Causal relationships between substance use and insomnia.

Background: Poor sleep quality and insomnia have been associated with the use of tobacco, alcohol, and cannabis, but it is unclear if there is a causal link. In this Mendelian Randomization (MR) study we examine if insomnia causes substance use and/or if substance use causes insomnia.

Methods: MR uses summary effect estimates from a genome-wide association study (GWAS) to create a genetic instrumental variable for a proposed 'exposure' variable and then identifies that same genetic instrument in an 'outcome' GWAS.

Interobserver variability among radiologists for diagnosis of scaphoid fractures by computed tomography.

Purpose: To determine the interobserver variability among radiologists for computed tomography (CT) diagnosis of scaphoid fractures.

Methods: Four specialized musculoskeletal radiologists evaluated the CT scans of 150 consecutive patients who were clinically suspected of having sustained a scaphoid fracture but whose scaphoid-specific radiographs were normal. The radiologists were asked to determine the presence or absence of a scaphoid fracture and to localize the fracture.

MRI as a reference standard for suspected scaphoid fractures.

Objectives: Some have suggested that MRI might be the best reference standard for a true fracture among patients with suspected scaphoid fractures. The primary aim of this study was to determine the rate of false-positive diagnosis of an acute scaphoid fracture in a cohort of healthy volunteers.

Methods: In a prospective study, 33 healthy volunteers were recruited and both wrists of each were scanned, except for 2 volunteers for whom only one wrist was scanned.

Early computed tomography compared with bone scintigraphy in suspected scaphoid fractures.

Purpose: This study examined whether multidetector computed tomography (CT) is superior to bone scintigraphy for diagnosis of an occult scaphoid fracture.

Methods And Materials: In a study period of 22 months, 100 consecutive patients with a clinically suspected scaphoid fracture and no fracture on scaphoid radiographs, were evaluated with CT within 24 hours after injury and bone scintigraphy between 3 and 5 days after injury. The reference standard for a true (radiographic occult) scaphoid fracture was either (1) diagnosis of fracture on both CT and bone scintigraphy or (2) in case of discrepancy, clinical and/or radiographic evidence of a fracture during follow-up.

A simple MRI protocol in patients with clinically suspected appendicitis: results in 138 patients and effect on outcome of appendectomy.

To establish the value of breathhold magnetic resonance imaging (MRI) in the diagnosis of acute appendicitis. Over a 14-month period, 138 patients clinically suspected of having appendicitis were evaluated prospectively with MRI and comprised the study group. Fast turbo spin-echo breathhold T1, T2 and T2 fat suppression sequences were used in coronal and axial planes.

Imaging of patients with clinically suspected appendicitis in the Netherlands: conclusions of a survey.

The aim of this study was to summarize the extent of variation in imaging strategies in patients clinically suspected of having appendicitis. By means of a written survey, the policies for the imaging management of patients clinically suspected of having appendicitis in the Netherlands were inventoried. A questionnaire was sent to the departments of surgery and radiology of all 105 Dutch hospitals, including the 8 academic medical centres, in March 2006.

Observer variation in MRI for suspected scaphoid fractures.

The aim of this study was to evaluate prospectively the observer variation in the detection of pathology on MRI for suspected acute scaphoid fracture. 79 consecutive MR scans were included to calculate the inter-observer variation. All patients were suspected of having a scaphoid fracture but had no fracture on radiographs.

Early magnetic resonance imaging compared with bone scintigraphy in suspected scaphoid fractures.

We evaluated 100 consecutive patients with a suspected scaphoid fracture but without evidence of a fracture on plain radiographs using MRI within 24 hours of injury, and bone scintigraphy three to five days after injury. The reference standard for a true radiologically-occult scaphoid fracture was either a diagnosis of fracture on both MRI and bone scintigraphy, or, in the case of discrepancy, clinical and/or radiological evidence of a fracture. MRI revealed 16 scaphoid and 24 other fractures.

Troponin I in predicting cardiac or pulmonary complications and outcome in subarachnoid haemorrhage.

Background: Patients with aneurysmal subarachnoid haemorrhage (SAH) are at risk of cardiac and pulmonary complications. Troponin I (cTnI), a reliable marker of myocardial injury, is frequently raised after SAH.

Aims: To investigate the additional value of (cTnI) in predicting cardiac or pulmonary complications and outcome in patients with SAH.

[Diagnostic image (187) A teenager in shock three weeks after a gunshot injury. Bleeding from a delayed renal artery pseudoaneurysm].

A 15-year-old boy was hospitalised because of injuries caused by a gunshot. After three weeks shock developed due to bleeding from a renal artery pseudoaneurysm.

The pathogenesis of cysts accompanying intra-axial primary and metastatic tumors of the central nervous system.

