unchanged in 5, with 2 dependent (Karnofsky score <50), 3 functional (Karnofsky score, 50 to 70), and 4 active (Karnofsky score >70). CONCLUSIONS: A protocol combining helical computed tomography with three-dimensional reconstruction, bronchography, and bronchoscopy allows accurate assessment of malignant airway obstruction to facilitate intralumenal stent placement for relief of stenosis. Patient selection to favor effective palliation and cost effectiveness has yet to be defined.

Adult↗
PubMed1997

Interventional radiology of the biliary tract.

Interventional radiology provides a range of management options applicable to a broad spectrum of patients with biliary tract disorders. This review highlights the importance of these procedures, and illustrates their safety and effectiveness. Percutaneous transcatheter decompression has a well-established role in the management of patients with benign and malignant biliary obstruction. The advent of metallic stents has greatly increased the value of these techniques. Patients with biliary tract calculi can be successfully treated with a variety of percutaneous techniques, obviating surgery and providing a useful alternative to endoscopic methods. Finally, percutaneous cholecystostomy has evolved as a valuable adjunct in the treatment of calculous cholecystitis, as well as providing the definitive cure for many patients with acalculous cholecystitis.

Biliary Tract Diseases↗
PubMed1997

Percutaneous radiologic drainage of pancreatic abscesses.

OBJECTIVE: The purpose of our study was to review and report the patient selection, techniques, and results of percutaneous drainage of pancreatic abscesses by retrospective review. MATERIALS AND METHODS: Fifty-nine patients (46 men and 13 women) with a mean age of 44 years old had 80 pancreatic abscesses that were drained percutaneously under radiologic guidance (CT, n = 77; sonography, n = 2; and fluoroscopy, n = 1). Abscesses had a wide spectrum of causes, with alcoholic pancreatitis being most common, trauma second most common, and gallstones third. Ten patients had undergone surgery for pancreatic necrosis or abscess. Patients with pancreatic pseudocysts, necrosis, or acute fluid collections were excluded from this study. RESULTS: Of the 59 patients, 51 (86%) were cured with percutaneous drainage and antibiotic therapy. Of the patients who were not cured with percutaneous drainage, seven required surgery and one underwent repeat percutaneous drainage. In the 59 patients, complications included non-life-threatening bleeding in three patients. Ten of 59 patients (17%) had fistulas that spontaneously formed into the gastrointestinal tract. The duration of catheterization ranged from 4 to 119 days, with a mean duration of 33 days. The rate of mortality at 30 days after completion of percutaneous drainage was 8% (5 of 59). CONCLUSION: Percutaneous drainage was an effective therapy for this defined group of patients with pancreatic abscesses. Factors leading to the relatively high success rate described in this study likely included selection of patients; catheters of adequate size, number, and location; careful follow-up with appropriate catheter manipulations; and an integrated, cooperative approach whereby surgeons were willing to permit drainage to effect its benefits, rather than operating prematurely.

Abscess↗
PubMed1996

Magnetic resonance imaging of the upper airway. Effects of propofol anesthesia and nasal continuous positive airway pressure in humans.

BACKGROUND: Anesthetic agents inhibit the respiratory activity of upper airway muscles more than the diaphragm, creating a potential for narrowing or complete closure of the pharyngeal airway during anesthesia. Because the underlying mechanisms leading to airway obstruction in sleep apnea and during anesthesia are similar, it was hypothesized that anesthesia-induced pharyngeal narrowing could be counteracted by applying nasal continuous positive airway pressure (CPAP). METHODS: Anesthesia was induced in ten healthy volunteers (aged 25-34 yr) by intravenous administration of propofol in 50-mg increments every 30-s to a maximum of 300 mg. Magnetic resonance images of the upper airway (slice thickness of 5 mm or less) were obtained in the awake state, during propofol anesthesia, and during administration of propofol plus 10 cm nasal CPAP. RESULTS: Minimum anteroposterior diameter of the pharynx at the level of the soft palate decreased from 6.6 +/- 2.2 mm (SD) in the awake state to 2.7 +/- 1.5 mm (P < 0.05) during propofol anesthesia and increased to 8.43 +/- 2.5 mm (P < 0.05) after nasal CPAP application. Anteroposterior diameter of the pharynx at the level of the dorsum of the tongue increased from 7.9 +/- 3.5 mm during propofol anesthesia to 12.9 +/- 3.6 mm (P < 0.05) after nasal CPAP. Pharyngeal volume (from the tip of the epiglottis to the tip of the soft palate, assuming this space to be a truncated cone) significantly increased from 2,437 +/- 1,008 mm3 during propofol anesthesia to 5,847 +/- 2,827 mm3 (P < 0.05) after nasal CPAP application. CONCLUSIONS: In contrast to the traditional view that relaxation of the tongue causes airway obstruction, this study suggests that airway closure occurs at the level of the soft palate. Application of nasal CPAP can counteract an anesthesia-induced pharyngeal narrowing by functioning as a pneumatic splint. This is supported by the observed reduction in anteroposterior diameter at the level of the soft palate during propofol anesthesia and the subsequent increase in this measurement during nasal CPAP application.

Adult↗
PubMed1996

Technical adequacy of fluoroscopic spot films of the gastrointestinal tract: comparison of residents and technologists.

OBJECTIVE: We compared images obtained during gastrointestinal fluoroscopy by specially trained and experienced technologists with those obtained by radiology residents to determine if the quality of images was similar between the two groups. MATERIALS AND METHODS: Three senior radiologists examined the fluoroscopic spot films of 80 patients who were divided evenly into four groups: barium enemas performed by technologists, barium enemas performed by residents, gastrointestinal series performed by technologists, and gastrointestinal series performed by residents. The senior radiologists graded adequacy of visualization of the esophagus, stomach, duodenum, and all parts of the colon. A grade of 1 was given for poor films, 2 for adequate films, and 3 for good films. They did not know who performed each study. RESULTS: For barium enemas, the residents' mean score was slightly higher than that of the technologists (13.5 compared with 12.9). For gastrointestinal series, residents' mean score was again slightly higher (20.5 compared with 19.7). In neither case did the difference reach statistical significance. CONCLUSION: Fluoroscopic films obtained by residents and by specially trained and experienced technologists for barium enemas or gastrointestinal series were statistically indistinguishable.

Allied Health Personnel↗
PubMed1995

Transrectal ultrasound-guided transperineal cryoablation in the treatment of prostate carcinoma: preliminary results.

PURPOSE: We studied ultrasound-guided percutaneous cryoablation for treatment of prostate carcinoma. MATERIALS AND METHODS: Our series includes 83 individuals who underwent transrectal ultrasound-guided transperineal percutaneous cryoablation of the prostate. Prostate specific antigen levels, biopsy results and complications were assessed at 3 months. RESULTS: Of 61 biopsies 8 (13.1%) were positive for carcinoma (half showed stage D disease). Of patients with stages T1 to T3 cancer 92.6% were free of disease at 3 months. Prostate specific antigen levels were significantly decreased by an average of 1.90 ng./ml. (p < 0.05). Major complications were infrequent, including bladder perforation in 1 patient, urethral strictures in 3, bladder outlet obstruction in 2 and partial incontinence in 2. Impotence was frequent but transient. CONCLUSIONS: Transrectal ultrasound-guided transperineal percutaneous cryoablation of the prostate produces few major complications and appears at 3 months to be effective in eradicating local prostate tumors. Longer followup is required to test the original hypothesis.

Adult↗