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Cricopharyngeal myotomy in the management of neurogenic and muscular dysphagia
PERGAMON
Neuromuscular Disorders 7 Suppl. 1 (1997) $85-$89
Cricopharyngeal myotomy in the management of neurogenic and muscular dysphagia Andr6 Duranceau* Department of Surgery, Thoracic Surgery Program, Universit~ de Montreal, Hfitel-Dieu de Montreal, 3840, St-Urbain, Montreal, Quebec, H2W 1T8 Canada
Abstract
Oropharyngeal dysphagia results from disruption of the integrated mechanism of swallowing. Neurogenic dysphagia is caused by central nervous system disorders or by cranial nerve involvement and it may be distinguished from muscular dysphagia such as that seen mostly in oculopharyngeal muscular dystrophy (OPMD). Based on our 20-year experience in a university hospital thoracic surgery service, we describe the results of the clinical evaluation, the laboratory testing and the surgical management of a recent subgroup of patients experiencing dysphagia from neurogenic and muscular disorders. © 1997 Elsevier Science B.V.
Keywords: Neurogenic dysphagia; Muscular dysphagia; Oculopharyngeal muscular dystrophy; Cricopharyngeal myotomy; Pharyngeal emptying scintiscan
1. Introduction
2. Patients and methods
Muscular dysphagia as seen in oculopharyngeal muscular dystrophy (OPMD) and in some other forms of muscular disease is characterized by an impaired function of the pharyngeal muscles with weak and sluggish contractions. Although the upper esophageal sphincter (UES) may appear to be manometrically functional, it acts as a barrier to pharyngoesophageal transit since the powerless pharynx is unable to mount the proper contraction force that influences sphincter relaxation and pushes the bolus into the cervical esophagus [1-4]. Neurogenic dysphagia results from disruption of the swallowing mechanisms in central nervous system (CNS) diseases or cranial nerve involvement. Incoordination between pharyngeal contractions and UES relaxation is the most frequent observation in these patients [5,6], often resulting in misorientation of the swallowed bolus with pharyngooral and nasal regurgitations frequently associated with laryngotracheal aspirations. The aim of this work is to review our experience in the evaluation and the surgical management of patients with dysphagia from neurogenic and muscular disorders.
Over the last 20 years, 205 patients underwent a cricopharyngeal myotomy for oropharyngeal dysphagia of various etiologies in the Thoracic Surgery Service, H6tel-Dieu de Montr6al. From this patient population, a recent subgroup of 20 had neurologic diseases causing neurogenic dysphagia and were followed for a mean of 35 months after treatment (range: 10-120 months). The neurologic patient population (10 men, 10 women) were aged from 35 to 82 years. Their swallowing difficulties were the sequels of cerebrovascular accidents for fifteen of them (15/20), while one patient was classified into one of the following categories in succession: cerebral and cervical spine trauma; amyotrophic lateral sclerosis; Parkinson's disease; pseudobulbar palsy; post-intracranial surgery. From a larger group of 86 patients with pure muscular disease, a subgroup of 15 patients with OPMD (aged 62-73 years) were recently assessed from 9 to 14 months :after cricopharyngeal myotomy. For both groups of patients pre- and postoperative evaluation included assessment of symptoms, radiologic examination, motility studies of the pharyngoesophageal junction and a radionuclide pharyngeal emptying study. Through a specific questionnaire on dysphagia, the frequency of symptoms was graded before and after cricopharyngeal myotomy
* Corresponding author. Tel.: +1 514 8432611, ext. 4632; fax: +1 514 8432704.
0960-8966/97/$17.00 © 1997 Elsevier Science B.V. All rights reserved PI1 S 0 9 6 0 - 8 9 6 6 ( 9 7 ) 0 0 0 8 9 - 8
A. Duranceau / Neuromuscular Disorders 7 Suppl. 1 (1997) $85-$89
$86
Table 1 Muscular dysphagia (OPMD) relative frequency of symptoms Symptoms
Preoperativea
\
Postoperativea P value
\\ \
Dysphagia To solids To liquids Regurgitations Pharyngooral Pharyngonasal Aspirations During meal During sleep Alimentary incarceration Coughing Bronchorrhea
\ \
2.8 + 0.4 2.2 _+0.9
0.7 + 0.8 0.5 _+0.6
0.003 0.002
1.9 + 1.0 1.9 + 1.2
0.6 _+0.5 0.3 _+0.5
0.01 0.002
2.4 + 0.9 1.8 + 1.1 2.5 + 0.8 2.1 + 1.1 2.1 + 1.0
0.5 + 0.7 0.4 + 0.5 0.6 + 0.7 0.5 + 0.7 0.6 + 0.8
0.004 0.008 0.002 0.01 0.004
aMean and one standard deviation from a frequency scale where: O, never; 1, rarely; 2, sometimes; 3, frequently. as: 0, never; 1, rarely; 2, sometimes; 3, frequently. The list of the symptoms so evaluated is found in Table 1.
