165 - Acute and Chronic Mediastinal Infections

Editors: Shields, Thomas W.; LoCicero, Joseph; Ponn, Ronald B.; Rusch, Valerie W.

Title: General Thoracic Surgery, 6th Edition

Copyright 2005 Lippincott Williams & Wilkins

> Table of Contents > Volume II > The Mediastinum > Section XXX - Mediastinal Cysts > Chapter 196 - Gastroenteric Cysts and Neurenteric Cysts in Infants and Children

Chapter 196

Gastroenteric Cysts and Neurenteric Cysts in Infants and Children

Robert J. Touloukian

Frederick J. Rescorla

Jay L. Grosfeld

Gastroenterogenous and neurenteric cysts are relatively rare mediastinal masses of infancy and childhood. They occur as a result of abnormal separation of embryonic germ cell layers with persistence of endodermal elements closely associated with or within the spinal canal. Heimburger and Battersby (1965), in a 15-year review, reported only three cases in a report concerning 42 mediastinal tumors in children. Various descriptive terminologies have been used to clarify these lesions; however, for the purpose of this discussion, a thoracic neurenteric cyst is defined as a thin-walled cystic structure with an associated cervical or thoracic vertebral anomaly. The association of such cysts with abnormalities of the spinal column is well documented, and, as Alrabeeah and associates (1988) noted, can range along a spectrum from mediastinal masses with minimal spinal abnormality to lesions that are completely within the dura with no extraspinal components.

Gastroenterogenous cysts of the mediastinum are gastric cysts that may or may not communicate with the gastrointestinal tract below the diaphragm. The cyst also may be associated with vertebral anomalies, although it has no intravertebral communication. It would appear that gastroenterogenous and neurenteric lesions arise from a common embryologic defect in development and are part of a spectrum of anomalies that include neurenteric cysts, gastroenteric cysts, and dorsal enteric fistulae and diastematomyelia described by Bremer (1952).

ETIOLOGY

Various theories have been proposed to explain the development of enterogenous cysts. Lewis and Thyng (1907 1908) noted diverticula in the developing alimentary tract in pigs, rabbits, and human embryos and suggested that these normally disappearing diverticula may occasionally persist, leading to enteric cysts. Few researchers have supported this theory.

The vacuolation theory proposed by Keith (1933) relates to the early formation of the gut. As portions of the gut lumen become obliterated, vacuoles form and later coalesce to reform the lumen. If in the process of vacuolation more than one lumen is formed, a mucosal cyst may develop. The presence of smooth muscle in its wall would then allow formation of an enterogenous cyst closely attached or separated from the true lumen. This theory has been supported by Bremer (1944), Ladd and Scott (1944), and Gross and associates (1952). Black and Benjamin (1936) thought that these cysts represented intrathoracic remnants of the omphalomesenteric duct. There have been few supporters of this theory.

Another theory is based on the development of the lung buds. The respiratory tract develops as an outpouching from the primitive foregut. As the lung buds develop, some cells may be sequestered in the mesoderm and develop into cystic structures. The cells within these structures could be either enteric or bronchial epithelium. This theory has been supported by Mixter and Clifford (1929), Olenik and Tandatnick (1946), Bickford (1949), and Wooler (1950).

These theories, however, do not offer any explanation as to the frequent association of spinal anomalies. The existence of spinal abnormalities is essential in the definition of neurenteric cysts and has been reported frequently with mediastinal gastric cysts. In 1935, Stoekel first appreciated this relationship when he described a lesion firmly attached to the vertebrae and noted that the notochord and endoderm were at one time in intimate contact. In 1937, Guillery described a cystic mediastinal lesion associated with a separate cyst in the neural canal. In 1952, Veeneklaas suggested that these abnormalities may develop from an accident involving the spine and foregut at a time when their cells were adjacent to each other. He stated that a failure of complete separation could account for the development of cysts and diverticula of the foregut, including the stomach.

