Romanian Neurosurgery (Jun 2023)
Chiari 1 malformation with Platybasia
Abstract
Background. The incidence of CM-I is estimated to be 1/1,000 births. In rare cases, CM-I is complicated by associations with other malformations of the craniocervical junction, including mainly Basilar invagination (BI). Chiari malformation (CM) is characterized by a congenital malformation of the posterior cranial fossa with cerebellar tonsils herniation through the foramen magnum, probably due to the underdevelopment of the posterior bony skeleton (exo-occipital and supraoccipital bones). CM may be complicated by a variety of other malformations, including platybasia, basilar invagination and occipitalization, although syringomyelia (SM) is the most commonly observed Case Report. A girl, 14 years old came with a chief complaint of headache, which is exacerbated whenever the patient coughed or sneezed. The patient also complained about neck pain and a tingling sensation in her hand. A history of vomiting or seizure has not been found. A history of muscle weakness was not found. On physical examination, the patient has a GCS score of 15 on admission, with normal muscle tone and normal reflexes. The patient has a sensory deficit, on the level below C4. The patient underwent CT Scan and MRI whole spine, Chiari 1 malformation and platybasia were diagnosed. The patient underwent posterior fossa decompression, and postoperatively symptoms of Chiari and sensory deficit gradually improved. Discussion. As an association with this syndrome, there is also basilar invagination as shown by flat basioccipt (platybasia) and upward odontoid projection. hydrocephalus [3]. Virchow coined the term ‘platybasia’ to describe an abnormal flattening of the skull base, a defect which he attributed to abnormal bone development. In addition to the flattening of the base of the skull, there was upward displacement (impression) of the basilar and condylar portions of the occipital bone, which caused infolding, or impression of the foramen magnum, reduction of the posterior fossa, and consequent protrusion of the upper cervical spine into the anterior brainstem, with neurological signs. The symptomatology presented by CM-1 patients is diverse, and its severity does not correlate with the degree of TH, with some asymptomatic cases presenting with prominent TH. The onset of symptoms generally develops gradually, however, trauma, coughing/sneezing or pregnancy can also precipitate the event. The most common treatment for these patients is surgical PCF decompression (alone or with duraplasty), although cerebellar tonsillectomy, cervical laminectomy, and suboccipital cranioplasty are also applied. The goal of these surgical procedures is to decompress the foramen magnum and increase the subarachnoid space in order to avoid the impaction of the cerebellar tonsils, reestablish the CSF flow and reverse the symptoms Conclusion. This patient was diagnosed with Chiari 1 malformation and platybasia, as suggested in the literature, posterior fossa decompression was done and the patient improved clinically
