Syringohydromyelia in association with syringobulbia and syringocephaly: case report

Syringobulbia in Patients with Chiari Malformation Type I: A Systematic Review

This study aimed to summarize the clinical features, diagnosis, and treatment of Chiari malformation type I- (CM-1-) associated syringobulbia. We performed a literature review of CM-1-associated syringobulbia in PubMed, Ovid MEDLINE, and Web of Science databases. Our concerns were the clinical features, radiologic presentations, treatment therapies, and prognoses of CM-1-associated syringobulbia. This review identified 23 articles with 53 cases. Symptoms included headache, neck pain, cranial nerve palsy, limb weakness/dysesthesia, Horner syndrome, ataxia, and respiratory disorders. The most frequently involved area was the medulla. Most of the patients also had syringomyelia. Surgical procedures performed included posterior fossa decompression, foramen magnum decompression, cervical laminectomy, duraplasty, and syringobulbic cavity shunt. Most patients experienced symptom alleviation or resolution postoperatively. A syringobulbic cavity shunt provided good results in refractory cases. Physicians should be aware of the possibility of syringobulbia in CM-1 patients, especially those with symptoms of sudden-onset brain-stem involvement. The diagnosis relies on the disorder's specific symptomatology and magnetic resonance imaging. Our review suggests that the initial therapy should be posterior fossa decomposition with or without duraplasty. In refractory cases, additional syringobulbic cavity shunt is the preferred option.

Signs consistent with syringobulbia may be detected in dogs undergoing MRI

Syringobulbia is a pathologic condition characterized by one or more fluid-filled cavities within the brainstem. This retrospective case series describes observations in eight dogs with syringobulbia diagnosed during MRI. All dogs were adult, small-breed dogs with concurrent syringomyelia and neurologic deficits localized to sites rostral to the spinal cord, which cannot be explained by syringomyelia (eg, six dogs had vestibular signs). On MRI, the fluid-filled cavities had signal intensity characteristics like cerebrospinal fluid, were in the medulla oblongata, and were solitary in each dog. Initially, the shape of the cavity was a slit in five dogs and bulbous in two dogs. Magnetic resonance imaging was repeated in five dogs (6-55 months of age). One dog had progression of syringobulbia from slit-like to bulbous, and four dogs had unchanged slit-like syringobulbia. One dog developed slit-like syringobulbia after cranioplasty. A variety of medical and surgical treatments were performed with improvement of some but not all clinical signs. One dog died following surgery due to cardiopulmonary failure and the other seven dogs were alive at least 1 year after the initial diagnosis, which was the least time of follow-up. One surviving dog developed a unilateral hypoglossal nerve deficit 2 months after the initial diagnosis and megaesophagus 14 months later. In conclusion, detecting a fluid-filled cavity in the medulla oblongata consistent with syringobulbia is possible in dogs undergoing MRI. The cavity is likely acquired, slit-like or bulbous, progressive, or static, and might be associated with breed size and neurologic signs localized to the medulla oblongata.

Syringobulbia: A delayed complication following spinal cord injury - case report

CONTEXT

Syringobulbia is a very rare progressive disorder of central nervous system, with several possible underlying conditions. Rarely, it is also encountered as a late complication of syringomyelia.

FINDINGS

In the present manuscript, a case of a paraplegic patient, due to traumatic spinal cord injury (thoracolumbar fracture), presenting after years progressively developing symptoms of the lower cranial nerves and upper extremities, owed to syringomyelia and syringobulbia, the surgical treatment applied and its outcomes are described. We performed a syringo-peritoneal shunting procedure using a T-tube. The patient's symptoms resolved postoperatively and the cavity's size was reduced to a great degree.

CONCLUSION/CLINICAL RELEVANCE

The late appearance of cranial nerve deficits or symptoms-signs of the upper extremities in a patient with traumatic thoracic spinal cord injury should raise suspicion that post-traumatic syringomyelia or syringobulbia has occurred. In such cases, radiologic evaluation and early surgical drainage of the cyst as a means of preventing significant delayed neurologic deficit is advocated.