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Two theories that developed from these observations and that relate to the spinal abnormality are based on incomplete separation of the notochord and an ectoderm-endoderm adhesion. In the third week of development, the notochord forms from the ectoderm. These specialized cells then migrate dorsally and are enveloped within the proliferation of mesoderm, which later segments and forms the vertebral bodies. Fallon and associates in 1954 postulated that the withdrawal of the notochord may bring with it a portion of the adjacent endodermal lining, thus leaving a ventral attachment on the notochord to the endoderm (Fig. 196-1). From this lining of endodermal cells, various cysts and duplications could arise, lined with mucosa of the gastrointestinal tract. In addition, closure of the endodermal orifice may result in instances of foregut cysts without any alimentary tract communication. If a communication persisted, it would explain the presence of mediastinal cysts with communication to the gastrointestinal tract in the abdomen. In addition, communication with the notochord would prevent normal anterior formation of the vertebral column. Newnham and colleagues (1984) and others have noted that the degree of abnormality varies from case to case. Some vertebral bodies appear nearly normal, and defects can only be detected by computed tomography. Today, the availability of computed tomography (CT) and magnetic resonance (MR) imaging may allow the identification of a greater number of lesions.

In 1954, McLetchie and associates proposed that a cleft occurred in the notochord along with the formation of an endodermal-ectodermal adhesion with subsequent neural or alimentary tract anomalies, or both. These researchers explained how lesions could form within the chest with or without spinal communication and with or without communication with the infradiaphragmatic gastrointestinal tract. Rhaney and Barclay (1959) postulated that the endoderm becomes intercalated not merely in the notochord, but further dorsally in the neuro-ectoderm to fully explain the unusual presence of an enterogenous cyst within the spinal cord. They suggested that this misplaced endoderm traversed a cleft in the notochord and that some of these cells became detached from the endodermal tube as the foregut moved away from the notochord. The common factor proposed in these theories is that an adhesion between ectoderm and endoderm forms, leading to all of the possible cysts with or without communication to the spinal canal or gastrointestinal tract. Salyer and colleagues (1977) reported that these concepts are currently the most widely accepted theories to account for the occurrence of neurenteric cysts and associated spinal defects.

Fig. 196-1. Diagrammatic illustration of a midline section through an early embryo shows the neuroenteric canal extending forward beneath the neural plate dorsally and the endoderm ventrally. The close contact of the neuroenteric canal and the endoderm of the developing yolk sac may give rise to the formation of the neuroenteric cysts if separation of the two germ cell layers is not complete. From Harrison RG: Development of the vertebral column. In Owen R, et al (eds): Scientific Foundation of Orthopaedics and Traumatology. London: William Heinemann, 1980, p. 163. With permission.

Another theory proposed by Bremer (1952) is that the neurenteric cyst represents an incomplete obliteration of the accessory neurenteric canal of Kovalevsky. This canal is a transient communication between the amniotic cavity and yolk sac on the dorsal surface of the fetus. Persistence of this structure results in a connection between the foregut and dorsal surface of the fetus and theoretically might explain the occurrence of such lesions as neurenteric cysts, dorsal enteric fistula, or diastematomyelia.

NEURENTERIC CYSTS

Clinical Presentation

The age at presentation ranges from the newborn period to adulthood; however, most cases of neurenteric cysts present within the first year of life. Nine of 15 cases reported by Superina and associates (1984) were in patients under 1 year of age. Fernandez (1991) and Rizalar and their associates (1995) reported cases of large mediastinal neurenteric cysts demonstrated by prenatal ultrasonography. In the future, most cases are likely to be recognized by prenatal evaluation. Referral of the mother to a pediatric surgical center is appropriate to enable prompt postnatal management.

The presenting symptoms are determined by the size and location of the cyst and by the effect of expansion on the mediastinal or spinal structures. Occasionally, lesions are asymptomatic and are incidentally observed on chest radiography. Ahmed and co-workers (1972) reported that respiratory symptoms, presence of a mediastinal mass, and a vertebral anomaly form a triad present in 70% of patients. As noted by Alrabeeah and associates (1988), the signs and symptoms of neurenteric cysts are related most frequently to the compressive effect of the mass on the airway. Dyspnea, cough, stridor, and respiratory distress are observed frequently. Many infants become symptomatic shortly after birth as the lesion fills with fluid, expands, and compresses

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vital surrounding structures. The cysts also may be symptomatic if they contain ectopic gastric mucosa. Kropp and colleagues (1987) emphasized that if the cyst has a communication with the gastrointestinal tract below the diaphragm, acid secretion may lead to ulceration and gastrointestinal bleeding.

