Thymectomy For Myasthenia Gravis Research Articles

Caution urged in childhood thymectomy for myasthenia gravis

Caution urged in childhood thymectomy for myasthenia gravis

The Value of Thymectomy in Myasthenia Gravis

In the absence of a prospective randomized study of patients treated conservatively or with thymectomy, a computer-assisted retrospective matches study was devised. Of 563 patients treated for myasthenia gravis without thymoma up to 1965, 104 had thymectomy. With computer assistance, each surgical patient was matched with a medical patient on the basis of age, sex, and severity and duration of disease. On this basis 80 of the 104 surgical patients could be matched satisfactorily. There were 16 males and 64 females in each of the matched surgically treated and medical control groups. A complete remission was experienced by 27 of the 78 patients in the surgical group as compared to 6 of the medical group. Improvement was noted by 26 of 78 surgically treated patients and 13 of 78 receiving medical treatment. Survival for patients having thymectomy. Thirty-four patients in the medical group had died as compared to 11 in the surgical group. Comparison of survival in relation to sex, duration of symptoms, or age (less than 30 or less than 30 years) did not show a significant difference. Until more effective treatment is available for myasthenia gravis, thymectomy deserves consideration for both sexes, and with increased age or long duration of symptoms.

Electrophysiologic evaluations of thymectomy in myasthenia gravis

Electric testing was performed in 106 myasthenia gravis patients before and after transcervical thymectomy. Twenty-nine were followed for 3 to 24 months. Results were correlated with thymic pathology, duration of disease, age at operation, and follow-up clinical status. Electric improvement was significantly greater in patients without thymic germinal centers or with only rare to occasional germinal centers, in patients operated on within 1 year after onset of symptoms, and in patients under age 30. Electric improvement immediately after thymectomy heralded later clinical improvement in those patients without germinal centers or with rare to occasional germinal centers. Electric-clinical correlations were excellent in patients with longer follow-up. Serial electric testing provides an objective evaluation of the patients' clinical status post-thymectomy.

Anesthesia for Transcervical Thymectomy in Myasthenia Gravis

This review of anesthetic experience in 100 cases of transcervical thymectomy for myasthenia gravis (MG) at The Mount Sinai Hospital (1970-1974) underlines current trends in the surgical management at Mount Sinai, where transcervical thymectomy is the procedure of choice for all patients with nonthymomatous MG and for selected patients with thymomatous MG. The transthoracic approach is now limited to malignant thymomas and tumors not accessible through the transcervical approach. Formerly, patients coming for thymectomy either already had a preexisting tracheostomy, or an elective tracheostomy was performed at the time of thymectomy. Since 1972, none of these patients has had elective tracheostomy at the time of operation, and only four were performed in the postoperative period, patients being intubated orotracheally at the time of operation. The tube is usually removed within 1 hour after completion of thymectomy. All patients are followed in the intensive care unit for 24 hours or longer, under close supervision of experienced personnel aware of the inherent problems and able to assist ventilation at any stage. This approach has greatly changed the postoperative course of this disease.

Evaluation of results of thymectomy in myasthenia gravis.

The results of thymectomy carried out in 150 cases of myasthenia gravis are discussed. In a group of 123 cases followed for 1 to 5 years after the operation, full remission was observed in 24.4% of cases, significant improvement in 36.6%, slight improvement in 24.4% and no improvement in 8.1%, while deterioration occurred in 1.6% of patients. No correlation was found between the result of the operation and the age and sex of patients, but better results were achieved in those treated surgically rather soon after the onset of symptoms. This correlation was particularly evident in the group with full remissions. The results obtained in the cases without thymic tumors were better than in the cases with tumors. No correlation was noted between the results of the operation and the histological characteristics of the thymus in the group with thymic hyperplasia and in the group with thymic atrophy. The surgically treated group (150 cases), compared with the conservatively treated group (75 cases), showed the superiority of the surgical method (lower rate of death and deterioration, higher rate of improvement and remission). In discussing the indications for surgical treatment the authors emphasize that advances in anaesthesiology in recent years have reduced the risk of operation. It is suggested that the indications for surgical treatment should be expanded and operations should be performed as early as possible after the onset of clinical manifestations without regard to the age and sex of the patient. Operation should not be considered in cases belonging to group 1, 2a (sometimes 2b) only, with duration of the disease over 8-10 years and with little or no progression of the process, if the presence of a thymic tumor has been excluded.

