KTP-532 Laser Cordotomy for Bilateral Abductor Paralysis Produl Hazarika ~, Deepak Ranjan Nayak ~, R. Balakrishnan ~, Girish Raj 4, Kailesh Pujary s, Shahrayar Ali Mallick s
"Key Words : Bilateral abductor paralysis. Lateralization procedures. KTP-532 laser eordotomy.
INTRODUCTION Bilateral abductor paralysis can be caused by various pathologies which may be a surgical dilemma for the practising otolaryngologist. Commonest cause of bilateral abductor paralysis is accidental or iatrogenic trauma. A variety of surgical procedures including extralaryngeal and endoscopic approaches have been described with an objective of improving the laryngeal airway and thus favoring decannulation. However, these lateralization procedures may give rise to postoperative breathy, weak voice or an incompetent larynx.
rates [Ejnell, 1984] but patients were found to have only acceptable postoperative voice quality.
Tracheostomy still remains a highly effective mode of management of bilateral vocal cord paralysis [Dennis and Kashima, 1989], particularly in emergencies. However, this procedure is not acceptable for most of the patients. Procedures like excision of the entire vocal cord and ventricle [Jackson, 1922], submucous resection of the vocal cord [Hoover, 1932] extralaryngeal arytenoidectomy [King, 1939] etc., have been evaluated by various workers and found to beassociated with severe postoperative dysphonia. Woodman [1946] proposed an extralaryngeal approach for arytenoidectomy and suturing of vocal process to the inferior comu of the thyroid cartilage. This technique remained popular in the past but nearly 3040% of cases failed, necessitating the same procedure on the opposite side. Thornell [1948] advocated electrocautery assisted endoscopic arytenoidectomy for lateralization of one or both cords. Nerve-muscle pedicle reinnervation of the posterior cricoarytenoid muscle was described by Tucker [1976], but as his result could not be reproduced by majority of ENT surgeons, the technique lost its appeal. Ejnell's endoscopic lateralization of the vocal cord became popular in the recent past for its simplicity and good decannulation
37 cases of bilateral abductor palsy were treated between 1990 and 1999 at the Department of ENT-Head & Neck Surgery, Kasturba Medical College, Manipal. 17 cases underwent Woodman's procedure and 17 cases underwent endoscopic arytenoidectomy with or without membranous cord lateralization. Since September 1999, 3 cases underwent KTP-532 laser assisted posterior cordotomy. All except 8 cases were a sequelae of a thyroid surgery. Of the 8 nonthyroid cases, 4 resulted from accidental trauma, 2 due to tracheostomy and 2 were of idiopathic origin. All patients were evaluated by plain radiographs of the neck-lateral and the anteroposterior views, rigid telescopy and when coexistent laryngotracheal stenosis was suspected, they were in addition evaluated by CT imaging with or without 3D reconstruction [virtual endoscopy -Fig. I]. One patient was assessed by MR imaging. Those with coexistent laryngotracheal stenosis were not included in the study.
Laser assisted arytenoidectomy was described first by Ossaff [1983] who used CO2 laser. The use of KTP laser in the treatment of bilateral abductor palsy has not been well reported. This paper deals with our experience in the use of KTP-532 laser in bilateral abductor paralysis and its results have been compared with that of various other techniques performed in our department.
MATERIALS AND METHODS
Analysis of the efficacy of various non-laser procedures and KTP-532 laser cordotomy done at our institute was carried out in terms of decannulation rates, complications and voice
~Professorand Chief,ZAssociateProfessOr,3AssistantProfessor,4AssistantProfessor,5ClinicalFellow,6ClinicalFellow,Departmentof ENT-Head& Neck Surgery,KasturbaMedicalCollege,Manipal- 576 119,Kamataka,India.