Fig. 196-2. A, B. Anteroposterior and lateral radiographs show a large neurenteric cyst in the right paravertebral sulcus extending into the right hemithorax. Hemivertebrae are seen at D3 and D7 with accompanying scoliosis. From Beardmore HE, Wigglesworth FW: Vertebral anomalies and alimentary duplications. Pediatr Clin North Am 5:457, 1958. With permission.

Most cases of neurenteric lesions reported in the literature have been identified in the mediastinum with a spinal anomaly or extension into the spinal canal without medullary involvement. The associated spinal abnormalities are usually located in the lower cervical and upper thoracic regions. Fallon and associates (1954), Rhaney and Barclay (1959), and Beardmore and Wigglesworth (1958), among others (see Reading References), noted that these anomalies can include hemivertebrae, fused vertebrae, anterior spina bifida, or an intraspinal mass (Figs. 196-2 and 196-3). Most neurenteric cysts have only a fibrous attachment to the vertebral column. However, several cases have been reported in which the lesion had minimal mediastinal involvement and presented as a neurologic problem only (see Reading References). Menezes and Ryken (1995) noted cysts in the ventral aspect of the cervical spinal canal. In addition, Elwood (1959) reported a case of a mediastinal neurenteric cyst with a cystic swelling in the spinal column with no communication across the vertebrae. Neurologic symptoms, although less common as a presenting symptom, can include back pain, sensory or motor deficits, and gait disturbance. Symptoms of meningeal irritation may occur also. In a case reported by Piramoon and Abbiassioun (1974), a 2-year-old boy developed progressive weakness of his lower limbs, resulting in severe spastic paraplegia. A complete block was noted at the T6 level on myelography; at exploration, a gastric mucosa-lined cyst in the paravertebral sulcus was noted with intravertebral extension.

Fig. 196-3. A, B. Anteroposterior and lateral radiographs of a large mediastinal mass associated with an anomaly of the upper dorsal and cervical spine. From Beardmore HE, Wigglesworth FW: Vertebral anomalies and alimentary duplications. Pediatr Clin North Am 5:457, 1958. With permission.

Pathology

The intraspinal component of a neurenteric cyst has been described by D'Almeida and Stewart (1981) as a thin-walled structure with a single layer of columnar epithelium supported by a thin sheath of connective tissue. In a review of the literature by Lerma and colleagues (1985), the majority of cysts contained a single layer of nonciliated mucin-producing columnar or cuboidal epithelium with an occasional cyst lined with pseudostratified or squamous cells. Rhaney and Barclay (1959) and Kantrowitz and co-workers (1986) described intraspinal cysts consisting of a replica of the stomach wall. Several lesions also have been described by Rhaney and Barclay (1959) with typical small bowel mucosa. The presence of keratin markers and mucus-secreting cuboidal or columnar epithelium confirmed the ectodermal and endodermal origin in three cases of intraspinal neurenteric cysts reported by Kumar and associates (2001).

The portions of the cyst outside of the spinal column frequently are thicker, contain outer smooth muscle layers,

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and contain ectopic gastric mucosa. In addition, the intrathoracic component may communicate through the diaphragm with the proximal gastrointestinal tract.

Fig. 196-4. Chest radiograph demonstrates a right-sided neurenteric cyst in an infant boy.

Diagnosis

The diagnosis of neurenteric cysts is most frequently confirmed with standard radiographs of the chest demonstrating a mass within the paravertebral sulci or visceral compartment (Fig. 196-4). Esophagrams may show displacement from the mass. As pointed out by Superina and associates (1984), a spinal component may accompany at least 20% of mediastinal lesions. Although the respiratory problems are generally noted initially, a careful search must be made for vertebral anomalies. Veeneklaas (1952) reported that the frequency of spinal abnormalities may be underreported in the literature because of reliance only on standard chest radiography. A number of lesions may be identified on tomography that are not detected on standard radiography of the spine, so tomography is an appropriate study to perform when vertebral anomalies and respiratory symptoms coexist. MR imaging has been advocated by Kantrowitz and colleagues (1986) as a means to identify all of the components of a neurenteric cyst with its relationship to the spinal cord and abnormal vertebrae. In addition, Geremia and associates (1988) reported that MR imaging also has been a useful diagnostic tool in cases of completely intraspinal (i.e., intradural, extramedullary) cysts in which the MR pattern can be more indicative of the cystic nature of the lesion than myelography or computed tomographic myelography. In a report by Pierot and colleagues (1988), MR with gadolinium-diethylenetriaminepentaacetic acid enhanced imaging was useful in identifying the cystic nature of these lesions and in delineating medullary compression. In the current era, MR imaging is the diagnostic procedure of choice to delineate the spinal abnormality, and has been recommended for use in the newborn by Gilchrist (1990). MR imaging has also been useful as a postoperative study in diagnosing an anterior meningocele and tethering of the spinal column in a patient of Fernandez and colleagues (1991) with a large neurenteric cyst adherent to the first thoracic vertebra.

