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Journal of Neurological Surgery. Part... Feb 2021The video demonstrates the steps for an endoscopic transnasal approach for resection of the odontoid causing platybasia with basilar invasion. The video reviews...
The video demonstrates the steps for an endoscopic transnasal approach for resection of the odontoid causing platybasia with basilar invasion. The video reviews the clinical presentation, preoperative workup and imaging, patient positioning, technical nuances of the procedure, reconstruction, and clinical outcomes including postoperative imaging. The surgery was performed by a skull base team including otolaryngologists and neurological surgeons at a large regional tertiary care facility. A 59-year-old female with the Chiari I malformation with history of multiple revision cervical spinal surgeries presents with neck pain. Preoperative imaging showed a hypoplastic clivus and platybasia with basilar invasion. The main outcome measures consist of safely removing the odontoid with appropriate closure, reversal of the patient symptoms, and prevention of both operative complications and ventral compression of the brainstem. The patient's neck pain improved. There were no intraoperative or postoperative complications besides anterior rightward nasal septal deviation causing unilateral nasal obstruction. A septoplasty was performed to correct the septal deviation 6 months after the initial procedure. The endoscopic transnasal approach to the resection of odontoid is a safe and effective treatment to address basilar invasion and ventral compression of the brainstem. The link to the video can be found at: https://youtu.be/m_c3-Vn-l80 .
PubMed: 33717801
DOI: 10.1055/s-0040-1705161 -
Scientific Reports Aug 2023Craniosynostosis is characterized by the premature fusion and ossification of one or more of the sutures of the calvaria, often resulting in abnormal features of the...
Craniosynostosis is characterized by the premature fusion and ossification of one or more of the sutures of the calvaria, often resulting in abnormal features of the face and the skull. In cases in which growth of the brain supersedes available space within the skull, developmental delay or cognitive impairment can occur. A complex interplay of different cell types and multiple signaling pathways are required for correct craniofacial development. In this study, we report on two siblings with craniosynostosis and a homozygous missense pathogenic variant within the IL11RA gene (c.919 T > C; p.W307R). The patients present with craniosynostosis, exophthalmos, delayed tooth eruption, mild platybasia, and a basilar invagination. The p.W307R variant is located within the arginine-tryptophan-zipper within the D3 domain of the IL-11R, a structural element known to be important for the stability of the cytokine receptor. Expression of IL-11R-W307R in cells shows impaired maturation of the IL-11R, no transport to the cell surface and intracellular retention. Accordingly, cells stably expressing IL-11R-W307R do not respond when stimulated with IL-11, arguing for a loss-of-function mutation. In summary, the IL-11R-W307R variant, reported here for the first time to our knowledge, is most likely the causative variant underlying craniosynostosis in these patients.
Topics: Humans; Craniosynostoses; Skull; Head; Brain; Arginine
PubMed: 37596289
DOI: 10.1038/s41598-023-39466-y -
Current Osteoporosis Reports Aug 2016Notch plays an important function in skeletal homeostasis, osteoblastogenesis, and osteoclastogenesis. Hajdu-Cheney syndrome (HCS) is a rare disease associated with... (Review)
Review
Notch plays an important function in skeletal homeostasis, osteoblastogenesis, and osteoclastogenesis. Hajdu-Cheney syndrome (HCS) is a rare disease associated with mutations in NOTCH2 leading to the translation of a truncated NOTCH2 stable protein. As a consequence, a gain-of-NOTCH2 function is manifested. HCS is inherited as an autosomal dominant disease although sporadic cases exist. HCS is characterized by craniofacial developmental defects, including platybasia and wormian bones, osteoporosis with fractures, and acro-osteolysis. Subjects may suffer severe neurological complications, and HCS presents with cardiovascular defects and polycystic kidneys. An experimental mouse model harboring a HCSNotch2 mutation exhibits osteopenia secondary to enhanced bone resorption suggesting this as a possible mechanism for the skeletal disease. If the same mechanisms were operational in humans, anti-resorptive therapy could correct the bone loss, but not necessarily the acro-osteolysis. In conclusion, HCS is a devastating disease associated with a gain-of-NOTCH2 function resulting in diverse clinical manifestations.
