Changes in lung parenchyma after acute respiratory distress syndrome (ARDS): assessment with high-resolution computed tomography.

The aim of this study was to evaluate the appearance, extent, and distribution of parenchymal changes in the lung after acute respiratory distress syndrome (ARDS) as a function of disease severity and therapeutic procedures. High-resolution computed tomography (HRCT), clinical examination, and lung function tests were performed in 15 patients, 6-10 months after ARDS. The appearance and extent of parenchymal changes were compared with the severity of ARDS, as well as with clinical and therapeutic data. Lung parenchymal changes resembling those found in the presence of pulmonary fibrosis were observed in 13 of 15 patients (87%). The changes were significantly more frequent and more pronounced in the ventral than in the dorsal portions of the lung ( p<0.01). A significant correlation was observed between the extent of lung alterations and the severity of ARDS ( p<0.01), and the duration in which patients had received mechanical ventilation either with a peak inspiratory pressure greater than 30 mmHg ( p<0.05), or with more than 70% oxygen ( p<0.01). Acute respiratory distress syndrome frequently is followed by fibrotic changes in lung parenchyma. The predominantly ventral distribution of these changes indicates that they may be caused by the ventilation regimen and the oxygen therapy rather than by the ARDS.

[The value of sonography in the intensive care unit for the diagnosis of diaphragmatic paralysis]. / Wertigkeit der Sonographie auf der Intensivstation zur Diagnostik von Zwerchfellparesen.

PURPOSE: To assess the value of bedside sonography in the detection of diaphragmatic paralysis in patients in the intensive care unit. METHODS: In this study, 100 patients who were admitted to the intensive care unit after thoracic operations were evaluated. Sonography of each hemidiaphragm was performed with coronal scans at the mid-axillary line on both sides with the patient supine. Absent and paradoxical diaphragmatic movement was considered to be indicative of diaphragmatic paralysis. All patients underwent additional fluoroscopy within 5 days. RESULTS: In 13 patients (13%) sonography revealed diaphragmatic paralysis. All these results were confirmed with fluoroscopy resulting in a sensitivity and specificity for sonography of 100%. CONCLUSION: Bedside sonography of the diaphragm at the intensive care unit is a reliable tool for diagnosing diaphragmatic paralysis.

MR imaging in children with nonperforated acute appendicitis: value of unenhanced MR imaging in sonographically selected cases.

OBJECTIVE: The aim of this study was to describe the MR appearance of acute appendicitis and to determine the value of MR imaging for diagnosis of acute appendicitis. SUBJECTS AND METHODS: Forty-five children (28 girls, 17 boys), 7-16 years old (mean age, 13 years old), with clinically diagnosed acute appendicitis underwent independently graded compression sonography by two radiologists. MR imaging was performed when sonography revealed acute appendicitis (observer 1, 16 [36%] patients; observer 2, 18 [40%] patients), was inconclusive (observer 1, two [4%] patients; observer 2, one [2%] patient), and was interpreted as normal (observer 1, two [4%] patients; observer 2, one [2%] patient) (n = 20). Axial T1-weighted turbo spin-echo sequences, T2-weighted turbo spin-echo sequences in the axial and coronal planes, and fat-suppressed short inversion time inversion recovery turbo spin-echo sequences in the axial plane (4-mm slice thickness) were obtained and evaluated independently by two radiologists. The ability to see acute appendicitis with MR imaging was evaluated, the appearance and morphologic changes were described, and the most accurate sequence was determined. All children in whom MR imaging was performed underwent surgery. RESULTS: MR imaging revealed acute appendicitis in all cases (100%) by both observers. On T2-weighted ultra turbo spin-echo images, acute appendicitis appeared with a markedly hyperintense center, a slightly hyperintense thickened wall, and markedly hyperintense periappendiceal tissue. Unenhanced axial T2-weighted spin-echo imaging was the most sensitive sequence. CONCLUSION: In this study group, MR imaging was a valuable technique for depiction of acute appendicitis.

[Prevalence of abdominal aortic aneurysms: a sonographic screening study]. / Prävalenz des abdominellen Aortenaneurysmas: Eine sonographische Screeningstudie.