Because ectopic gastric mucosa is present in many of these lesions, a technetium 99m pertechnetate scan can be used to preoperatively identify the lesion as an enteric cyst (Fig. 196-5). As noted by Kropp and associates (1987), however, this has rarely been reported in the literature because the diagnosis is frequently not suspected preoperatively.

Fig. 196-5. A. Chest radiograph of 4 -month-old infant with a right-sided thoracic mass (arrow). B. Barium swallow shows distortion of the esophagus by the cyst (arrows). C, D. Technetium 99m pertechnetate scintigraphy shows pathologic accumulation of the radioactive tracer in the mass (arrows) 5 and 40 minutes after injection. From Kropp J, Emons D, Winkler C: Neurenteric cyst diagnosed by technetium 99m pertechnetate sequential scintigraphy. J Nucl Med 28:1218, 1987. With permission.

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Treatment

Although cyst aspiration, marsupialization, and partial resection have been attempted in past years, complete excision of a mediastinal neurenteric cyst is the treatment of choice. Preoperatively, an attempt should be made to determine the extent of the lesion, with particular attention to possible spinal involvement and extension of the cyst below the diaphragm. Primary mediastinal tumors generally can be excised through a standard thoracotomy incision. If the cyst extends below the diaphragm, a thoracoabdominal incision or a thoracotomy and separate abdominal incision may be required to completely excise the cyst. Most lesions with extension into the spinal canal but without neurologic symptoms have been removed through a standard thoracotomy, including the excision of a portion of the cyst extending into the vertebral space. In the case reported by Piramoon and Abbiassioun (1974), a young child with paraplegia had the intraspinal component removed via thoracotomy. A small tear in the dura created during removal was repaired, and the child recovered fully. Most lesions with a significant intraspinal element have been approached with laminectomy and near complete excision of the intradural extramedullary ventral-based cyst. Lerma and colleagues (1985) noted that only 12 of 33 cases were amenable to total resection.

Video-assisted thoracic surgery (VATS) of mediastinal cysts in infants and children has been successfully performed by one of us (FJR) and associates (2000) and Patrick and Rosenberg (2001). This approach is appropriate for resecting neurenteric cysts, when preoperative studies show minimal or no intraspinal extension. Placement of the patient in the prone position rather than the traditional lateral decubitus position has the advantage of allowing gravity to retract the collapsed lung, giving clean access to the posterior area of the mediastinum.

MEDIASTINAL GASTRIC CYSTS

Clinical Presentation

The age at presentation ranges from the newborn period to adults; however, most of these cysts are detected within the first few years of life. Presenting symptoms can develop from compression of surrounding structures, such as the lung, with resulting varying degrees of dyspnea related to the size of the cyst as it expands in the visceral compartment of the mediastinum (Fig. 196-6) or from peptic complications from ectopic gastric tissue. Pokorny and Goldstein (1984) noted that infants generally present with respiratory symptoms, whereas older children present with pain and melena. The most common symptoms include cough, dyspnea, pain, dysphagia, and vomiting. Weight loss and failure to thrive also have been noted in some children. The uninhibited gastric tissue can lead to peptic ulceration

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within the cyst and to bleeding into the gastrointestinal tract if a communication with the cyst is present. The ulcer may perforate into a bronchus, leading to hemoptysis, as noted in four of the cases reviewed by Davis and Salkin (1947), or may perforate into lung parenchyma, as reported by Macpherson and associates (1973), resulting in pulmonary hemorrhage. Severe skin excoriation related to continuous drainage after open drainage of an infected cyst 4 years previously was the presenting symptom in an 8-year-old girl reported by Nicholls (1940 1941). The patient's symptoms resolved after resection of a gastric mucosa-lined cyst.