Topics: Acro-Osteolysis; Animals; Bone Resorption; Disease Models, Animal; Gain of Function Mutation; Hajdu-Cheney Syndrome; Humans; Mice; Nervous System Diseases; Osteoporosis; Osteoporotic Fractures; Platybasia; Polycystic Kidney Diseases; Receptor, Notch2
PubMed: 27241678
DOI: 10.1007/s11914-016-0311-6 -
Clinics (Sao Paulo, Brazil) 2019Basilar invagination (BI) and Chiari malformation type I (CM-I) are very important anomalies that introduce instability and compression in the occipitocervical... (Review)
Review
Basilar invagination (BI) and Chiari malformation type I (CM-I) are very important anomalies that introduce instability and compression in the occipitocervical transition region and have complex clinical characteristics. These anomalies vary according to the affected structures. The present study revises current knowledge regarding the anatomy, anatomo-physiology, clinical manifestations, and radiological findings of these entities and the associated surgical treatment approaches. A bibliographic survey was performed through a search in the Medline, PubMed, SciELO, Science and LILACS databases. When associated, these craniovertebral malformations result in neurological deficits due to neural parenchyma compression; however, the presence of microtraumas due to repetitive lesions caused by the bulb and cervical marrow instability has been highlighted as a determinant dysfunction. Surgical treatment is controversial and has many technical variations. Surgery is also challenging due to the complex anatomical characteristics and biomechanics of this region. Nevertheless, advances have been achieved in our understanding of related mechanisms, and compression and atlantoaxial instability are considered key elements when selecting the surgical approach.
Topics: Arnold-Chiari Malformation; Decompression, Surgical; Humans; Joint Instability; Magnetic Resonance Imaging; Odontoid Process; Platybasia
PubMed: 30970117
DOI: 10.6061/clinics/2019/e653 -
Medicine Sep 2022Retrospective cross-sectional study To evaluate the validity and obtain optimal cutoff values of 3 radiologic measurements for the diagnosis of basilar invagination...
Retrospective cross-sectional study To evaluate the validity and obtain optimal cutoff values of 3 radiologic measurements for the diagnosis of basilar invagination (BI). Two hundred seventy-six patients (46 patients who underwent atlantoaxial fusion for BI and 230 patients who were treated for minor cervical trauma) seen in a single institution from January 2010 to December 2016 were included in this study. Age, sex, and body mass index were adjusted for the patients. The Ranawat index (RI), modified Ranawat method (MRM), and Redlund-Johnell method (RJM) were used to diagnose BI on plain radiographs. The sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and diagnostic odds ratio of 3 radiologic measurements were compared. We also calculated the optimized cutoff values of 3 radiologic measurements using the receiver operating characteristic curve in our patients. The mean age of the 130 women and 146 men was 58.3 ± 14.5 years. The mean values of RI, MRM, and RJM in the BI group were 12.5 ± 3.3, 23.1 ± 3.8, and 27.3 ± 3.6 in women and 13.6 ± 2.6, 26.8 ± 4.2, and 34.7 ± 5.1 in men. There was a significant difference between the sexes (P < .05). The accuracies of RI, MRM, and RJM were 95%, 89.6%, and 92.3% in women and 93%, 68.2%, and 85.4% in men, respectively. The optimized cutoff values of RI, MRM, and RJM were 14, 26, and 32 mm in women and 15, 29, and 38 mm in men. Three radiologic measurements (RI, MRM, and RJM) are reliable for the diagnosis of BI even in the era of cross-sectional images. The validity of these measurements depends on sex and particular radiologic measurement. The optimized cutoff values of RI, MRM, and RJM were 14, 26, and 32 mm in women and 15, 29, and 37 mm in men. These cutoff values showed high validity when compared to the CT and MRI findings.
Topics: Adult; Aged; Atlanto-Axial Joint; Cross-Sectional Studies; Female; Humans; Male; Middle Aged; Platybasia; Radiography; Retrospective Studies
PubMed: 36197204
DOI: 10.1097/MD.0000000000030552 -
Radiologia Brasileira 2020The present study aims to perform a reproducibility study of the clivus-canal angle (CCA), Welcker's basal angle (WBA), and the distance from the odontoid process to...
OBJECTIVE
The present study aims to perform a reproducibility study of the clivus-canal angle (CCA), Welcker's basal angle (WBA), and the distance from the odontoid process to Chamberlain's line (DOCL) on magnetic resonance imaging (MRI).
