Magnetic resonance imaging patterns of the development of the sphenoid sinus: a review of 800 patients.

Accurate knowledge of age-related development and pneumatisation of the paranasal sinuses has become an important issue in diagnosing paranasal sinus diseases in infants and young adults. Magnetic resonance imaging (MRI) has the potential to assess bone marrow conversion and pneumatisation of the paranasal sinuses. We retrospectively reviewed 800 children aged 0-14 years undergoing brain MRI for various indications. T1-weighted sagittal and T2-weighted axial scans were evaluated for bone marrow conversion and development of pneumatisation of the sphenoid sinus. The sphenoid sinus had a uniformly low signal intensity on T1-weighted images in all children less than four months old. Signal intensity began to change to hyperintense marrow at the age of four months. Onset of pneumatisation was observed in 19% at the age of 12-15 months. Pneumatisation was complete in all patients older than 10 years. In conclusion, these data can be used as baseline standards of normal age-related development of the sphenoid sinus and can be of great value for the diagnostic and therapeutic management of pathologic conditions of the child's sphenoid sinus and its surrounds.     

Decompressive craniectomy, reperfusion, or a combination for early treatment of acute "malignant" cerebral hemispheric stroke in rats? Potential mechanisms studied by MRI.

BACKGROUND AND PURPOSE: Both early reperfusion and decompressive craniectomy have proved beneficial in the treatment of large space-occupying "malignant" hemispheric stroke. The aim of this study was to directly compare the benefit of reperfusion with that of craniectomy and to study the effects of combined treatment in a rat model of focal cerebral ischemia. METHODS: Cerebral ischemia was introduced in 28 rats. Four groups were investigated: (1) no treatment, (2) decompressive craniectomy, (3) reperfusion, and (4) reperfusion and craniectomy as treatment at 1 hour after middle cerebral artery occlusion. Perfusion- and diffusion-weighted MRI were performed serially from 0.5 to 6 hours after middle cerebral artery occlusion. RESULTS: The 6-hour DWI-derived hemispheric lesion volumes in the reperfusion group (10.2+/-3.9%), the craniectomy group (23.0+/-6.4%), and the combination group (21.8+/-12.4) were significantly smaller than that in the control group (44.1+/-5.4%) (P<0.05). Reperfusion, craniectomy, and combined treatment led to higher perfusion in the cortex compared with the control group, whereas only reperfused animals achieved significantly higher perfusion in the basal ganglia. In 5 animals, combined reperfusion and decompressive craniectomy resulted in an early contrast media enhancement. CONCLUSIONS: Early reperfusion and craniectomy were shown to be effective in decreasing infarction volume by improving cerebral perfusion. Reperfusion remains the best therapy in malignant hemispheric stroke. Combined treatment yields no additional benefit compared with single treatment, probably because of early blood-brain barrier breakdown.     

Clinical outcome and neuropsychological deficits after right decompressive hemicraniectomy in MCA infarction

BACKGROUND AND PURPOSE: The purpose of this study was to analyse in detail the functional outcome and the neuropsychological deficits in patients with space-occupying infarction of the non-dominant hemisphere one year after surgery. METHODS: Postoperative complications and retrospective consent to surgery were assessed in a semi-structured interview in 26 patients. Functional outcome was measured with the Barthel-Index (BI) and Rankin-Scale. Neuropsychological tests in 14 patients focused on visuo-spatial and visuo-constructive abilities, attention, spatial span and self-rated mood. RESULTS: The one-year survival rate was 69 % (18 of 26). The functional outcome was good (BI >/= 90) in 3 patients, fairly good (BI 75-85) in 6, moderate (BI 30-70) in 6, and poor (BI 0-25) in 3 patients. Age was an independent predictor of outcome, patients above 52 years had a BI of 50 or below. Neuropsychological tests (14 of 18) showed profound attention deficits in all patients, and visuo-spatial and visuo-constructive deficits in patients with lower formal education. Retrospectively, 4 of 18 patients would not give consent to surgery again, mostly because of the bad quality of life postoperatively. CONCLUSION: Older patients do not seem to benefit from decompressive hemicraniectomy; more than half of the surviving younger patients have a good outcome and live independently. Attention deficits are prominent in all patients; visuo-spatial and constructive deficits are less pronounced in patients with higher formal education. Retrospective agreement to decompressive hemicraniectomy is high in patients with good functional outcome.     

