Automated analysis of data is inferior to visual analysis of ambulatory sleep apnea monitoring

BACKGROUND: Many ambulatory sleep apnea monitoring devices are equipped with software which allows an automated analysis of data as well as a visual analysis. OBJECTIVE: The Merlin system which records heart rate, snoring sound, efforts, oronasal flow, body position and oxygen saturation was investigated to identify proper parameter settings for the automated analysis and to compare the automated with the visual analysis in patients with mild obstructive sleep apnea syndrome (OSAS). Sensitivity and specificity of the visual and automated analysis of ambulatory monitoring in comparison with visual polysomnographic (PSG) analysis were determined. METHODS AND RESULTS: First, we tried to find the optimal parameters for the automated analysis, using 7 different settings in 17 OSAS patients. Furthermore, we applied the optimized setting to 66 OSAS patients who were admitted (age 50.9 +/- 9.9 years, BMI 32.9 +/- 5 kg/m(2)), and compared the results with the visual analysis of raw data. The patients slept for one night in the sleep laboratory with Merlin and PSG simultaneously to compare the visual and automated analysis of Merlin data with results from the visual analysis of PSG. Automated analysis leads to an underestimation of the respiratory disturbance index (RDI; p < 0.001) compared with both the visual analysis and results of PSG. Using a cutoff level of 5 apneas and hypopneas/h for the diagnosis of OSAS, the sensitivity of Merlin with the automated analysis is 40.6% and the specificity is 100%. With a cutoff level of 15/h, sensitivity and specificity rose to 91.3 and 100%, respectively, which is comparable to the visual analysis. CONCLUSION: Merlin is a reliable device for detection of sleep-related breathing disorders, but recordings should be analyzed visually, especially in patients with a low RDI.     

Advances in ureteral stent design

BACKGROUND AND PURPOSE: Ureteral stents are widely used in patients with urologic disorders. This review critically evaluates the recent literature, providing an update on advances in the development and design of stents. METHODS: A thorough MEDLINE and PubMed literature search on ureteral stents was performed, and all pertinent articles were reviewed in detail. This review was formulated on the basis of these articles, encompassing both basic science and clinical aspects of advances in ureteral stent design. RESULTS: The advances in development and design have been directed primarily toward decreasing stent-related morbidity such as discomfort, bladder irritability, infection, encrustation, and the need for an additional cystoscopic procedure to remove the stent. In recent years, there have been many significant advances in the design of ureteral stents, including tapered distal ends, and construction, such as magnetic, biodegradable, and tissue-engineered materials. CONCLUSIONS: There are many different bulk materials and coatings available for the manufacturing of ureteral stents, many of which are new. However, the ideal biomaterial has yet to be discovered. With ongoing research in this area, further advances in ureteral stent design will continue to improve outcomes for patients who require stents. Future advances are likely to include drug-coated stents, drug-eluting stents, and localized stenting techniques such as endoluminal gel paving.     

Pre- and inter-hospital transport of severely head-injured patients in rural Northern Norway

The purpose of this study was to survey the time consumed during the pre- and inter-hospital transport of severely head injured patients in Northern Norway. All patients (n = 85) operated for an intracranial mass lesions within 48 h after injury during the 10-year period 1986-1995 were included in this retrospective analysis. Ambulance records, transfer notes, and hospital records were reviewed. The transport of patients was classified as either direct from the trauma scene to the University Hospital (direct admission group) or as an inter-hospital transfer (transfer group). Forty-seven (55%) patients were in the direct admission group, and 38 (45%) were transferred through another hospital. The majority of patients (81%) were transported by air ambulance. Median time from injury to arrival in the emergency room was 5 (1-44) h. Time necessary for transport was significantly (p < 0.001) shorter in the direct admission group (median 3 h) compared to the transfer group (median 8 h). The inter-hospital transfer time was < or = 3 h in 17%. Clearly, the advanced air ambulance service in Northern Norway makes rapid inter-hospital transfer possible despite extremely long geographical distances. Our findings indicate that this possibility is not always utilized.     

Differential diagnosis of tailgut cyst in the case of a rectal carcinoma with presacral mass

Cystic masses of various different origins and degrees of malignancy occur in the presacral space. Apart from benign, malignant and acute inflammatory masses, the benign lesions include a group of cystic structures to which the dysgenetic cysts belong. The tailgut cyst is a relatively rare type of gastrointestinal origin from this group. We present the case of a stenosing rectal carcinoma in which a presacral mass was additionally found, which did not get smaller compared to the rectal tumour during combined preoperative radiochemotherapy, with a lymphoma being suspected. After extirpation of the tumour, histopathological processing revealed a stenosing rectal carcinoma with an adjacent dysgenetic lesion--a tailgut cyst. Although dysgenetic lesions are rare as presacral masses, this must also be taken into account as a differential diagnosis in the various imaging procedures such as endosonography, CT and MRT when a rectal carcinoma is present.     