PURPOSE: To determine the prevalence of abdominal aortic aneurysms (AAA) in males above 60 years of age. METHODS: 1043 males of 60 years of age or older underwent sonographic examinations of the abdominal aorta. All of the candidates had volunteered for the examination, and special care was taken to avoid preselection of the candidates. Wherever possible, information was obtained on the following risk factors: cholesterol level, nicotine, diabetes, insulin and other medication, hypertonia and cardiac risk. RESULTS: An AAA was diagnosed in 2.59% of the cases, while ectasia of the abdominal aorta was detected in 11.89%. The mean diameter of the aneurysms was 39.1 mm. Significant correlations between the various risk factors and abnormalities of the abdominal aorta could be established in patients suffering from angina pectoris (p = 0.004) and from congestive heart failure (p = 0.014). CONCLUSIONS: AAA in males above 60 occurs in 2,590 out of 100,000 cases. The most noteworthy risk factors in the development of AAA are cardiovascular disorders.

Role of magnetic resonance imaging in renal transplant recipients with acquired cystic kidney disease.

OBJECTIVES: To evaluate the impact of magnetic resonance imaging (MRI) in renal transplant recipients whose ultrasound (US) examinations of the native kidneys have met the criteria of acquired cystic kidney disease (ACKD). METHODS: The US scans of 840 renal allograft recipients were prospectively studied. In addition, 46 of 169 patients diagnosed with ACKD by US scans underwent MR examination. MRI protocols included (a) T1 and T2-weighted fast spin echo imaging, (b) T2-weighted gradient echo imaging, and (c) gadolinium-enhanced T1-weighted imaging in 7 patients with evidence of complex cysts. In the case of complex lesions, both US and MRI follow-up examinations were performed between 6 and 12 months after the prior examination. RESULTS: US examination showed ACKD in 169 of 840 patients. In addition, US revealed 8 patients with renal cell carcinomas (RCC). Of these 8 patients, 7 had evidence of ACKD. The median number of cysts depicted on US examination in native kidneys of renal transplant recipients was 3 (range 0 to 10) on both sides. MRI revealed significantly more and smaller cysts compared to US. The median number of cysts was seven on the left and nine on the right native kidneys, respectively. MRI revealed 18 complex lesions in 7 patients. Thirteen of 18 complex lesions were undetected by US. CONCLUSIONS: MRI is superior to US in depiction of simple and complex lesions of native kidneys in renal allograft recipients. MRI exhibits no overestimation of the prevalence of ACKD on the basis of the US criteria already mentioned. Advantages of MRI do not justify routine screening tests by this imaging modality. However, MRI should be used for further evaluation of complex lesions detected by US.

Reduction of adverse events in MRI of the breast by personal patient care.

PURPOSE: To determine the difference in anxiety reactions in patients undergoing standard (non-breast) magnetic resonance imaging (MRI) compared to breast magnetic resonance imaging (MRM) and to evaluate the influence of patient information before the breast imaging examination on the rate of premature termination of the procedure. MATERIALS AND METHODS: Over 2 years, 5837 non-breast and 336 breast magnetic resonance examinations were performed at our institution. One group of breast MRM patients (n = 144) received detailed information and a second group (n = 189) received only routine information before MRI. The rates of premature termination were recorded for all groups. RESULTS: In 0.5% (27/5837) of patients undergoing standard MRI examinations the study had to be stopped prematurely. Of the breast MRM patients, those who had received only routine information had a significantly higher rate of premature termination when compared to the better-informed patients and those undergoing standard MRI (5.5%, 10/189, P= 0.01). A significantly lower rate of premature termination occurred in the better-informed breast group (0%, 0/144). CONCLUSION: MRM is associated with an increase in patient anxiety and higher rates of incomplete examination than other MR procedures. We recommend careful patient preparation including detailed verbal information before MRM and support during the procedure to obtain optimal patient compliance.

Prognostic factors for swallowing rehabilitation following head and neck cancer surgery.

Thirty-two head and neck surgical patients with prolonged moderate to severe aspiration were assessed with videoendoscopic and videofluoroscopic swallowing studies to reveal all components of dysphagia and aspiration. All patients received functional swallowing therapy, and 75% of the patients regained full oral intake diet. The duration of non-oral feeding varied widely. The outcome of swallowing rehabilitation (success or failure, duration of non-oral feeding) was statistically correlated with preoperative tumour stage, patients' age, therapy onset, severity of aspiration and the results of the videofluoroscopic measurements of oral and pharyngeal transit time, pharyngeal delay time, duration of laryngeal closure and cricopharyngeal opening, hyoid and laryngeal elevation, presence or absence of a stenosis at the pharyngoesophageal segment. The following factors proved to be statistically significant for the prognostic estimate of swallowing rehabilitation: preoperative tumour stage, therapy onset, and severity of aspiration. For postoperative swallow recovery, an early therapy onset after thorough diagnostics with videoendoscopic and videofluoroscopic swallowing studies is recommended. Videofluoroscopic measurements will yield some prognostic estimate of oropharyngeal dysphagia and aspiration. Videoendoscopy, by it's availability and immediacy, proved to be useful for monitoring the course of rehabilitation.