2.1. Operation All patients underwent cricopharyngeal m y o t o m y using a standardized technique [7,8]. The approach is through a left cervical oblique incision along the anteromedial border of the sternocleidomastoid muscle. The posterior pharyngoesophageal junction is individualized and a no. 36 mercury bougie placed in the esophagus and used as a stent. A 6-cm myotomy is performed f r o m hypopharynx to cervical esophagus and a flap of muscle is dissected free from the mucosa, to be resected for subsequent histological analysis (Fig. 1). Patients are allowed a liquid diet the day after the operation and usually discharged the 3rd day following myotomy.
f~ I "\ \ \ \ \\
\
Fig. 1. Cricopharyngeal myotomy for neurogenic and muscular oropharyngeal dysphagia: the approach is through a left cervical oblique incision and a flap of muscle is dissected free from the esophageal mucosa. as well as percentage of full relaxation and coordination of the sphincter are recorded during 10 voluntary deglutitions. These values (shown in Tables 2 and 3) were expressed as mean compared before and after the operation.
2.4. Radionuclide pharyngeal emptying study Eight of the patients with neurologic diseases and the 15 patients with OPMD were given a single 10-15-cc water bolus tagged with 1.0 m Ci of 99mTcsulfur colloid. Both analog and digital acquisition of the radioactivity were started simultaneously for a total duration of 15 min. Studies were performed in the upright and supine positions and time activity histograms were obtained.
2.5. Statistical analysis 2.2. Radiology Standard six frames/s barium esophagrams were obtained under fluoroscopic control for both groups of patients. Observation of voluntary deglutition, swallowing apraxia or hesitation, pharyngeal stasis, functional obstruction and incoordination of the upper esophageal sphincter were recorded.
2.3. Manometry
Results of motility studies are expressed as mean + one standard deviation, and median values are used for radionuclide pharyngeal emptying studies. Statistical analysis of manometric and radionuclide studies was performed with the non-parametric Wilcoxon rank sum test. A two-tailed Student's test for paired values and ×2 analysis for discon-
Table 2 Muscular dysphagia (OPMD) manometry (n = 15)
Manometric recordings were obtained before and after the operation using a perfused system with a stationary recording o f the pharyngoesophageal junction [6]. A fourlumen catheter with each lumen ending as a lateral port oriented at 90 ° from each other is perfused by a pneumohydraulic pump generating a pressure of 15 PSI The proximal port is positioned in the pharynx, the second records the high pressure zone and the last two orifices are located in the cervical esophagus. Mean values for peak pharyngeal contractions, resting and closing pressures in the sphincter
Pharyngeal peak contraction pressure (mm Hg) Upper esophageal sphincter Resting pressure (mm Hg) Contraction pressure (mm HG) Relaxation time (s) Coordination (%)
Preoperative
Postoperative P value
10.1 + 4.5
10.0 + 1.8
NS
34.4 + 13.4
15.7 + 8.9
0.0005
60.1 + 27.7
28.2 + 13.6
0.001
1.6 + 0.5 89.0 + 14.9
1.2 + 0.2 78.0 + 30.8
0.01 NS
A. Duranceau /Neuromuscular Disorders 7 Suppl. 1 (19971 $85-$89
tinuous values were used when appropriate. A P value of less than 0.05 was considered significant.
3.
Results
3.1. Symptoms Symptoms of dysphagia before and after cricopharyngeal myotomy are presented in Table 1 for OPMD patients. When looking at the relative frequency of symptoms, patients with muscular dysphagia show a significant improvement in their clinical status during the immediate period after the myotomy. In patients with neurogenic dysphagia, although improved, most of the symptoms may persist to a certain degree. In fact, the only significant improvement for patients with neurogenic dysphagia after myotomy is Normal Subject activity
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.... Time ( seconds)
,,
( A ~ XRaclionuclide segmental emptying eRedionuclide pharyngeal clearance
$87
Table 3 Neurogenic dysphagia manometry (n = 20)
Pharyngeal peak contraction pressure (mm Hg) Upper esophageal sphincter Resting pressure (mm Hg) Contraction pressure (mm Hg) Relaxation time (s) Coordination (%)
Preoperative
Postoperative
P value
21.4+_ 11
18.9+_ 11.6
NS
52.4 + 35
22.8 +- 17
0.0l
73.9 +- 40.4
40.3 __+31.3
NS
1.8 + 1.0 0.2 _+ 0.8
1.2 +__0.4 0.1 +- 0.2
0.04 NS
seen in a reduction in the frequency of aspiration episodes while eating (P < 0.03). 3.2. Radiology Radiologic findings for OPMD patients before myotomy were similar to those already published [1]. Although these patients all retain adequate voluntary deglutition, pharyngeal hypomobility is observed with stasis of radioopaque material in the valleculae and pyriform sinuses in 14/15 cases (93%). A cricopharyngeal bar was seen at the UES level in 12/15 cases (80%), two of these patients presenting a complete obstruction. Laryngeal penetration and tracheal aspiration were diagnosed in 9/15 cases (60%). For patients with neurogenic dysphagia, although there is improvement in symptoms, laryngeal penetration and tracheal soilage is seen frequently and all radiologic signs of muscle group dysfunction (apraxia, epiglottic incoordination, stasis and aspirations) persist despite the myotomy. In both categories of patients, the functional obstruction caused by the upper esophageal sphincter is significantly decreased by the myotomy. 3.3. Manometry
Oculopharyngeal ,Muscular Dystrophy activity(%) pharynx 2S o +
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3.4. Radionuclide studies
IS
8gUS
=s
Manometric findings are described in Table 2 and Table 3. In OPMD patients, cricopharyngeal myotomy does not affect the hypotonicity of the pharynx, but the upper esophageal sphincter is significantly modified in its resting and closing pressures and the relaxation period is shortened. In a similar fashion, for other neurogenic dysphagia patients submitted to myotomy, resting pressures of the UES area are significantly decreased as well as the relaxation time.