Studies in myasthenia gravis: Early thymectomy: Electrophysiologic and pathologic correlations

Indications for thymectomy in myasthenia gravis have been recently expanded to include all cases with extraocular symptoms as a result of the minimal morbidity and negligible mortality of the transcervical approach. As increasing numbers of patients with myasthenia gravis, covering the entire spectrum of generalized disease, have been added to the thymectomy population, a more accurate evaluation of the effects of the operation is possible. Our experience with 353 patients who have undergone thymectomy indicates that early thymectomy, particularly in patients who do not have thymic germinal centers, is followed by early remission of the disease. Delayed remission after thymectomy is related to the duration and severity of the disease, and to presence of thymic germinal centers. Germinal centers were found more frequently in patients with long duration of the disease and in patients in whom the disease had progressed to respiratory involvement. Marked improvement in electromyographic findings immediately after thymectomy was observed in the majority of patients who had had the disease for 1 year or less and where germinal centers were absent. The percentage of malignant thymomas was higher in patients who underwent thymectomy 1 year or more after the onset of symptoms of myasthenia gravis. These data indicate the importance of early thymectomy while the disease is still in the mild stages. Transcervical thymectomy is the treatment of choice as it is followed by a higher percentage of remissions and by less morbidity than other forms of treatment.

Recurrence of nonneoplastic thymus after thymectomy for myasthenia gravis. Report of two cases.

Recurrence of nonneoplastic thymus after thymectomy for myasthenia gravis. Report of two cases.

Thymectomy for myasthenia gravis: Long-term results in 74 cases

Thymectomy for myasthenia gravis: Long-term results in 74 cases

Thymectomy and Cancer—A Follow-Up Study

Three hundred and eighty-two patients undergoing thymectomy for myasthenia gravis at 4 London hospitals during the years 1942-64 have been followed to the end of 1967. Five of these patients died from extrathymic tumours while 5·5 would have been expected to do so from the national experience. An additional 5 patients developed non-fatal extrathymic tumours during the period of follow-up. These data provide no evidence that adult thymectomy is followed by an increased risk of neoplastic disease, but more prolonged follow-up will be required before a final conclusion can be drawn.

Thymectomy for myasthenia gravis in bantu children : J. Geefhuysen, M. Ronthal and M. A. Rogers. S. Afr. Med. J. 44:239–241 (February 28), 1970

Thymectomy for myasthenia gravis in bantu children : J. Geefhuysen, M. Ronthal and M. A. Rogers. S. Afr. Med. J. 44:239–241 (February 28), 1970

Thymectomy for myasthenia gravis in children

Thymectomy was performed on 14 children under 20 years of age with myasthenia gravis during the past 12-years. Objective pre- and postoperative evaluation was accomplished by determining blub ergograph responses, oropharyngeal and general muscle strength and vital capacity. The decision for prophylactic or concomitant tracheostomy was also based on this information. Significant objective improvement following thymectomy occurred in all but one of the patients (Groups A and B). The average age of the patient at the time of thymectomy was 13.3 years and the average duration of symptoms prior to thymectomy was 2.5 years. One child underwent thymectomy at the age of 2.5 years and has experienced substantial improvement (Group B) subsequently. Two patients, each 19 years of age, had a benign thymoma. One of these patients died two years after thymectomy, the only death in the series. The severity of symptoms prior to thymectomy did not influence the clinical response obtained from operation. Postoperative respiratory complications are common and fastidious care is imperative. Thymectomy appears to provide a good opportunity for improvement in symptoms of selected children with myasthenia gravis and may be attended with a low risk of mortality.

A further evaluation of thymectomy for myasthenia gravis

A further evaluation of thymectomy for myasthenia gravis

Immunological changes following thymectomy in myasthenia gravis.

Patients with myasthenia gravis show evidence of unusual immunological activity. Nastuk et al 14 demonstrated that in such patients serum complement (C') activity frequently lies outside the extremes of the normal range. From these findings and from consideration of other factors, they proposed the hypothesis that myasthenia GRAVIS is a disease in which autoimmune mechanisms play an important role. Strong support for this hypothesis was provided at the same time by Strauss et al 21 who demonstrated the presence of muscle binding, complement-fixing serum globulin in the serum of certain patients with myasthenia gravis. Simultaneously and independently, Simpson 17 proposed that myasthenia gravis is an autoimmune disease. Simpson reached his position from a reevaluation of clinical and pathological evidence. Since these beginnings, many immunological aspects of myasthenia gravis have been reported in more recent publications. 1,4,6-8,10,11,15,19 Well before any immunologic function of the thymus gland was demonstrated, thymectomy was performed

THYMECTOMY IN MYASTHENIA GRAVIS.