Fig. 196-6. Three-year-old boy with a foregut cyst presenting with several months of respiratory symptoms, noted on chest radiography (A) with a midlung density, which on the lateral image is a posterior mediastinal mass (B). CT scan (C) demonstrated a cyst with partial occlusion of the bronchus and secondary atelectasis.

Associated Findings

The most frequent associated finding with intrathoracic gastric cysts is a vertebral abnormality. Vertebral defects include hemivertebrae, fused vertebrae, and spina bifida. Gastroenterogenous cysts do not communicate with the vertebral column and are thus different from neurenteric cysts. The two types of cysts most likely have a common etiologic origin, with the main difference being the spinal communication.

Pathology

The cysts generally are located within the visceral mediastinal compartment and expand retropleurally into the lateral hemithorax. The cysts can be isolated within the chest or communicate through the esophageal hiatus or a separate defect in the diaphragm with an intraabdominal structure. Nicholls (1940 1941), Leider (1955), and Fitzgibbons (1980) and their associates reported that the most common

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sites of abdominal communication are the greater curvature of the stomach, lesser curvature of the stomach, duodenum, proximal small bowel, and pancreatic duct.

Fig. 196-7. A. Computed tomographic scan of a 6-year-old girl with a posterior gastroenteric cyst. B. Barium swallow of effacement of the esophagus.

The pathologic examination has demonstrated a cyst lined with typical gastric mucosa. Although this is not specified in all of the reports, most cysts have a typical gastric wall with muscularis mucosa, submucosa, and muscularis layer consisting of two, and occasionally three, layers of smooth muscles. Usually no serosa exists, although Mixter and Clifford (1929) reported one case to have serosa.

Diagnosis

The presence of a gastroenterogenous cyst is usually suspected on standard chest radiography. Newnham and co-workers (1984) reported one child with a gastroenteric cyst detected by prenatal ultrasonography. The radiographic findings can include a rounded posterior density with displacement of the heart and trachea. McLetchie and associates (1954) and Nicholls (1940 1941) noted that they are seen more commonly on the right side. Davis and Salkin (1947) reported bronchograms to have demonstrated displacement, obstruction, bronchiectasis, and, rarely, a bronchocystic fistula. A barium swallow study of the esophagus may demonstrate its displacement from the cyst, although no intraluminal communication has been noted (Fig. 196-7). The upper gastrointestinal barium study, however, may demonstrate retrograde filling of the mediastinal cyst caused by a persistent communication with the infradiaphragmatic gastrointestinal tract (Fig. 196-8). Other diagnostic modalities should include computed tomography and, at times, MR imaging. In addition, one would expect that technetium 99m pertechnetate would be picked up by ectopic gastric mucosa

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within the thoracic cavity in this situation, as has been reported in cases of neurenteric cysts.

Fig. 196-8. Upper gastrointestinal series demonstrates a thoracic gastroenterogenous cyst (arrows) with retrograde filling caused by persistent communication with the infradiaphragmatic gastrointestinal tract. Note associated defects in the vertebral column.

Treatment

Treatment has included initial aspiration in cases of uncertain diagnosis. The aspirated fluid has been described as clear or milky fluid, although Gross and colleagues (1952) reported the presence of hemorrhagic fluid within these cysts, as has Mixter and Clifford (1929) and Veeneklaas (1952). External drainage has been unsuccessful because prolonged drainage has occurred from continued gastric secretion. Marsupialization has been performed in many instances in the past with the use of curettage, insertion of caustic fluids, or gauze packing to destroy the mucosa. These techniques required repeated attempts to destroy the mucosa and may lead to considerable chest wall deformity. These procedures are currently of historic interest only. In a review of 16 duplications within the thoracic cavity, Gross and co-workers (1952) advocated complete excision of the cyst by thoracotomy. VATS is an appropriate alternative in selected cases. In cases in which the lesion arises below the diaphragm, it is essential to remove the infradiaphragmatic portion. In addition, Roberts and Weeks (1957) described a child who developed melena 17 weeks after excision of a mediastinal gastric cyst and was found to have a gastric-lined duplication at the duodenojejunal flexure. Pulmonary resection is generally not required unless the cyst has eroded into the lung parenchyma or a bronchus. In one patient, a right pneumonectomy for a gastric cyst that eroded into the bronchus intermedius was performed. This should be avoided when possible. If the site of location precludes complete excision, Scherer and one of us (JLG) (1986) recommended that the gastric mucosa be stripped from the muscular wall to excise the acid-secreting tissue.