+o
Timelseconds)
Fig. 2. (A) Radionuclide studies: normal emptying of the pharynx and esophagus in upright position. (B) Radionuclide studies: pharyngeal emptying is much delayed in oculopharyngeal muscular dystrophy.
Pharyngeal emptying scintiscan results are illustrated in Fig. 2A and B, and reported in Table 4. For OPMD patients, cricopharyngeal myotomy improves the pharyngeal emptying of the liquid bolus particularly in the supine position: pharyngeal stasis at 15 min decreases significantly in this position. Nevertheless, in the upright position, early clearing of the bolus (25% and 50%) is improved but pharyngeal
$88
A. Duranceau / Neuromuscular Disorders 7 Suppl. 1 (1997) $85-$89
Table 4 Muscular dysphagia (OPMD)pharyngealemptyingscintigram
Supine position Stasis at 15 min Upright position Stasis at 15 min
Pharyngeal Preoperclearance ative (s) f%)
Postoperative (s)
P value
25 50 75
0.9 2.0 7.0 6% 0.6 1.2 5.8 10.5%
0.04 0.005 0.02 0.01 0.02 0.07 NS NS
25 50 75
1.2 4.2 15.0 10.3% 0.9 2.1 6.O 14.8%
stasis is unchanged at 15 min. For patients with dysphagia caused by other neurogenic disorders pharyngeal emptying of a 10-cc liquid bolus is unchanged by myotomy.
4. Discussion Oropharyngeal dysphagia from muscular and other neurologic disorders results from distinct abnormalities having their basis in the pathology of their respective conditions. The investigative approach to the proximal dysphagia patient includes symptom assessment, coupled with videoradiology to delimit the anatomic and functional abnormalities of specific muscle groups at the pharyngoesophageal junction. Accurate manometric recording of the pharynx and upper esophageal sphincter is difficult to obtain. Modem motility techniques [4] using solid state transducers are considered to be more precise when trying to correlate symptoms and videoradiology with physiologic information. Radionuclide pharyngeal emptying studies [9] add quantitation to the findings obtained with the other methods. Endoscopic evaluation is used to rule out endoluminal lesions. Neurogenic dysphagia is caused by brain or cranial nerve damage. Stroke is probably the most common neurologic cause of this symptom. Severity of presentation is influenced by the extent of damage. While swallowing is considered normal in 86% of stroke patients 2 weeks after a unilateral accident [10], bihemispheric damage results in more significant and lasting swallowing difficulties [11]. Cerebrovascular accident patients affected by a dysphagia with intact voluntary deglutition more than 6 months after the vascular event, show an 80% chance of being clinically improved by a cricopharyngeal myotomy [5]. Failure to improve dysphagia results in continued aspiration and pulmonary sepsis; an increase in morbidity and mortality is seen in these patients. Motoneurone disease results mostly in oral phase dysfunction. Muscles of the tongue and pharynx show progressive signs of denervation with paresis, atrophy, fasciculations and occasionally complete loss of voluntary deglutition. Cricopharyngeal myotomy does not help these
patients consistently since the myotomy affects mostly the pharyngeal phase of deglutition, leaving the oral phase abnormalities untouched. The surgical literature [12,13] reports that 50% of the amyotrophic lateral sclerosis patients are improved at 6 months after myotomy with an operative mortality as high as 20%. Parkinson's disease, trauma or brain stem compression patients have also been treated by cricopharyngeal myotomy with variable results on their dysphagia. Overall, in the 242 cricopharyngeal myotomies reported [6], satisfactory to excellent clinical results are obtained in over 50% of treated patients. An intact voluntary deglutition, adequate antepulsion and retropulsion of the tongue, normal phonation and absence of dysarthria are considered conditions favoring an excellent prognosis. Dysphagia from muscular diseases was treated by cricopharyngeal myotomy since the early 1960's. Montgomery and Lynch [14], in 1971, contributed their early surgical experience with OPMD patients. Since then, over 100 patients with this condition have been reported in the literature. OPMD patients retain intact voluntary deglutition. They show no CNS or cranial nerve damage. While retaining all voluntary movements, they loose the propulsion force in their pharynx. In this situation, the cricopharyngeus, which is infiltrated with the same dystrophic process, becomes a functional obstruction to food transit by not responding to a powerless pharyngeal contraction. The most accurate manometric values on OPMD patients reported to this date are those of Castell et al. [6]. Using solid state transducers, these authors have documented low pharyngeal