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991.

Purpose

Desmoplastic fibromas are primary bone tumors that seldom occur in the cranial bones. Furthermore, reports of desmoplastic fibromas of the skull in children are exceedingly rare. Although desmoplastic fibromas are histologically benign, they are locally aggressive and have a propensity to reoccur. Their radiographic appearance may mimic other more common central nervous system and bone neoplasms. There are only 19 reported cases of desmoplastic fibroma of the cranium in the literature, and only seven occurred in the pediatric age group. We present a case report of an 11-year-old female patient with a desmoplastic fibroma of the parieto-occipital region and review the literature.

Case report

An 11-year-old female presented to the craniofacial clinic complaining of intermittent pain and a soft mass in the occipital region. There was a distant history of trauma to the region that did not require medical intervention. Computed tomography imaging revealed a lytic bone lesion overlying the sagittal sinus in the parieto-occipital region. Surgical resection with wide margins and immediate autologous reconstruction was performed. Pathological analysis revealed a desmoplastic fibroma. At 4 months of follow-up, no recurrence has been noted.

Conclusion

Desmoplastic fibroma of the cranium is rare. Complete surgical resection with careful follow-up is the treatment of choice.  相似文献   
992.
993.

Objective

The study examined differences in the recurrence rate of primary intracerebral hemorrhage (P-ICH) according to anti-hypertensive drug (AHD) use by patients with hypertension.

Methods

This prospective, longitudinal cohort study was performed on 2384 patients diagnosed with supratentorial P-ICH and hypertension in the stroke unit of a single-center. During follow-up (mean, 44.9 ± 31.5 months), investigators interviewed subjects or caregivers by telephone or examined patients every 3–6 months. Target blood pressure was <140/90 mmHg in the P-ICH cohort with hypertension.

Results

Of 1317 P-ICH patients defined to be taking AHDs, P-ICH recurrence occurred in 129 (9.8%). 1211 patients (92.0%) reached target blood pressure. In multivariate regression analysis, advanced age (≥70 years), poor functional outcome after first P-ICH, lobar location of P-ICH, previous history of cerebral ischemia, diuretic monotherapy and α- or β-blocker monotherapy were associated with risk of recurrence.

Conclusions

Although hypertension is the most important factor for preventing P-ICH recurrence, we found that, even in the presence of optimal anti-hypertensive medication, recurrent P-ICH attack can occur. Therefore, management of other risk factors of recurrent P-ICH, such as modification of lifestyle, must be considered in treating the P-ICH patients.  相似文献   
994.
995.
996.

Objective

Although it is hypothesized that inflammatory signals and/or hemodynamic stress resulting from carotid disease increase the risk of aneurysm formation and growth, a relationship between intracranial aneurysms and extracranial carotid artery disease (ECAD) has not been explored. Here, we examined the characteristics of intracranial aneurysms associated with ECAD.

Methods

A total of 606 consecutive patients with stenosis of 50% or more of the proximal internal carotid artery (pICA) were enrolled. Stenosis was identified by conventional angiography between January 2003 and December 2009. We determined the prevalence of intracranial aneurysms in this population. The characteristics of the aneurysms were analyzed according to the degree and laterality of stenosis. The changes in the aneurysms were tracked for the evaluation of stability.

Results

In 86 patients (14.2%), 120 aneurysms were detected in association with pICA stenosis. In this group, 97 were associated with unilateral pICA stenosis. The distribution of aneurysms was independent of the laterality of stenosis, but aneurysms were more prevalent in the contralateral side as the stenosis grade increased (P < 0.001). All aneurysms with an imaging follow-up (28.9 ± 14.3 months) were stable, and the course was not affected by treatment of the carotid stenosis. In 23 aneurysms associated with bilateral pICA stenosis, there was only one case that increased in size during a 41-month period.

Conclusion

Intracranial aneurysms were most likely associated with ECAD, but were evenly distributed irrespective of the laterality of the stenosis. The distribution was related to the severity of the contralateral pICA stenosis. The low incidence of aneurysm growth or rupture in patients with significant ECAD indicates that these aneurysms do not require immediate intervention more than other conditions.  相似文献   
997.
Infective endocarditis represents a classical contra-indication to thrombolysis for acute ischemic stroke due to a potential increased risk of intracranial hemorrhage. However, some case reports have suggested safety and potential efficacy of intravenous or intra-arterial thrombolysis in stroke related to infective endocarditis. We present a case of ischemic stroke related to infective endocarditis who was treated with intravenous tissue plasminogen activator within the first 3 h of symptoms onset and subsequently developed symptomatic multifocal intracerebral hemorrhages, and summarize currently available data on this issue.  相似文献   
998.
999.
1000.
During brain development, many factors influence the assembly and final positioning of cortical neurons, and this process is essential for proper circuit formation and normal brain function. Among many important extrinsic factors that guide the maturation of embryonic cortical neurons, the secreted neurotransmitter GABA has been proposed to influence both their migratory behaviour and their terminal differentiation. The full extent of the short‐term and long‐term changes in brain patterning and function caused by modulators of the GABA system is not known. In this study, we specifically investigated whether diazepam, a commonly used benzodiazepine that modulates the GABAA receptor, alters neuronal positioning in vivo, and whether this can lead to lasting effects on brain function. We found that fetal exposure to diazepam did not change cell positioning within the embryonic day (E)14.5 mouse cerebral cortex, but significantly altered neuron positioning within the E18.5 cortex. In adult mice, diazepam treatment affected the distribution of cortical interneurons that express parvalbumin or calretinin, and also led to a decrease in the numbers of calretinin‐expressing interneurons. In addition, we observed that neonatal exposure to diazepam altered the sensitivity of mice to a proconvulsant challenge. Therefore, exposure of the fetal brain to benzodiazepines has consequences for the positioning of neurons and cortical network excitability.  相似文献   
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