Occupational skin diseases: actual state analysis of patient management pathways in 28 European countries.

BACKGROUND: Work-related skin diseases (WSD) are caused or worsened by a professional activity. Occupational skin diseases (OSD) need to fulfil additional legal criteria which differ from country to country. OSD range amongst the five most frequently notified occupational diseases (musculoskeletal diseases, neurologic diseases, lung diseases, diseases of the sensory organs, skin diseases) in Europe. OBJECTIVE: To retrieve information and compare the current state of national frameworks and pathways to manage patients with occupational skin disease with regard to prevention, diagnosis, treatment and rehabilitation in different European countries. METHODS: A questionnaire-based survey of the current situation regarding OSD patient management pathways was carried out with experts on occupational dermatology and/or occupational medicine from 28 European countries contributing to the European Cooperation in Science and Technology (COST) Action TD 1206 (StanDerm) (www.standerm.eu). RESULTS: Besides a national health service or a statutory health insurance, most European member states implemented a second insurance scheme specifically geared at occupational diseases [insurance against occupational risks (synonyms: insurance against work accidents and occupational injuries; statutory social accident insurance)]. Legal standards for the assessment of occupationally triggered diseases with a genetic background differ between different countries, however, in most European member states recognition as OSD is possible. In one-third of the countries UV light-induced tumours can be recognized as OSD under specific conditions. CONCLUSION: OSD definitions vary between European countries and are not directly comparable, which hampers comparisons between statistics collected in different countries. Awareness of this fact and further efforts for standardization are necessary.

Proximate ferromagnetic state in the Kitaev model material α-RuCl3.

α-RuCl3 is a major candidate for the realization of the Kitaev quantum spin liquid, but its zigzag antiferromagnetic order at low temperatures indicates deviations from the Kitaev model. We have quantified the spin Hamiltonian of α-RuCl3 by a resonant inelastic x-ray scattering study at the Ru L3 absorption edge. In the paramagnetic state, the quasi-elastic intensity of magnetic excitations has a broad maximum around the zone center without any local maxima at the zigzag magnetic Bragg wavevectors. This finding implies that the zigzag order is fragile and readily destabilized by competing ferromagnetic correlations. The classical ground state of the experimentally determined Hamiltonian is actually ferromagnetic. The zigzag state is stabilized by quantum fluctuations, leaving ferromagnetism - along with the Kitaev spin liquid - as energetically proximate metastable states. The three closely competing states and their collective excitations hold the key to the theoretical understanding of the unusual properties of α-RuCl3 in magnetic fields.

Safety and feasibility of intra-arterial nicardipine for the treatment of subarachnoid hemorrhage-associated vasospasm: initial clinical experience with high-dose infusions.

BACKGROUND AND PURPOSE: Delayed cerebral ischemia from vasospasm is a major complication after aneurysmal subarachnoid hemorrhage (SAH), but complications and/or low efficacy are associated with current therapy. We report our initial experience with intra-arterial use of a calcium channel blocker, nicardipine. MATERIALS AND METHODS: A retrospective review of a consecutive series of patients with clinical and angiographic vasospasm treated with intra-arterial nicardipine was performed. Standard criteria for definition of significant, intractable vasospasm after aneurysmal SAH were used. After catheter angiographic confirmation of vasospasm, arteries showing severe narrowing were targeted for superselective catheterization. Nicardipine was infused at a high dose rate (0.415-0.81 mg/min). Contrast injections were performed at 2-5-mg intervals to assess effective response (a 60% increase in arterial diameter of the most severely decreased in caliber vessel compared with the very first angiographic run). RESULTS: Eleven consecutive patients underwent a total of 20 procedures; most had SAH with high Hunt and Hess grades (III or IV). All had depressed level of consciousness; others had paresis (7/20, 35%), aphasia (1/20, 5%), and facial nerve palsy (1/20, 5%). Between 10 and 40 mg of nicardipine was used. A 60% increase in diameter of the main affected artery compared with the initial diameter measured in the initial angiographic run was achieved in all procedures. Clinical improvement (resolved focal symptoms or increased Glasgow Coma Score) occurred in 10 of 11 patients (91%). One patient died from complications of the initial hemorrhage. No complications occurred after 16 of 20 procedures (80%); minor complications without sequelae occurred after the remaining procedures. Follow-up of at least 2 months in 10 survivors revealed minor or no deficits in most patients with a Glasgow Outcome Score of 1 or 2 in 9 of 10 patients (90%). CONCLUSION: In this small series, high-dose intra-arterial nicardipine infusion to treat SAH-associated vasospasm seems to be safe and effective.