pressures corresponding to prolonged pharyngeal contractions and an associated incoordination between pharyngeal contraction and UES relaxation. Over 25% of patients show an abnormal relaxation with an increased residual pressure and an abnormal relaxation duration. There is a correlation between the severity of symptoms and the functional alterations in the pharynx and the esophagus. Cricopharyngeal myotomy is a well established technique used to help patients with oropharyngeal dysphagia. It is technically simple, involves a short hospital stay, carries minimal morbidity and is actually the only well documented treatment to help patients with this type of dysphagia. Medication and dilatation management have not been documented, to this day, as satisfactory alternatives to the surgical approach. In the short term, cricopharyngeal myotomy improves symptoms in 75% of patients with OPMD. This improvement correlates with a significant decrease in the resting pressures at the upper esophageal sphincter level and a decrease in the relaxation period of the sphincter. From preliminary observations, this improvement persist over the years. Reappearance of symptoms in time is seen with progression of the muscle dystrophy. Progressive loss of phonation is seen as a negative prognostic factor where laryngeal tensor muscles involved in the dystrophic process
A. Duranceau /Neuromuscular Disorders 7 Suppl. 1 (1997) $85-$89
cause loss of control of the laryngeal protection mechanisms allowing constant bouts of aspiration. Although the clinical improvement is less impressive, the neurogenic dysphagia patients show a similar physiological response to cricopharyngeal myotomy. The decrease in resting pressures of the sphincter with a decrease in the relaxation period suggests a decreased resistance to bolus transit. Selection of patients remains the first step to success in the management of dysphagia. The objectivity of the investigation process, as described here, helps to understand the underlying pathology and to improve the selection process. Improvement after cricopharyngeal m y o t o m y is expected if the following preoperative criteria are fulfilled, regardless of the nature of the lesions (neurogenic or muscular): (a) normal voluntary deglutition; (b) adequate tongue movement; (c) intact laryngeal function and phonation; and (d) absence of dysarthria. Finally, laryngeal excision with permanent tracheostomy and extensive cricopharyngeal m y o t o m y can be considered in patients with severe laryngeal dysfunction, repeated aspiration pneumonias and no anticipated improvement.
References [1] Duranceau AC, Letendre J, Clermont RJ, L6vesque HP, Barbeau A. Oropharyngeal dysphagia in patients with oculopharyngeal muscular dystrophy. Can J Surg 1978;21:326-329. [2] Duranceau AD, Beauchamp G, Jamieson GG, Barbeau A. Orophar-
$89
yngeal dysphagia and oculopharyngeal muscular dystrophy. Surg Clin North Am 1983;63:825-832. [3] Topart P, Deschamps C, Taillefer R, Duranceau A. Esophageal function in oculopharyngealmuscular dystrophy. Gullet 1992;2:149-154. [4] Castell JA, Castell DO, Duranceau A, Topart P. Manometric characteristics of the pharynx, upper esophageal sphincter, esophagus and lower esophageal sphincter in patients with oculopharyngeal muscular dystrophy. Dysphagia 1995;10:22-26. [5] Poirier NC, Taillefer R, Duranceau A. Cricopharyngealmyotomy for neurologic dysphagia. In: Bremner CG, De Meester TR, Peracchia A, editors. Modem approach to benign esophageal disease. St Louis: Quality Medical, 1995:155-164. [6] Duranceau A. Pha~ngeal and cricopharyngeal disorders. In: Pearson FG, editor. Esophageal surgery. New York: Churchill Livingstone, 1995:389-415. [7] Duranceau AC, Forand M, Fauteux JP. Surgery in oculopharyngeal muscular dystrophy. Am J Surg 1980;139:32-39. [8] Duranceau AC, Jamieson GG, Beauchamp G. The technique of cricopharyngeal myotomy. Surg Clin North Am 1983;63:833-839. [9] Taillefer R, Duranceau AC. Manometric and radionuclide assessment of pharyngeal emptying before and after cricopharyngeal myotomy in patients with OPMD. J Thorac Cardiovasc Surg 1988;95:868-875. [10] Meadows JC. Dysphagia in unilateral cerebral lesions. J Neurol Neurosurg Psychiatr 1973;36:853-860. [11] Gordon C, Langton Hewer R, Wade DT. Dysphagia in acute stroke. Br Med J 1987;295:411-414. [12] Lebo CP, U KS, Norris FH. Cricopharyngeal myotomy in amyotrophic lateral sclerosis. Laryngoscope 1976;86:862-868. [13] Loizou LA, Small M, Dalton GA. Cricopharyngeal myotomy in motor neuron disease. J Neurol Neurosurg Psychiatry 1980;43:4245. [14] Montgomery WW, Lynch JP. Oculopharyngeal muscular dystrophy treated by inferior constrictor myotomy. Trans Am Acad Ophthalmol Otolaryngol 1971;75:986-993.
