Acquired blepharoptosis

Evaluation and Management of Blepharoptosis

Drooping of the upper eyelid margin, aka blepharoptosis or "ptosis", is common. Whether the ptosis is severe or mild, congenital or acquired, aponeurotic or neuropathic or myopathic, proper management always begins with a detailed history and evaluation of the patient. The information gathered will direct the surgeon in choosing the technique most likely to give the best result. This article will briefly review common causes of ptosis, the evaluation of the ptosis patient as well as the two most common types of surgical intervention.

Patients with ocular symptoms referred for electrodiagnosis: how many of them suffer from myasthenia gravis?

The aim of this study was the diagnosis of patients with isolated ocular manifestations (ptosis and/or diplopia) referred for electrophysiological evaluation to the electrodiagnostic laboratory of a University Neurological Department. Examination was performed either in inpatient status or in outpatient basis. We analyzed the clinical, electrophysiological and other laboratory data in 79 subjects. Myasthenia gravis (MG) was diagnosed in 38 %, 45.6 % in other diseases (Graves disease, blepharospasm, IIId cranial verve palsy, multiple sclerosis, stroke, etc.), while in 16.5 %, the cause remained unidentified. Symptoms fluctuation was significantly more frequent in the myasthenic patients, compared to patients with other diseases. The presence of both diplopia and ptosis are more likely due to MG rather than other pathology.

The decreased expression of thioredoxin-1 in brain of mice with experimental autoimmune myasthenia gravis

Myasthenia gravis (MG) is an autoimmune disease caused by circulating antibodies that block acetylcholine receptor (AchR) at the neuromuscular junction. There is the cognitive and memory impairment in patients with MG. However, the molecular mechanisms underlying the alteration of central nervous system in MG remain unknown. In the present study, we found that the level of malondialdehyde (MDA) was increased in the brain of experimental autoimmune myasthenia gravis (EAMG). Furthermore, the expression of thioredoxin-1 (Trx-1) and the activity of cAMP response element-binding protein (CREB) were significantly decreased in frontal lobe and hippocampus of mice with EAMG. We also found that the expression of pro-apoptotic C/EBP homologous protein (CHOP) was increased in the frontal lobe and hippocampus of mice. However, the expressions of glucose regulated protein 78 (GRP78/Bip) was not changed in same areas. Inversely, the expressions of pro-caspase-12, pro-caspase-3 and pro-caspase-9 were decreased. These data indicate that Trx-1 mediated endoplasmic reticulum and mitochondria pathways are involved in brain damage in MG. Trx-1 may be a pivotal target for brain protective treatment in MG.

Myasthenia gravis: diagnosis and treatment

PURPOSE

To provide information about myasthenia gravis (MG), including pathophysiology, differential diagnosis, treatments, diagnostic work up, patient teaching, and diagnostic algorithms for ptosis and weakness related to MG.

DATA

Clinical and research journal articles, medical textbooks, and a patient with MG.

CONCLUSIONS

Myasthenia Gravis is a very complex disease with many different signs and symptoms, which may be quite noticeable or vague. The presenting symptoms of ptosis and/or diplopia should cause the clinician to consider a work-up for MG.

IMPLICATIONS FOR PRACTICE

Because of the low incidence MG (1 in 10,000) has in the U.S., a delay in diagnosis of one to two years is not uncommon. It is vital to diagnose this disease and begin treatment as soon as possible to decrease the signs and symptoms.

Does myasthenia gravis affect the brain?

Associations between myasthenia gravis (MG) and CNS functions have been made for over 80 years. An increased incidence of psychiatric disorders, epilepsy and multiple sclerosis as well as electroencephalographic (EEG) abnormalities and abnormal evoked responses have been noted in patients with MG. Descriptions of sleep and memory disturbances in MG patients appeared as knowledge accumulated about the role of brain cholinergic systems in sleep and memory. The inference of many of these studies has been that the alleged central cholinergic effects in MG were caused either by the anticholinesterases used to treat MG or by antibodies to muscle nicotinic acetylcholine receptor (nAchR) present in the serum and cerebrospinal fluid (CSF) of MG patients. The antigenic differences between muscle nAchR and neuronal nAchRs, together with the very low concentrations of muscle nAchR antibodies in the CSF, make highly unlikely the claims that CNS cholinergic systems are affected by these muscle antibodies in MG patients. Evoked response abnormalities, if indeed present, are more likely caused by peripheral than central mechanisms, and sleep abnormalities in MG also probably originate in the periphery rather than in the CNS, the result of hypoxia caused by oropharyngeal, intercostal and diaphragmatic muscle weakness which may worsen during sleep, especially during REM sleep. Such hypoxia may account for some of the EEG abnormalities noted in MG patients, but the association of MG with epilepsy appears to be either coincidental or the result of uncontrolled MG. Significant excessive daytime sleepiness resulting from sleep disturbances can also impair memory and the performance of MG patients on neuropsychological tests, as can the presence of mental depression. The psychological aspects of MG can be attributed to the expected consequences of a chronic but unpredictable neuromuscular disease involving weakness of breathing, swallowing, talking, limb and eye movement. Considering the number and variety of claims for direct CNS involvement in MG, the evidence for this is remarkably unconvincing. The quality of MG treatment, both physical and psychological, is a presently undefined variable which might help explain the diametrically opposed results which have been obtained in some of the studies reviewed. Adequate respiratory muscle strength during sleep is an often overlooked peripheral influence upon mental functioning and general well-being of MG patients.