Rapidly progressive fatal bihemispheric infarction secondary to Moyamoya syndrome in association with Graves thyrotoxicosis.

Moyamoya syndrome is the secondary form of intracranial arterial occlusive diseases that produces collateral vessels from the base of brain. We report a case of Moyamoya syndrome developing in association with Graves thyrotoxicosis; as a result of its rapid progression and severe global ischemia, it was ultimately fatal. Because of the rarity of this association, we reviewed the literature in an attempt to establish possible demographic and clinical characteristics that may suggest putative mechanisms of pathogenesis.

In vitro studies of the neuroform microstent using transparent human intracranial arteries.

For better understanding of relevant morphology and mechanics, direct visualization of a Neuroform microstent (NFM) within an actual human intracranial artery is essential. Twelve NFM were deployed into 8 various segments of formaldehyde-fixed cadaver intracranial arteries. The arteries were then dehydrated and cleared in methyl salicylate to create transparency. The morphology of NFM was studied by digital macro-photography with a back illumination system. The possible limitations and important findings of the NFM were discussed.

Strong-field double ionization of rare gases.

We have studied the double ionization of helium and other rare gases using an electron-ion coincidence technique. With this scheme, the electron energy spectrum correlated to the creation of a doubly charged ion may be compiled. In all cases, the observed double ionization electron distributions are similar and enhanced at high energies, while the single ionization spectra exhibit distinct differences.

Technical feasibility and performance studies of a 0.009-inch nitinol microguidewire for potential neuroendovascular applications.

RATIONALE AND OBJECTIVES: The authors conduct technical feasibility and performance studies on a new 0.009-inch nitinol microguidewire for potential neuroendovascular applications. METHODS: In vivo microcatheterizations of brachiocephalic arteries were performed in four pigs using the 0.009-inch nitinol microguidewire with a commonly used microcatheter and compared with the performance of commercially available microguidewires. Vessels catheterized using the 0.009-inch wire were evaluated by histopathological analysis. A standardized, bench-top method of evaluating basic mechanical properties of microguidewires also was used to compare the 0.009-inch nitinol microguidewire with two commonly used microguidewires. RESULTS: The 0.009-inch microguidewire had similar steerability, tractability, torque control, and distal tip flexibility to the commonly used microguidewires in the in vivo simulations. Bench top testing showed the 0.009-inch microguidewire to have comparable distal tip flexibility and objective mechanical properties to the commonly used microguidewires. CONCLUSIONS: The comparable subjective and objective mechanical properties of the 0.009-inch nitinol microguidewire to that of commonly used microguidewires further establishes the possibility of clinical implementation.

Protein catabolism in growing Bacillus megaterium during adaptation to salt stress.

Elevated concentration of NaCl in liquid medium caused a concentration-dependent growth delay (adaptation lag) and decrease in the maximal growth rate of Bacillus megaterium. The adaptation to salt stress was accompanied by transformation of some otherwise stable (long-lived; LLP) cell proteins into quickly degraded (short-lived; SLP) ones. Exposure to the strongly growth-reducing 1 M NaCl increased the size of the SLP 'pool' of intracellular proteins from about 5 to about 15% of total protein. The major intracellular proteolytic capacity of B. megaterium is represented by intracellular serine proteinases (ISP). Paradoxically, their specific activity was lowered or masked during the adaptation phase marked by increased catabolism of short-lived and/or destabilized proteins by the stress. This documents that intracellular proteolytic activity cannot be a key regulator of protein catabolism during adaptation to stress.