Neuromuscular Disorders 7 Suppl. 1 (1997) $85-$89
Cricopharyngeal myotomy in the management of neurogenic and muscular dysphagia Andr6 Duranceau* Department of Surgery, Thoracic Surgery Program, Universit~ de Montreal, Hfitel-Dieu de Montreal, 3840, St-Urbain, Montreal, Quebec, H2W 1T8 Canada
Abstract
Oropharyngeal dysphagia results from disruption of the integrated mechanism of swallowing. Neurogenic dysphagia is caused by central nervous system disorders or by cranial nerve involvement and it may be distinguished from muscular dysphagia such as that seen mostly in oculopharyngeal muscular dystrophy (OPMD). Based on our 20-year experience in a university hospital thoracic surgery service, we describe the results of the clinical evaluation, the laboratory testing and the surgical management of a recent subgroup of patients experiencing dysphagia from neurogenic and muscular disorders. © 1997 Elsevier Science B.V.
Keywords: Neurogenic dysphagia; Muscular dysphagia; Oculopharyngeal muscular dystrophy; Cricopharyngeal myotomy; Pharyngeal emptying scintiscan
1. Introduction
2. Patients and methods
Muscular dysphagia as seen in oculopharyngeal muscular dystrophy (OPMD) and in some other forms of muscular disease is characterized by an impaired function of the pharyngeal muscles with weak and sluggish contractions. Although the upper esophageal sphincter (UES) may appear to be manometrically functional, it acts as a barrier to pharyngoesophageal transit since the powerless pharynx is unable to mount the proper contraction force that influences sphincter relaxation and pushes the bolus into the cervical esophagus [1-4]. Neurogenic dysphagia results from disruption of the swallowing mechanisms in central nervous system (CNS) diseases or cranial nerve involvement. Incoordination between pharyngeal contractions and UES relaxation is the most frequent observation in these patients [5,6], often resulting in misorientation of the swallowed bolus with pharyngooral and nasal regurgitations frequently associated with laryngotracheal aspirations. The aim of this work is to review our experience in the evaluation and the surgical management of patients with dysphagia from neurogenic and muscular disorders.
Over the last 20 years, 205 patients underwent a cricopharyngeal myotomy for oropharyngeal dysphagia of various etiologies in the Thoracic Surgery Service, H6tel-Dieu de Montr6al. From this patient population, a recent subgroup of 20 had neurologic diseases causing neurogenic dysphagia and were followed for a mean of 35 months after treatment (range: 10-120 months). The neurologic patient population (10 men, 10 women) were aged from 35 to 82 years. Their swallowing difficulties were the sequels of cerebrovascular accidents for fifteen of them (15/20), while one patient was classified into one of the following categories in succession: cerebral and cervical spine trauma; amyotrophic lateral sclerosis; Parkinson's disease; pseudobulbar palsy; post-intracranial surgery. From a larger group of 86 patients with pure muscular disease, a subgroup of 15 patients with OPMD (aged 62-73 years) were recently assessed from 9 to 14 months :after cricopharyngeal myotomy. For both groups of patients pre- and postoperative evaluation included assessment of symptoms, radiologic examination, motility studies of the pharyngoesophageal junction and a radionuclide pharyngeal emptying study. Through a specific questionnaire on dysphagia, the frequency of symptoms was graded before and after cricopharyngeal myotomy
* Corresponding author. Tel.: +1 514 8432611, ext. 4632; fax: +1 514 8432704.
0960-8966/97/$17.00 © 1997 Elsevier Science B.V. All rights reserved PI1 S 0 9 6 0 - 8 9 6 6 ( 9 7 ) 0 0 0 8 9 - 8
A. Duranceau / Neuromuscular Disorders 7 Suppl. 1 (1997) $85-$89
$86
Table 1 Muscular dysphagia (OPMD) relative frequency of symptoms Symptoms
Preoperativea
\
Postoperativea P value
\\ \
Dysphagia To solids To liquids Regurgitations Pharyngooral Pharyngonasal Aspirations During meal During sleep Alimentary incarceration Coughing Bronchorrhea
\ \
2.8 + 0.4 2.2 _+0.9
0.7 + 0.8 0.5 _+0.6
0.003 0.002
1.9 + 1.0 1.9 + 1.2
0.6 _+0.5 0.3 _+0.5
0.01 0.002
2.4 + 0.9 1.8 + 1.1 2.5 + 0.8 2.1 + 1.1 2.1 + 1.0
0.5 + 0.7 0.4 + 0.5 0.6 + 0.7 0.5 + 0.7 0.6 + 0.8
0.004 0.008 0.002 0.01 0.004
aMean and one standard deviation from a frequency scale where: O, never; 1, rarely; 2, sometimes; 3, frequently. as: 0, never; 1, rarely; 2, sometimes; 3, frequently. The list of the symptoms so evaluated is found in Table 1.
