Hibernoma--two patients with a rare lipoid soft-tissue tumour.

BACKGROUND: Hibernomas are rare benign soft-tissue tumours arising from brown fat tissue. Although imaging characteristics are not specific certain imaging features, common locations and patient demographics may suggest hibernoma as a differential diagnosis. CASE PRESENTATION: We report on two 48-year-old male patients with hibernoma. The tumour presented with local swelling of the inguinal region in the first patient and was an incidental imaging finding in the second patient. Imaging included magnetic resonance imaging in both patients and computed tomography as well as 18F-fluorodeoxyglucose positron emission tomography-computed tomography in the second patient. In both cases histological diagnosis was initially based on excisional and needle core biopsy, respectively. Complete surgical resection confirmed the diagnosis of hibernoma thereafter. CONCLUSION: In soft tissue tumours with fatty components hibernoma may be included into the differential diagnosis. Because of the risk of sampling errors in hibernoma-like tissue components of myxoid and well-differentiated liposarcoma, complete resection is mandatory. This article also reviews the current imaging literature of hibernomas.

[Congenital brain malformations]. / Angeborene Hirnfehlbildungen.

CLINICAL ISSUE: Malformations of the central nervous system belong to the most common developmental disorders in humans. The clinical presentation of brain malformations is nonspecific including developmental delay, hypotonia, and/or epilepsy. The great heterogeneity concerning etiology, mechanisms of development and morphology is challenging for diagnosis and classification of brain malformations. Thereby recognizing specific malformations is essential for optimal patient management and prognostic evaluation. The aim of this article is to give an overview of several clinically relevant brain malformations occurring from different disrupted developmental processes in brain formation. STANDARD RADIOLOGICAL METHODS: Several brain malformations are already diagnosed during routine ultrasound in pregnancy. However pre- and postnatal magnetic resonance imaging remains the gold standard in detecting the partially subtle changes and to classify the malformations. METHODICAL INNOVATIONS: Advances in pre- and postnatal neuroimaging techniques and increasing investigation of genetic mechanisms underlying brain formation and its abnormalities have led to a better understanding of embryologic development and pathogeneses of brain malformations. CONCLUSION: Besides patient's history and clinical phenotype, neuroimaging plays a key role in diagnosis. Not always a specific diagnosis can be made, but neuroimaging patterns often enable a focused genetic testing and therefore are revolutionary for etiologic and prognostic assignment. Basic knowledge of brain development facilitates understanding and classifying of structural brain abnormalities.

Case of functional paraganglioma with intraoperative hypertensive crisis during robot-assisted thoracoscopic resection.

BACKGROUND: Mediastinal paragangliomas are rare. Their dangerousness may unfold during surgery, especially if hormonal activity was previously unknown. We report our experience with this case in context to the incidence and localization of atypically located mediastinal paragangliomas in the literature. CASE PRESENTATION: A 69-year-old female patient who was scheduled for thoracoscopic resection due to a posterior mediastinal tumor that had been progressing in size for several years and increasing symptoms. The induction of anesthesia, the ventilation of the lungs and the gas exchange after lung separation was uneventful. After initially stable circulatory conditions, there was a sudden increase in blood pressure up to 300/130 mmHg and tachycardia up to 130/min. This hypertensive phase was difficult to influence and required a rapid and consistent use of antihypertensive medication to bring down the blood pressure to reasonable values. The patient stabilized after tumor resection. The postoperative course was unremarkable. During the intraoperative blood pressure crisis, blood was drawn for analysis. These samples showed elevated concentrations of normetanephrine and metanephrine. The tumor subsequently presented as a catecholamine-secreting paraganglioma. CONCLUSION: In order to avoid life-threatening blood pressure crises, hormone activity should be ruled out preoperatively in the case of mediastinal tumor, in which a paraganglioma could be considered in the differential diagnosis, especially if there are indications of hypertension in the medical history. Robotic-assisted thoracoscopic resection of the posterior mediastinal tumor was a feasible surgical method, even in the case of unexpected functional paraganglioma.

Influence of Anatomic Conditions on Efficacy and Safety of Combined Intermediate Cervical Plexus Block and Perivascular Infiltration of Internal Carotid Artery in Carotid Endarterectomy: A Prospective Observational Trial.

