Other Diseases: Hydrocephalus, Neuromuscular Disease, Plexopathy and Mononeuritis

Myasthenia gravis (MG) is an autoimmune neuromuscular disorder characterized by weakness and fatigability of skeletal muscles caused by dysfunction/destruction of acetylcholine receptors at the neuromuscular junction. Myasthenia gravis presents with fatigue, ptosis, diplopia, dysphagia, respiratory difficulties, and progressive weakness in the limbs, leading to difficulty in movement. Diagnosis is established based on clinical presentation, detection of antibodies, and electrophysiologic studies. Management is aimed at increasing the activity of acetylcholine at the neuromuscular junction and suppression of antibodies. This disease can be associated with thymomas and thymic hyperplasia, and thymectomy is sometimes indicated. Myasthenia gravis can progress to a life-threatening cholinergic crisis with respiratory failure, but this is preventable with appropriate management. Prognosis is generally good with treatment, and some patients can achieve a long-term remission.

Plexopathy is a peripheral neuropathy at the level of the brachial or lumbosacral plexuses leading to sensory, motor or sometimes autonomic deficits. The etiology for this pathology vary from compression, inflammation, or ischemia to radiation.

This article runs through the common presentations, pathophysiology, differential diagnoses and common therapies for mononeuropathies. It looks in detail at a number of common nerve injuries, including radial nerve, ulnar nerve, brachial plexus, phrenic nerve, common peroneal nerve and the femoral nerve. It covers common examination findings in order to make an accurate and specific diagnosis.

Hydrocephalus or water in the brain is referred to accumulation of the cerebrospinal fluid (CSF) in the subarachnoid space and cerebral ventricles leading to increased intracranial pressure.