Intraorbital Abducens Nerve Schwannoma

BACKGROUND: Schwannomas of the abducens nerve are extremely rare tumors. The tumor may be located within the cavernous sinus or more often at the prepontine region. However, literature research has identified only one case of isolated schwannoma of the orbit, arising from the terminal branches of the abducens nerve to the lateral rectus muscle. This is only the second report of an abducens nerve schwannoma located entirely intraconal. CASE DESCRIPTION: We report a case of an intraorbital abducens nerve schwannoma in a 42-year-old man with no signs of neurofibromatosis. The lesion resulted in progressive diplopia and focal abducens palsy. The clinical, radiologic, and pathologic features are presented. RESULTS: We point the particular aspects and discuss the possible treatments and approaches to preserve nerve function. CONCLUSIONS: Being a benign lesion, one of the goals has always been total removal. The knowledge of the correct anatomic features made us believe that the VI nerve function could be preserved. Our case is the first example of a total removal with eye abduction preserved. Because of that, we believe that it is reasonable to aim for these goals in future cases

Hermitian Yang-Mills instantons on resolutions of Calabi-Yau cones

We study the construction of Hermitian Yang-Mills instantons over resolutions of Calabi-Yau cones of arbitrary dimension. In particular, in d complex dimensions, we present an infinite family, parametrised by an integer k and a continuous modulus, of SU(d) instantons. A detailed study of their properties, including the computation of the instanton numbers is provided. We also explain how they can be used in the construction of heterotic non-Kahler compactifications.Comment: 20 pages, 1 figure; typos corrected, section 3.1 expande

Case Report: Rare Convexity Meningeal Chondroma Mimicking a Meningioma

Background: Intracranial chondromas account for 0.2-0.3% of all intracranial neoplastic lesions and less than a quarter arise in the convexity or falx. Despite its benign nature, exceedingly rare malignant transformations exist. The misdiagnosis with meningiomas is frequent and may be related with chondromas' similar insidious clinical presentation and imaging features. Standalone surgery is advised and complete resection provides the definitive treatment. Case description: A 44-year-old female presents with insidious headache, visual disturbances, and papilledema. The imaging studies were compatible with frontal parasagittal meningioma. Surgery revealed a meningeal based mass, mostly avascular and with a well-demarked surgical plane from the brain parenchyma. Complete resection with meningeal margins was achieved and the histopathologic examination revealed a chondroma. The patient symptoms subsided and no surgical complications existed. Conclusion: Intracranial convexity chondromas constitute a rare differential diagnosis for meningiomas. The present case reinforces the current scarce data and serves as reminder for clinicians diagnosing and treating intracranial tumors.info:eu-repo/semantics/publishedVersio

Methadone Intoxication in a Child: Toxic Encephalopathy?

Methadone is used in the treatment of opioid addiction. Acute intoxication can lead to severe consequences and can even be lethal. In several case reports and small series, a presumably toxic leukoencephalopathy is described resulting from inhalation of heroin. We present the case of a 3-year-old boy who ingested methadone accidentally. In a coma with acute obstructive hydrocephalus owing to massive cerebellar edema and supratentorial lesions, he was successfully treated with methylprednisolone and cerebrospinal fluid external drainage. To our knowledge, this is the first report of an encephalopathy associated with synthetic opioid intoxication

Pleuroamniotic shunting--case report

Fetal hydrothorax refers to a collection of fluid within the fetal thorax that may be the result of chylous leak from the thoracic duct (primary hydrothorax) or generalized fluid retention associated with immune or no immune fetal hydrops (secondary hydrothorax). The authors' presents a case report occurred in 2002, of a pregnant woman that at 25 weeks' gestation that was referred to Maternidade Bissaya-Barreto-Coimbra because of a fetal hydrothorax at left, under tension and with cardiac decompensation signs. A fetal thoracocentesis was performed and the diagnosis was chylothorax. Because of a rapid reaccumulation of fluid a pleuroamniotic shunt was placed. The effusion and the cardiac decompensation signs regressed. The delivery was at 38 weeks' gestation. The newborn had been stable. Actually he has 10 months, is healthy and has a normal grow and development