Ultrasound-guided intermediate cervical plexus blockade with perivascular infiltration of the carotid artery bifurcation perivacular block (PVB) is a reliable technique for regional anesthesia in carotid endarterectomy (CEA). We investigated the effect of the carotid bifurcation level (CBL) on PVB efficacy and safety in patients undergoing CEA. This prospective observational cohort study included 447 consecutive CEA patients who received PVB over a 6-y period. Vascular and neurologic puncture-related complications were recorded. The CBL was localized at the low level (C4 and C5 vertebra, low-level [LL] group) in 381 (85.2%) patients and at the high level (C2 and C3 vertebra, high-level [HL] group) in 66 (14.8%) patients. Local anesthetic supplementation by surgeons was necessary in 64 (14.3%) patients in the LL group and 38 (59.4%) patients in the HL group (p < 0.001) and was associated with a higher rate of central neurologic complications in the HL group (p = 0.031). Therefore, the efficacy of the PVB may be influenced by the CBL.

Severely impaired cerebrovascular reserve in patients with cerebral proliferative angiopathy.

OBJECT: Cerebral proliferative angiopathy (CPA) has been morphologically distinguished from classically appearing brain arteriovenous malformations (AVMs) by exhibition of functional brain parenchyma that is intermingled with abnormal vascular channels. The presence of oligemia in this intralesional brain tissue may suggest ischemia, which is not detected in classic brain AVMs. The authors hypothesized that patients with CPA would exhibit a greater impairment of cerebrovascular reserve in neuronal tissue surrounding the true nidus compared with those with brain AVMs. METHODS: Four patients with CPA, 10 patients with brain AVMs and seizures, and 12 young healthy individuals were studied. The 4 patients with CPA underwent blood oxygen level-dependent MR imaging examinations while applying normoxic step changes in end-tidal CO(2) to obtain quantitative cerebrovascular reactivity measurements. RESULTS: Patients with a CPA lesion exhibited severely impaired perilesional cerebrovascular reserve in comparison with patients with brain AVMs and seizures (0.10 ± 0.03 vs 0.16 ± 0.03, respectively; p < 0.05), and young healthy individuals (0.10 ± 0.03 vs 0.21 ± 0.06, respectively; p < 0.01). CONCLUSIONS: This study demonstrated severely impaired cerebrovascular reserve in the perilesional brain tissue surrounding the abnormal vessels of patients with CPA. This finding may provide an additional means to distinguish CPA from classic brain AVMs.

Distribution of regional lung aeration and perfusion during conventional and noisy pressure support ventilation in experimental lung injury.

In acute lung injury (ALI), pressure support ventilation (PSV) may improve oxygenation compared with pressure-controlled ventilation (PCV), and benefit from random variation of pressure support (noisy PSV). We investigated the effects of PCV, PSV, and noisy PSV on gas exchange as well as the distribution of lung aeration and perfusion in 12 pigs with ALI induced by saline lung lavage in supine position. After injury, animals were mechanically ventilated with PCV, PSV, and noisy PSV for 1 h/mode in random sequence. The driving pressure was set to a mean tidal volume of 6 ml/kg and positive end-expiratory pressure to 8 cmH2O in all modes. Functional variables were measured, and the distribution of lung aeration was determined by static and dynamic computed tomography (CT), whereas the distribution of pulmonary blood flow (PBF) was determined by intravenously administered fluorescent microspheres. PSV and noisy PSV improved oxygenation and reduced venous admixture compared with PCV. Mechanical ventilation with PSV and noisy PSV did not decrease nonaerated areas but led to a redistribution of PBF from dorsal to ventral lung regions and reduced tidal reaeration and hyperinflation compared with PCV. Noisy PSV further improved oxygenation and redistributed PBF from caudal to cranial lung regions compared with conventional PSV. We conclude that assisted ventilation with PSV and noisy PSV improves oxygenation compared with PCV through redistribution of PBF from dependent to nondependent zones without lung recruitment. Random variation of pressure support further redistributes PBF and improves oxygenation compared with conventional PSV.