Cricopharyngeal achalasia is a common cause of dysphagia in patients with mtDNA deletions

Complex neurological and multisystem presentations in mitochondrial disease

Mitochondrial diseases typically involve organs highly dependent on aerobic metabolism and are often progressive with high morbidity and mortality. In the previous chapters of this book, classical mitochondrial phenotypes and syndromes are extensively described. However, these well-known clinical pictures are more the exception rather than the rule in mitochondrial medicine. In fact, more complex, unspecified, incomplete, and/or overlap clinical entities may be even more frequent, with multisystem appearance or progression. In this chapter, we describe some complex neurological presentations, as well as the multisystem manifestations of mitochondrial diseases, ranging from the brain to the other organs.

Detecting myositis as a cause of unexplained dysphagia: Proposal for a diagnostic algorithm

BACKGROUND AND PURPOSE

Idiopathic inflammatory myopathy (IIM) can present with dysphagia as a leading or only symptom. In such cases, diagnostic evaluation may be difficult, especially if serological and electromyographical findings are unsuspicious. In this observational study we propose and evaluate a diagnostic algorithm to identify IIM as a cause of unexplained dysphagia.

METHODS

Over a period of 4 years, patients with unexplained dysphagia were offered diagnostic evaluation according to a specific algorithm: The pattern of dysphagia was characterized by instrumental assessment (swallowing endoscopy, videofluoroscopy, high-resolution manometry). Patients with an IIM-compatible dysphagia pattern were subjected to further IIM-focused diagnostic procedures, including whole-body muscle magnetic resonance imaging, electromyography, creatine kinase blood level, IIM antibody panel and, as a final diagnostic step, muscle biopsy. Muscle biopsies were taken from affected muscles. In cases where no other muscles showed abnormalities, the cricopharyngeal muscle was targeted.

RESULTS

Seventy-two patients presented with IIM-compatible dysphagia as a leading or only symptom. As a result of the specific diagnostic approach, 19 of these patients were diagnosed with IIM according to the European League Against Rheumatism (EULAR) criteria. Eighteen patients received immunomodulatory therapy as a result of the diagnosis. Of 10 patients with follow-up swallowing examination, dysphagia improved in three patients after therapy, while it remained at least stable in six patients.

CONCLUSIONS

Idiopathic inflammatory myopathy constitutes a potentially treatable etiology in patients with unexplained dysphagia. The diagnostic algorithm presented in this study helps to identify patients with an IIM-compatible dysphagia pattern and to assign those patients for further IIM-focused diagnostic and therapeutic procedures.

Cricopharyngeal Achalasia Presenting as Acute Dysphagia in a Pediatric Patient

OBJECTIVE

To describe a case of idiopathic cricopharyngeal achalasia (CPA) in a pediatric patient with acute onset of dysphagia managed conservatively with supportive care.

METHODS

Sixteen-month-old boy presented with acute onset of gagging and coughing with feeding. His exam was notable for a well-appearing child with pooling of oral secretions and coarse breath sounds. Plain film series did not show radio-opaque foreign body (FB) and an esophagram demonstrated an endoluminal filling defect of the cervical esophagus and aspiration of contrast. He was taken to the operating room for urgent endoscopy but no FB or food impaction was observed. He had persistent symptoms that required further evaluation and a multidisciplinary team approach. Bedside laryngoscopy did not reveal any abnormalities. Modified barium swallow (MBS) study revealed upper esophageal sphincter (UES) dysfunction, consistent with cricopharyngeal achalasia. Repeat upper endoscopy with biopsies demonstrated mucosal irritation overlying the UES but histologic studies were negative for infectious causes.

RESULTS

He was treated with supportive care, including nasogastric feedings for nutrition supplementation as he was unable to tolerate oral feedings without aspiration. Over the course of 3 months after discharge, his symptoms resolved and repeat MBS was normal.

CONCLUSION

CPA is a rare cause of dysphagia in the pediatric population. Conservative management with supportive care is a reasonable approach in cases with acute onset in otherwise healthy children without underlying medical problems.