KTP-532 Laser Cordotomy for Bilateral Abductor Paralysis
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quality. Objective pre and postoperative speech quality a s s e s s m e n t was done in laser c o r d o t o m y cases using computerized VAGMI diagnostic module.
mode. This step greatly facilitates the visualization of the true vocal cord and hence ensures a complete and precise cordotomy. Unlike in the previous reported cases [Dennis
Surgical technique o f KTP-532 laser cordotomy : All 3 patients had a tracheostoma and the operation was done under general anaesthesia. Endotracheal tubes protected by aluminium foil was used in 2 cases and a specially designed laser friendly endotracheal tube was used in one case. A suspension microlaryngoscope was introduced and stabilized in a position so as to expose the ventricular bands and the
and Kashima ; 1989, Manolopoulos et al. ; 1999] wherein a laser assisted wedge excision of the vocal cord anterior to the vocal process [posterior cordectomy] was made, we modified the technique to posterior cordotomy. After identifying the vocal process using a suction tip, the part of the vocal cord just anterior to it was precisely cut transversely including the entire vocalis and thyroarytenoid muscle, using the laser [Fig.III]. Care was taken to avoid injury to the vocal
vocal cords, saline soaked gauze was placed in the subglottis
process. Contraction and retraction of the vocalis muscle lead
to avoid laser injury. Using a Zeiss-OPM surgical microscope and Laserscope delivering KTP-532 laser through a 0.6 m m firbreoptic cable, the right false vocal cord was vaporized completely [fig. II] to visualize the ventricle (Manolopoulos et al., 1999). The laser was delivered at 8 watts, continuous
to a wedge shaped defect in the posterior cord, improving the glottic chink to about 5 m m [Fig.IV]. Postoperatively, the patients were given oral prednisolone in the dose of 25 mg three times a day for 5-6 days along with an antibiotic.
Fig. I : Virtual endoscopy of the larynx by 3D CT scan reconstruction [VC : vocal cord, AC : anterior commisure, TR : trachea]
Fig. Ill : Illustrations showing a) vaporizaion of the right vbentricular band [VB-shaded area] and the precise cordotomy [c] without wedge excision and b) the resultant improved airway due to the pull of the thyroarytenoid muscle [ A : arytenoid cartilage].
Fig. II : Vaporization of the right false cord to faciulitate exposure of the ventricle. Note the saline soaked gauze piece in the subglottis, placed to avoid laser injury. [ VC : vocal cord, VB : ventricular band].
Fig. IV: Improved glottic chink after laser cordotomy. [ C: laser cordotomy].
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KTP-532 Laser Cordotomyjbr Bilateral Abductor Paralysis
and the voice quality are given in table I. Though endoscopic lateralization with arytenoidectomy gave good results in terms of decannulation rates, the voice quality postoperatively in most cases was only acceptable. All 3 patients who underwent KTP-532 laser cordotomy could be decannulated and their postoperative voice quality was found to be good. The complications of the above procedures are compared in table I1. The speech analysis done using VAGMI parameters pre and post laser cordotomy is given in table IlI. The results demonstrate the superior role of KTP-532 laser cordotomy in preservation of the voice quality. Fig. V : Rigidtelescopicpiclure of the glottistaken 2 monthsfollowing laser cordotomy. Decannulation was done after l week and speech evaluation done after 1 month. Videoendoscopic evaluation and recording was also done during the postoperative followup [fig.V]. OBSERVATIONS AND RESULTS The lateralization techniques used, their decannulation rates
DISCUSSION The various surgical procedures that have been mentioned in the literature for the mangement of bilateral vocal cord paralysis show inconsistent results. At times, the same procedure may have to be repeated because of the inadequate airway and intolerance for decannulation. In cases where airway becomes adequate, patients' voice deteriorates in over 60% producing a severe voice disability. Woodman's
Table - 1 : Decannulation rates and the subjective voice quality following various lateralization procedures.
Lateralization procedure [n=37] 1. Woodman's procedure 2. Endoscopic arytenoidectomy 3. Endoscopic lateralization +aryteonoidectomy 4. KTP-532 laser cordotomy
No. of cases
Decannulation rate No. of Case [%]
good
Voice quality acceptable [subjective]
1o[59] 6 [75]
17 8
poor 11 3
9 [lOO]
3[100]
Table I! : Complications encountered in various lateralization procedures.
