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World Neurosurgery Dec 2014To describe the technical and anatomic nuances related to endoscopic endonasal approaches (EEAs) to the paramedian skull base. (Review)
Review
OBJECTIVE
To describe the technical and anatomic nuances related to endoscopic endonasal approaches (EEAs) to the paramedian skull base.
METHODS
Surgical indications, limitations, and technical aspects pertaining to EEAs designed to access areas oriented in the coronal plane are systematically reviewed with special attention to caveats, pitfalls, and common complications and how to avoid them. Case examples are presented.
RESULTS
The paramedian skull base may be divided into anterior (corresponding to the orbit and its contents), middle (corresponding to the middle cranial, pterygopalatine, and infratemporal fossae), and posterior (includes the craniovertebral junction lateral to the occipital condyles and the jugular foramen) segments. EEAs to the anterior segment offer access to the intraconal orbital space and the optic canal. A transpterygoid corridor typically precedes EEAs to the middle and posterior paramedian approaches. EEAs to the middle segment provide wide exposure of the petrous apex, middle cranial fossa (including cavernous sinus and Meckel cave), and infratemporal and pterygopalatine fossae. Finally, EEAs to the posterior segment access the hypoglossal canal, occipital condyle, and jugular foramen.
CONCLUSIONS
Approaches to the paramedian skull base are the most challenging and complex of all endoscopic endonasal techniques. Because of their technical complexity, it is recommended that surgeons master endoscopic endonasal anatomic approaches oriented to median structures (sagittal plane) before approaching paramedian (coronal plane) pathologies.
Topics: Endoscopy; Humans; Nasal Cavity; Neurosurgical Procedures; Postoperative Complications; Skull Base
PubMed: 25496623
DOI: 10.1016/j.wneu.2014.07.036 -
Insights Into Imaging Mar 2019Paragangliomas arise from paraganglion cells which serve varied regulatory tasks in the body. When these cells demonstrate neoplasia within the head and neck, they... (Review)
Review
Paragangliomas arise from paraganglion cells which serve varied regulatory tasks in the body. When these cells demonstrate neoplasia within the head and neck, they typically present in characteristic locations including the carotid space, the jugular foramen, the middle ear, and along the course of the vagus nerve. The goal of this article is to review the relevant anatomy related to head and neck paragangliomas, as well as their typical imaging characteristics on cross-sectional imaging including CT, MR, ultrasound, and nuclear medicine studies. Additionally, differential considerations, as well as relevant involvement of adjacent structures which should be conveyed to the clinician, will be discussed.
PubMed: 30830483
DOI: 10.1186/s13244-019-0701-2 -
Neuro-Chirurgie Sep 2021The retrolabyrinthine approach is classified among the posterior petrosectomies. Its goal is to achieve an enlarged mastoidectomy while sparing the intrapetrous...
BACKGROUND
The retrolabyrinthine approach is classified among the posterior petrosectomies. Its goal is to achieve an enlarged mastoidectomy while sparing the intrapetrous neurotologic structures in order to offer maximal exposure of the posterior cerebellopontine angle compound.
METHODS
The stages of the procedure are subsequently the skeletonization of the sigmoid sinus, wide opening of the mastoid antrum and exposure of the semicircular canals. We present herein the technique, indications and limitations of the retrolabyrinthine approach.
CONCLUSION
The retrolabyrinthine approach is a demanding technique. Nowadays the retrolabyrinthine approach is routinely combined to additional resections of the petrous bone, so-called "combined petrosectomies", to target the jugular foramen or the petroclival area.
Topics: Cerebellopontine Angle; Craniotomy; Humans; Petrous Bone
PubMed: 33493539
DOI: 10.1016/j.neuchi.2021.01.008 -
BioMedicine 2023Differentiating jugular foramen from hypoglossal canal in computed tomography (CT) scan is vital for correct diagnosis of posterior fossa pathologies; however, it has...
BACKGROUND
Differentiating jugular foramen from hypoglossal canal in computed tomography (CT) scan is vital for correct diagnosis of posterior fossa pathologies; however, it has been shown that the ability for differentiating these skull base elements is limited. The purpose of this study was to produce a simple algorithm for differentiating the jugular foramen from the hypoglossal canal in axial CT scan on two levels (top level where bony carotid canal is evident and lower level where bony carotid canal is not evident).
METHODS
Data derived from axial CT scan of 250 patients (500 sides) were used for producing algorithm. At top level petro-occipital fissure utilized for recognizing occipital condyle in which hypoglossal canal is located; and, at lower level the distance between the posterior border of the anatomic element (jugular foramen or hypoglossal canal) and the tangent to the anterior bony part is used for producing algorithm.
RESULTS
The mean age of patients was 38.1 ± 19 years. The petro-occipital fissure can be used in all patients for differentiating hypoglossal canal. At lower level the distance between the anterior tangent and the posterior border of the element was significantly lower for hypoglossal canal (P value < 0.001). The distance more than 3.5 mm with sensitivity 83.8% and specificity 97.1% differentiate jugular foramen from hypoglossal canal.
CONCLUSION
Simple algorithms based on quantitative morphologic features of the jugular foramen and hypoglossal canal can be used with high sensitivity and specificity to distinguish these elements.
PubMed: 37168727
DOI: 10.37796/2211-8039.1393 -
Radiology Case Reports Aug 2022Adenoid cystic carcinoma is a slowly growing malignant tumor with high local recurrence, perineural and vascular invasion. This tumor might arise from the glands of...
