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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 -
The International Journal of... Mar 2024To report a case of anomalous development of base of skull (platybasia, Basilar invagination and C1-C2 vertebral fusion); and emphasize nonsurgical management in...
AIM
To report a case of anomalous development of base of skull (platybasia, Basilar invagination and C1-C2 vertebral fusion); and emphasize nonsurgical management in inoperable cases that can improve quality of life of the patient.
MATERIALS AND METHODS
The case is reported as a descriptive study of a 17-year-old female who presented to a rural teaching tertiary care hospital in Wardha, Maharashtra, India; with chief complaints of weakness in all four limbs since 10 years of age.
RESULT AND CONCLUSION
Platybasia is a developmental defect of the occipital bone and upper cervical spine resulting from anomalous development. The mechanism of such anomalies is not known; however, the most accepted theory includes abnormal basi-occiput development. The pressure effects may present signs similar to progressive spastic paralysis, cerebellar symptoms, or cranial nerve palsy, in addition to musculoskeletal symptoms. It is, therefore, crucial for physicians and radiologists to be familiar with clinical manifestations and radiological findings. In the following case of a patient with base of skull anomalies, surgical intervention in view of progressive worsening of motor symptoms was advised, however, the guardians declined the same due to high risk involved. Due to financial constraints, genetic studies were unaffordable, and a lack of awareness regarding the disease hampered the guardians from making a decision on the definite management of the disease. Besides radical neurosurgery, intensive physiotherapy can prove vital in significantly improving the quality of life for the patient.
PubMed: 38421185
DOI: 10.1080/00207454.2024.2311234 -
Neurosurgical Review Dec 2023Basilar invagination (BI) is characterized by rostral dislocation of the cervical spine toward the skull base. The craniometrics of the skull base have shown significant...
Basilar invagination (BI) is characterized by rostral dislocation of the cervical spine toward the skull base. The craniometrics of the skull base have shown significant differences among craniocervical junction malformations. The sphenoid bone is the center of the skull base; however, no study has evaluated this bone in cases of BI. This was a cross-sectional study of MRI databanks from two institutions of the author's practice between 1985 and 2020. The craniometrics of the sphenoid bone were measured in BI patients and controls. Fifty-eight MRIs were selected, including 28 BI patients and 30 controls. The mean sphenoid crest-clivus length was 32.66 ± 4.7 mm in the BI group and 29.98 ± 3.0 mm in the control group (p = 0.01). The mean sphenoid planum-top of Dorsum sellae length was 28.53 ± 3.7 mm in the BI group and 26.45 ± 3.2 mm in the control group (p = 0.02). The mean tuberculum sellae-sphenoid floor height was 18.52 ± 4.4 mm in the BI group and 21.32 ± 2.9 mm in the control group (p = 0.00). The mean sella turcica-sphenoid floor height was 10.35 ± 3.8 mm in the BI group and 12.24 ± 3.5 mm in the control group (p = 0.05). The mean clivus length was 29.81 ± 6.3 mm in the BI group and 40.86 ± 4.2 mm in the control group (p = 0.00). The mean sphenoid length was 58.34 ± 7.4 mm in the BI group and 67.31 ± 6.0 mm in the control group (p = 0.00). The mean sphenoid angle was 116.33 ± 8.7° in the BI group and 112.36 ± 6.9° in the control group (p = 0.05). The BI sphenoid bone has shorter vertical dimensions and longer horizontal measures. This morphology promotes a flattening of the sphenoid angle. The sphenoid bone is significantly altered in BI, favoring the congenital hypothesis in the pathophysiology of this disease.
Topics: Humans; Cross-Sectional Studies; Platybasia; Sphenoid Bone; Skull Base; Cervical Vertebrae
PubMed: 38040961
DOI: 10.1007/s10143-023-02227-6 -
Journal of Neurosurgery Feb 2024Craniocervical junction (CCJ) pathologies with ventral neural element compression are poorly understood, and appropriate management requires accurate understanding,...
OBJECTIVE
Craniocervical junction (CCJ) pathologies with ventral neural element compression are poorly understood, and appropriate management requires accurate understanding, description, and a more uniform nomenclature. The aim of this study was to evaluate patients to identify anatomical clusters and better classify CCJ disorders with ventral compression and guide treatment.
