Suraj Wasudeo Nagre1* and K N Bhosle22
1Associate Professor, Department of C.V.T.S, Grant Medical College, Mumbai, India
2Professor and Head of Department C.V.T.S, Grant Medical College, Mumbai, India
Received: 09 October, 2017; Accepted: 18 October, 2017; Published: 20 October, 2017
Suraj Wasudeo Nagre, Associate Professor, Department of C.V.T.S, Grant Medical College, Mumbai, India, E-mail:
Nagre SW, Bhosle KN (2017) Ministernotomy Thymectomy in Mysthania Gravis-Future. J Cardiovasc Med Cardiol 4(4): 070-074. 10.17352/2455-2976.000053
© 2017 Nagre SW, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
A thymectomy is the surgical removal of the thymus gland. The thymus has been demonstrated to play a role in the development of MG. It is removed in an effort to improve the weakness caused by MG, and to remove a thymoma if present.About 10% of MG patients have a tumor of the thymus called a thymoma. Most of these tumors are benign and tend to grow very slowly; on occasion they are malignant (“cancerous”).A thymectomy is recommended for patients under the age of 60 (occasionally older) with moderate to severe MG weakness. It is sometimes recommended for patients with relatively mild weakness, especially if there is weakness of the respiratory (breathing) or oropharyngeal (swallowing) muscles. It is also recommended for all patients with a thymoma. A thymectomy is usually not recommended for patients with weakness limited to the eye muscles (ocular myasthenia gravis). The neurological goals of a thymectomy are significant improvement in the patient’s weakness, reduction in the medications being employed, and ideally eventually a permanent remission (complete elimination of all weakness off all medications). There are three basic surgical approaches transternal, transcervical and videoscopic[VATS] thymectomy each with several variations. Regardless of the technique employed, the surgical goal is to remove the entire thymus. Many believe this should include removal of the adjacent fat; others are less sure.Here we give our study report of comparision between full sternotomy against ministernotomy thymectomy patients preopt, intraopt and postopt factors, fifteen patients each in two group with ten year experience
Myasthenia gravis (MG) is an autoimmune disease resulting from the production of antibodies against postsynaptic nicotinic acetylcholine receptors at the neuromuscular junction . These antibodies are responsible for the reduction of the number of postsynaptic nicotinic acetylcholine receptors and therefore, explain the clinical picture of MG, characterized by progressive weakness and fatigue of the voluntary musculature, which worsens during repetitive exercise and improves with rest. Because fatigue is progressive, it is more intensive at the end of the day. There are no sensory, reflex, or coordination disturbances in MG . Ocular weakness is the first manifestation in half of the patients, who usually complain of ptosis or diplopia. Muscular weakness is symmetrical and generalized weakness is observed in up to 85% of the patients . However, the clinical course may be extremely different, and the onset of symptoms may be gradual or abrupt. In addition, there may be spontaneous remissions or aggravations. The treatment of MG may be surgical or nonsurgical. The nonsurgical treatment includes the use of anticholinesterase agents, immunotherapy (corticosteroids, azathioprine, immunoglobulins), and plasmapheresis . The surgical removal of the thymus gland is controversial. The benefit of thymectomy was first reported by Sauerbruch in 1912 and has been demonstrated repeatedly since the observations of Blalock and colleagues in 1939. The optimal approach and the extent of the resection to be performed are still under discussion. Unfortunately, it is not possible to directly compare many of these nonsurgical and surgical series owing to differences in several areas. The sternotomy does have the advantage of providing excellent visualization and allowing an extended resection when necessary. The optimal surgical approach varies with the surgeon’s experience and preference and most of the approaches are currently acceptable. Historically, thymectomy has been carried out using two approaches: transcervical , or transsternal incisions [6, 7]. However, less invasive techniques may be used: partial sternotomy and video-assisted thoracoscopy [8, 9]. Our surgical approach was partial sternotomy, aiming at removing all thymic and perithymic tissue, was consistently applied in each patient of the series. Such an approach allows excellent visualization of the thymus, its vascular attachments, and perithymic tissues. All visible mediastinal fat was excised with the thymus. The boundaries of the extracapsular plane resection are the thyroid gland superiorly, the phrenic nerves laterally, and the pericardial sac and adjacent mediastinal pleura inferiorly. This study aims at evaluating thymectomy by partial median sternotomy.
