Dysfunction Following Thyroid Surgery
Dysfunction Following Thyroid Surgery
Voice plays a crucial role in human communication and function. Voice production is
 multidimensional, involving physiologic, biomechanical, and aerodynamic mechanisms that
 produce an acoustic output that is perceived by the auditory system. So its important to
 evaluate patients with voice disorders, whenever possible, to characterize the impact of the
 disorder(s) on all of the pertinent mechanisms/dimensions.
Voice changes due to laryngeal dysfunction after thyroid surgery are very common
 complication. However, very few data in the literatures are available which highlights the
 impact of thyroidectomy and effects of factors, such as patient age, sex, operation type,
 surgeons experience, laryngeal nerve injury and orotracheal intubation on voice of patients
 undergoing thyroid surgery. Prabhat AK et al. 2018 reported that, In majority of cases voice
 changes are transient. The voice recovery time ranges from less than one-month up to 6 months
 in majority of cases. Transient voice changes, such as voice fatique, and voice weakness or
 dysphonia are more common and can happen in most of the cases. The transient voice changes
 usually occurs because one or more of the nerves are irritated either by moving them out of
 the way during the dissection of thyroid gland or because of the inflammation or oedema that
 happens after the thyroid surgery.

 One of the indices of success in thyroid surgery is the frequency of complications. The most
 frequent postoperative complications following thyroidectomy are hypocalcemia and airway
 complications. These are life threatening and have a significant impact on quality of life .
 Airway complications may result from postoperative haematoma, vocal cord paralysis, laryngeal
 oedema, and tracheomalacia .

 Recurrent laryngeal nerve palsy (RLNP) is a rare but potentially catastrophic complication of
 thyroid surgery. Damage to a recurrent laryngeal nerve (RLN) with resultant paralysis of the
 sole abducting muscle (posterior cricoarytenoid) of the vocal folds can cause symptoms
 ranging from hoarseness in unilateral lesions to stridor and acute airway obstruction in
 bilateral damage. RLNP following thyroid surgery is one of the leading reasons for
 medico-legal litigation against surgeons .

 Injury of the laryngeal nerves may not be the only cause of voice changes. Other possible
 causes include injury of the prethyroid strap muscles and cricothyroid muscles or impairment
 of laryngotracheal movement due to wound contracture after surgical trauma of the soft
 tissues. A delicate surgical technique may prevent such complications, but it remains to be
 clarified whether voice alterations may occur after thyroidectomy without any laryngeal nerve
 injury. Computerized acoustic analysis of the patients undergoing thyroidectomy without
 laryngeal nerve injury may help determine possible voice changes objectively .

 Dysphagia is a typical symptom experinced preoperatively by patients with enlarged thyroid
 due to a direct compression of the swallowing organs. In these patients, uncomplicated
 thyroidectomy often leads to improvements in perceptions of swallowing function. However
 impaired swallowing and neck strangling frequently occur postoperatively. Intraoperative
 nerve injury regularly causes postoperative dysphagia, but dysphagia is also complained of
 after uncomplicated thyroidectomies. These symptoms are usually dismissed by the clinicians
 or attributed to orotracheal intubation. In many patients, correlations for these swallowing
 disorders cannot be found in objective test results. Reasons for dysphagia and esophageal
 motility changes after uncomplicated thyroidectomy could be injury of the perithyroidal
 neural plexus, changes in the laryngeal vascular supply, postoperative adhesions, decreased
 pressure of the upper esophageal sphincter, or changed position after thyroidectomy .

 Investigate non neurogenic causes of vocal and swallowing changes following thyroid surgery:
 Vocal cord immobility (VCI) is defined as various spectrum of motion impairment in the vocal
 cord. Although hoarseness is the main symptom in VCI, dysphonia, odynophonia, dysphagia,
 chronic cough, and laryngospasm can also occur. Visual inspection by a laryngoscopy and
 electrophysiologic study, such as laryngeal electromyography (LEMG) can help to differentiate
 the neurogenic and non-neurogenic causes of VCI. The LEMG technique was first introduced by
 Weddel et al., and needle electrode insertion in small muscles of larynx with assistance of
 laryngoscopy or in-surgery was first reported in 1950s, followed by the standardized
 percutaneous electrode insertion technique. LEMG is not only helpful in diagnosing
 neuromuscular disorder in the larynx, but it can also be used in botulinum toxin or
 hyaluronic acid injection in vocal cord. In the process of first diagnosing VCI, various
 systemic diseases can be suspected from the symptoms. Viral or bacterial infections can
 attribute to post-infectious neuropathies and a wide spectrum of malignancies or tumors
 present as a paralysis. Also, VCI can be seen in systematic neurologic diseases such as
 myasthenia gravis, Charcot-Marie-Tooth disease, and multiple sclerosis. With LEMG results, it
 aids to select other diagnostic tests and determine timing and type of treatments.
 Furthermore, LEMG results are useful in predicting negative outcomes and their findings can
 alter definitive treatments. It is important to diagnose VCI of neurogenic causes and to
 affect treatment and prognosis. However, there are few research studies regarding the
 association between the clinical characteristics in VCI and LEMG results .
Inclusion Criteria:

 -  benign and malignant thyroid disease normal voice controlled thyroid hormones level

 Exclusion Criteria:

 -  Age below 18 years any cardiac, renal,hepatic, respiratory, mental can interfere with
 the surgery any voice changes due to any cause before surgery previous head and neck
 surgery neurological dysfunctions