Use of large-caliber coronary guiding catheters for neurointerventional applications.

The use of certain large-caliber (ie, 7F to 9F) coronary guiding catheters for selected neuroendovascular procedures is described in the context of surveying recently developed neurovascular guiding catheters. These large-caliber guiding catheters have proved useful in situations requiring proximal access to tortuous brachiocephalic arteries, permitting coaxial delivery of relatively large neurointerventional devices, such as most detachable balloons and 5F percutaneous transluminal angioplasty catheters. These large-caliber coronary guiding catheters have some important advantages over both old and new neurovascular guiding catheters, including favorably preshaped configurations and superior torque control. These features permit relatively easy direct selective catheterization of unfavorable vascular anatomy resulting from dolichoectasia of the aortic arch and great vessels.

Clinically aggressive diffuse capillary telangiectasia of the brain stem: a clinical radiologic-pathologic case study.

Capillary malformations or telangiectasias of the brain usually exhibit a benign clinical course, although occassionally they may be associated with mild to moderate symptomatology of uncertain origin. We report a case of an exceptionally aggressive capillary telangiectasia in a child, which was associated with progressive neurologic deterioration resulting in death.

An in vivo arteriovenous malformation model in swine: preliminary feasibility and natural history study.

PURPOSE: To assess the feasibility, natural history, and preliminary physiologic validation of creating an in vivo arteriovenous malformation model in swine. METHODS: A transorbital puncture technique into the cavernous sinus was used to create an arteriovenous communication between the rostral rete and the cavernous sinus in eight swine. Short-term patency and hemodynamic behavior were assessed clinically and by serial angiography. Acute phase physiologic characterization of four models was also performed, using intravascular pressure and Doppler blood flow velocity measurements. RESULTS: Large arteriovenous shunts between the rostral rete and cavernous sinus were consistently produced, which mimicked the angiographic features of cerebral arteriovenous malformations in humans. Classic changes in intraarterial and intravenous pressures and blood flow velocities were also observed. Early pathophysiologic evolution occurred in two animals, consisting of recruitment of previously unseen collateral vessels. Spontaneous occlusion of the arteriovenous shunt occurred in most animals within 7 days because of a rigorous fibroblastic response. CONCLUSIONS: A simple technique for creating an arteriovenous malformation model in swine is now possible and is promising for future studies.

Technical feasibility and histopathologic studies of ethylene vinyl copolymer (EVAL) using a swine endovascular embolization model.

PURPOSE: To study the safety, technical efficacy, and histopathology of the ethylene vinyl alcohol copolymer (EVAL) embolic mixture in an animal model. METHODS: Microcatheterization of the rete was performed in 29 swine. The clinical, angiographic, and histopathologic consequences of superselective injection of the two principal embolic mixture components (EVAL and dimethyl sulfoxide [DMSO]) were evaluated. Necropsy and standard histologic preparation were used for pathologic analysis. RESULTS: Significant technical difficulties and adverse outcomes occurred. The EVAL mixture was difficult to see under fluoroscopy and prematurely polymerized during one embolization, resulting in catheter occlusion. However, polymerized EVAL did not adhere to the catheter. DMSO damaged the plastic hubs of the microcatheters. Infusions of DMSO always caused immediate, moderate to severe vasospasm and frequently caused either subarachnoid hemorrhage or stroke. Histopathologic findings of both DMSO and DMSO plus EVAL were similar, producing variable endothelial denuding, thrombosis, and disruption of internal elastic lamina in the acute stage. An intense, mixed inflammatory response, organized thrombus, and transmural necrosis with extravasation were seen in the subacute and chronic stages. CONCLUSIONS: Despite having some desirable features as an embolic agent, significant problems were encountered with EVAL; the most important of which is that one of the principal components of the embolic mixture, DMSO, seems to be very angiotoxic.