Complications
Woodman's Procedure [n=17]
Laterahzation Endoscopic arytenoidectomy
[n=8]
procedrue Endoscopic arytenoidectomy +Lateralization [n=9]
I. Laryngeal odema 2. Bleeding 3. Granuloma 4. Dysphagia 5. Delayed decannulation 6. Need for revision
Indian Journal q/Otolao'ngologl' and Head and Neck Surge O' Vol. 54 No. 3, Juh" - September 2002
KTP-532 laser surg. [n=3]
KTP-53 2 Laser Cordotomy for Bilateral Abductor Paralysis Table - III : Speech assessment done before and after KTP - 532 laser cordotomy using computerized VGMI diagnositc module.
Parameters 1. Mean Fo [Hz] 2. Flu/sec in Fo 3. Ext.fluc in Fo 4. Flu/sec in Int 5. Ext. Fluc in Int 6. H/N ratio 7. Jitter [To] (%) 8. Shimmer [dB] 9. S Fo [Hz]
Pre-treatment 137.2 8.5 3.4 0 0 24 1.5 0.4 152.3
Post treatment 152.8 9.6 6.2 4.1 3.3 21 4.1 0.8 169
extralaryngeal arytenoidectomy was performed earlier in our centre with poor results. About 40% needed revision surgery in the form of either same operation or an endoscopic arytenoidectomy on the opposite side. Dynamic lateralization procedures like Tucker's (1976) reinnervation of the posterior cricothyroid muscle by ansa hypoglossi nerve-muscle pedicle and Crumley's (1986) ansa hypoglossi/phrenic to recurrent laryngeal nerve anastomosis created lot of enthusiasm but did not become popular as the results were not reproducible. After Ejnell [1984] described the endoscopic lateralization for bilateral abductor paralysis, this technique gained wide popularity and became the treatment of choice, becasuse of its simplicity, good decannulation rates and minimal morbidity and hospitalization. However, the postoperative voice quality was only subjectively acceptable. Introduction of various lasers gave interesting turn in the management of laryngeal disorders. In 1983, Ossoff et al described endoscopic arytenoidectomy using CO., laser. This procedure was found to result in moderate to severe reductions in phonatory quality (Crumley, 1993). Potential complications included formation of granuloma formation of posterior glottic web, cricoid perichondritis etc (Ossoff et al, 1990). Dennis and Kashima (1989) described CO2 laser posterior cordectony with good results both in terms of decannulation and voice quality. Linder and Lindholm (1992) used CO2 laser to reduce the bulk of the fold and fibrin glue was used to maintain the lateral position. Crumley (1993) advocated endoscopic laser medial arytenoidectomy. The above procedures often relieved the airway at the expense of voice
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quality. Manolopopulos et al. (1999) modified the posterior cordectomy approach of Dennis and Kashima by vaporizing the false cord in addition to cordectomy using KTP-532 laser. When compared with the traditional techniques, the advantages offered by KTP-532 laser cordotomy are evident in its rapidity, simplicity in concept, immediate assessment of airway size, reliablility of the outcome, short hospitalization, low risk of complications and suitability of revision operation whenever necessary. KTP-532 laser has a wavelength in the visible region and is absorbed by pigments containing its complimentary colours such as hemoglobin and melanin. KTP-532 laser gives better hemostasis because of it's absorption by hemoglobin. The inherent advantage of the KTP-532 laser is fibreoptic flexible delivery system which is very handy and can be used easily. Conventional local complications like arytenoid odema, granuloma and scar formation are almost nil in KTP-532 laser surgery. Voice restortation after surgery is quite acceptable and can be reliably advised for professional voice users. This may be due to restoration of the arytenoids and most of the length of the vocal cord. This laser can be an effective tool to treat any coexistent subglottic/tracheal stenosis. The need for a skillful surgeon, and the cost of the equipment are the only inherent disadvantages of laser. Various complications have been reported following laser cordectomy like arytenoid perichondritis etc. [Ossoff et al., 1990]. However we did not experience the above complications with KTP-532 laser cordotomy. This may be best explained by precise cordotomy rather than cordectomy and selection of proper site of cordotomy avoiding injury to the vocal process. CONCLUSION KTP-532 laser cordotomy is a superior, viable and reliable alternative to the other lateralizaion procedures for bilateral abductor paralysis of the vocal cords. The distinct advantages of this technique is the better voice quality postoperatively, simplicity of the procedure and faster results with least morbidity. This preliminary series demonstrates the efficacy of KTP-532 laser cordotomy in terms of 100% decannulation rates, good postoperative voice quality and least complications. However, a larger series over a longer followup period will accurately evaluate the efficacy of this procedure.