2.1. Operation All patients underwent cricopharyngeal m y o t o m y using a standardized technique [7,8]. The approach is through a left cervical oblique incision along the anteromedial border of the sternocleidomastoid muscle. The posterior pharyngoesophageal junction is individualized and a no. 36 mercury bougie placed in the esophagus and used as a stent. A 6-cm myotomy is performed f r o m hypopharynx to cervical esophagus and a flap of muscle is dissected free from the mucosa, to be resected for subsequent histological analysis (Fig. 1). Patients are allowed a liquid diet the day after the operation and usually discharged the 3rd day following myotomy.
f~ I "\ \ \ \ \\
\
Fig. 1. Cricopharyngeal myotomy for neurogenic and muscular oropharyngeal dysphagia: the approach is through a left cervical oblique incision and a flap of muscle is dissected free from the esophageal mucosa. as well as percentage of full relaxation and coordination of the sphincter are recorded during 10 voluntary deglutitions. These values (shown in Tables 2 and 3) were expressed as mean compared before and after the operation.
2.4. Radionuclide pharyngeal emptying study Eight of the patients with neurologic diseases and the 15 patients with OPMD were given a single 10-15-cc water bolus tagged with 1.0 m Ci of 99mTcsulfur colloid. Both analog and digital acquisition of the radioactivity were started simultaneously for a total duration of 15 min. Studies were performed in the upright and supine positions and time activity histograms were obtained.
2.5. Statistical analysis 2.2. Radiology Standard six frames/s barium esophagrams were obtained under fluoroscopic control for both groups of patients. Observation of voluntary deglutition, swallowing apraxia or hesitation, pharyngeal stasis, functional obstruction and incoordination of the upper esophageal sphincter were recorded.
2.3. Manometry
Results of motility studies are expressed as mean + one standard deviation, and median values are used for radionuclide pharyngeal emptying studies. Statistical analysis of manometric and radionuclide studies was performed with the non-parametric Wilcoxon rank sum test. A two-tailed Student's test for paired values and ×2 analysis for discon-
Table 2 Muscular dysphagia (OPMD) manometry (n = 15)
Manometric recordings were obtained before and after the operation using a perfused system with a stationary recording o f the pharyngoesophageal junction [6]. A fourlumen catheter with each lumen ending as a lateral port oriented at 90 ° from each other is perfused by a pneumohydraulic pump generating a pressure of 15 PSI The proximal port is positioned in the pharynx, the second records the high pressure zone and the last two orifices are located in the cervical esophagus. Mean values for peak pharyngeal contractions, resting and closing pressures in the sphincter
Pharyngeal peak contraction pressure (mm Hg) Upper esophageal sphincter Resting pressure (mm Hg) Contraction pressure (mm HG) Relaxation time (s) Coordination (%)
Preoperative
Postoperative P value
10.1 + 4.5
10.0 + 1.8
NS
34.4 + 13.4
15.7 + 8.9
0.0005
60.1 + 27.7
28.2 + 13.6
0.001
1.6 + 0.5 89.0 + 14.9
1.2 + 0.2 78.0 + 30.8
0.01 NS
A. Duranceau /Neuromuscular Disorders 7 Suppl. 1 (19971 $85-$89
tinuous values were used when appropriate. A P value of less than 0.05 was considered significant.
3.
Results
3.1. Symptoms Symptoms of dysphagia before and after cricopharyngeal myotomy are presented in Table 1 for OPMD patients. When looking at the relative frequency of symptoms, patients with muscular dysphagia show a significant improvement in their clinical status during the immediate period after the myotomy. In patients with neurogenic dysphagia, although improved, most of the symptoms may persist to a certain degree. In fact, the only significant improvement for patients with neurogenic dysphagia after myotomy is Normal Subject activity
(%) n
so
~e
pharynx
2S
* "'
....
' ' I
IL
,~. . . . .
,I
proximal esophagus
=s
o
•
'
'
I s
T
. . . .
s~
'
~
'
'
'
11
iatal esophagus
=s
reesophagus
~
:!/,+,
,<)-,...
.... Time ( seconds)
,,
( A ~ XRaclionuclide segmental emptying eRedionuclide pharyngeal clearance
$87
Table 3 Neurogenic dysphagia manometry (n = 20)
Pharyngeal peak contraction pressure (mm Hg) Upper esophageal sphincter Resting pressure (mm Hg) Contraction pressure (mm Hg) Relaxation time (s) Coordination (%)
Preoperative
Postoperative
P value
21.4+_ 11
18.9+_ 11.6
NS
52.4 + 35
22.8 +- 17
0.0l
73.9 +- 40.4
40.3 __+31.3
NS
1.8 + 1.0 0.2 _+ 0.8
1.2 +__0.4 0.1 +- 0.2
0.04 NS
seen in a reduction in the frequency of aspiration episodes while eating (P < 0.03). 3.2. Radiology Radiologic findings for OPMD patients before myotomy were similar to those already published [1]. Although these patients all retain adequate voluntary deglutition, pharyngeal hypomobility is observed with stasis of radioopaque material in the valleculae and pyriform sinuses in 14/15 cases (93%). A cricopharyngeal bar was seen at the UES level in 12/15 cases (80%), two of these patients presenting a complete obstruction. Laryngeal penetration and tracheal aspiration were diagnosed in 9/15 cases (60%). For patients with neurogenic dysphagia, although there is improvement in symptoms, laryngeal penetration and tracheal soilage is seen frequently and all radiologic signs of muscle group dysfunction (apraxia, epiglottic incoordination, stasis and aspirations) persist despite the myotomy. In both categories of patients, the functional obstruction caused by the upper esophageal sphincter is significantly decreased by the myotomy. 3.3. Manometry
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Manometric findings are described in Table 2 and Table 3. In OPMD patients, cricopharyngeal myotomy does not affect the hypotonicity of the pharynx, but the upper esophageal sphincter is significantly modified in its resting and closing pressures and the relaxation period is shortened. In a similar fashion, for other neurogenic dysphagia patients submitted to myotomy, resting pressures of the UES area are significantly decreased as well as the relaxation time.