Affection of the Respiratory Muscles in Combined Complex I and IV Deficiency

Objectives:

Combined complex I+IV deficiency has rarely been reported to manifest with the involvement of the respiratory muscles.

Case Report:

A 45y male was admitted for hypercapnia due to muscular respiratory insufficiency. He required intubation and mechanical ventilation. He had a previous history of ophthalmoparesis since age 6y, ptosis since age 23y, and anterocollis since at least age 40y. Muscle biopsy from the right deltoid muscle at age 41y was indicative of mitochondrial myopathy. Biochemical investigations revealed a combined complex I+IV defect. Respiratory insufficiency was attributed to mitochondrial myopathy affecting not only the extra-ocular and the axial muscles but also the shoulder girdle and respiratory muscles. In addition to myopathy, he had mitochondrial neuropathy, abnormal EEG, and elevated CSF-protein. Possibly, this is why a single cycle of immunoglobulins was somehow beneficial. For muscular respiratory insufficiency he required tracheostomy and was scheduled for long-term intermittent positive pressure ventilation.

Conclusion:

Mitochondrial myopathy due to a combined complex I+IV defect with predominant affection of the extra-ocular muscles may progress to involvement of the limb-girdle, axial and respiratory muscles resulting in muscular respiratory insufficiency. In patients with mitochondrial myopathy, neuropathy and elevated cerebrospinal fluid protein, immunoglobulins may be beneficial even for respiratory functions.

Gastrointestinal manifestations of mitochondrial disorders: a systematic review

Mitochondrial disorders (MIDs) due to respiratory-chain defects or nonrespiratory chain defects are usually multisystem conditions [mitochondrial multiorgan disorder syndrome (MIMODS)] affecting the central nervous system (CNS), peripheral nervous system, eyes, ears, endocrine organs, heart, kidneys, bone marrow, lungs, arteries, and also the intestinal tract. Frequent gastrointestinal (GI) manifestations of MIDs include poor appetite, gastroesophageal sphincter dysfunction, constipation, dysphagia, vomiting, gastroparesis, GI pseudo-obstruction, diarrhea, or pancreatitis and hepatopathy. Rare GI manifestations of MIDs include dry mouth, paradontosis, tracheoesophageal fistula, stenosis of the duodeno-jejunal junction, atresia or imperforate anus, liver cysts, pancreas lipomatosis, pancreatic cysts, congenital stenosis or obstruction of the GI tract, recurrent bowel perforations with intra-abdominal abscesses, postprandial abdominal pain, diverticulosis, or pneumatosis coli. Diagnosing GI involvement in MIDs is not at variance from diagnosing GI disorders due to other causes. Treatment of mitochondrial GI disease includes noninvasive or invasive measures. Therapy is usually symptomatic. Only for myo-neuro-gastro-intestinal encephalopathy is a causal therapy with autologous stem-cell transplantation available. It is concluded that GI manifestations of MIDs are more widespread than so far anticipated and that they must be recognized as early as possible to initiate appropriate diagnostic work-up and avoid any mitochondrion-toxic treatment.

Mitochondrial disease in adults: what's old and what's new?

Ten years ago, there was an emerging view that the molecular basis for adult mitochondrial disorders was largely known and that the clinical phenotypes had been well described. Nothing could have been further from the truth. The establishment of large cohorts of patients has revealed new aspects of the clinical presentation that were not previously appreciated. Over time, this approach is starting to provide an accurate understanding of the natural history of mitochondrial disease in adults. Advances in molecular diagnostics, underpinned by next generation sequencing technology, have identified novel molecular mechanisms. Recently described mitochondrial disease phenotypes have disparate causes, and yet share common mechanistic themes. In particular, disorders of mtDNA maintenance have emerged as a major cause of mitochondrial disease in adults. Progressive mtDNA depletion and the accumulation of mtDNA mutations explain some of the clinical features, but the genetic and cellular processes responsible for the mtDNA abnormalities are not entirely clear in each instance. Unfortunately, apart from a few specific examples, treatments for adult mitochondrial disease have not been forthcoming. However, the establishment of international consortia, and the first multinational randomised controlled trial, have paved the way for major progress in the near future, underpinned by growing interest from the pharmaceutical industry. Adult mitochondrial medicine is, therefore, in its infancy, and the challenge is to harness the new understanding of its molecular and cellular basis to develop treatments of real benefit to patients.

