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Hans-Jørgen Smith

Publications and source records attributed to Hans-Jørgen Smith.

17 recordsLinked to original sources
PubMed2007

Sonography of the rotator cuff in painful shoulders performed without knowledge of clinical information: results from 58 sonographic examinations with surgical correlation.

PURPOSE: To assess the value of sonography as an isolated diagnostic test for the detection and quantification of rotator cuff tears. METHODS: Preoperative sonographic examination was performed on 58 shoulders. Key biases on sonographic interpretation such as history-taking, physical examination, or concurrent imaging examinations were excluded by way of blinding. Tears of the rotator cuff were the positive findings of interest. Assessment of tear size and localization was done sonographically, and the results were compared with operative findings. RESULTS: All 24 full-thickness tears observed at surgery had been diagnosed correctly via sonography. In 19 of 20 cases with an intact rotator cuff, preoperative sonography was negative. Thirteen of 14 partial-thickness tears were not detected via sonography; 1 was misinterpreted as a full-thickness tear. Location of the tears relative to the rotator cuff tendons was described correctly in 21 of 25 cases. For tear size measurement, the 95% range of agreement was less than +/-1 cm. CONCLUSIONS: Blinded sonographic examination is effective in the detection and quantification of full-thickness tears of the rotator cuff but lacks sensitivity in the detection of partial-thickness tears.

Adolescent↗
PubMed2006

Clinical and radiologic outcome of off-pump coronary surgery at 12 months follow-up: a prospective randomized trial.

BACKGROUND: After more than a decade of experience with off-pump coronary bypass surgery, still no consensus exists concerning its benefit on clinical outcome compared to the on-pump technique. In this 12-month follow-up, we compare off-pump and on-pump surgery on the appearance of graft patency, myocardial function, and clinical outcome. METHODS: One hundred twenty patients were randomized to off-pump or on-pump coronary surgery. Angiography was performed intraoperatively, at 3 and 12 months. Global myocardial function was estimated by magnetic resonance imaging (MRI) preoperatively and 12 months postoperatively, as well as functional class and stress testing. RESULTS: After 12 months internal mammary artery patency was 94% in the off-pump group and 96% in the on-pump group. Vein graft patency was 80% and 87%, respectively. No statistically significant difference between the two groups existed. There were no differences in exercise capacity improvement and attenuation of symptoms between the groups. CONCLUSIONS: At 12-months follow-up, off-pump coronary bypass surgery provided the same angiographic graft patency as the on-pump technique. Improvement in functional class and exercise capacity was the same in both groups.

Aged↗
PubMed2006

Diagnostic accuracy of magnetic resonance and endoscopic retrograde cholangiography in primary sclerosing cholangitis.

BACKGROUND & AIMS: To evaluate the accuracy and interobserver variability of magnetic resonance cholangiography (MRC) and endoscopic retrograde cholangiography (ERC) in the diagnosis of primary sclerosing cholangitis (PSC). METHODS: MRC at 1.5 T with thin- and thick-slice breath-hold technique was performed in 66 adult patients (median age, 44 y; 26 women) with an appropriate spectrum of hepatobiliary diseases. Maximum intensity projection images were reconstructed from the thin slices. ERC was performed within 48 hours of the MR examination. The reference standard of PSC diagnosis was based on a combination of clinical features and cholestatic biochemical profile with typical ERC and/or MRC abnormalities and supported by liver histology findings. Two independent reviewers who were unaware of final diagnoses analyzed all images retrospectively. RESULTS: PSC was diagnosed in 39 (59%) of 66 patients. MRC provided comparable and poorer depiction than ERC of extrahepatic and intrahepatic ducts, respectively. However, the diagnostic accuracy of ERC and MRC were comparable. In the MRC detection of PSC, the average sensitivity of 2 independent readers was 80%, the specificity was 87%, and the accuracy was 83%. The corresponding values for ERC were a sensitivity of 89%, a specificity of 80%, and an accuracy of 85%. Interobserver agreement for the diagnosis of PSC was good (kappa = .61) for MRC and excellent (kappa = .81) for ERC. CONCLUSIONS: PSC can be diagnosed with high accuracy and good interobserver agreement. MRC and ERC performed equally well in the diagnosis of PSC when used blinded to clinical information.

Adolescent↗
PubMed2006

Magnetic resonance imaging of the Harderian gland in piglets.

