indications for covered self - expandable metallic airway stent removal include recurrent mucous plugging of the stent , excessive or recurrent granuloma formation , migration of the stent , stent infection , recurrence of stenosis , stent failure , stent fractures and accomplishment of treatment . usually , it is tedious to remove a stent because of their embedding in the bronchial mucosa and epithelization of the inner surface .
granuloma formation at the extremities is a relative common occurrence in covered metallic stents possibly resulting from the radial force applied against the airway wall and the friction exerted .
we report a case of covered self expandable metallic stent removal with a rigid bronchoscope under general anesthesia .
the case is unique because it had almost all the common complications associated with the stent placement but it was successfully removed without much ado . to the best of our knowledge
this is the first case of successful removal of a complete stent reported from india .
a 21 year old female presented with complaints of increasing dyspnoea and cough with pain chest for last two weeks .
patient had a past history of benign tracheal stenosis which was opened up by endobronchial electro surgery followed by placement of a self expandable metallic airway covered stent .
x - ray chest done one and a half year back showed stent well in place [ figure 1 ] .
x - ray chest done one and a half year back showing stent well in place bronchoscopy was done under local anesthesia and a stenosis was observed well above the level of the stent [ figure 2 ] with granulation tissue inside the stent [ figure 3 ] , lower end of the stent was fractured , carina was not visualized and stent was seen entering upper part of right main bronchus [ figure 4 ] .
the beveled edge of the rigid scope was advanced between the stent wall and the airway mucosa thus creating a space between them .
the circular extraction loop at the upper end of the metallic stent was grasped with a rigid optical alligator forceps and pulled in the lumen of rigid bronchoscope with continuous winding movements gradually separating the stent from the tracheal wall . immediately after that
this is one of the rare cases of successful removal of self expandable metallic airway covered stent in benign tracheal stenosis .
stenosis above the level of the stent granulation tissue inside the stent and at the margins fracture of stent at its lower end ( stent is seen at upper part of right main bronchus , carina is not visualized ) the stent after removal
the management of patients with tracheal / bronchial strictures of benign etiology can be quite challenging .
though surgical tracheal sleeve resection and reconstruction remains the gold standard for most benign airway strictures , non - surgical modalities such as laser photocoagulation and resection , balloon dilatation , electrocautery and stenting of the airway have been developed to deal with airway stenosis .
various inoperable benign airway disorders are considered for airway stenting , like post intubation tracheal stenosis , tracheal burn or trauma , tracheo - broncho - malacia and extrinsic compression of trachea . though silicone prostheses are considered to be first choice in benign diseases
their use is less suited , especially in airway wall malacia or distal and angular stenosis where sems are preferred .
the disadvantages of the silicone stents are high migration rate , small lumen to wall thickness ratio and difficulty in clearing the secretions . on the other hand
, the major drawback for placement of sems in benign situations is their difficult repositioning and removal in situations like excessive granulation tissue , stent fractures and stent migration .
the complications of stent removal include significant oozing , tracheal mucosal dehiscence , tracheal puncture requiring thoracotomy , retained stent pieces , need for restenting , respiratory failure , tracheotomy , and even death . in our case ,
various authors have come up with different methods of removal of the stent , like the technique of nashef et al . , which was similar to that of rolling spaghetti on a fork , but much more difficult and at least equally messy .
they further observed that there may be several fractures of the stent , which have to be removed piece by piece . in our case
filler et al . , used a metal suction catheter to dissect the stent from the airway wall before extraction with the forceps .
zakaluzny et al . , employed a rigid suspension laryngotracheoscope and used optical forceps to dissect the stent from the airway wall .
alligator forceps were then employed to grasp and extract the stent through the rigid scope while the scope was advanced further into the airway .
we first separated the stent from the tracheal wall and then removed all the works ( scope , forceps and the stent ) in one piece .
to conclude , this case is unique for many reasons , firstly , it had almost all of the complications that can be associated with stent placement ( stenosis of trachea at the upper end of the stent , extensive granuloma formation , migration of the stent downwards and fracture of the stent at its lower end ) , secondly , we were able to remove the stent in toto [ figure 5 ] and lastly , there were no complications after removal of the stent .
further studies are needed to re evaluate their removal successfully and safely and to produce better designed and technically superior stents like bio - absorbable stents which may not have to be removed at all .
 covered self expandable metallic airway stents ( sems ) have been used for benign tracheal stenosis , post intubation tracheal stenosis , tracheal burn or trauma , tracheo - broncho - malacia , and extrinsic compression of trachea . 
 their placement is considered to be permanent , with open surgery the only way to remove the stent , though there are few cases reports of their removal with the bronchoscope , but the complications after their removal are very high . in our patient , one and a half years after placement of sems , she developed cough with dyspnoea , video bronchoscopy showed stenosis above the level of stent with granulation tissue inside the stent , stent fracture in lower part and stent migration to right main bronchus , thus she had all conceivable complications of stent placement . 
 the stent was removed with the help of rigid bronchoscope under general anaesthesia . 
 she was discharged the following day . 
 the case is being reported because it was unique in having all the possible complications of stent placement , and rare as we could take out the stent in toto . 
 thirdly , the stent could be removed without any complication . 
INTRODUCTION
CASE REPORT
DISCUSSION