Pharyngeal transit in patients with chronic progressive external ophthalmoplegia

PURPOSE

A common presentation of mitochondrial myopathies is chronic progressive external ophthalmoplegia (CPEO). Dysphagia is a complaint in about 50% of cases.

METHOD

This investigation evaluated pharyngeal transit in patients with CPEO. Videofluoroscopic swallowing evaluation was performed with paste, liquid and solid boluses in 14 patients with CPEO and in 16 normal volunteers.

RESULT

There was no difference between patients and volunteers in the duration of pharyngeal swallowing events with the liquid bolus. Compared to control participants, patients with CPEO had significantly shorter duration of pharyngeal transit for paste and solid boluses, of pharyngeal clearance for paste bolus, and of upper oesophageal sphincter transit for paste and solid boluses. Spontaneous multiple swallows and effortful swallows were performed by patients but not by the volunteers.

CONCLUSION

It was concluded that patients with CPEO have shorter pharyngeal transit duration of paste and solid boluses than normal volunteers, which may be a consequence of a spontaneous smaller bolus volume in each swallow and/or effortful swallows.

Cricopharyngeal achalasia in children: indications for treatment and management options

PURPOSE OF REVIEW

Cricopharyngeal achalasia (CPA) is an infrequently encountered but important diagnosis in pediatric dysphagia. This disorder is characterized by difficulty in feeding, regurgitation of feeds, and recurrent aspiration episodes. In this review, we discuss the current understanding of the pathophysiology of the disease and the recent developments in the diagnosis and therapeutic management of CPA.

RECENT FINDINGS

Because of the rarity of the disease, the literature reporting the treatment of CPA is limited to small case series. Although open surgical treatments including cricopharyngeal myotomy have been reported in the past, recent studies advocate less-invasive endoscopic approaches, including balloon dilation, endoscopic cricopharyngeal myotomy, and botulinum toxin injections.

SUMMARY

When CPA is suspected as a cause of dysphagia in a child, the diagnosis can be confirmed with videofluoroscopic swallow studies that demonstrate narrowing at the region of the cricopharyngeus muscle. Treatment should be initiated for children who are unable to feed orally. Current options for treatment include botulinum toxin injections, endoscopic balloon dilation, and open or endoscopic cricopharyngeal myotomy. All techniques have shown success in the treatment of the disease. Further studies comparing treatment modalities are needed before a clear recommendation can be made.

Kearns-Sayre syndrome: a case series of 35 adults and children

Background

Kearns–Sayre syndrome (KSS) is a rare mitochondrial cytopathy, first described at Mayo Clinic in 1958.

Aims

We aimed to define patient and disease characteristics in a large group of adult and pediatric patients with KSS.

Methods

We retrospectively searched the Mayo Clinic medical index patient database for the records of patients with KSS between 1976 and 2009. The 35 patients identified with KSS were analyzed in terms of demographic characteristics, presenting signs and symptoms, diagnostic features, clinical evolution, and associations between disease features and the development of disability.

Results

The mean (standard [SD]) age at KSS presentation was 17 (10) years, but the mean age at diagnosis was 26 (15) years. Ophthalmologic symptoms developed in all patients, and neurologic and cardiac involvement was common. Only four patients (11%) in the series died, but all deaths were from sudden cardiac events. The development of physical disability was significantly associated with cognitive decline (P=0.004) but not with other clinical features, such as sex or sudden cardiac death.