Endovascular therapeutic approach to peripheral aneurysms of the superior cerebellar artery.

Peripheral aneurysms of the superior cerebellar artery may be difficult to treat surgically owing to their inaccessibility and to the frequent inability to preserve the involved parent artery. In fact, for most cases, surgical treatment consists of proximal parent artery occlusion and/or trapping with surgical clips. An equivalent endovascular therapeutic approach to these lesions may be an attractive alternative method of management. We describe two cases of peripheral superior cerebellar artery aneurysms that were treated successfully with endovascular embolization.

Pseudohemangioma of the vertebra: an unusual radiographic manifestation of primary Ewing's sarcoma.

Primary Ewing's sarcoma (ES) of the spine is uncommon, exhibiting a variety of appearances on plain-film radiographs and cross-sectional images. We report the unusual CT imaging manifestations of a primary ES with a coarse trabecular pattern that mimicked an aggressive hemangioma of the cervical spine.

Potential toxic effects of superselective injection of amobarbital sodium on microvasculature: a study in an animal model.

PURPOSE: To determine whether microvascular damage occurs from superselective intraarterial injection of amobarbital sodium using the swine endovascular embolization model. METHODS: Thirty-four swine underwent percutaneous femoral puncture for superselective catheterization of the proximal artery of the rete. Varying concentrations of amobarbital sodium were prepared (12.5 to 100 mg/mL solution) in either normal saline or sterile water (105 mOsm/L to 1138 mOsm/L) of which one concentration was infused slowly into one ipsilateral rete. Control infusions were also performed. Histopathologic changes were evaluated at 30 minutes and 10 days after infusion, using standard light and electron microscopy techniques. RESULTS: Moderate vasospasm occurred only in three swine at 100 mg/mL amobarbital sodium in normal saline. Light microscopy showed no significant histologic changes in the retia at any of the tested concentrations of amobarbital sodium. Electron microscopy showed ultrastructural alterations in the intima only at the higher amobarbital sodium concentrations. CONCLUSIONS: Concerns for inducing significant damage to cerebral microvasculature by superselective injection of amobarbital sodium at the usually recommended concentrations and doses are probably not justified.

Sentinel transoral hemorrhage from a pseudoaneurysm of the internal maxillary artery: a complication of CT-guided biopsy of the masticator space.

A patient presented with transoral hemorrhage 3 months after CT-guided percutaneous biopsy of the masticator space, prompting concern about sentinel hemorrhage from impending carotid artery rupture related to prior radical head and neck surgery and radiation therapy. Angiographic evaluation showed the internal carotid artery to be normal but demonstrated a pseudoaneurysm of the buccal branch of the internal maxillary artery exactly corresponding to the site of prior fine-needle biopsy.

A reexamination of the angiotoxicity of superselective injection of DMSO in the swine rete embolization model.

BACKGROUND AND PURPOSE: There are a variety of embolization applications for non-adhesive, liquid agents. We reevaluated the potential microvascular angiotoxicity of superselective infusions of dimethyl sulfoxide (DMSO) using very long infusion rates in a previously described animal model. METHODS: Twenty-six swine underwent percutaneous femoral puncture for superselective catheterization of the artery of the rete while being continuously monitored for ECG and intraarterial pressure. Two volumes (0.5 or 0.8 mL) and three durations (30, 60, and 90 seconds) of superselective infusion of DMSO were used to evaluate the effect of a single-dose rate within an ipsilateral rete. Contralateral control infusions of normal saline were also administered. Acute hemodynamic and angiographic outcomes were assessed. After recovery, follow-up angiography and sacrifice were performed at either 10 or 28 days. Brains and retia were harvested for gross and microscopic histopathologic evaluation. RESULTS: No significant hemodynamic alterations occurred acutely. Twenty-three of the 24 infused retia showed variable acute vasospasm that typically was mild to moderate in severity and transient (10 to 20 minutes). Follow-up angiography at sacrifice always showed normal retial arterial anatomy. No adverse clinical sequelae were noted. Gross inspection of brains showed no evidence of infarction or subarachnoid hemorrhage. Microscopic histopathologic examination of retia showed mostly nonspecific changes in both exposed and control samples. Possible causal histotoxicity was seen in four retia (three of four exposed to higher dose rates), in which involvement was limited to one to three retial arteries. CONCLUSION: Lower total dose and dose rates of superselective infusion of DMSO into the retial microarterial network resulted in substantially less angiotoxicity than that found in a previous study, as defined by clinical, angiographic, gross, and histopathologic criteria.