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Fig. 2. (A) Radionuclide studies: normal emptying of the pharynx and esophagus in upright position. (B) Radionuclide studies: pharyngeal emptying is much delayed in oculopharyngeal muscular dystrophy.
Pharyngeal emptying scintiscan results are illustrated in Fig. 2A and B, and reported in Table 4. For OPMD patients, cricopharyngeal myotomy improves the pharyngeal emptying of the liquid bolus particularly in the supine position: pharyngeal stasis at 15 min decreases significantly in this position. Nevertheless, in the upright position, early clearing of the bolus (25% and 50%) is improved but pharyngeal
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Table 4 Muscular dysphagia (OPMD)pharyngealemptyingscintigram
Supine position Stasis at 15 min Upright position Stasis at 15 min
Pharyngeal Preoperclearance ative (s) f%)
Postoperative (s)
P value
25 50 75
0.9 2.0 7.0 6% 0.6 1.2 5.8 10.5%
0.04 0.005 0.02 0.01 0.02 0.07 NS NS
25 50 75
1.2 4.2 15.0 10.3% 0.9 2.1 6.O 14.8%
stasis is unchanged at 15 min. For patients with dysphagia caused by other neurogenic disorders pharyngeal emptying of a 10-cc liquid bolus is unchanged by myotomy.
4. Discussion Oropharyngeal dysphagia from muscular and other neurologic disorders results from distinct abnormalities having their basis in the pathology of their respective conditions. The investigative approach to the proximal dysphagia patient includes symptom assessment, coupled with videoradiology to delimit the anatomic and functional abnormalities of specific muscle groups at the pharyngoesophageal junction. Accurate manometric recording of the pharynx and upper esophageal sphincter is difficult to obtain. Modem motility techniques [4] using solid state transducers are considered to be more precise when trying to correlate symptoms and videoradiology with physiologic information. Radionuclide pharyngeal emptying studies [9] add quantitation to the findings obtained with the other methods. Endoscopic evaluation is used to rule out endoluminal lesions. Neurogenic dysphagia is caused by brain or cranial nerve damage. Stroke is probably the most common neurologic cause of this symptom. Severity of presentation is influenced by the extent of damage. While swallowing is considered normal in 86% of stroke patients 2 weeks after a unilateral accident [10], bihemispheric damage results in more significant and lasting swallowing difficulties [11]. Cerebrovascular accident patients affected by a dysphagia with intact voluntary deglutition more than 6 months after the vascular event, show an 80% chance of being clinically improved by a cricopharyngeal myotomy [5]. Failure to improve dysphagia results in continued aspiration and pulmonary sepsis; an increase in morbidity and mortality is seen in these patients. Motoneurone disease results mostly in oral phase dysfunction. Muscles of the tongue and pharynx show progressive signs of denervation with paresis, atrophy, fasciculations and occasionally complete loss of voluntary deglutition. Cricopharyngeal myotomy does not help these
patients consistently since the myotomy affects mostly the pharyngeal phase of deglutition, leaving the oral phase abnormalities untouched. The surgical literature [12,13] reports that 50% of the amyotrophic lateral sclerosis patients are improved at 6 months after myotomy with an operative mortality as high as 20%. Parkinson's disease, trauma or brain stem compression patients have also been treated by cricopharyngeal myotomy with variable results on their dysphagia. Overall, in the 242 cricopharyngeal myotomies reported [6], satisfactory to excellent clinical results are obtained in over 50% of treated patients. An intact voluntary deglutition, adequate antepulsion and retropulsion of the tongue, normal phonation and absence of dysarthria are considered conditions favoring an excellent prognosis. Dysphagia from muscular diseases was treated by cricopharyngeal myotomy since the early 1960's. Montgomery and Lynch [14], in 1971, contributed their early surgical experience with OPMD patients. Since then, over 100 patients with this condition have been reported in the literature. OPMD patients retain intact voluntary deglutition. They show no CNS or cranial nerve damage. While retaining all voluntary movements, they loose the propulsion force in their pharynx. In this situation, the cricopharyngeus, which is infiltrated with the same dystrophic process, becomes a functional obstruction to food transit by not responding to a powerless pharyngeal contraction. The most accurate manometric values on OPMD patients reported to this date are those of Castell et al. [6]. Using solid state transducers, these authors have documented low pharyngeal pressures