Conclusion

We report the largest case series to date of patients with KSS from a single institution. In addition to the conduction system abnormalities identified in previous series, our cohort included patients with syncope and sudden cardiac death. This underscores the need to consider formal electrophysiologic studies and prophylactic defibrillators in patients with KSS.

Neurologic disorders due to mitochondrial DNA mutations

The mitochondrial DNA (mtDNA) is a compact genome inherited through the maternal lineage. Mutations in mtDNA lead to many of the earliest identified syndromic mitochondrial diseases and display a diverse range of age of onset, symptoms, and outcomes-from isolated childhood onset vision or hearing loss to a multisystemic neurodegenerative disorder with strokes, neuropathy, ophthalmoparesis, and epilepsy beginning at any age. As a heterogeneous group, mitochondrial diseases represent one of the most common metabolic disorders in children and adults, frequently seen by both pediatric and adult specialists. Although the myriad of diseases can make diagnosis seems daunting, the need for extensive supportive care and treatment (the latter for at least a select few mitochondrial disorders) and a rapid and accurate recognition of these disorders is necessary. Here, we provide a review of the most common mitochondrial disease syndromes due to mtDNA mutations.

A dysphagia study in patients with sporadic inclusion body myositis (s-IBM)

The nature of the swallowing impairment in patients with sporadic inclusion body myositis (s-IBM) has not been well characterized. In this study, we examined ten consecutive s-IBM patients using videofluoroscopy (VF) and computed pharyngoesophageal manometry (CPM). The patients were divided into two groups: patients with complaint and without complaint of dysphagia. VF results indicated pharyngeal muscle propulsion (PP) at the hypopharyngeal and upper esophagus sphincter (UES) in all s-IBM patients. Patients without complaint of dysphagia showed a mild degree of PP, whereas a severe form of PP was observed in patients with complaint of dysphagia. CPM revealed that negative pressure during UES opening was not observed in the s-IBM patients with complaint of dysphagia. Incomplete opening and PP at the UES were observed in all s-IBM patients. These results indicate that the dysphagic processes occur subclinically in s-IBM patients who may not report swallowing impairments.

Esophageal contractions in patients with chronic progressive external ophthalmoplegia

BACKGROUND

Chronic progressive external ophthalmoplegia is a mitochondrial myopathy that causes muscular or multisystem symptoms and has dysphagia as one manifestation.

AIM

To evaluate esophageal contractions in patients with chronic progressive external ophthalmoplegia.

METHODS

We studied 14 patients with chronic progressive external ophthalmoplegia and 16 asymptomatic volunteers. The diagnosis of the disease was established by the clinical picture and by mitochondrial DNA analysis in skeletal muscle. We used the manometric method with a perfusion catheter that recorded the esophageal contractions at 2, 7, 12, 17, and 22 cm from the lower esophageal sphincter (LES). All subjects performed in the supine position 20 swallows of a 5-ml bolus of water at room temperature, ten every 30 s and ten every 10 s.

RESULTS

The amplitude, duration, and area under the curve of contractions at 17 and 22 cm from the LES were lower in patients than in volunteers for swallows performed at 10-s and 30-s intervals (P<0.01). There was no difference in contractions at 7 and 2 cm, except for the contractions at 2 cm after swallows performed at 30-s intervals. The interval between the onset of contractions between 7 and 2 cm and between 22 and 2 cm was lower in patients than in volunteers, with swallows performed every 10 s and every 30 s.

CONCLUSION

There is impairment of esophageal contractions in patients with chronic progressive external ophthalmoplegia, mainly in the proximal esophageal body.

