A propensity score analysis for comparison of T-3b and VATET in myasthenia gravis.

OBJECTIVE: We performed propensity score (PS) models to compare the outcome of patients with myasthenia gravis (MG) submitted to 2 different surgical approaches: extended transsternal (T-3b) or thoracoscopic extended thymectomy (VATET). METHODS: Patients' clinical data were retrieved from the MG database of the C. Besta Neurologic Institute Foundation. In the PS analysis, a matching ratio of 1:1 of the main clinical variables was obtained for the 2 groups of patients and treatment effect was estimated by comparing their outcome. RESULTS: A total of 210 patients met the inclusion criteria, by having a complete set of clinical data, and were included in the PS model; a matched dataset of 122 participants (61 per group) showed an adequate balance of all the covariates. Our analysis demonstrated that 68.9% of patients who had thymectomy by the VATET technique reached the pharmacologic remission/remission status at 2 years from thymectomy compared to 34.4% of those operated on by the T-3b technique (p < 0.001), had a lower INCB-MG score (p < 0.001), and had less muscle fatigability (p = 0.004). Similar results were found considering only nonthymomatous patients with MG. Results were also confirmed by paired statistical tests. CONCLUSIONS: Our PS matching analysis showed that VATET is a reliable and effective surgical approach alternative to T-3b in patients with MG who are candidates for thymectomy. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that for patients with MG, VATET is more effective than T-3b thymectomy.

Perioperative management in myasthenia gravis: republication of a systematic review and a proposal by the guideline committee of the Japanese Association for Chest Surgery 2014.

Thymectomy is regarded as a useful therapeutic option for myasthenia gravis (MG), though perioperative management in MG patients is largely empirical. While evidence-based medicine is limited in the perioperative management of MG patients, treatment guidelines are required as a benchmark. We selected issues faced by physicians in clinical practice in the perioperative management of extended thymectomy for MG, and examined them with a review of the literature. The present guidelines have reached the stage of consensus within the Japanese Association for Chest Surgery.

EFNS/ENS Guidelines for the treatment of ocular myasthenia.

BACKGROUND AND PURPOSE: The symptoms of acquired autoimmune ocular myasthenia are restricted to the extrinsic eye muscles, causing double vision and drooping eyelids. These guidelines are designed to provide advice about best clinical practice based on the current state of clinical and scientific knowledge and the consensus of an expert panel. SEARCH STRATEGY: Evidence for these guidelines was collected by searches in the MEDLINE and Cochrane databases. The task force working group reviewed evidence from original articles and systematic reviews. The evidence was classified (I, II, III, IV) and consensus recommendation graded (A, B or C) according to the EFNS guidance. Where there was a lack of evidence but clear consensus, good practice points are provided. CONCLUSIONS: The treatment of ocular myasthenia should initially be started with pyridostigmine (good practice point). If this is not successful in relieving symptoms, oral corticosteroids should be used on an alternate-day regimen (recommendation level C). If steroid treatment does not result in good control of the symptoms or if it is necessary to use high steroid doses, steroid-sparing treatment with azathioprine should be started (recommendation level C). If ocular myasthenia gravis is associated with thymoma, thymectomy is indicated. Otherwise, the role of thymectomy in ocular myasthenia is controversial. Steroids and thymectomy may modify the course of ocular myasthenia and prevent myasthenia gravis generalization (good practice point).

The ageing and myasthenic thymus: a morphometric study validating a standard procedure in the histological workup of thymic specimens.

The thymus is believed to play an important role in the pathogenesis of myasthenia gravis (MG). The 80% of MG patients with anti-acetylcholine receptor autoantibodies fall into three clinical subgroups: 1) thymoma; 2) early-onset MG (

Learning curve in videothoracoscopic thymectomy: how many operations and in which situations?