corresponding to prolonged pharyngeal contractions and an associated incoordination between pharyngeal contraction and UES relaxation. Over 25% of patients show an abnormal relaxation with an increased residual pressure and an abnormal relaxation duration. There is a correlation between the severity of symptoms and the functional alterations in the pharynx and the esophagus. Cricopharyngeal myotomy is a well established technique used to help patients with oropharyngeal dysphagia. It is technically simple, involves a short hospital stay, carries minimal morbidity and is actually the only well documented treatment to help patients with this type of dysphagia. Medication and dilatation management have not been documented, to this day, as satisfactory alternatives to the surgical approach. In the short term, cricopharyngeal myotomy improves symptoms in 75% of patients with OPMD. This improvement correlates with a significant decrease in the resting pressures at the upper esophageal sphincter level and a decrease in the relaxation period of the sphincter. From preliminary observations, this improvement persist over the years. Reappearance of symptoms in time is seen with progression of the muscle dystrophy. Progressive loss of phonation is seen as a negative prognostic factor where laryngeal tensor muscles involved in the dystrophic process
A. Duranceau /Neuromuscular Disorders 7 Suppl. 1 (1997) $85-$89
cause loss of control of the laryngeal protection mechanisms allowing constant bouts of aspiration. Although the clinical improvement is less impressive, the neurogenic dysphagia patients show a similar physiological response to cricopharyngeal myotomy. The decrease in resting pressures of the sphincter with a decrease in the relaxation period suggests a decreased resistance to bolus transit. Selection of patients remains the first step to success in the management of dysphagia. The objectivity of the investigation process, as described here, helps to understand the underlying pathology and to improve the selection process. Improvement after cricopharyngeal m y o t o m y is expected if the following preoperative criteria are fulfilled, regardless of the nature of the lesions (neurogenic or muscular): (a) normal voluntary deglutition; (b) adequate tongue movement; (c) intact laryngeal function and phonation; and (d) absence of dysarthria. Finally, laryngeal excision with permanent tracheostomy and extensive cricopharyngeal m y o t o m y can be considered in patients with severe laryngeal dysfunction, repeated aspiration pneumonias and no anticipated improvement.
References [1] Duranceau AC, Letendre J, Clermont RJ, L6vesque HP, Barbeau A. Oropharyngeal dysphagia in patients with oculopharyngeal muscular dystrophy. Can J Surg 1978;21:326-329. [2] Duranceau AD, Beauchamp G, Jamieson GG, Barbeau A. Orophar-
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yngeal dysphagia and oculopharyngeal muscular dystrophy. Surg Clin North Am 1983;63:825-832. [3] Topart P, Deschamps C, Taillefer R, Duranceau A. Esophageal function in oculopharyngealmuscular dystrophy. Gullet 1992;2:149-154. [4] Castell JA, Castell DO, Duranceau A, Topart P. Manometric characteristics of the pharynx, upper esophageal sphincter, esophagus and lower esophageal sphincter in patients with oculopharyngeal muscular dystrophy. Dysphagia 1995;10:22-26. [5] Poirier NC, Taillefer R, Duranceau A. Cricopharyngealmyotomy for neurologic dysphagia. In: Bremner CG, De Meester TR, Peracchia A, editors. Modem approach to benign esophageal disease. St Louis: Quality Medical, 1995:155-164. [6] Duranceau A. Pha~ngeal and cricopharyngeal disorders. In: Pearson FG, editor. Esophageal surgery. New York: Churchill Livingstone, 1995:389-415. [7] Duranceau AC, Forand M, Fauteux JP. Surgery in oculopharyngeal muscular dystrophy. Am J Surg 1980;139:32-39. [8] Duranceau AC, Jamieson GG, Beauchamp G. The technique of cricopharyngeal myotomy. Surg Clin North Am 1983;63:833-839. [9] Taillefer R, Duranceau AC. Manometric and radionuclide assessment of pharyngeal emptying before and after cricopharyngeal myotomy in patients with OPMD. J Thorac Cardiovasc Surg 1988;95:868-875. [10] Meadows JC. Dysphagia in unilateral cerebral lesions. J Neurol Neurosurg Psychiatr 1973;36:853-860. [11] Gordon C, Langton Hewer R, Wade DT. Dysphagia in acute stroke. Br Med J 1987;295:411-414. [12] Lebo CP, U KS, Norris FH. Cricopharyngeal myotomy in amyotrophic lateral sclerosis. Laryngoscope 1976;86:862-868. [13] Loizou LA, Small M, Dalton GA. Cricopharyngeal myotomy in motor neuron disease. J Neurol Neurosurg Psychiatry 1980;43:4245. [14] Montgomery WW, Lynch JP. Oculopharyngeal muscular dystrophy treated by inferior constrictor myotomy. Trans Am Acad Ophthalmol Otolaryngol 1971;75:986-993.