First occurrence of Arnold Chiari type II malformation and associated abnormalities in a Gir calf produced in vitro from Brazil - case report

ABSTRACT This study characterized the clinical, radiological, ultrasound, and necroscopic findings of a case of Arnold-Chiari type II malformation in a Gir breed calf from Brazil. The animal was hospitalized at sixty days of age, in permanent sternal recumbency, cutaneous appendix at the 4th lumbar vertebra and kyphoscoliosis of the caudal and lumbosacral thoracic spine. Radiographic examination of the spine and skull revealed spina bifida and suspected occipital hypoplasia. Upon examination of myelography with an injection of lumbar and atlantooccipital contrast, it was possible to visualize the meningocele at the 4th lumbar vertebra region and findings at the rhombencephalon level of increased regional pressure with failure to fill the contrast in the posterior fossa, in the presence of clear demarcation of the circumvolutions of the cerebral cortex and the subarachnoid space of the cervical spinal cord. Ultrasonographic examination of the cerebellum showed an insinuation of the cerebellar worm through the foramen magnum. The animal did not show changes in complete blood count, biochemical series, and cerebrospinal fluid and was negative for Pestivirus. There was a worsening of the clinical conditions and the animal died. This malformation of unknown etiology must be studied as a differential diagnosis of the nervous system disorders.

Chiari Type I Malformation Presenting with Unilateral Hearing Loss

Introduction Chiari type I malformations can present in different ways, but the most frequent symptom is an occipitocervical headache. Hearing loss as the main presenting symptom is rare. Case A young woman with progressive left-sided unilateral hearing loss was diagnosed with a Chiari type I malformation. She underwent a suboccipital craniectomy with C1 laminectomy and duraplasty. The hearing loss had resolved postoperatively with normalization of the audiometry. Conclusion Chiari type I malformation can present solely with hearing loss. Improvement after surgical decompression is possible. This phenomenon is not emphasized well enough within the neurologic community. In this report, we present a summary of the pathophysiology and management in Chiari type I malformations.