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KTP-532 Laser Cordotomy for Bilateral Abductor Paralysis
REFERENCES
9.
1.
Crumley R. L. [1993] : Endoscopic laser medial arytenoidectomy for airway management in bilateral laryngeal paralysis. Annals of Otology Rhinology and Laryngology, 102 : 81-84.
2.
Dennis D. E and Kashima H. [1989] : Carbon dioxide laser posterior cordectomy for treatment of bilateral vocal cord paralysis Annals of Otology Rhinology and Laryngology, 98 : 930-934.
3.
Ejnell H., Bake B., Hallen O., et al. [1984] : A simple operation for bilateral vocal cord paralysis. Laryngoscope 94 : 954-958.
4.
Hoover W. B. [1932] : Bilateral abductor paralysis, operative treatment of submucus resection of the vocal cord. Archives of otolaryngology 15 : 337-355.
5.
Jackson C. [1922] : Ventriculocordectomy, a new operation for the cure of goitrous glottic stenosis. Archives of Surgery 4 : 257-254.
6.
King B. T. [1939] : A new and function restoring operation for bilateral abductor fold paralysis. Journal of American Medical Association 112 : 814-823.
7.
8.
Linder A., Lindholm C. E. [1992] : Vocal fold lateralization using carbon dioxide laser and fibrin glue. Journal of Laryngology and Otology 106 : 226-230. Manolopoulos L., Stavroulaki E, Yiotakis J., et al. [1999] : CO2 and KTP-532 laser cordectomy for bilateral vocal fold paralysis. The Journal of laryngology and Otology 113 : 637-641.
OssoffR. H., Duncavage J. A., Shapshay S. M., et al. [1990] : Endoscopic laser arytenoidectomy revisited. Annals of Otology Rhinology and Laryngology, 99 : 764-771.
10. Thornell W. C. [1948]**/- : Intralaryngeal approach for arytenoidectomy in bilateral abductor vocal cord paralysis. Archives of Otolaryngology 47:505-508. 11. Tucker H. M. [1976] : Human laryngeal reinnervation. Laryngoscope 86 : 769-799. 12. Woodman D. [1946] : A modification of the extralaryngeal approach to arytenoidectomy for bilateral abductor paralysis. Archives of Otolaryngology 43 : 63-65.
Address for Correspondence : Prof. E Hazarika Professor and Head Department of ENT-Head & Neck Surgery Kasturba Medical College M a n i p a l - 5 7 6 119, K a r n a t a k a India.
f
4th Practical Endoscopic Sinus Surgery Course With Hands on Cadaver-Dissection To be held at Northern Railway Central Hospital, Basant Lane, Connaught Place, New Delhi from 25th December to 27th December 2002. International Guest Faculty 9 Dr. S. K. Kaluskar, Tyronne County Hospital, Ireland, U.K. Limited seats for hands on cadaver on first come first served basis. Contact : Dr. Sanjay Sachdeva Sr. Consultant in ENT, Indraprastha Apollo Hospital, New Delhi. Course Director B- 163, Greater Kailash-I New Delhi - 110048 Tel : (011) 6467507; 6410855 E-mail:
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Indian Journal o f Otola~ngology and Head and Neck Surge~ Vol. 54 No. 3 July - September 2002