Endovascular therapy for the carotid blowout syndrome in head and neck surgical patients: diagnostic and managerial considerations.

PURPOSE: To review our institution's recent experience with patients with carotid blowout syndrome who were referred for emergency diagnostic angiography and endovascular therapy. METHODS: Eighteen consecutive patients who had had surgery for cancer of the head and neck and in whom carotid blowout syndrome had occurred were referred to our service in accordance with a standardized protocol. RESULTS: Twenty-three angiographic pathoetiologic conditions were diagnosed in the 18 patients; the majority of these were pseudoaneurysms involving various segments of the carotid system. Multiple lesions were detected in five patients. Most patients were treated by means of permanent balloon occlusion; in 8 patients with either multiple lesions or impending rupture requiring flap reconstruction, a composite permanent balloon occlusion of the affected carotid system was performed. Hyperacute hemorrhages were arrested in all cases. Hemorrhages reoccurred in 2 cases, and in 2 patients who had permanent balloon occlusion of the internal carotid artery, transient ischemic attacks occurred, which appeared to be related to temporary collateral reserve failure. No permanent neurologic complications ensued. CONCLUSION: Our recent experience with carotid blowout syndrome suggests that this clinical diagnosis represents a heterogeneous group of angiographic pathoetiologies that the physician should evaluate carefully before proceeding with endovascular therapy. Specific endovascular approaches depend on the pathoetiologic mechanism of active or impending hemorrhage and the urgency with which intervention is required.

Use of a Doppler guide wire for intravascular blood flow measurements: a validation study for potential neurologic endovascular applications.

PURPOSE: To conduct a validation study of a Doppler guide wire for potential neuroendovascular applications. METHODS: A 12-MHz, 0.018-inch Doppler guide wire was evaluated in eight swine under various blood flow conditions using two types of in vivo cerebrovascular models (physiologic and arteriovenous shunting). Flow conditions were mechanically and pharmacologically altered. Doppler average peak velocity was compared with volumetric blood flow, and flow profile corrections were calculated and analyzed. Qualitative aspects of the Doppler guide wire spectra were also assessed. RESULTS: Plots of average peak velocity versus volumetric blood flow showed excellent linear relationships (r2 > 0.94), which were maintained at high flow conditions (average peak velocity, 99 to 236 cm/sec; volumetric blood flow, 392 to 889 mL/min). Values of flow profile correction varied from 0.43 to 0.94 and showed no consistent relationship to changes in volumetric blood flow. CONCLUSIONS: The excellent correlation between average peak velocity and volumetric blood flow over a wide range of blood flow conditions and the additional qualitative information of the Doppler guide wire spectra establish a foundation for clinical implementation. The unpredictable variations of flow profile corrections remain obstacles for calculating volumetric blood flow based on Doppler guide wire average peak velocity.

Occult spontaneous lateral temporal meningoencephalocele: MR findings of a rare developmental anomaly.

We describe a case of an occult lateral temporal meningoencephalocele discovered in a 14-year-old boy during a work-up for minor head trauma. This spontaneous encephalocele resulted from a closure defect at the former sphenoidal fontanelle. Preoperative MR images are presented.