Vasoactive intestinal peptide and somatostatin receptor scintigraphy for differential diagnosis of hepatic carcinoid metastasis.

We report a case of a hepatic carcinoid metastasis mimicking a hemangioma on ultrasound and on CT. Indium-111-DTPA-D-Phe-1-octreotide (111In-OCT) and 123I-vasoactive intestinal peptide (123I-VIP) receptor images suggested a carcinoid metastasis of the liver. The final diagnosis was established histopathologically. The differential diagnosis of liver lesions is discussed.

Diaphragmatic dysfunction after heart or lung transplantation.

BACKGROUND: The aim of this study was to evaluate the incidence and outcome of diaphragmatic dysfunction in patients after heart or lung transplantation and to assess the value of bedside sonography for the detection of diaphragmatic dysfunction. METHODS: We prospectively evaluated 33 heart transplant recipients and 27 lung transplant recipients by use of sonography of the diaphragm and fluoroscopy. RESULTS: Diaphragmatic dysfunction, diagnosed with ultrasonography and confirmed with fluoroscopy, was present in four heart transplant recipients (12.1%) and two lung transplant recipients (7.4%) and such dysfunction led to a statistically significant higher incidence of pneumonia during hospitalization and a nonstatistically significant increased length of intubation compared with patients with normal diaphragmatic function. CONCLUSION: Diaphragmatic dysfunction, which can be reliably diagnosed with bedside sonography, is common after heart and lung transplantation and seems to have a negative influence on patient recovery.

Intraoperative and early postoperative colour Doppler sonography after carotid artery reconstruction: follow-up of technical defects.

We studied 50 patients with intraoperative colour-coded Doppler sonography (CCDS) after carotid artery reconstruction. Technical defects could be detected in 19 cases (38 %): residual plaques in 9, flaps in 8 and strictures in 2. In 9 cases (18 %) the carotid endarterectomy was revised. One residual plaque and one residual stricture caused thrombosis at the operative site a few hours postoperatively. One of the patients with residual plaques developed a high-grade stenosis within the follow-up period. Of the patients with residual plaques two had a medium-grade stenosis at follow-up. Six flaps decreased in size or disappeared within 1 week after operation. No patient with a flap developed a stenosis within the follow-up period. Our findings seem to indicate that correction of intimal flaps less than 10 mm in size is not necessary.

Distinction between hepatic focal nodular hyperplasia and malignant liver lesions using technetium-99m-galactosyl-neoglycoalbumin.

UNLABELLED: Distinction between hepatic focal nodular hyperplasia (FNH) and malignant liver lesions is essential because of the different therapy strategies, since FNH can be managed conservatively. The aim of this study was to describe the imaging pattern of FNH using the hepatocyte receptor ligand 99mTc-galactosyl-neoglycoalbumin 99mTc-NGA) and to assess the value of this receptor imaging agent in the differentiation of FNH from malignant liver lesions. METHODS: Twelve consecutive patients with histologically confirmed FNH were investigated. The FNH-lesions were asymptomatic and incidentally found by ultrasonography. Nine patients with histologically verified hepatocellular carcinomas and three patients with liver metastases spread from gastrointestinal adenocarcinomas served as controls. RESULTS: All FNH lesions showed normal or even increased uptake of 99mTc-NGA. Whereas malignant liver lesion-to-normal liver ratios amounted to 0.4 +/- 0.2 (mean +/- s.d.), FNH lesion-to-normal liver ratios were 1.7 +/- 0.3 (mean +/- s.d.). CONCLUSION: The receptor imaging agent 99mTc-NGA with concurrent use of SPECT is useful in the differential diagnosis of FNH and malignant hepatic tumors.

Pseudopericardial effusions in heart transplant recipients.

BACKGROUND: The objective of this study was to determine the nature of sonographically observed band-shaped, homogeneous, almost echo-free structures located ventral to the right ventricle of the heart in heart transplant recipients. METHODS: A total of 212 consecutive heart transplant recipients was evaluated sonographically. RESULTS: In 18 of the 212 patients (8.5%) band-shaped structures were detected, and these structures were proved with computed tomography or magnetic resonance imaging to be caused by mediastinal fat. CONCLUSIONS: A sonographically demonstrable, almost echo-free band-shaped structure located ventral to the heart should not be misinterpreted as localized pericardial effusion.