MATERIALS AND METHODS
Two medical students and two radiologists respectively evaluated 100 and 50 consecutive MRI scans of adult skulls, selected randomly. Each examiner, working independently and blinded to the previous results, performed readings for each patient on two different occasions. Measurements were performed in T1-weighted sequences acquired in the midsagittal plane. The levels of intraobserver reproducibility and interobserver agreement were evaluated by calculating the intraclass correlation coefficients (ICCs) and the corresponding 95% confidence intervals.
RESULTS
The mean values obtained by the examiners were 150º for the CCA, 130º for the WBA, and 2.5 mm for the DOCL. The ICC for interobserver agreement was 0.980, 0.935, and 0.967, for the CCA, WBA, and DOCL, respectively, for the students, compared with 0.977, 0.941, and 0.982, respectively, for the radiologists, and 0.980, 0.992, and 0.990, respectively, for all of the examiners together. In the analysis of intraobserver agreement, the ICC ranged from 0.929 to 0.959 for the CCA, from 0.918 to 0.964 for the WBA, and from 0.918 to 0.981 for the DOCL.
CONCLUSION
The measurement of the CCA, WBA, and DOCL appears to show excellent intraobserver reproducibility and interobserver agreement on MRI.
PubMed: 33071375
DOI: 10.1590/0100-3984.2019.0068 -
Journal of Clinical Neurology (Seoul,... Mar 2022
PubMed: 35274843
DOI: 10.3988/jcn.2022.18.2.241 -
World Neurosurgery Jul 2023Patients with Chiari malformation (CM) associated with atlantoaxial dislocation (AAD) and basilar invagination (BI) may present with a small posterior cranial fossa, but...
OBJECTIVE
Patients with Chiari malformation (CM) associated with atlantoaxial dislocation (AAD) and basilar invagination (BI) may present with a small posterior cranial fossa, but data on the volumetric analysis are lacking. Additionally, whether additional foramen magnum decompression (FMD) is needed together with atlantoaxial fusion remains controversial. This study evaluated the volumetric alterations of the posterior cranial fossa in these patients and analyzed the radiological and clinical outcomes after posterior C1-C2 reduction and fixation plus C1 posterior arch resection.
METHODS
Thirty-two adult CM patients with AAD and BI (CM-AAD/BI group) and 21 AAD and BI patients without CM (AAD/BI-only group) who received posterior atlantoaxial fusion plus C1 posterior arch resection were retrospectively studied. The clinical and radiological outcomes and volumetric measurements of the posterior cranial fossa were evaluated.
RESULTS
The majority of CM-AAD/BI patients (94%) improved clinically and radiologically at 12 mo postoperatively, and none required additional FMD. Morphological analysis revealed a significant reduction in the bony posterior cranial fossa volumes of the CM-AAD/BI group (P < 0.01) and the AAD/BI-only group (P < 0.01) relative to those of the CM group. No significant differences were observed between the CM-AAD/BI and AAD/BI groups.
CONCLUSIONS
Compared with patients with simple CM, patients with AAD/BI with or without CM demonstrated a considerably and equally reduced bony posterior cranial fossa volume. No additional FMD is needed in the treatment of CM-AAD/BI patients after posterior reduction and fusion plus C1 posterior arch resection.
Topics: Adult; Humans; Retrospective Studies; Arnold-Chiari Malformation; Platybasia; Joint Dislocations; Atlanto-Axial Joint; Decompression, Surgical; Neck Injuries; Spinal Fusion
PubMed: 37087038
DOI: 10.1016/j.wneu.2023.04.064 -
Journal of Craniovertebral Junction &... 2016For a long time the terms basilar invagination and platybasia were used interchangeably. Basilar invagination has been defined as a prolapse of the vertebral column into...
For a long time the terms basilar invagination and platybasia were used interchangeably. Basilar invagination has been defined as a prolapse of the vertebral column into the spinal cord. Platybasia is defined as an abnormal obtuse angle between the anterior skull base and the clivus. The authors review the existing literature and summarize the historical and modern perspectives in the management of basilar invagination. From radiological curiosities, the subject of basilar invagination is now viewed as eminently treatable. The more pronounced understanding of the subject has taken place in the last three decades when on the basis of understanding of the biomechanical subtleties the treatment paradigm has remarkably altered. From surgery that involved decompression of the region, stabilization and realignment now form the basis of treatment.
PubMed: 36988983
DOI: 10.4103/0974-8237.181856