The main purpose of the present study was to investigate the value and effectiveness of functional and morphological magnetic resonance imaging (MRI), in order to assess the extent of brain injury in a hypoxic-ischaemic piglet model, and further to validate that the ischaemic injury was successfully induced. In this way, we also characterized the Harderian gland. MRI was performed at 1.5 T in anaesthetized piglets (n = 10, 12-36 h of age). Magnetic resonance perfusion and diffusion imaging were performed at different time points, before, during and after the induction of hypoxia-ischaemia. The effects following bilateral clamping of the carotid arteries were also assessed by contrast-enhanced magnetic resonance angiography. Morphological assessment included T1- and T2-weighted imaging, and fat-suppressed T1-weighted imaging before and after contrast medium enhancement. Morphological MRI revealed a prominent, well-defined structure located at the eyeball. Magnetic resonance angiography reconstructed with volume rendering showed this structure to be partially enclosed by large venous sinuses. At dissection, when compared with the magnetic resonance images, the deep gland of the third eyelid, the Harderian gland, corresponded to this structure both in topography and in size. By contrast, the lacrimal gland proper presented as a small, soft and pale structure that was difficult to distinguish from the surrounding connective tissue. At histological examination, the Harderian gland consisted mainly of compact areas of tubuloacinar glands with abundant eosinophilic granules. The present MRI demonstration of the Harderian gland was an accidental finding during an investigation to assess the extent of brain injury in a hypoxic-ischaemic piglet model. The combination of MRI and histology made it possible to detect and describe the Harderian gland in pig. It has generally been studied in rodents and lower vertebrates and is reported to possess various endocrine and exocrine functions.

Animals↗
PubMed2006

Use of magnetic resonance imaging to define the anatomical location closest to all three cords of the infraclavicular brachial plexus.

Infraclavicular techniques are often used to perform brachial plexus blocks. In our volunteer study we used magnetic resonance imaging to identify the brachial plexus and axillary vessels in a sagittal plane corresponding to the lateral sagittal infraclavicular block. In 20 volunteers, all cords were positioned within 2 cm from the artery approximately within 2/3 of a circle. We derived an injection site that was closest to all cords, cranio-posterior and adjacent to the axillary artery. We conclude that this knowledge may be useful for the performance of infraclavicular blocks aided by ultrasound. However, our proposals should be tested by clinical studies.

Adult↗
PubMed2005

New noninvasive method for assessment of left ventricular rotation: speckle tracking echocardiography.

BACKGROUND: Left ventricular (LV) torsion is due to oppositely directed apical and basal rotation and has been proposed as a sensitive marker of LV function. In the present study, we introduce and validate speckle tracking echocardiography (STE) as a method for assessment of LV rotation and torsion. METHODS AND RESULTS: Apical and basal rotation by STE was measured from short-axis images by automatic frame-to-frame tracking of gray-scale speckle patterns. Rotation was calculated as the average angular displacement of 9 regions relative to the center of a best-fit circle through the same regions. As reference methods we used sonomicrometry in anesthetized dogs during baseline, dobutamine infusion, and apical ischemia, and magnetic resonance imaging (MRI) tagging in healthy humans. In dogs, the mean peak apical rotation was -3.7+/-1.2 degrees (+/-SD) and -4.1+/-1.2 degrees, and basal rotation was 1.9+/-1.5 degrees and 2.0+/-1.2 degrees by sonomicrometry and STE, respectively. Rotations by both methods increased (P<0.001) during dobutamine infusion. Apical rotation by both methods decreased during left anterior descending coronary artery occlusion (P<0.007), whereas basal rotation was unchanged. In healthy humans, apical rotation was -11.6+/-3.8 degrees and -10.9+/-3.3 degrees, and basal rotation was 4.8+/-1.7 degrees and 4.6+/-1.3 degrees by MRI tagging and STE, respectively. Torsion measurement by STE showed good correlation and agreement with sonomicrometry (r=0.94, P<0.001) and MRI (r=0.85, P<0.001). CONCLUSIONS: The present study demonstrates that regional LV rotation and torsion can be measured accurately by STE, suggesting a new echocardiographic approach for quantification of LV systolic function.

Animals↗
PubMed2005

Diagnostic ultrasound of the shoulder--a method for experts only? Results from an orthopedic surgeon with relative inexpensive compared to operative findings.

