Hypoxic and hypercapneic arousal responses from quiet sleep were tested in seven infants with myelomeningocele and Arnold-Chiari malformation who were symptomatic with apnea and/or hypoventilation. All infants with myelomeningocele required tracheostomy and posterior fossa decompression. Responses were compared with those of nine healthy control infants. To assess hypoxic arousal, inspired PO2 ...

CASE REPORT We present a patient with bilateral Terson's syndrome after brainstem surgical decompression as treatment for her Arnold-Chiari I malformation. We have studied and compared the progression of preretinal hemorrhage after Nd:YAG laser treatment of the right eye and observation of the left, and also the formation of an epiretinal membrane in the left eye. DISCUSSION Treatment of Ters...

OBJECT In 1998 the authors identified 5 patients with syringomyelia and no evidence of Chiari malformation Type I (CM-I). Magnetic resonance imaging of the entire neuraxis ruled out other causes of a syrinx. Ultimately, abnormal CSF flow at the foramen magnum was the suspected cause. The label "Chiari 0" was used to categorize these unique cases with no tonsillar ectopia. All of the patients un...

A 47-year-old woman was admitted for bilateral lower lobe pneumonia with respiratory distress. Two episodes of respiratory failure developed despite improvement of pneumonia after antibiotic chemotherapy. Loss of consciousness and quadriplegia accompanied the last episode of respiratory failure. Arnold-Chiari malformation type 1 was diagnosed and a suboccipital craniectomy was performed. The ne...

INTRODUCTION Chiari type I malformation (CM-I) is characterised by caudal ectopia of the cerebellar tonsils through the foramen magnum. This is associated with brain stem, high spinal cord, and cranial nerve compression phenomena. The most frequent symptoms are occipital headaches and dizziness. Less well-known symptoms are sleep disorders and nocturnal respiratory abnormalities. SOURCES MEDL...

While Chiari I malformation is a relatively common finding on MRI imaging, the vast majority of patients are asymptomatic and those who do present typically follow a slow course of chronic or subacute progression of symptoms. Emergent deterioration of existing Chiari malformation is rare. We present two patients with previously undiagnosed Chiari I malformation presenting with acute deteriorati...

There can be a wide variety of symptoms in these patients, including headache, weakness, numbness of the limbs, unsteadiness and loss of balance.2 A variety of respiratory disorders have been described including acute respiratory failure,2 respiratory arrest I and sleep apnoea.' It is extremely unusual for a patient with the condition to have no abnormal neurological signs on presentation, ifap...

OBJECTIVE We previously reported the resolution of syringohydromyelia without cerebellar tonsillar ectopia in five patients after posterior fossa decompression of the so-called Chiari 0 malformation. A sixth patient is described. In this study, the anatomy of the posterior fossa is analyzed using radiological imaging, enabling features of the posterior fossa in this uncommon subgroup of childre...

The hindbrain herniation syndrome (51), often referred to as the Chiari I malformation, is a disorder that has traditionally been defined as a downward herniation of the cerebellar tonsils through the foramen magnum (8, 9, 36). The extent of tonsillar herniation is recognized as being more than 4 to 5 mm below the plane of foramen magnum on sagittal magnetic resonance images (11, 13, 28, 30, 33...