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Acute organophosphate (OP) intoxication is associated with many symptoms and clinical signs, including potentially life-threatening seizures and status epilepticus. Instead of being linked to the direct cholinergic toxidrome, OP-related seizures are more probably linked to the interaction of OPs with acetylcholineindependent neuromodulation pathways, such as GABA and NMDA. The importance of preventing, or recognizing and treating OP-related seizures lies in that, the central nervous system (CNS) damage from OP poisoning is thought to be due to the excitotoxicity of the seizure activity itself rather than a direct toxic effect. Muscular weakness and paralysis occurring 1-4 days after the resolution of an acute cholinergic toxidrome, the intermediate syndrome is usually not diagnosed until significant respiratory insufficiency has occurred; it is nevertheless a major cause of OP-induced morbidity and mortality and requires aggressive supportive treatment. The condition usually resolves spontaneously in 1-2 weeks.Treatment of OP intoxication relies on prompt diagnosis, and specific and immediate treatment of the lifethreatening symptoms. Since patients suffering from OP poisoning can secondarily expose care providers via contaminated skin, clothing, hair, or body fluids. EMS and hospital caregivers should be prepared to protect themselves with appropriate protective equipment, isolate such patients, and decontaminate them. After prompt decontamination, the initial priority of patient management is an immediate ABCDE (A : airway, B : breathing, C : circulation, D : dysfunction or disability of the central nervous system, and E : exposure) resuscitation approach, including aggressive respiratory support, since respiratory failure is the usual ultimate cause of death. The subsequent priority is initiating atropine therapy to oppose the muscarinic symptoms and diazepam to prevent or control seizures, with oximes added to enhance acetylcholinesterase (AChE) activity recovery. Large doses of atropine and oximes may be necessary for poisoning due to suicidal ingestions of OP pesticides.

Endoscopic Approach and Management of Parasellar Lesions

The parasellar region is the location of a wide variety of inflammatory and benign or malignant lesions. A pathological diagnostic strategy may be difficult to establish relying solely on imaging data. Percutaneous biopsy through the foramen ovale using the Hartel technique has been developed for decision-making process. It is an accurate diagnostic tool allowing pathological diagnosis to determine the best treatment strategy. However, in some cases, this procedure may fail or may be inappropriate particularly for anterior parasellar lesions. Over these past decades, endoscopy has been widely developed and promoted in many indications. It represents an interesting alternative approach to parasellar lesions with low morbidity when compared to the classic microscopic sub-temporal extradural approach with or without orbito-zygomatic removal. In this chapter, we describe our experience with the endoscopic approach to parasellar lesions. We propose a complete overview of surgical anatomy and describe methods and results of the technique. We also suggest a model of a decision-making tree for the diagnosis and treatment of parasellar lesions.

Anxiety and severity of illicit substance use in adolescence: Evaluating the mediating role of perceived coping styles

The purpose of this study was to examine whether coping styles (Active coping, Internal coping and Withdrawal coping) mediated the relationships between anxiety and severity of illicit substance use among a sample of 110 Swiss adolescents ages 12-19 (M=16.3, SD=1.66). The current study tested two competing models of anxiety on severity of illicit substance use. In the first model, we tested the direct effect of trait anxiety (STAI-Y anxiety score) on severity of illicit substance use (ADAD drug use severity rating), while in the second models we examined the mediating role of coping styles in the link between trait anxiety and severity of illicit substance use. Path models indicated that the associations between trait anxiety and severity of illicit substance use are partially mediated by active and withdrawal coping styles. Limitations of the findings and implications for prevention of substance use in adolescence are discussed.