Eagle syndrome: diagnostic imaging and therapy

In the case of clinical symptoms such as dysphagia, foreign-body sensation and chronic neck or facial pain close to the ear, an Eagle syndrome should be considered in the differential diagnosis. Rational diagnostics and therapy are elucidated on the basis of four case reports. Four patients presented in the outpatients clinic with chronic complaints on chewing and a foreign-body sensation in the tonsil region. Upon specific palpation below the mandibular angle, pain radiating into the ear region intensified. In all patients, local anaesthesia with lidocaine only led to a temporary remission of symptoms. Imaging diagnostics then performed initially included cranial survey radiograms according to Clementschitsch as well as in the lateral ray path and an OPTG. An axial spiral-CT was then performed using the thin-layer technique with subsequent 3-D reconstruction. Therapy consisted of elective resection with a lateral external incision from the retromandibular. From a symptomatic point of view, the cranial survey radiograms and the OPTG revealed hypertrophic styloid processes. The geometrically corrected addition of the axial CT images produced an absolute length of 51-58 mm. The 3-D reconstruction made it possible to visualise the exact spatial orientation of the styloid processes. An ossification of the stylohyoid ligament could definitely be ruled out on the basis of the imaging procedures. After resection of the megastyloid, the patients were completely free of symptoms. Spiral-CT with subsequent 3-D reconstruction is the method of choice for exact determination of the localisation and size of a megastyloid, while cranial survey radiograms according to Clementschitsch and in the lateral ray path or an OPTG can provide initial information. The therapy of choice is considered to be resection of the megastyloid, whereby an external lateral incision has proved effective.     

Methylation-specific PCR for DNA-based detection of occult tumor cells in lymph nodes of prostate cancer patients

OBJECTIVES: To assess the feasibility of methylation-specific PCR (MSP) for the detection of promoter hypermethylation of the detoxifying glutathione-S-transferase P1 gene (GSTP1) to detect occult prostate cancer cells in lymph nodes (LNs). METHODS: Paraffin-embedded pelvic LNs from 20 patients with pT2pN0M0R0 prostate cancer who developed PSA relapse were assessed by MSP. In 18 of the patients, samples of the primary tumor were obtained for MSP. In 19 patients, bone marrow (BM) aspirates were analyzed preoperatively for disseminated tumor cells by immunocytochemistry (mAb A45-B/B3). In 16 patients, biopsies of the anastomotic region were performed following PSA relapse. As a negative control GSTP1 methylation status was also assessed in LNs from 9 patients for whom an autopsy was performed for non-cancer-related causes. RESULTS: All primary tumors displayed GSTP1 hypermethylation (HM). Preoperative BM assessment showed disseminated tumor cells in 8/20 cases (40%). In 4 patients, biopsies of the vesico-urethral anastomosis showed local tumor recurrence. The LNs in the cancer patients showed GSTP1 HM in 18/20 cases (90%) versus 1/9 patients (11.1%) in the non-cancer cohort (p<0.0001). CONCLUSION: GSTP1 HM appears to be well suited for molecular staging of prostate cancer and accurately detects disseminated tumor cells in LNs, which was seen in 90% of the patients with PSA relapse. However, the limited number of patients and the finding of benign and malignant prostatic tissue at the vesico-urethral anastomosis as a putative local source of PSA recurrence does not allow us to draw conclusions on the prognostic significance of our findings, yet.     

Detection of Intestinal Ischemia Using a Microdialysis Technique in an Animal Model

Abstract The purpose of this study was to use a microdialysis technique to demonstrate the metabolic changes that occur in the intestinal wall during ischemia in vivo. Continuous monitoring of glucose, lactate, and glycerol using a microdialysis technique was performed in the jejunal wall of 10 pigs during steady-state and occlusive ischemia. The microdialysis catheters were introduced 50, 80, and 110 cm from the ligament of Treitz. Occlusive ischemia was established to two segments after steady state was reached. Microdialysate samples were collected from ischemic/nonischemic intestinal segments simultaneously every 20 minutes. For comparison with the microdialysis measurements, systemic blood samples were drawn from the cannulated femoral artery and analyzed consecutively. A significant increase of microdialysate lactate and a significant decrease of microdialysate glucose were found during occlusive ischemia as compared to the preischemic samples and samples from the nonischemic control catheters. The microdialysate glycerol increased during ischemia, but later than the lactate. No changes were observed in systemic serum lactate, serum glucose, pH, pco ₂, and po ₂, but serum potassium increased by 1.1 mmole (median) during ischemia. Microdialysis measured in the intestinal wall identifies local ischemia and may be a new method for the monitoring of intestinal perfusion.     

Impact of patient placement criteria on substance abuse treatment under the Oregon Health Plan

When Oregon shifted to managed care for Medicaid-funded substance abuse treatment, standardized patient placement and discharge criteria were rapidly implemented statewide. This prospective, naturalistic study examines the validity and impact of placement criteria with a sample of 240 adults presenting for treatment compared to a sample of 287 in Washington state, where implementation was phased in slowly. Baseline profile analysis suggested better differentiation between Level II and Level III clients for the Oregon sample and better implementation than with the Washington sample, presumably because Oregon clinicians received more training and had more experience with the criteria. A majority of the Oregon sample was placed in intensive outpatient programs, consistent with the recommended level of care. In this study, placement criteria showed good potential for changing treatment planning behavior, increasing individualization, and improving utilization of new levels of care.