Intraoperative magnetic resonance imaging-assisted transsphenoidal pituitary surgery in patients with acromegaly

In this largest study to date of GH-producing pituitary adenomas in which iMR imaging-guided transsphenoidal surgery was analyzed, the results suggest that this method is a highly effective and safe treatment modality, even compared with previously published surgical series in which high-field iMR imaging was used. Limitations of iMR imaging are the detection of small residual tumor in the cavernous sinus and persisting disease that could not be observed, even on diagnostic high-field follow-up MR images. This points to a general limitation regarding remission rates that can be achieved using iMR imaging. Nevertheless, iMR imaging led to an increase of the remission rate in this study

Extracranial-intracranial bypass in atherosclerotic cerebrovascular disease: Report of a single centre experience

Despite the failure of the international extracranial-intracranial (EC-IC) bypass study in showing the benefit of bypass procedure for prevention of stroke recurrence, it has been regarded to be beneficial in a subgroup of well-selected patients with haemodynamic impairment. This report includes the EC-IC bypass experience of a single centre over a period of 14 years. All consecutive 72 patients with atherosclerotic occlusive cerebrovascular lesions associated with haemodynamic compromise treated by EC-IC bypass surgery were retrospectively reviewed. Pre-operatively, 61% of patients presented with minor stroke and the remaining 39% with recurrent transient ischemic attacks (TIAs) despite maximal medical therapy. Angiography revealed a unilateral internal carotid artery (ICA) stenosis/occlusion in 79%, bilateral ICA stenosis/occlusion in 15%, MCA stenosis/occlusion in 3% and other multiple vessel stenosis/occlusion in 3% of the cases. H(2)(15)O positron emission tomography (PET) or 99mTc-HMPAO SPECT with acetazolamide challenge was performed for haemodynamic evaluation of the cerebral blood flow (CBF). All the patients had impaired haemodynamics pre-operatively in terms of reduced regional cerebrovascular reserve capacity and rCBF. Standard STA-MCA bypass procedure was performed in all patients. A total of 68 patients with 82 bypasses were reviewed with a mean follow-up period of 34 months. Stroke recurrence took place in 10 patients (15%) resulting in an annual stroke risk of 5%. Improved cerebral haemodynamics was documented in 81% of revascularised hemispheres. Patients with unchanged or worse haemodynamic parameters had significantly more post-operative TIAs or strokes when compared to those with improved perfusion reserves (30% vs.5% of patients, p<0.05). In conclusion, EC-IC bypass procedure in selected patients with occlusive cerebrovascular lesions associated with haemodynamic impairment has revealed to be effective for prevention of further cerebral ischemia, when compared with a stroke risk rate of 15% reported to date in patients only under antiplatelet agents or anticoagulant therapy

Acute recurrent haemorrhage of an intracranial meningioma

Meningioma-associated haemorrhages are rare. To our knowledge this is the first report of a patient with an acute two-stage haemorrhage of a benign intracranial meningioma (World Health Organization grade I) verified by cranial CT scan and histopathological examination. Early surgery with complete tumour removal led to a good outcome for the patient

Impact of intraoperative MRI-guided transsphenoidal surgery on endocrine function and hormone substitution therapy in patients with pituitary adenoma

BACKGROUND: Pituitary adenomas are rare with an incidence of 0.4-8.2 per 105 inhabitants. Symptoms range from headaches to pituitary insufficiency or excessive output of hormones with associated disease. Except for prolactinomas, surgery is recommended as the first line and most effective treatment for the majority of these tumours. One of the refinements of surgical therapy introduced was intraoperative magnetic resonance imaging (iMRI). OBJECTIVE: The aim of this study was to analyse the postoperative pituitary function and the general outcome of patients treated for non-functioning and GH-producing pituitary adenomas with a transsphenoidal iMRI-assisted approach using the PoleStar™ N20 imager. METHODS: A total of 148 consecutive iMRI-guided surgeries for GH-producing and non-functioning pituitary adenomas were retrospectively analysed. Patients' clinical data, endocrinological parameters, clinical examinations and pre-/post- and intraoperative imaging studies were evaluated. RESULTS: A total of 101 patients could be classified as being in remission at follow-up; 26 (17.6%) of them due to iMRI allowing additional tumour removal. A total of 44 patients (29.7%) had more complete tumour removal because remnants were detected by iMRI. The mean hormone levels of patients did not differ significantly between pre- and postoperative examinations. There were 62 patients with preoperative, and 43 patients with postoperative pituitary insufficiency, thus, due to surgery there were 19 (12.8%) patients with improved pituitary function. CONCLUSIONS: The results show this method to be a safe and effective treatment option increasing remission rate and keeping complication rate low. Postoperative pituitary function was preserved or improved - possibly due to more exact iMRI-assisted tumour removal