OBJECTIVE: Videothoracoscopic learning curve is known to vary among different surgeons, and may be influenced by patients and various situations. We aimed to analyze the learning curve of a surgeon in videothoracoscopic thymic surgery for myasthenia gravis. METHODS: This is a descriptive single-center study using collected clinical data from 90 patients undergoing videothoracoscopic thymic surgery between June 2002 and September 2006. Cumulative summation (CUSUM) model was used to evaluate the learning curve for videothoracoscopic thymectomy operations. Unsuccessful situations were accepted as longer operation time, surgeon-related open conversions, readmissions and postoperative complications. Factors affecting longer operation time (patients with operation time longer than the average) and longer postoperative stay (patients with postoperative hospital stay longer than average) were analyzed. RESULTS: Body mass index (BMI) was the only predictor of longer operation time (23.04+/-2.93 vs 25.61+/-2.70 (p=0.001) independent samples test). The amount of prescribed pyridostigmine was the only factor for longer hospital stay (213.3+/-101.5 mg vs 270. 0+/-122.6 mg (p=0.044) Mann-Whitney U-test). CUSUM analysis demonstrated a learning curve with success rates of 80%, 90% and 98%, respectively in the first 30 patients, the next 31-60 patients and after 60 patients. Median operative time declined with surgeons' experience (p<0.001). CONCLUSIONS: A chest surgeon can have a high success rate in videothoracoscopic thymectomy (98%) after 60 operations.

Myasthenia gravis in South Africans: racial differences in clinical manifestations.

We present data on the phenotypic variation in myasthenia gravis of 205 subjects from a multi-racial South African cohort. Consecutive subjects seen more than twice from 1996 to 2006, were included. Documented observational data included a myasthenia gravis and extra-ocular eye muscle score. Results showed Black subjects were more likely than Whites to develop treatment-resistant complete ophthalmoplegia and ptosis (18% vs. 2%; p=0.041). Of the 14 patients with this phenotype, 13 had generalised disease and positive AChR antibodies. Despite similar sized cohorts, White subjects were more likely than Blacks to develop generalised myasthenia poorly responsive to therapy (p=0.005). There were no significant racial differences in the time between diagnosis to initiation of therapy, or the performance and timing of thymectomy. The racial variation in some phenotypic features of myasthenia gravis and outcome to therapy, highlights the need to study biological factors in different subgroups to develop a more rational approach to immuno-suppressive therapy.

[Thymectomy for autoimmune myasthenia gravis].

Thymectomy has been performed as surgical treatment for autoimmune myasthenia gravis (MG) since the mid-1900s. Although it has been performed for more than half a century, there has been no report objectively confirming the validity of this treatment. Many groups have reported that surgery is effective in treating patients with MG, but the indications and type of surgery differ in each case. In addition, there has been no comparative trial of the results of surgery and natural progression of the disease. To resolve this situation, it would be desirable to standardize the indications for surgery in MG patients and to establish the surgical approach, as is being attempted by the Myasthenia Gravis Foundation of America although the results have not yet been announced. With recent advances in video-assisted surgery, the number of institutions in which thoracoscopic surgery is performed has increased. However, it appears that improvement in MG symptoms is dependent on the extent of resection in thymectomy. With the cervical or thorascopic approach, the extent of resection appears to be less than that using the transsternal or cervical plus transsternal approach. Before establishing a standard surgical approach, the validity of thymectomy for the treatment of MG should be confirmed in a randomized, controlled trial.

Anestesia para timectomia en el paciente con diagnóstico de miastenia gravis

Se realizó un estudio de tipo retrospectivo para analizar las variables que se relacionan con el manejo anestesiológico de la Miastenia Gravis. La investigación incluyó 43 pacientes que fueron intervenidos quirúrgicamente en el Hospital San Juan de Dios de Bogotá, durante un período de cuatro años. Se estudiaron las variables que surgieron desde la visita preanestésica hasta la recuperación postoperatoria, realizando correlaciones de significancia estadística entre ellas. Se utilizó el paquete estadístico EPI Info Vesrión 5.0 para el análisis. Los resultados mostraron, como en otros estudios, un predominio del sexo femenino en los pacientes intervenidos, con edad promedio de 31 años para las demas y 20 años para los caballeros, sin que esta diferencia sea estadísticamente significativa. Hubo correlación significativa (p<0.05) entre: a) tiempo quirúrgico y tiempo de anestesia (r= 0.87); b) presencia de espirometría y medicación con prostigmine; c) tensión arterial promedio (sistólica, diastólica y media), con uso de diversos halogenados; e) tipo de halogenado y tiempo quirúrgico; f) complicaciones consignadas y calificación anotada del mantenimiento anestésico; y finalmente, entre la fecha (año) de la cirugía y la extubación en sala de cirugía