METHODS
A retrospective review of adult and pediatric patients with ventral CCJ compression from 2008 to 2022 at a single center was performed. The incidence of anatomical abnormalities and compressive etiologies was assessed. Surgical approach, radiographic data, and outcomes were recorded. Association rules analysis (ARA) was used to assess variable clustering.
RESULTS
Among 51 patients, the main causes of compression were either purely bony (retroflexed dens [n = 18]; basilar invagination [BI; n = 13]) or soft tissue (degenerative pannus [n = 16]; inflammatory pannus [n = 2]). The primary cluster in ARA was a retroflexed dens, platybasia, and Chiari malformation (CM), and the secondary cluster was BI, C1-2 subluxation, and reducibility. These, along with degenerative pannus, formed the three major classes. In assessing the optimal treatment strategy, reducibility was evaluated. Of the BI cases, 12 of the 13 patients had anterolisthesis of C1 that was potentially reducible, compared with 2 of the 18 patients with a retroflexed dens (both with concomitant BI), and no pannus cases. The mean C1-2 facet angle was significantly higher in BI at 32.4°, compared with -2.3° in retroflexed dens and 8.1° in degenerative pannus (p < 0.05). Endonasal decompression with posterior fixation was performed in 48 (94.0%) of the 51 patients, whereas posterior reduction/fixation alone was performed in 3 patients (6.0%). Of 16 reducible cases, open posterior reduction alone was successful in 3 (60.0%) of 5 cases, with all successes containing isolated BI. Reduction was not attempted if vertebral anatomy was unfavorable (n = 9) or the C1 lateral mass was absent (n = 5). The mean follow-up was 28 months. Symptoms improved in 88.9% of patients and were stable in the remaining 11.1%. Tracheostomy and percutaneous G-tube placement occurred in 7.8% and 11.8% of patients, respectively. Reoperation for an endonasal CSF leak repair or posterior cervical wound revision both occurred in 3.9% of patients.
CONCLUSIONS
In classifying, one cluster caused decreased posterior fossa volume due to an anatomical triad of retroflexed dens, platybasia, and CM. The second cluster caused pannus formation due to degenerative hypertrophy. For both, endonasal decompression with posterior fixation was ideal. The third group contained C1 anterolisthesis characterized by a steep C1-2 facet angle causing reducible BI. Posterior reduction/fixation is the first-line treatment when anatomically feasible or endonasal decompression with in situ posterior fixation when anatomical constraints exist.
Topics: Adult; Humans; Child; Platybasia; Decompression, Surgical; Arnold-Chiari Malformation; Odontoid Process; Reoperation
PubMed: 37503952
DOI: 10.3171/2023.5.JNS23677 -
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 Neurological Surgery. Part... Jul 2023There is evidence that Chiari malformation (CM) and basilar invagination (BI) are largely due to disproportion between the content and volume of the posterior fossa....
BACKGROUND
There is evidence that Chiari malformation (CM) and basilar invagination (BI) are largely due to disproportion between the content and volume of the posterior fossa. A recent study identified an increased association between brachycephaly and BI. In several types of craniosynostosis, the posterior fossa volume is smaller than normal, and this is more pronounced in coronal synostosis. The aim of this study is to evaluate the association between CM and BI.
METHODS
The cephalic index (CI) measured on magnetic resonance imaging (MRI) from a sample of patients with craniocervical malformation was compared with that of normal subjects.
RESULTS
The average CI in the craniovertebral junction malformation (CVJM) group was significantly higher in BI patients than in normal subjects. The BI patients also had the highest CI among the whole sample of patients ( = 0.009).
CONCLUSIONS
In this study, BI patients had the highest CI among patients with CVJM and a significantly higher CI than those in the control group. Our data confirm the association between BI and brachycephaly.
Topics: Humans; Platybasia; Arnold-Chiari Malformation; Magnetic Resonance Imaging; Craniosynostoses
PubMed: 34929749
DOI: 10.1055/s-0041-1739503 -
Operative Neurosurgery (Hagerstown, Md.) Apr 2024Patients with basilar invagination (BI) can be treated with several surgical options, ranging from simple posterior decompression to circumferential decompression and...
BACKGROUND AND OBJECTIVES
Patients with basilar invagination (BI) can be treated with several surgical options, ranging from simple posterior decompression to circumferential decompression and fusion. Here, we aimed at examining the indications and outcomes associated with these surgical strategies to devise a staged algorithm for managing BI.