Nature and frequency of respiratory involvement in chronic progressive external ophthalmoplegia

Chronic progressive external ophthalmoplegia (CPEO) is a relatively common mitochondrial disorder. Weakness of the extra-ocular, limb girdle and laryngeal muscles are established clinical features. Respiratory muscle involvement however has never been studied systematically, even though respiratory complications are one of the main causes of death. We therefore determined the prevalence and nature of respiratory muscle involvement in 23 patients with genetically confirmed CPEO. The main finding was decreased respiratory muscle strength, both expiratory (76.8% of predicted, p = 0.002) and inspiratory (79.5% of predicted, p = 0.004). Although the inspiratory vital capacity (92.5% of predicted, p = 0.021) and the forced expiratory volume in 1 s (89.3% of predicted, p = 0.002) were below predicted values, both were still within the normal range in the majority of patients. Expiratory weakness was associated with a decreased vital capacity (ρ = 0.502, p = 0.015) and decreased peak expiratory flow (ρ = 0.422, p = 0.045). Moreover, expiratory muscle strength was lower in patients with limb girdle weakness (62.6 ± 26.1% of predicted vs. 98.9 ± 22.5% in patients with normal limb girdle strength, p = 0.003), but was not associated with other clinical features, subjective respiratory complaints, disease severity or disease duration. Since respiratory involvement in CPEO is associated with severe morbidity and mortality, the present data justify periodic assessment of respiratory functions in all CPEO patients.

Multisystem disorder in late-onset chronic progressive external ophthalmoplegia

INTRODUCTION

Chronic progressive external ophthalmoplegia (CPEO) is a mitochondrial syndrome on a disease spectrum with Kearns-Sayre syndrome (KSS). Clinical presentation is variable and our experience suggested that phenotypic differences exist in CPEO with onset after age 20.

METHODS

This descriptive study is a retrospective chart review of 40 patients with late-onset CPEO. Clinical features, laboratory and neurophysiology results were reviewed.

RESULTS

Multisystem dysfunction was very common in this series. Gastrointestinal dysfunction was more common than expected (60%) as was migraine headache (40%). Clinical characteristics on the KSS disease spectrum were uncommon in this series with only 2.5% having pigmentary retinopathy, 5% with cardiac conduction abnormality, and 22.5% having endocrinopathy (most often thyroid dysfunction rather than diabetes). Neurophysiology abnormalities included length-dependent axonal polyneuropathy in 44% (sometimes subclinical) and myopathic EMG changes in 26%. Exposure to sources of acquired mitochondrial toxicity including cigarette use and hepatitis C infection were more common than expected in this series.

DISCUSSION

Phenotype was different in this late-onset series compared with previous reports in CPEO patients. In this series of late-onset patients, multi-organ dysfunction was more common than previously reported in CPEO, and some classical mitochondrial manifestations, such as pigmentary retinopathy were rare. We suggest that acquired mitochondrial toxicity may have a role in the pathogenesis of adult-onset CPEO.

Approaches to the treatment of mitochondrial diseases

Therapy for mitochondrial diseases is woefully inadequate. However, lack of a cure does not equate with lack of treatment. Palliative therapy is dictated by good medical practice and includes anticonvulsant medication, control of endocrine dysfunction, and surgical procedures. Removal of noxious metabolites is centered on combating lactic acidosis, but extends to other metabolites. Attempts to bypass blocks in the respiratory chain by administration of electron acceptors have not been successful, but this may be amenable to genetic engineering. Administration of metabolites and cofactors is the mainstay of real-life therapy and is especially important in disorders due to primary deficiencies of specific compounds, such as carnitine or coenzyme Q10 (CoQ10). There is increasing interest in the administration of reactive oxygen radicals (ROS) scavengers, both in primary mitochondrial diseases and in neurodegenerative diseases. Gene therapy is a challenge because of polyplasmy and heteroplasmy, but novel experimental approaches are being pursued. One important strategy is to decrease the ratio of mutant to wild-type mitochondrial genomes ("gene shifting") by different means: (1) converting mutated mitochondrial DNA (mtDNA) genes into normal nuclear DNA genes ("allotopic expression"); (2) importing cognate genes from other species ("xenotopic expression"); (3) correcting mtDNA mutations by importing specific restriction endonucleases; (4) selecting for respiratory function; and (5) inducing muscle regeneration. Germline therapy raises ethical problems but is being considered for prevention of maternal transmission of mtDNA mutations. Preventive therapy through genetic counseling and prenatal diagnosis is becoming increasingly important for nuclear DNA-related disorders.