Coefficient of variation: a powerful Doppler ultrasonographic parameter for detection of renal artery stenosis.

The aim of our study was to objectively compare the effectiveness of various Doppler parameters in the diagnosis of renal artery stenosis. In three sheep, variable degrees of renal artery stenosis were induced and renal segmental arteries were investigated using pulsed Doppler sonography. In each animal the standard deviation of the instantaneous peak velocity within one cardiac cycle normalized by the mean peak velocity (coefficient of variation) had significantly higher normalized regression coefficients (k* = -0.215, average of three animals) when compared to resistive index (k* = -0.090) and acceleration index (k* = -0.069). In each individual animal, coefficient of variation detected lower pressure gradients (6.3 mm Hg, average value) than did resistive index (13.4 mm Hg) or acceleration index (17.3 mm Hg). The coefficient of variation may detect the presence of pressure gradients in renal artery stenosis more accurately than acceleration index or resistive index.

Use of resistance index for the diagnosis of breast tumours.

AIM: To determine whether the resistance index (RI) contributes to the differential diagnosis of breast masses. PATIENTS AND METHODS: In 56 breast tumours colour-coded Doppler sonography was performed and their resistance indices calculated from their spectral Doppler tracings. Histologic evaluation was obtained by excision biopsy. RESULTS: In seven of 28 benign tumours (25%) no lesion was seen on ultrasound. In another seven benign tumours, no intratumoral vessels were demonstrated. The resistance index of the remaining 14 lesions (50%) varied between 0.5 and 0.75 with a mean value of 0.62 (standard deviation 0.08). Ultrasound missed one of 28 carcinomas (3.5%) and in one other tumour (3.5%) no flow was demonstrable. The resistance index of 26 malignant tumours varied between 0.56 and 0.9 with a mean value of 0.7 (standard deviation 0.08). CONCLUSION: Breast malignancies have higher resistance indices with a wider range as assessed by colour-coded Doppler ultrasound (81% exceed 0.6) than do benign lesions. Due to the considerable overlap of the range of the resistance index, the measurements in any single patient may not be diagnostic. The absence of flow does not definitively exclude malignancy.

Globus sensation: value of static radiography combined with videofluoroscopy of the pharynx and oesophagus.

Pharyngo-oesophageal abnormalities are found in a high proportion of patients with globus sensation. This study compares the diagnostic value of static single- and double-contrast radiography of the pharynx and oesophagus with videofluoroscopy and with videofluoroscopy combined with static radiography in these patients. Pharyngeal and oesophageal morphology and motor function were studied in 130 consecutive patients with globus sensation (46 males, 84 females; mean age, 47 years) by means of static single and double-contrast radiography and by videofluoroscopy. Videofluoroscopy revealed significantly more functional and structural abnormalities compared to static radiography. Pharyngeal and/or oesophageal disorders were found in 89 vs. 47 patients (chi2 [1] = 19.82, P = 0.0001), pharyngeal abnormalities in 54 vs. 27 patients (chi2 [1] = 13.5, P < 0.0002), and oesophageal abnormalities in 72 vs. 27 patients (chi2 [1] = 28.13, P < 0.0001). Videofluoroscopy combined with static radiography revealed significantly more abnormalities than videofluoroscopy alone (chi2 [1] = 4.23, P < 0.05), and assessed mucosal details more reliably than videofluoroscopy alone. The most frequent abnormalities found were nonspecific oesophageal motor disorders, pharyngo-oesophageal sphincter dysfunction, pharyngeal stasis, achalasia, and laryngeal penetration or aspiration of barium. In most patients with globus sensation, pharyngeal and/or oesophageal abnormalities can be detected radiographically. Videofluoroscopy revealed significantly more functional but not morphological abnormalities than did static radiography. Videofluoroscopic studies combined with static radiography had a higher diagnostic value than videofluoroscopic studies alone.

Intrarenal Doppler ultrasonography: which vessel should be investigated?

The aim of our study was to determine whether the site of intrarenal Doppler measurement influences diagnosis of renal artery stenosis. In an experimental test, three sheep with variable degrees of renal artery stenosis were investigated. In each animal, the resistive index from renal segmental arteries correlated better with mean pressure gradient (r = 0.85, 0.71, 0.85) and had lower standard deviation (s = 0.02 to 0.05) than resistive index from interlobar arteries (r = 0.48, 0.54, 0.61) (s = 0.03 to 0.11). In two animals the difference was significant (correlation: P < or = 0.01, P = 0.13, P < or = 0.05; standard deviation: P < or = 0.01, P < or = 0.34, P < or = 0.05). For detecting renal artery stenosis, vessels within the renal sinus should be used for Doppler sampling.