METHODS
We conducted a retrospective cohort study in 2 neurosurgical centers and included patients with a BI, as defined by a position of the dens tip at least 5 mm above the Chamberlain line. Other craniovertebral junction anomalies, such as atlas assimilation, platybasia, and Chiari malformations, were documented. C1-C2 stability was assessed with a dynamic computed tomography scan.
RESULTS
We included 30 patients with BI with a mean follow-up of 56 months (min = 12, max = 166). Posterior decompression and fusion (n = 8) was only performed in cases of obvious atlanto-axial instability (eg, increased atlanto-dental interval or hypermobility on flexion/extension), while anterior decompression (transoral or transnasal) was reserved to patients with lower cranial nerves deficits (eg, swallowing dysfunction) and irreducible anterior compression (n = 9). Patients with posterior signs (eg, Valsalva headaches) or myelopathy but without C1-C2 instability nor anterior signs were managed with an isolated foramen magnum decompression, with or without duraplasty (n = 13). Complications were more frequent for combined procedures, including neurological deterioriation (n = 4) and tracheostomy (n = 2), but reinterventions were more likely in patients undergoing posterior decompression alone (n = 3).
CONCLUSION
Patient selection is key to determine the appropriate surgical strategy for BI: In our experience, combined approaches are only needed for patients with irreducible and symptomatic anterior compression, while fusion should be restricted to patient with obvious signs of atlanto-axial instability. Other BI patients can be managed by foramen magnum decompression alone to minimize surgical morbidity.
PubMed: 38869484
DOI: 10.1227/ons.0000000000001152 -
Clinical Rheumatology Mar 2024
Topics: Humans; Platybasia; Hypoglossal Nerve Diseases; Arthritis, Rheumatoid
PubMed: 38170293
DOI: 10.1007/s10067-023-06863-7 -
World Neurosurgery Jul 2023In this third article in a 3-article series on the craniocervical junction, we define the terms "basilar impression," "cranial settling," "basilar invagination," and...
In this third article in a 3-article series on the craniocervical junction, we define the terms "basilar impression," "cranial settling," "basilar invagination," and "platybasia," noting that these terms are often used interchangeably but represent distinct entities. We then provide examples that represent these pathologies and treatment paradigms. Finally, we discuss the challenges and future direction in the craniovertebral junction surgery space.
Topics: Humans; Platybasia; Skull; Decompression, Surgical
PubMed: 36990348
DOI: 10.1016/j.wneu.2023.03.098 -
Clinical Neurology and Neurosurgery Jul 2023To present our experience with an individualized surgical approach to treat Chiari malformation type 1.
OBJECTIVE
To present our experience with an individualized surgical approach to treat Chiari malformation type 1.
METHODS
Based on (1) neurological symptoms, (2) the existence and extent of a syrinx and (3) the degree of the tonsillar descent we performed four types of approaches on a case-by-case basis in 81 patients: (1) foramen magnum decompression (FMD) with dura splitting (FMDds); (2) FMD with duraplasty (FMDdp); (3) FMD with duraplasty and tonsillar manipulation (FMDao); and (4) tonsillar resection/reduction (TR). Patient characteristics, Chiari Severity Index (CSI), fourth ventricular roof angle (FVRA) and Chicago Chiari Outcome Scale (CCOS) were analyzed.
RESULTS
CCOS was between 13 and 16 points in 8/11 (73 %) patients after FMDds, 38/45 (84 %) patients after FMDdp, and 24/24 (100 %, one patient lost to follow-up) patients after TR. We experienced an overall complication rate of 13.6 % (11/81) in this series, whereas seven of these eleven complications (64 %) occurred in the FMDao group and the complication rate increased with the invasiveness of the approach (0 % FMDds; 4 % FMDdp; 12 % TR).
CONCLUSION
Given the clear correlation between the extend of the approach and the complication rate the least invasive approach necessary to achieve clinical improvement should be selected. Due to the high complication rates, FMDao should not be used as a treatment option. The severity of the tonsillar descent, basilar invagination and current CM1 scores could be used to aid in the approach selection.
Topics: Humans; Treatment Outcome; Decompression, Surgical; Magnetic Resonance Imaging; Arnold-Chiari Malformation; Platybasia; Foramen Magnum; Retrospective Studies
PubMed: 37245455
DOI: 10.1016/j.clineuro.2023.107803