Syringobulbia in pediatric patients with Chiari malformation type I

OBJECTIVE Syringobulbia (SB) is a rare entity, with few cases associated with Chiari malformation type I (CM-I) in the pediatric population. The authors reviewed all pediatric cases of CM-I-associated SB managed at their institution in order to better understand the presentation, treatment, and surgical outcomes of this condition. METHODS A prospectively maintained institutional database of craniovertebral junction abnormalities was analyzed to identify all cases of CM-I and SB from the MRI era (i.e., after 1984). The authors recorded presenting symptoms, physical examination findings, radiological findings, surgical treatment strategy, intraoperative findings, and outcomes. SB cases associated with tumors, infections, or type II Chiari malformations were excluded. RESULTS The authors identified 326 pediatric patients with CM-I who were surgically treated. SB was identified in 13 (4%) of these 326 patients. Headache and neck pain were noted in all 13 cases. Cranial nerve abnormalities were common: vagus and glossopharyngeal nerve dysfunction was the most frequent observation. Other cranial nerves affected included the trigeminal, abducens, and hypoglossal nerves. Several patients exhibited multiple cranial nerve palsies at presentation. Central sleep apnea was present in 6 patients. Syringomyelia (SM) was present in all 13 patients. SB involved the medulla in all cases, and extended rostrally into the pons and midbrain in 2 patients; in 1 of these 2 cases the cavity extended further rostrally to the cerebrum (syringocephaly). SB communicated with the fourth ventricle in 7 of the 13 cases. All 13 patients were treated with posterior fossa decompression with intradural exploration to ensure CSF egress out of the fourth ventricle and through the foramen magnum. The foramen of Magendie was found to be occluded by an arachnoid veil in 9 cases. Follow-up evaluation revealed that SB improved before SM. Cranial nerve palsies regressed in 11 of the 13 patients, and SB improved in all 13. CONCLUSIONS The incidence of SB in our surgical series of pediatric patients with CM-I was 4%, and all of these patients had accompanying SM. The SB cavity involved the medulla in all cases and was found to communicate with the fourth ventricle in 54% of cases. Posterior fossa decompression with intradural exploration and duraplasty is an effective treatment for these patients.

Chiari 1 deformity in children: etiopathogenesis and radiologic diagnosis

The metamerically associated normal hindbrain and normal posterior fossa are programmed to grow together in such a way that the tonsils are located above the foramen magnum and surrounded by the cerebrospinal fluid (CSF) of the cisterna magna. This allows the pulsating CSF to move freely up and down across the craniovertebral junction (CVJ). A developmental mismatch between the rates of growth of the neural tissue and of the bony posterior fossa may result in the cerebellar tonsils being dislocated across the foramen magnum. The cause of this may be, rarely, an overgrowth of the cerebellum. More commonly, it is due to an insufficient development of the posterior fossa, possibly associated with a malformation of the craniocervical joint. When it is not due to a remediable cause, such a herniation is called a Chiari 1 deformity. This definition is anatomic (descent of the tonsils below the plane of the foramen magnum) and not clinical: many patients with the deformity are and will remain asymptomatic. Most authors consider that a descent of 5 mm or more is clinically significant but other factors, such as the diameter of the foramen magnum and the degree of tapering of the upper cervical "funnel," are likely to be as important. Morphologic markers of severity on magnetic resonance imaging are, beside the degree of descent, the peg-like deformity of the tonsils, the obstruction of the surrounding CSF spaces (at the craniocervical junction and in the whole posterior fossa), a compression of the cord, an abnormal signal of the cord, and a syringomyelia, typically cervicothoracic. The syringomyelia is assumed to be explained by the "Venturi effect" that is associated with the increased velocity of the CSF across the restricted CSF spaces. Radiologically, the etiopathogenic assessment should address the size and morphology of the posterior fossa, and the functional status of the craniocervical flexion joint. The posterior fossa is best evaluated on sagittal cuts by the posterior fossa pentagon proportionality associated with the line of Chamberlain, and on coronal cuts, by showing a possible shallowness of the posterior fossa. The functional status of the craniocervical joint is altered in case of a proatlantal hypoplasia, as this condition results in a cranial shift of the joint that brings the tip of the dens and of the flexion axis in front of the medulla, that is, in a situation of osteoneural conflict. Less commonly, similar conflicts may also occur when an abnormal craniocervical segmentation results in an instability of the joint.