• To evaluate and compare full sternotomy versus ministernotomy in thymectomy for myasthenia patients and to compare the risk benefits in both the groups.
• What is the difference between both groups in intraoperative and postoperative factors?
• What will be the choice of approach for thymectomy in present as well as future?
Patients and Methods
From May 2007 to May 2017, 30 patients (70% women) underwent thymectomy out of which 15 by partial median sternotomy and 15 by full sternotomy [Table 1] at the Grant Medical College and Sir J.J.Hospital, Byculla, Mumbai.
At the Sir J.J. Hospital according to the neurologic team, in the general untreated myasthenic population the percentage of crises is 2.8% yearly and in the thymectomized patients or those treated with corticosteroids it is 0.8% a year. These data make thymectomy indicated to all patients diagnosed with MG, except in the following cases: 1. During the initial stage, when spontaneous remission is still possible (usually within the first year of onset). 2. In patients younger than 12 years of age, in the beginning of our study the thymectomy was not usually indicated because the thymus was considered important in the initial development of adequate immune responses. Preoperative preparation depends on the clinical condition of the patient. If there are only motor symptoms, with no bulbar impairment, the patient is treated with minimum doses of anticholinesterase drugs, as required for regular activities. All patients with clinical symptoms, including those with respiratory failure requiring mechanical ventilation, are initially treated in the intensive care unit with anticholinesterase drugs, corticosteroids, immunosuppressors, and some patients are treated with plasmapheresis. Thymectomy was only performed after a significant clinical improvement. None of our patients were ventilator-dependent at the time of thymectomy [Table 2].
The patient is placed in a supine position with a pad under the shoulders. A vertical midline incision is made starting 2 cm below the suprasternal notch up to the level of the fourth intercostal space . Longitudinal partial sternotomy provides adequate approach to the thymus. Advantage was, the incision may be inferiorly prolonged, by total sternotomy, or superiorly, by adding a transversal incision at the base of the neck. The incision is carried down through the subcutaneous tissue to expose the upper sternal border, presternal fascia, and the musculature, which are incised down to and through the sternal periosteum. The superior mediastinum, above the manubrium, is dissected with an electrocautery and bluntly with the finger to clear the posterior wall of the sternum away from the surrounding vascular structures. The bone of the manubrium is divided with a compressed air or an electric-powered saw in a downward dissection. The entire manubrium and the upper part of the sternal body down to the fourth intercostal space are divided (Figure 1). Subsequently, the upper mediastinum is exposed by Finochietto’s retractor with a lateral and progressive retraction. The thymus is then exposed. It must be totally removed, including its surrounding fat, starting superiorly from the base of the thyroid gland, using the phrenic nerves as lateral limits and proceeding inferiorly until the pericardium (Figure 2). Generally, we use a Duval clamp to expose the thymus and to allow sufficient tension for dissection of the thymus from the underlying structure. During dissection, the mediastinal pleura should be pushed laterally, to avoid inadvertently rupturing the pleura. If this should happen, it must be sutured immediately or ICD should be inserted at end of surgery. The surgeon should identify the phrenic nerves and avoid excessive manipulation and lesion, to avoid postoperative diaphragmatic palsy, which could seriously impair the clinical outcome of the patient. After resection, the thymic bed is carefully assessed to assure a radical thymectomy, adequate hemostasis, and that the pleural spaces are intact. A Portovac suction catheter is routinely placed close to the sternal notch. The sternum is then sutured with stainless steel wire no. 4 or 5, muscular layers are sutured with a 2-0 Vicryl thread, the subcutaneous and skin layers are sutured to conclude the procedure. A full sternotomy to complete the operation was not needed in our series. Successful management of these patients requires close cooperation among the neurologist, thoracic surgeon, anesthetist, nurses, and physiotherapists.
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