Mitochondrial neurogastrointestinal encephalomyopathy: evidence of mitochondrial DNA depletion in the small intestine

BACKGROUND & AIMS

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disease clinically defined by gastrointestinal dysmotility, cachexia, ptosis, ophthalmoparesis, peripheral neuropathy, white-matter changes in brain magnetic resonance imaging, and mitochondrial abnormalities. Loss-of-function mutations in thymidine phosphorylase gene induce pathologic accumulations of thymidine and deoxyuridine that in turn cause mitochondrial DNA (mtDNA) defects (depletion, multiple deletions, and point mutations). Our study is aimed to define the molecular basis of gastrointestinal dysmotility in a case of MNGIE.

METHODS

By using laser capture microdissection techniques, we correlated histologic features with mtDNA abnormalities in different tissue components of the gastrointestinal wall in a MNGIE patient and ten controls.

RESULTS

The patient's small intestine showed marked atrophy and mitochondrial proliferation of the external layer of muscularis propria. Genetic analysis revealed selective depletion of mtDNA in the small intestine compared with esophagus, stomach, and colon, and microdissection analysis revealed that mtDNA depletion was confined to the external layer of muscularis propria. Multiple deletions were detected in the upper esophagus and skeletal muscle. Site-specific somatic point mutations were detected only at low abundance both in the muscle and nervous tissue of the gastrointestinal tract. Analysis of the gastrointestinal tract from 10 controls revealed a non-homogeneous distribution of mtDNA content; the small intestine had the lowest levels of mtDNA.

CONCLUSION

Atrophy, mitochondrial proliferation, and mtDNA depletion in the external layer of muscularis propria of small intestine indicate that visceral myopathy is responsible for gastrointestinal dysmotility in this MNGIE patient.

Cricopharyngeal achalasia responsive to balloon dilation in an infant

This report describes an infant with vomiting and significant weight loss attributable to cricopharyngeal achalasia, a rare finding in children. The infant responded to balloon dilation of the upper esophageal sphincter, with resolution of symptoms and return to presymptomatic growth parameters. A brief description of the clinical features, diagnostic evaluation, and treatment options for cricopharyngeal achalasia is included.

Mitochondriopathies

Mitochondriopathies (MCPs) are either due to sporadic or inherited mutations in nuclear or mitochondrial DNA located genes (primary MCPs), or due to exogenous factors (secondary MCPs). MCPs usually show a chronic, slowly progressive course and present with multiorgan involvement with varying onset between birth and late adulthood. Although several proteins with signalling, assembling, transport, enzymatic function can be impaired in MCP, most frequently the activity of the respiratory chain (RC) protein complexes is primarily or secondarily affected, leading to impaired oxygen utilization and reduced energy production. MCPs represent a diagnostic challenge because of their wide variation in presentation and course. Systems frequently affected in MCP are the peripheral nervous system (myopathy, polyneuropathy, lactacidosis), brain (leucencephalopathy, calcifications, stroke-like episodes, atrophy with dementia, epilepsy, upper motor neuron signs, ataxia, extrapyramidal manifestations, fatigue), endocrinium (short stature, hyperhidrosis, diabetes, hyperlipidaemia, hypogonadism, amenorrhoea, delayed puberty), heart (impulse generation or conduction defects, cardiomyopathy, left ventricular non-compaction heart failure), eyes (cataract, glaucoma, pigmentary retinopathy, optic atrophy), ears (deafness, tinnitus, peripheral vertigo), guts (dysphagia, vomiting, diarrhoea, hepatopathy, pseudo-obstruction, pancreatitis, pancreas insufficiency), kidney (renal failure, cysts) and bone marrow (sideroblastic anaemia). Apart from well-recognized syndromes, MCP should be considered in any patient with unexplained progressive multisystem disorder. Although there is actually no specific therapy and cure for MCP, many secondary problems require specific treatment. The rapidly increasing understanding of the pathophysiological background of MCPs may further facilitate the diagnostic approach and open perspectives to future, possibly causative therapies.