Perfusion- and diffusion-weighted magnetic resonance imaging for monitoring decompressive craniectomy in animals with experimental hemispheric stroke

OBJECT: The aim of this study was to use two types of serial magnetic resonance (MR) imaging-perfusion-weighted (PW) and diffusion-weighted (DW)-to monitor craniectomy in rats with hemispheric stroke. METHODS: Focal cerebral ischemia was induced in 36 rats by using an endovascular method of occlusion of the middle cerebral artery (MCAO). Craniectomy was performed 4 or 24 hours later in 12 animals each. Twelve control animals underwent occlusion but did not receive treatment. Perfusion-weighted, DW, and T2-weighted MR images were obtained at 4, 24, 48, 72, and 168 hours postocclusion in all animals. Relative regional cerebral blood volumes and apparent diffusion coefficients (ADCs) were calculated for the cortex and basal ganglia. Hemispheric lesion volumes (expressed as percentages of total brain volumes; %HLV) as they appeared on DW and T2-weighted MR images and on histological slices stained with 2,3,5-triphenyltetrazolium chloride were compared. Neurological performances and infarct volumes measured 7 days postocclusion were used as study end points. Both PW and DW images demonstrated ischemic tissue 4 hours after MCAO in all animals. Early treatment by performing craniectomy significantly improved cortical perfusion (p < 0.01), whereas the same procedure conveyed no benefit to the basal ganglia. Compared with findings in control animals, the DW image-derived %HLV was significantly reduced (p < 0.01) and the cortical ADCs at 4 and 24 hours postocclusion were significantly higher in animals treated early (p < 0.05). Late treatment with craniectomy did not significantly affect cerebral perfusion. The correlation between the DW imaging-derived %HLV and the histologically derived %HLV at 4 to 72 hours postocclusion was good (r = 0.74), whereas at Day 7 postocclusion the %HLV was underestimated up to 41% on DW imaging. At 4 hours postocclusion T-weighted imaging failed to demonstrate the ischemic lesion, whereas from 24 to 72 hours postocclusion the correlation between the T2-weighted imaging-derived %HLV and the histologically derived %HLV was good (r > 0.81). Neurological performance was significantly improved in animals treated using craniectomy. CONCLUSIONS: Early craniectomy significantly improves cortical perfusion through leptomeningeal collateral vessels, significantly reduces infarct size, and improves neurological performance in animals with experimental acute hemispheric infarction. Both PW and DW imaging are suitable for noninvasive monitoring of the effects of decompressive craniectomy.     

Mast cells in pulmonary haemosiderosis

A case of childhood pulmonary haemosiderosis with a fourfold increase in mast cells in the lung is described. This finding is discussed in relation to the pathogenesis of the disease. Comparison is made with controls, and the use of disodium cromoglycate is advocated.     

International multidisciplinary collaboration toward an annotated definition of arthrogryposis multiplex congenita

Arthrogryposis multiplex congenita (AMC) has been described and defined in thousands of articles, but the terminology used has been inconsistent in clinical and research communities. A definition of AMC was recently developed using a modified Delphi consensus method involving 25 experts in the field of AMC from 8 countries. Participants included health care professionals, researchers, and individuals with AMC. An annotation of the definition provides more in‐depth explanations of the different sentences of the AMC definition and is useful to complement the proposed definition. The aim of this study was to provide an annotation of the proposed consensus‐based AMC definition. For the annotation process, 17 experts in AMC representing 10 disciplines across 7 countries participated. A paragraph was developed for each sentence of the definition using an iterative process involving multiple authors with varied and complementary expertise, ensuring all points of view were taken into consideration. The annotated definition provides an overview of the different topics related to AMC and is intended for all stakeholders, including youth and adults with AMC, their families, and clinicians and researchers, with the hopes of unifying the understanding of AMC in the international community.