Pro-fibrotic phenotype of bone marrow stromal cells in Modic type 1 changes

Modic type 1 changes (MC1) are painful vertebral bone marrow lesions frequently found in patients suffering from chronic low-back pain. Marrow fibrosis is a hallmark of MC1. Bone marrow stromal cells (BMSCs) are key players in other fibrotic bone marrow pathologies, yet their role in MC1 is unknown. The present study aimed to characterise MC1 BMSCs and hypothesised a pro-fibrotic role of BMSCs in MC1. BMSCs were isolated from patients undergoing lumbar spinal fusion from MC1 and adjacent control vertebrae. Frequency of colony-forming unit fibroblast (CFU-F), expression of stem cell surface markers, differentiation capacity, transcriptome, matrix adhesion, cell contractility as well as expression of pro-collagen type I alpha 1, α-smooth muscle actin, integrins and focal adhesion kinase (FAK) were compared. More CFU-F and increased expression of C-X-C-motif-chemokine 12 were found in MC1 BMSCs, possibly indicating overrepresentation of a perisinusoidal BMSC population. RNA sequencing analysis showed enrichment in extracellular matrix proteins and fibrosis-related signalling genes. Increases in pro-collagen type I alpha 1 expression, cell adhesion, cell contractility and phosphorylation of FAK provided further evidence for their pro-fibrotic phenotype. Moreover, a leptin receptor high expressing (LEPRhigh) BMSC population was identified that differentiated under transforming growth factor beta 1 stimulation into myofibroblasts in MC1 but not in control BMSCs. In conclusion, pro-fibrotic changes in MC1 BMSCs and a LEPRhigh MC1 BMSC subpopulation susceptible to myofibroblast differentiation were found. Fibrosis is a hallmark of MC1 and a potential therapeutic target. A causal link between the pro-fibrotic phenotype and clinical characteristics needs to be demonstrated

Clinical associations and prognostic value of MRI-visible perivascular spaces in patients with ischemic stroke or TIA: a pooled analysis

BACKGROUND AND OBJECTIVES: Visible perivascular spaces are an MRI marker of cerebral small vessel disease and might predict future stroke. However, results from existing studies vary. We aimed to clarify this through a large collaborative multicenter analysis. METHODS: We pooled individual patient data from a consortium of prospective cohort studies. Participants had recent ischemic stroke or transient ischemic attack (TIA), underwent baseline MRI, and were followed up for ischemic stroke and symptomatic intracranial hemorrhage (ICH). Perivascular spaces in the basal ganglia (BGPVS) and perivascular spaces in the centrum semiovale (CSOPVS) were rated locally using a validated visual scale. We investigated clinical and radiologic associations cross-sectionally using multinomial logistic regression and prospective associations with ischemic stroke and ICH using Cox regression. RESULTS: We included 7,778 participants (mean age 70.6 years; 42.7% female) from 16 studies, followed up for a median of 1.44 years. Eighty ICH and 424 ischemic strokes occurred. BGPVS were associated with increasing age, hypertension, previous ischemic stroke, previous ICH, lacunes, cerebral microbleeds, and white matter hyperintensities. CSOPVS showed consistently weaker associations. Prospectively, after adjusting for potential confounders including cerebral microbleeds, increasing BGPVS burden was independently associated with future ischemic stroke (versus 0-10 BGPVS, 11-20 BGPVS: HR 1.19, 95% CI 0.93-1.53; 21+ BGPVS: HR 1.50, 95% CI 1.10-2.06; = 0.040). Higher BGPVS burden was associated with increased ICH risk in univariable analysis, but not in adjusted analyses. CSOPVS were not significantly associated with either outcome. DISCUSSION: In patients with ischemic stroke or TIA, increasing BGPVS burden is associated with more severe cerebral small vessel disease and higher ischemic stroke risk. Neither BGPVS nor CSOPVS were independently associated with future ICH

Impact of Cerebral Microbleeds in Stroke Patients with Atrial Fibrillation

OBJECTIVES: Cerebral microbleeds are associated with the risks of ischemic stroke and intracranial hemorrhage, causing clinical dilemmas for antithrombotic treatment decisions. We aimed to evaluate the risks of intracranial hemorrhage and ischemic stroke associated with microbleeds in patients with atrial fibrillation treated with Vitamin K antagonists, direct oral anticoagulants, antiplatelets, and combination therapy (i.e. concurrent oral anticoagulant and antiplatelet) METHODS: We included patients with documented atrial fibrillation from the pooled individual patient data analysis by the Microbleeds International Collaborative Network. Risks of subsequent intracranial hemorrhage and ischemic stroke were compared between patients with and without microbleeds, stratified by antithrombotic use. RESULTS: A total of 7,839 patients were included. The presence of microbleeds was associated with an increased relative risk of intracranial hemorrhage (aHR 2.74, 95% confidence interval 1.76 - 4.26) and ischemic stroke (aHR 1.29, 95% confidence interval 1.04 - 1.59). For the entire cohort, the absolute incidence of ischemic stroke was higher than intracranial hemorrhage regardless of microbleeds burden. However, for the subgroup of patients taking combination of anticoagulant and antiplatelet therapy, the absolute risk of intracranial hemorrhage exceeded that of ischemic stroke in those with 2-4 microbleeds (25 vs 12 per 1,000 patient-years) and ≥11 microbleeds (94 vs 48 per 1,000 patient-years). INTERPRETATION: Patients with atrial fibrillation and high burden of microbleeds receiving combination therapy have a tendency of higher rate of intracranial hemorrhage than ischemic stroke, with potential for net harm. Further studies are needed to help optimize stroke preventive strategies in this high-risk group. This article is protected by copyright. All rights reserved

Tc transfer from water to monogastric

Technetium-99 (T1/2 : 212 000 years) is derived from the fission of uranium-235 and produced more particularly by nuclear fuel reprocessing plants. We studied, during a chronic contamination by water, excretion, distribution and retention of 99Tc in rats as monogastric model. More than 85 % of ingested 99Tc is excreted by urine and feces, urinary way being dominant from the first week, to reach 72 % of total excretion at the end of the experiment (14 weeks). The thyroid and hair content increased until the end of the treatment. They represented respectively 0.1 and 16 % of the given dose, after 98 days of intake. The liver and the kidneys content reached a plateau between the 40th and the 56th days of the exposure period. There was no 99Tc in the muscle and the intestine

Study of blood free amino-acid variations in goats. The onset of lactation

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