Prognosis

With early diagnosis and complete resection, survival has been excellent. In Gross and associates' series (1952), the only death occurred in a patient who had experienced multiple marsupialization procedures. Roberts and Weeks (1957) reported a death in an 18-week-old child who died preoperatively of pneumonia. Another child reported by Mixter and Clifford (1929) had a persistent mediastinal gastric cyst detected on autopsy after initial treatment with cyst puncture. The child died of pneumonia 14 months later. Morbidity generally has been limited to scoliosis and chest wall deformities in cases managed with marsupialization. In the modern era, with advanced diagnostic technology and perioperative care, complete resection is usually possible and, when successful, is associated with minimal morbidity and mortality.

REFERENCES

Ahmed S, Jolleys A, Dark JF: Thoracic enteric cysts and diverticulae. Br J Surg 59:963, 1972.

Alrabeeah A, et al: Neurenteric cysts a spectrum. J Pediatr Surg. 23:752, 1988.

Beardmore HE, Wigglesworth FW: Vertebral anomalies and alimentary duplication. Pediatr Clin North Am 5:457, 1958.

Bickford J: Mediastinal cysts of gastric origin. Br J Surg 36:410, 1949.

Black RA, Benjamin EL: Enterogenous abnormalities: cyst and diverticula. Am J Dis Child 51:1126, 1936.

Bremer JL: Diverticula and duplications of the intestinal tract. Arch Pathol 38:132, 1944.

Bremer JL: Dorsal intestinal fistula: accessory neurenteric canal; diastematomyelia. AMA Arch Pathol 54:132, 1952.

D'Almeida AC, Stewart DH Jr: Neurenteric cyst: case report and literature review. Neurosurgery 8:596, 1981.

Davis EW, Salkin D: Intrathoracic gastric cysts. JAMA 135:218, 1947.

Elwood JS: Mediastinal duplication of the gut. Arch Dis Child 34:474, 1959.

Fallon M, Gordon ARG, Lendrum AC: Mediastinal cysts of foregut origin associated with vertebral abnormalities. Br J Surg 41:520, 1954.

Fernandez ET, et al: Neurenteric cyst: surgery and diagnostic imaging. J Pediatr Surg 26:108, 1991.

Fitzgibbons RJ Jr, et al: Unusual thoracoabdominal duplication associated with pancreaticopleural fistula. Gastroenterology 79:344, 1980.

Geremia GK, Russell EJ, Clasen RA: MR imaging characteristics of a neurenteric cyst. Am J Neuroradiol 9:978, 1988.

Gilchrist BF, Harrison MW, Campbell JR: Neurenteric cyst: current management. J Pediatr Surg 25:1231, 1990.

Gross RE, Holcomb GW Jr, Farber S: Duplications of the alimentary tract. Pediatrics 9:449, 1952.

Guillery H: Eine in die Wirbels ule eingewachsene mediastinal Zyste (Vorderdarmzyote). Zbl Allg Path Pathol Anat 69:49, 1937.

Harrison RG: Development of the vertebral column. In Owen R, et al (eds): Scientific Foundation of Orthopaedics and Traumatology. London: William Heinemann, 1980, p. 163.

Heimburger IL, Battersby JS: Primary mediastinal tumors of childhood. J Thorac Cardiovasc Surg 50:92, 1965.

Kantrowitz LR, et al: Intraspinal neurenteric cyst containing gastric mucosa: CT and MRI findings. Pediatr Radiol 16:324, 1986.

Keith A: Human Embryology and Morphology. Baltimore: William Wood, 1933.

Kropp J, Emons D, Winkler C: Neurenteric cyst diagnosed by technetium-99m pertechnetate sequential scintigraphy. J Nucl Med 28:1218, 1987.

Kumar R, et al: Intraspinal neurenteric cysts report of three pediatric cases. Child's Nerv Syst 17:584, 2001.

Ladd WE, Scott HW Jr: Esophageal duplications or mediastinal cysts of enteric origin. Surgery 16:815, 1944.

Leider HJ, Snodgrass JJ, Mishrick AS: Intrathoracic alimentary duplications communicating with small intestine. Arch Surg 71:230, 1955.