BACKGROUND: Diagnostic ultrasound examination of the shoulder is generally considered to require long experience. We examined the results of an orthopedic surgeon with little experience of ultrasound. PATIENTS AND METHODS: A relatively inexperienced examiner performed preoperative ultrasound scanning of 79 patients with symptoms from the rotator cuff and/or the long head of the biceps muscle. Tears of the rotator cuff and rupture or dislocation of the long head of the biceps muscle were the positive findings of interest. Results were compared to operative findings. RESULTS: In 66 of 79 shoulders, ultrasonographic rotator cuff findings were confirmed at surgery (accuracy 84%). 20 of 26 full-thickness tears were diagnosed correctly. 6 of 7 partial-thickness tears were overlooked. Ultrasound was false positive in 1 case. For the long head of the biceps muscle, all 8 cases of dislocation or rupture of the tendon were diagnosed but differentiation between the two conditions was not possible in 2 cases. INTERPRETATION: Our results may encourage orthopedic surgeons to start using ultrasound as a diagnostic technique for full-thickness tears of the rotator cuff and for pathology in the long head of the biceps muscle.

Clinical Competence↗
PubMed2005

The vertical infraclavicular brachial plexus block: a simulation study using magnetic resonance imaging.

The recommended needle trajectory for the vertical infraclavicular brachial plexus block is anteroposterior, caudad to the middle of the clavicle. We studied the risk of pneumothorax and subclavian vessel puncture and the precision of this method by using magnetic resonance imaging in 20 adult volunteers. The trajectory aimed at the lung in six subjects, five of whom were women. However, pleural contact could be avoided in all subjects by halting needle advancement after contact with the subclavian vessels, plexus, or first rib. The subclavian vein was reached by the trajectory in three and the subclavian artery in five subjects. The trajectory had a median distance to the plexus (closest aspect) of 1 mm (range, 0-9 mm) and contacted the nerves in 9 subjects. In conclusion, there is a small probability that the needle may reach the pleura when a vertical infraclavicular brachial plexus block is performed, particularly in women, and a high probability that it will contact the subclavian vein or artery. Although the trajectory is close to the plexus, any medial deviation carries the risk of pleural or subclavian vessel contact at other depths. Clinical accuracy in defining the insertion point is critical.

Adult↗
PubMed2004

[Use of MR imaging in the diagnosis of cardiac disease].

BACKGROUND: Imaging plays an important part in cardiology, and MR imaging (MRI) is one of many methods used in the diagnosis of cardiac disease. MATERIAL AND METHODS: Based on the literature and own experience, an overview is given of the current potential of MRI in cardiology. RESULTS: MRI represents the most comprehensive diagnostic modality in cardiac imaging. Non-invasively and without the use of ionizing radiation, MRI may depict the anatomy in freely selectable planes, visualise and quantify cardiac pump function and valvular function, and provide detailed information on myocardial contractility, perfusion, and viability. MRI may give valuable, sometimes unique contributions in both congenital and acquired heart disease. INTERPRETATION: Restricted availability and experience have slowed the spread of cardiac MRI, but the method is expected to play a major role in the diagnosis of cardiac disease.

Cardiomyopathies↗
PubMed2004

[Ultrasound examination of the shoulder--a method description].

Ultrasound examination of the shoulder in orthopaedics is not much used in Norway, but it is an established method in many institutions abroad. According to the literature, good results have been obtained with diagnostic ultrasound for demonstration of rotator cuff ruptures and abnormalities of the long tendon of the biceps muscle. In order to increase the knowledge of this diagnostic modality in Norway, we present the general principles and techniques of shoulder ultrasonography. Examples of normal and pathological ultrasound findings in the rotator cuff and long tendon of the biceps muscle are given.

Bursitis↗
PubMed2004

Morphological and hemodynamic magnetic resonance assessment of early neonatal brain injury in a piglet model.

PURPOSE: To investigate the utility of functional and morphological magnetic resonance imaging (MRI) to assess the extent of brain injury in a hypoxia-ischemia (HI) piglet model and further to validate that the desired ischemic injury was successfully induced. MATERIALS AND METHODS: MRI was performed at 1.5 T in anesthetized piglets (N = 10, age = 12-36 hours). Relative cerebral blood flow (rCBF), time-to-peak (TTP) contrast, and apparent diffusion coefficient (ADC) were estimated at different time points pre-, during, and post-HI. The effect following bilateral clamping of the carotid arteries was assessed by contrast-enhanced MR angiography (MRA) and phase contrast MR angiography (PCA) (N = 4). RESULTS: A linear correlation was observed between relative cerebral perfusion reduction and cerebral ADC during HI (r(2) = 0.85, P < 0.05). There was no correlation between rCBF reduction during 30 minutes of HI and cerebral ADC after 30 or 150 minutes of reperfusion/reoxygenation (RR). CONCLUSION: The combination of morphological and functional (perfusion and diffusion) MRI enabled consistent assessment of both the presence and absence of complete occlusion as well as the functional significance of the occlusion.

Animals↗
PubMed2004

Intraoperative angiography leads to graft revision in coronary artery bypass surgery.