Quantification of pleural effusions: sonography versus radiography.

PURPOSE: To develop a practical method of estimating the volume of pleural effusions with sonography. MATERIALS AND METHODS: Fifty-one patients underwent sonography of the pleural space while supine. Sonographic results and results of lateral decubitus radiography were compared with actual effusion volumes. The maximum thickness of the pleural fluid layer was measured with both modalities, while actual effusion volume was determined by means of complete drainage. RESULTS: Sonographic measurements correlated statistically significantly better with actual effusion volume (r = .80) than did radiographic measurements (r = .58) (P < or = .05). With sonographic measurement, an effusion width of 20 mm had a mean volume of 380 mL +/- 130 (standard deviation), while one of 40 mm had a mean volume of 1,000 mL +/- 330. Prediction error with sonographic measurement (mean, 224 mL) was statistically significantly less (P < or = .002) than that with radiographic measurement (mean, 465 mL). CONCLUSION: In quantification of pleural effusions, the sonographic measurement method presented is preferable to radiographic measurement.

[Rate of thrombosis after cava filter implantation. Long-term results]. / Thromboserate nach Kavafilterimplantation. Langzeitergebnisse.

Thrombosis of the access site and occlusion of the inferior vena cava after placement of an inferior vena caval filter are known complications of caval interruption. 30 patients were evaluated with colour-coded Doppler sonography 4 to 66 months (average 2.5 years) after percutaneous placement of either a Günther filter, a Bird's Nest filter or a Simon-Nitinol filter. One right internal jugular vein had post-thrombotic alterations. One inferior vena cava was found to be occluded 15 months after Simon-Nitinol filter placement. The long-term occlusion rates of access site and inferior vena cava after percutaneous filter introduction are low. These two factors need not be considered if implantation of a caval filter is contemplated.

Ultrasound-guided supraclavicular approach for regional anesthesia of the brachial plexus.

We prospectively studied 40 patients (ASA grades I-III) undergoing surgery of the forearm and hand, to investigate the use of ultrasonic cannula guidance for supraclavicular brachial plexus block and its effect on success rate and frequency of complications. Patients were randomized into Group S (supraclavicular paravascular approach; n = 20) and Group A (axillary approach; n = 20). Ultrasonographic study of the plexus sheath was done. After visualization of the anatomy, the plexus sheath was penetrated using a 24-gauge cannula. Plexus block was performed using 30 mL bupivacaine 0.5%. Onset of sensory and motor block of the radial, ulnar, and median nerves was recorded in 10-min intervals for 1 h. Satisfactory surgical anesthesia was attained in 95% of both groups. In Group A, 25% showed an incomplete sensory block of the musculocutaneous nerve, whereas all patients in Group S had a block of this nerve. Complete sensory block of the radial, median, and ulnar nerves was attained after an average of 40 min without a significant difference between the two groups. Because of the direct ultrasonic view of the cervical pleura, we had no cases of pneumothorax. An accidental puncture of subclavian or axillary vessels, as well as neurologic damage, was avoided in all cases. An ultrasonography-guided approach for supraclavicular block combines the safety of axillary block with the larger extent of block of the supraclavicular approach.

Determination of optimal time window for liver scanning with CT during arterial portography.

PURPOSE: To determine the optimal time window for scanning the liver with computed tomography (CT) during arterial portography (CTAP). MATERIALS AND METHODS: After vasodilation and contrast medium injection into the superior mesenteric artery (80 mL at 5 mL/sec), 25 repeated scans were obtained at a single level within 83 seconds in 13 patients. Attenuation was measured on every scan, and time-attenuation curves were created. Enhancement characteristics of the portal vein, liver parenchyma, aorta, and tumors were evaluated. RESULTS: Parenchymal enhancement of more than 60 HU was achieved between 18 seconds +/- 4 (standard deviation) and 67 seconds +/- 15, and high parenchyma-to-tumor contrast of more than 50 HU occurred between 18 seconds +/- 3 and 62 seconds +/- 14. CONCLUSION: To scan the liver within such a narrow time window, a spiral CT technique is necessary. When the above injection parameters are used in CTAP, the spiral CT sequence should be started 20 seconds after the beginning of the injection.