EXPERIENCE WITH THYMECTOMY for myasthenia gravis at Massachusetts General Hospital was fully described in 1960. 1 Since then, several changes have been made in our postoperative regimen. As a result, patients have shown a smoother and more comfortable postoperative course and mortality has been reduced. Therefore, the changes in postoperative care are worthy of record and will serve as an extension to the book. Thymectomy for myasthenia gravis has incurred a postoperative mortality of 7% to 10% during the past 15 years. In our experience, most of the complications and deaths have resulted from pulmonary complications which usually occur acutely during the first two to three days after operation. This has been manifest by copious upper respiratory secretions and weakness and inability to clear the airway, followed by inadequate gas exchange, atelectasis, and hypoxia. If untreated or compounded by intractable bronchospasm, this sequence of events has proved fatal. We feel

SYSTEMIC LUPUS ERYTHEMATOSUS, CIRRHOSIS AND ULCERATIVE COLITIS AFTER THYMECTOMY FOR MYASTHENIA GRAVIS.

THE thymus is accorded important functions in the development of normal and disordered immunologic systems of the body. Not only may immunologically competent lymphocytes with a wide range of specific antigenic activity be derived from the thymus, but the healthy organ may have an inhibitory influence that discriminates effectively against such mutating stem cells and their descendant clones.1 , 2 Although proposing the latter hypothesis, Burnet1 has been unable to find any immunologic disability after thymectomy in the human being. Because of the fundamental significance of such an association a case of systemic lupus erythematosus occurring after thymectomy for myasthenia gravis is . . .

Thymectomy for Myasthenia Gravis: A Record of Experiences at the Massachusetts General Hospital

A monograph on so uncommon a disease as myasthenia is well justified by the authors' experience with over 500 patients with this disorder seen at the Massachusetts General Hospital, 139 of whom have been subjected to thymectomy. On the basis of this unique experience, the authors have outlined the indications for in myasthenia gravis, the prognosis following operation, and surgical procedures which have reduced the mortality in the authors' series almost to zero. The monograph is much more comprehensive than is indicated by its title. It includes a general review of the historical background, current theories regarding neuromuscular transmission of the nerve impulse, as well as presumed functions of the thymus. In addition to the four chapters by the authors, the book includes such chapters as Pathology of the thymus gland by Benjamin Castleman; Radiologic features of myasthenia gravis by Laurence L. Robbins; Technic of thymectomy by Richard

Thymectomy for myasthenia gravis

1. 1. Myasthenia gravis appears to be related to an abnormality of the thymus. 2. 2. A significant number of patients with myasthenia gravis benefit from thymectomy. 3. 3. After thymectomy for myasthenia gravis, about one-third of patients are much improved, one-third somewhat improved and one-third unimproved. 4. 4. Young myasthenic women with a relatively short history of the disease, gradually losing ground, and without a tumor of the thymus benefit most from thymectomy. 5. 5. Patients with thymomas should have resection of the tumor regardless of the presence or absence of myasthenia. 6. 6. Thymectomy, with the patient under cyclopropane anesthesia, performed through a sternal-splitting approach in itself causes little risk. Deaths result after operation from pulmonary complications characteristic of myasthenia. 7. 7. The edrophonium test differentiates myasthenic crisis from cholinergic crisis, a dangerous and lethal complication of cholinergic treatment.

Technique of thymectomy for myasthenia gravis.

Preoperative Care 1. Regulation of basic requirement of neostigmine methyl sulfate (Prostigmin) must be exact, determined by hospital observation or long-term ambulatory control by the neurologist. 2. In the female, the date for surgery is chosen so as not to coincide with the expected menses. 3. Enemas are contraindicated in myasthenia gravis. 4. Preliminary medication consists of a sedative, such as pentobarbital (nembutal), plus atropine sulfate. Use of narcotics is not wise. 5. A continuous intravenous infusion of neostigmine methyl sulfate must be begun about one hour before anesthesia. The dose is calculated empirically as one-thirtieth of the daily oral dose, in milligrams. 6. Whole blood should be available. It is administered through a second, separate infusion to avoid interference with continuity of the neostigmine drip. Operative Management 1. The principles which permit the successful completion of thymectomy in myasthenia gravis include ( a ) coordinated teamwork of neurologist, anesthetist, and surgeon;