BACKGROUND: Graft anastomosis quality in coronary artery bypass surgery can be assessed by intraoperative angiography. The aim of the present study was to quantify the on-table revision rate initiated by intraoperative angiography. METHODS: Intraoperative angiography was carried out in 186 patients undergoing coronary artery bypass surgery, with a total of 427 grafts. The operation was performed on-pump in 34%, off-pump through a sternotomy in 49%, and as a minimally invasive direct coronary bypass grafting (MIDCAB) procedure in 17%. The angiography was performed intraoperatively while the patients were still in general anesthesia, with the possibility for on-table revision. Follow-up angiography was carried out after a mean of 346 days. RESULTS: Eighteen of 427 grafts (4.2%) were revised due to the findings at intraoperative angiography. Revision rate after on-pump surgery was 1.1%, after off-pump through a sternotomy 6.4%, and after MIDCAB 6.5%. In 6 patients the lesions were located at the distal anastomoses and in 12 patients in the conduit. All but one was successfully revised, and at 1-year follow-up all these 17 grafts were patent. CONCLUSIONS: Intraoperative angiography saves a potential number of grafts that otherwise could have been occluded. An increased implementation of intraoperative quality assessment in coronary artery bypass surgery can lead to improved outcome.

Adult↗
PubMed2004

Coronary artery aneurysms mimicking cardiac tumor.

AIMS: To discuss the diagnosis of giant coronary aneurysms. METHODS AND RESULTS: We describe three patients in whom initial echocardiographic findings suggested cardiac tumors in the right atrium. Additional examination proved the tumor-like structures to be giant atherosclerotic coronary aneurysms of either the right coronary artery or its saphenous vein coronary bypass graft. CONCLUSION: Giant coronary aneurysms are an important differential diagnosis for cardiac tumors.

Aged↗
PubMed2004

A novel infraclavicular brachial plexus block: the lateral and sagittal technique, developed by magnetic resonance imaging studies.

UNLABELLED: A new infraclavicular brachial plexus block method has the patient supine with an adducted arm. The target is any of the three cords behind the pectoralis minor muscle. The point of needle insertion is the intersection between the clavicle and the coracoid process. The needle is advanced 0 degrees -30 degrees posterior, always strictly in the sagittal plane next to the coracoid process while abutting the antero-inferior edge of the clavicle. We tested the new method using magnetic resonance imaging (MRI) in 20 adult volunteers, without inserting a needle. Combining 2 simulated needle directions by 15 degrees posterior and 0 degrees in the images of the volunteers, at least one cord in 19 of 20 volunteers was contacted. This occurred within a needle depth of 6.5 cm. In the sagittal plane of the method the shortest depth to the pleura among all volunteers was 7.5 cm. The MRI study indicates that the new infraclavicular technique may be efficient in reaching a cord of the brachial plexus, often not demanding more than two needle directions. The risk of pneumothorax should be minimal because the needle is inserted no deeper than 6.5 cm. However, this needs to be confirmed by a clinical study. IMPLICATIONS: A new infraclavicular brachial plexus block method was investigated using magnetic resonance imaging without inserting needles in the volunteers. The study suggests two needle directions for performance of the block and that the risk of lung injury should be minimal. Expectations need to be confirmed by a clinical study.

Adult↗
PubMed2002

The importance of intraoperative angiographic findings for predicting long-term patency in coronary artery bypass operations.

BACKGROUND: The quality of anastomosis is the cornerstone in coronary artery bypass operations. Intraoperative coronary angiography confirms graft patency with the possibility to revise graft failure. The aim of this study was to describe the lesions found at "on-table" angiography, and to evaluate the significance of these immediate angiographic findings for the long-term patency. METHODS: A total of 57 grafts (42 left internal mammary artery grafts and 15 saphenous vein grafts) in 45 patients who underwent off-pump coronary artery bypass operations were included. On-table angiography was carried out with fixed angiographic equipment installed in the operating room. Follow-up angiographies were performed at 3 months and at 12 months. RESULTS: The most frequent finding in an on-table angiogram was spasm, which was not present at follow-up. Out of nine kinks, only one developed into a significant stenosis at follow-up. Of 44 grafts that were normal on-table, 37 (84%) were normal at the follow-up. Of 11 grafts with significant lesions on-table, eight (73%) were normal at the follow-up. Five percent of the grafts were revised because of the on-table angiography. CONCLUSIONS: On-table angiograms can be occasionally difficult to interpret because not all findings are important for later patency. Optimal results on-table predict good long-term results with a negative predictive value of 0.84, whereas significant lesions on-table have less impact on the follow-up results because the positive predictive value was only 0.38.

Adult↗