Cricopharyngeal myotomy in a patient with situs inversus totalis

Otolaryngologists must remain vigilant in understanding the complex anatomy of the head and neck and must always be cognizant of deviations from normal anatomy. This text discusses an interesting case that should remind surgeons of the variable course that the recurrent laryngeal nerve takes on either side of the neck and the special consideration that must be taken in performing surgery near the nerve.

[Laryngopharyngeal structural analysis and its morphofunctional correlation with cricopharyngeal myotomy, botulinum toxin injection and balloon dilation]

BACKGROUND

The cricopharyngeal muscle is of the skeletal type and, in this way, unable to sustain continuous contraction for long periods. Despite of this it has been considered as the responsible by the high pressure area, registered by manometry into the pharyngoesophageal transition. For this reason, it has been the object of therapeutics that promote the rupture of its integrity.

AIMS

To give the anatomical bases to define the limits of participation of the cricopharyngeal muscle in the pharyngoesophageal transition function. To consider a morphological and functional alternative to explain the high pressure area on pharyngoesophageal transition and the implications of the myotomy, use of the botulinum toxin and balloon dilatation on pharyngoesophageal transition function.

MATERIAL AND METHOD

Study of the laryngopharyngeal region in their morphologic characteristics and relationships on 24 pieces obtained from adults' corpses of both sexes fixed in 10% formaldehyde solution.

RESULTS

The cricopharyngeal muscle presenting its anterior-lateral insertion, with a C-shaped outline, on the posterior-lateral edge of the cricoid cartilage. This kind of morphology blocks the possibility to generate a predominant anterior and posterior high pressure during its contraction like that we find at the pharyngoesophageal transition. The observation of this kind of pressure has its explanation in a tweezers-like relationship exerted on one side by the vertebral body and on the other side by the posterior contour of the cricoid cartilage.

CONCLUSIONS

The muscular organization of the laryngopharyngeal segment allowed us to sustain that a large myotomy of the pharyngoesophageal transition, that takes more than just the cricopharyngeal transversal fasciculus, hinders the ejection function in a region where the dimension do not need any parietal sectioning. Myotomy that encompasses only the transversal fasciculus can contribute to improve the pharyngoesophageal flux by a decrease of the local resistance. The efficiency of this myotomy depends mostly on some residual pharyngeal ejection force and also on a slight hyolaryngeal displacement. The transversal fasciculus of the cricopharyngeal muscle is a narrow strip of muscular mass to be injected by percutaneous way with solution of botulinum toxin; maybe endoscopically. For this reason, dose, dilution and injection sites have an important meaning in the cricopharyngeal therapeutics using botulinum toxin. The efficiency of this procedure, like myotomy, depends on some residual pharyngeal ejection force and on, at least, some hyolaryngeal displacement. The dilation of the pharyngoesophageal transition with pneumatic balloon does not seem to be an adequate procedure for a region that does not present a narrow lumen determined by fibrosis. For anatomical characteristics of the TFE region, mean pressure as registered by the manometric method does not evaluate either the effectiveness or inadequacy of surgical myotomy, denervation or dilation using pneumatic balloon.

Chronic progressive external ophthalmoplegia

Chronic progressive external ophthalmoplegia (CPEO) is a descriptive term for a heterogenous group of disorders characterized by chronic, progressive, bilateral, and usually symmetric ocular motility deficit and ptosis. Significant pain, proptosis, or pupil involvement are not features of CPEO and should prompt evaluation for alternative etiologies. Mitochondrial DNA mutations are increasingly being recognized as the etiology for CPEO syndromes. Clinicians should recognize the specific syndromes associated with CPEO, characterized by variable systemic, neurologic, or other findings. Treatment is limited, but newer therapies are being investigated.