Combined cervicothoracic approach in thymectomy for myasthenia gravis.

Thymectomy was performed for myasthenia gravis on 30 patients, using a new approach with a collar incision which gave full exposure of the retrothyroid space and was directly connected to a median sternotomy. The thymus was removed en bloc without pleural incision. There was no perioperative mortality and the only complications were transient respiratory insufficiency in two cases. The postoperative hospital stay was 3-9 (mean 5.8) days. The effect of thymectomy was evaluated after 2-8 years at the Department of Neurology, when changes in symptoms (stages I-IV) or medication (need for cholinesterase inhibitors) were registered. The total clinical improvement rate was 97%, with 3% of the patients improved three stages, 33% two stages and 60% one stage compared with the preoperative classification. Twenty patients (67%) were asymptomatic at follow-up and six (20%) also required no medication. The medication need was reduced in 70% of cases (mean reduction 42%). Our cervicothoracic approach resulted in the same rate of improvement as in studies using more extensive transsternal procedures, but the morbidity was lower, with no complications requiring prolonged hospital stay. The morbidity was also less than after only transcervical procedures aiming to perform total thymectomy--a prerequisite for maximal and lasting benefit from surgery. Moreover, as this cervicothoracic approach is simple and safe, it can be recommended as an option in the surgical management of myasthenia gravis.

Thymectomy in myasthenia gravis. Results of 662 cases operated upon in 15 years.

The results of thymectomy in the treatment of myasthenia gravis (MG) are reviewed in the light of a personal series of 662 MG patients, operated upon during the last 15 years. In 500 MG patients without thymoma, the following results have been achieved: remission 37.9%, improvement 49.4%, unchanged or worse 7.4%, dead 5.2%. There is no sex prevalence and the remission rate is higher in patients under 40 years of age (P less than 0.01), with mild disease (P less than 0.05), with a MG duration of less than 1 year (P less than 0.05) and with a follow-up length of between 5 and 10 years (P less than 0.01). No correlations are found between outcome and thymic histology. The results of 162 MG patients with thymoma are: remission rate 15.7%, improvement 60.3%, unchanged or worse 3.7% and dead 20.1%. The remission rate is higher with mild symptoms (P less than 0.05) and when the tumour is encapsulated (P less than 0.02). The postoperative mortality is 0.8% (none in the last 5 years) for non-thymomatous MG and 4.9% for thymomatous MG (2 of 8 patients died of pancytopaenia and 1 of pulmonary embolism).

La timectomia en el tratamiento de la miastenia gravis / The thymectomy in the treatment of myasthenia gravis

La asociacion entre glandula timica y la miastenia gravis ha sido establecida desde hace muchos anos y en multiples series se ha comprobado la mejoria y remision de esta entidad al resecar el timo. Se presentan 21 casos de pacientes com miastenia gravis tratados con timectomia desde 1981 en el Hospital Universitario San Juan de Dios de Bogota. Se revisaron los aspectos epidemiologicos, diagnosticos, clinicos y de tratamiento medico y quirurgico. Los resultados muestran una morbilidad del 28.5% con mortalidad del 0% y remision y mejoria del 80% a 4 meses, cifras comparables con otras series de pacientes tratados mediante timectomia transversal. Se insiste en el tratamiento multidisciplinario que incluye las secciones clinicas de neurologia, cirugia, cuidados intensivos, anestesia y patologia.