Resolution of syringomyelia in ten cases of "up-and-down Chiari malformation" after posterior fossa decompression

Abstract

The authors describe ten cases of syringomyelia without hindbrain herniation depicted by preoperative magnetic resonance imaging (MRI) in supine position. However, the herniation was observed in all cases during the operation with the patient in sitting position. The postoperative MRI revealed an intense reduction of the syrinx in all patients, as well as it was also observed a clinical amelioration in all cases. The surgical treatment was based on a large craniectomy with the patient in sitting position, tonsillectomy, large opening of the fourth ventricle and duraplasty with creation of a large cisterna magna. Key words: Chiari malformation, syringomyelia, craniovertebral decompression.Resolução de siringomielia em dez casos de malformação de Chiari observada apenas com o paciente em posição sentada durante a descompressão da fossa posterior RESUMO Os autores descrevem 10 casos de siringomielia sem herniação do rombencéfalo, observada na ressonância magnética realizada em decúbito dorsal. Por outro lado, a herniação foi observada em todos os pacientes durante a operação com o paciente em posição sentada. A ressonância magnética pós-operatória evidenciou redução da cavidade siringomiélica nos dez pacientes, bem como foi observada melhora clínica em todos os casos. O tratamento cirúrgico consistiu de craniectomia ampla da fossa posterior, tonsilectomia, abertura ampla do quarto ventrículo e duroplastia com a criação de ampla cisterna magna. Palavras-chave: malformação de Chiari, siringomielia, descompressão craniovertebral.

Posterior fossa decompression with tonsillectomy in 104 cases of basilar impression, Chiari malformation and/or syringomyelia

“…In ten consecutive patients with SM, no hindbrain herniation was detected by MRI in the supine position, but the herniation of the cerebellar tonsils was observed in all of them during the surgery in the sitting position 30 . In other five patients without SM there was no tonsillar herniation showed by MRI in the supine position, however, in the sitting position, they migrated caudally in three cases and, finally, in the other two patients, the cerebellar tonsils did not herniate.…”

Long-Term Outcomes After Small-Bone-Window Posterior Fossa Decompression and Duraplasty in Adults with Chiari Malformation Type I

“…Regarding the treatment of CMI, most authors agree that posterior fossa decompression can lead to both clinical and radiological improvement (10,13,23,(27)(28)(29). However, specific surgical procedures remain controversial, such as craniectomy and bone-window size, whether the arachnoid should be opened and whether cerebellar tonsil should be manipulated (13,19,26,27,32).…”

Anesthetic management during Cesarean section in a woman with residual Arnold-Chiari malformation Type I, cervical kyphosis, and syringomyelia

“…[24] Once the surgery is completed, the posterior fossa volume expands and the cerebellar tonsils ascend. [824] The underlying syringomyelia usually resolves over time.…”

“…[24] Once the surgery is completed, the posterior fossa volume expands and the cerebellar tonsils ascend. [824] The underlying syringomyelia usually resolves over time. In some cases, the placement of syringopleural and syringoperitoneal shunts is necessary in order to improve patient symptoms such as headache, numbness, weakness, and coordination difficulties.…”

“…In some cases, the placement of syringopleural and syringoperitoneal shunts is necessary in order to improve patient symptoms such as headache, numbness, weakness, and coordination difficulties. [824]…”