Instantons and Killing spinors

We investigate instantons on manifolds with Killing spinors and their cones. Examples of manifolds with Killing spinors include nearly Kaehler 6-manifolds, nearly parallel G_2-manifolds in dimension 7, Sasaki-Einstein manifolds, and 3-Sasakian manifolds. We construct a connection on the tangent bundle over these manifolds which solves the instanton equation, and also show that the instanton equation implies the Yang-Mills equation, despite the presence of torsion. We then construct instantons on the cones over these manifolds, and lift them to solutions of heterotic supergravity. Amongst our solutions are new instantons on even-dimensional Euclidean spaces, as well as the well-known BPST, quaternionic and octonionic instantons.Comment: 40 pages, 2 figures v2: author email addresses and affiliations adde

Soluble human Suppression of Tumorigenicity 2 is associated with endoscopic activity in patients with moderate-to-severe ulcerative colitis treated with golimumab

Suppressor of Tumorigenicity 2 (ST2) is an IL33 receptor detected in the mucosa and serum of ulcerative colitis (UC) patients. We evaluated soluble ST2 (sST2) as a surrogate biomarker of disease outcome and therapeutic response, in moderate-to-severe UC patients treated with golimumab.Agência financiadora Merck Sharp and Dohme, Lda, Portugal MK8259-22info:eu-repo/semantics/publishedVersio

Use of diffusion tensor imaging to assess the impact of normobaric hyperoxia within at-risk pericontusional tissue after traumatic brain injury

Ischemia and metabolic dysfunction remain important causes of neuronal loss after head injury, and we have shown that normobaric hyperoxia may rescue such metabolic compromise. This study examines the impact of hyperoxia within injured brain using diffusion tensor imaging (DTI). Fourteen patients underwent DTI at baseline and after 1 hour of 80% oxygen. Using the apparent diffusion coefficient (ADC) we assessed the impact of hyperoxia within contusions and a 1 cm border zone of normal appearing pericontusion, and within a rim of perilesional reduced ADC consistent with cytotoxic edema and metabolic compromise. Seven healthy volunteers underwent imaging at 21%, 60%, and 100% oxygen. In volunteers there was no ADC change with hyperoxia, and contusion and pericontusion ADC values were higher than volunteers (P < 0.01). There was no ADC change after hyperoxia within contusion, but an increase within pericontusion (P < 0.05). We identified a rim of perilesional cytotoxic edema in 13 patients, and hyperoxia resulted in an ADC increase towards normal (P=0.02). We demonstrate that hyperoxia may result in benefit within the perilesional rim of cytotoxic edema. Future studies should address whether a longer period of hyperoxia has a favorable impact on the evolution of tissue injury

Normobaric hyperoxia does not improve derangements in diffusion tensor imaging found distant from visible contusions following acute traumatic brain injury

We have previously shown that normobaric hyperoxia may benefit peri-lesional brain and white matter following traumatic brain injury (TBI). This study examined the impact of brief exposure to hyperoxia using diffusion tensor imaging (DTI) to identify axonal injury distant from contusions. Fourteen patients with acute moderate/severe TBI underwent baseline DTI and following one hour of 80% oxygen. Thirty-two controls underwent DTI, with 6 undergoing imaging following graded exposure to oxygen. Visible lesions were excluded and data compared with controls. We used the 99% prediction interval (PI) for zero change from historical control reproducibility measurements to demonstrate significant change following hyperoxia. Following hyperoxia DTI was unchanged in controls. In patients following hyperoxia, mean diffusivity (MD) was unchanged despite baseline values lower than controls (p < 0.05), and fractional anisotropy (FA) was lower within the left uncinate fasciculus, right caudate and occipital regions (p < 0.05). 16% of white and 14% of mixed cortical and grey matter patient regions showed FA decreases greater than the 99% PI for zero change. The mechanistic basis for some findings are unclear, but suggest that a short period of normobaric hyperoxia is not beneficial in this context. Confirmation following a longer period of hyperoxia is required.Dr. Veenith was supported by clinical research training fellowship from National institute of Academic Anaesthesia and Raymond Beverly Sackler studentship. VFJN is supported by a Health Foundation/Academy of Medical Sciences Clinician Scientist Fellowship. JPC was supported by Wellcome trust project grant. DKM is supported by an NIHR Senior Investigator Award. This work was supported by a Wellcome Trust Project Grant (WT093267) and Medical Research Council (UK) Program Grant (Acute brain injury: heterogeneity of mechanisms, therapeutic targets and outcome effects (G9439390 ID 65883)), the UK National Institute of Health Research Biomedical Research Centre at Cambridge, and the Technology Platform funding provided by the UK Department of Health. The funders had no role in study design, data collection and analyses, decision to publish, or preparation of the manuscript