Lerma S, et al: Intradural neurenteric cyst: review and discussion. Neurochirurgia (Stuttg) 28:228, 1985.

Lewis FT, Thyng FW: The regular occurrence of intestinal diverticula in embryos of the pig, rabbit and man. Am J Anat 7:505, 1907 1908.

Macpherson RI, Reed MH, Ferguson CC: Intrathoracic gastrogenic cysts: a cause of lethal pulmonary hemorrhage in infants. J Can Assoc Radiol 24:362, 1973.

McLetchie NG, Purvis JK, Saunders RL: The genesis of gastric and certain intestinal diverticula and enterogenous cysts. Surg Gynecol Obstet 99: 135, 1954.

Menezes A, Ryken T: Craniocervical intradural neurenteric cysts. Pediatr Neurosurg 22:88, 1995.

Mixter CG, Clifford SH: Congenital mediastinal cysts of gastrogenic and bronchogenic origin. Ann Surg 90:714, 1929.

Newnham JP, et al: Sonographic diagnosis of thoracic gastroenteric cyst in utero. Prenat Diagn 4:467, 1984.

Nicholls MF: Intrathoracic cyst of intestinal structure. Br J Surg 28:137, 1940 1941.

Olenik JL, Tandatnick JW: Congenital mediastinal cysts of foregut origin. Am J Dis Child 71:466, 1946.

Patrick DA, Rosenberg SS: Thoracoscopic resection of mediastinal masses in Infants and children: an evaluation of technique and results. J Pediatr Surg 36:1165, 2001.

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Pierot L, et al: Gadolinium-DTPA enhanced MR imaging of intradural neurenteric cysts. J Comput Assist Tomogr 12:762, 1988.

Piramoon AM, Abbiassioun K: Mediastinal enterogenic cyst with spinal cord compression. J Pediatr Surg 9:543, 1974.

Pokorny WJ, Goldstein IR: Enteric thoracoabdominal duplications in children. J Thorac Cardiovasc Surg 87:821, 1984.

Rescorla FJ, et al: Efficacy of primary and secondary video-assisted thoracic surgery in children. J Pediatr Surg 351:134, 2000.

Rhaney K, Barclay GPT: Enterogenous cysts and congenital diverticula of the alimentary canal with abnormalities of the vertebral column and spinal cord. J Pathol 77:457, 1959.

Rizalar R, et al: A case of mediastinal neurenteric cyst demonstrated by prenatal ultrasound. Eur J Pediatr Surg 5:177, 1995.

Roberts KD, Weeks MM: Two cases of spinal abnormality associated with duplication of the gut and melaena. Br J Surg 44:377, 1957.

Salyer DC, Salyer WR, Eggleston JC: Benign developmental cysts of the mediastinum. Arch Pathol Lab Med 101:136, 1977.

Scherer LR, Grosfeld JL: Congenital esophageal stenosis, esophageal duplication, neurenteric cyst and esophageal diverticulum. In Ashkraft KW, Holder TM (eds): Pediatric Esophageal Surgery. Orlando, FL: Grune & Stratton, 1986, pp. 53 71.

Stoekel KN: Uber einen Fall von intrathorakaler Entodermcyste im Mediastinum posterius bei einem Neugeborenen. Zentralbl Gynakol 59:2178, 1935.

Superina RA, Ein SH, Humphreys RP: Cystic duplications of the esophagus and neurenteric cysts. J Pediatr Surg 19:527, 1984.

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READING REFERENCES

Fabinyi GCA, Adams JE: High cervical spinal cord compression by an enterogenous cyst. J Neurosurg 51:556, 1979.

Klump TE: Neurenteric cyst in the cervical spinal canal of a 10-week-old boy. J Neurosurg 35:472, 1971.

Kwok DMF, Jeffreys RV: Intramedullary enterogenous cyst of the spinal cord. J Neurosurg 56:270, 1982.

Prasad V, Reddy D, Murty J: Cervico-thoracic neurenteric cyst: clinicoradiological correlation with embryogenesis. Child Nerv Syst 12:48, 1996.

Rodacki MA, et al: Intradural, extramedullary high cervical neurenteric cyst. Neuroradiology 29:588, 1987.

Sarihan H, et al: Neurenteric cyst. A case report. J Cardiovasc Surg (Torino) 36:353, 1995.