Recent reports have suggested that cyst formation accompanying astrocytomas in the central nervous system (CNS) is due to an edematous process caused by blood-brain barrier (BBB) disruption and not a result of necrosis. This study is performed to investigate whether the hypothesis of cyst formation based on BBB disruption also applies to various pathologically different intra-axial gliomatous tumors and metastases. By chemical analysis, using immunokinetic nephelometry, isoelectric focussing, cellulose acetate electrophoresis and a biuretic method, the concentrations of albumin, immunoglobulin G (IgG), IgA, alpha2-macroglobulin, IgM and total protein were measured and proportions of concentrations of these proteins were compared in cyst fluid, blood plasma and cerebrospinal fluid (CSF).

Cystic lesions accompanying extra-axial tumours.

We examined the mechanism of cyst formation in extra-axial tumours in the central nervous system (CNS). Cyst fluid, cerebrospinal fluid (CSF) and blood plasma were analysed in eight patients with nine peritumoral cysts: four with meningiomas, two with intracranial and two spinal intradural schwannomas. Measuring concentrations of various proteins [albumin, immunoglobulin G (IgG), IgA, alpha 2-macroglobulin and IgM] in cyst fluid, CSF and blood plasma provides insight into the state of the semipermeability of the blood-brain barrier (BBB) and blood-cerebrospinal fluid barrier.

Analysis of fluid in cysts accompanying various primary and metastatic brain tumours: proteins, lactate and pH.

There is a growing interest in cystic lesions of the brain. By examining the cyst content of brain tumours more insight into the pathogenesis of cyst formation has been found. In this study, 39 samples of cyst fluid of 34 patients with a cyst accompanying a brain tumour were collected and studied biochemically regarding their protein content, lactate and pH.

Radiographic loosening of cementless threaded acetabular cups. No additional diagnostic value of arthrography in 30 patients.

We compared arthrography with plain radiographs in 30 consecutive patients having a clinical diagnosis of loosening of a smooth-threaded acetabular prosthesis (Mecron, Berlin). Leakage of contrast at the interface between the ring and the bone on the medial side of the prosthesis was seen in 21 patients. Loosening of the cup was also visible on the plane radiographs and loosening was confirmed in all these patients at revision surgery.

Radiographic evaluation of developing instability of the Mecron cementless, threaded acetabular prostheses.

Purpose: To evaluate radiographically the history of the Mecron acetabular prosthesis.

Material And Methods: The pelvic radiographs of 350 consecutive patients with a smooth threaded acetabular prosthesis type Mecron were retrospectively evaluated (follow-up 1 to 6 years, mean 4 years). A demarcation zone seen at the medial side of the prosthesis was graded from 0 (absent) to 3 (severe).

Results of 75 consecutive patients with an acetabular fracture.

From 1988 to 1991, 75 consecutive patients with an acetabular fracture were treated. Follow up was for a minimum of 2 years (average, 3 years; range, 2-5 years). Sixty five patients had a solitary acetabular fracture, and in 10 the acetabular fracture was associated with a pelvic fracture (52 men and 23 women; average age, 46 years; range, 17 to 99 years).

Reproducible radiographs of acetabular prostheses. A method assessed in 35 patients.

35 patients with a smooth, threaded acetabular Mecron type prosthesis were examined with the aid of a table top with wiremarkers and a fixed 30-degree wedge to allow for reproducible positioning. Under fluoroscopic control, pelvic and spot films were made. The inter- and intraobserver variability of anteversion and inclination angle measurements of the prostheses had a standard deviation of less than 1 degree.

Injuries of the lateral ankle ligaments: classification with tenography and arthrography.

To assess the value of tenography of the peroneal tendon sheaths and of arthrography of the tibiotalar joint for the diagnosis and classification of recent ruptures of the lateral ankle ligaments, the authors performed a prospective study on 108 patients with inversion trauma of the ankle. All patients underwent tenography. Arthrography was performed if results of tenography were negative.

Chest radiography in acute traumatic rupture of the thoracic aorta.

Of 123 patients who had suffered blunt trauma to the chest traumatic aortic rupture was eventually confirmed in 61 and absent in 62 patients. The chest radiographs of these patients were examined for 15 signs reported in the literature as being associated with traumatic aortic rupture. Although many individual signs were significantly more frequent in the aortic rupture group they were not useful in differentiating between patients with and those without rupture of the aorta.

Management of oesophageal perforations; a tailored approach.

The results of treatment of 20 oesophageal perforations were retrospectively studied in 19 consecutive patients. Most complications occurred after endoscopic procedures, after a delay in treatment of more than 12 hours, in patients with intrinsic oesophageal disease and in cases where only drainage procedures were possible. Because of the many factors that influence the outcome of the treatment of oesophageal perforation it is stressed that the therapeutic approach should not be dogmatic, but tailored to the individual patient.