Adenoid cystic carcinoma is a slowly growing malignant tumor with high local recurrence, perineural and vascular invasion. This tumor might arise from the glands of upper respiratory tract and oral cavity (eg, salivary or serous or mucous). Here we report the case of a 65-year-old woman who was referred to our unit for left retro-auricular radiating pain with trigger points and frontal headache since 6 months. There was no involvement of cranial nerves. Imaging screening using MRI, Positron emission tomography with 2-[fluorine-18] fluoro-2-deoxy-D-glucose, Gallium-68 DOTA-Phe1-Tyr3-Octreotide (68Ga DOTATOC) Positron emission tomography-CT suggested a suspicion of schwannoma or paraganglioma of the jugular foramen. However, the CT-guided biopsy revealed presence of adenoid cystic carcinoma. These warrants performing mandatory histological analysis combined with imaging screening suspicion of schwannoma or paraganglioma.
PubMed: 35663812
DOI: 10.1016/j.radcr.2022.04.046 -
Child's Nervous System : ChNS :... Oct 2021The knowledge of the development and the anatomy of the posterior cranial fossa (PCF) is crucial to define the occurrence and the prognosis of diseases where the surface... (Review)
Review
BACKGROUND
The knowledge of the development and the anatomy of the posterior cranial fossa (PCF) is crucial to define the occurrence and the prognosis of diseases where the surface and/or the volume of PCF is reduced, as several forms of craniosynostosis or Chiari type I malformation (CIM). To understand the functional and morphological changes resulting from such a hypoplasia is mandatory for their correct management. The purpose of this article is to review the pertinent literature to provide an update on this topic.
METHODS
The related and most recent literature addressing the issue of the changes in hypoplasic PCF has been reviewed with particular interest in the studies focusing on the PCF characteristics in craniosynostosis, CIM, and achondroplasia.
RESULTS AND CONCLUSIONS
In craniosynostoses, namely, the syndromic ones, PCF shows different degrees of hypoplasia, according to the different pattern and timing of early suture fusion. Several factors concur to PCF hypoplasia and contribute to the resulting problems (CIM, hydrocephalus), as the fusion of the major and minor sutures of the lambdoid arch, the involvement of the basal synchondroses, and the occlusion of the jugular foramina. The combination of these factors explains the variety of the clinical and radiological phenotypes. In primary CIM, the matter is complicated by the evidence that, in spite of impaired PCF 2D measurements and theories on the mesodermal defect, the PCF volumetry is often comparable to healthy subjects. CIM is revealed by the overcrowding of the foramen magnum that is the result of a cranio-cerebral disproportion (altered PCF brain volume/PCF total volume). Sometimes, this disproportion is evident and can be demonstrated (basilar invagination, real PCF hypoplasia); sometimes, it is not. Some recent genetic observations would suggest that CIM is the result of an excessive growth of the neural tissue rather than a reduced growth of PCF bones. Finally, in achondroplasia, both macrocephaly and reduced 2D and 3D values of PCF occur. Some aspects of this disease remain partially obscure, as the rare incidence of hydrocephalus and syringomyelia and the common occurrence of asymptomatic upper cervical spinal cord damage. On the other hand, the low rate of CIM could be explained on the basis of the reduced area of the foramen magnum, which would prevent the hindbrain herniation.
Topics: Arnold-Chiari Malformation; Cranial Fossa, Posterior; Craniosynostoses; Humans; Hydrocephalus; Magnetic Resonance Imaging; Syringomyelia
PubMed: 34169386
DOI: 10.1007/s00381-021-05193-w -
Journal of Neurological Surgery. Part... Jun 2022Proposed landmarks to predict the anatomical location and trajectory of the sigmoid sinus have varying degrees of reliability. Even with neuronavigation technology,...
Proposed landmarks to predict the anatomical location and trajectory of the sigmoid sinus have varying degrees of reliability. Even with neuronavigation technology, landmarks are crucial in planning and performing complex approaches to the posterolateral skull base. By combining two major dependable structures-the asterion (A) and transverse process of the atlas (TPC1)-we investigate the A-TPC1 line in relation to the sigmoid sinus and in partitioning surgical approaches to the region. We dissected six cadaveric heads (12 sides) to expose the posterolateral skull base, including the mastoid and suboccipital bone, TPC1 and suboccipital triangle, distal jugular vein and internal carotid artery, and lower cranial nerves in the distal cervical region. We inspected the A-TPC1 line before and after drilling the mastoid and occipital bones and studied the relationship of the sigmoid sinus trajectory and major muscular elements related to the line. We retrospectively reviewed 31 head and neck computed tomography (CT) angiograms (62 total sides), excluding posterior fossa or cervical pathologies. Bone and vessels were reconstructed using three-dimensional segmentation software. We measured the distance between the A-TPC1 line and sigmoid sinus at different levels: posterior digastric point (DP), and maximal distances above and below the digastric notch. A-TPC1 length averaged 65 mm and was posterior to the sigmoid sinus in all cadaver specimens, coming closest at the level of the DP. Using the transverse-asterion line as a rostrocaudal division and skull base as a horizontal plane, we divided the major surgical approaches into four quadrants: distal cervical/extreme lateral and jugular foramen (anteroinferior), presigmoid/petrosal (anterosuperior), retrosigmoid/suboccipital (posterosuperior), and far lateral/foramen magnum regions (posteroinferior). Radiographically, the A-TPC1 line was also posterior to the sigmoid sinus in all sides and came closest to the sinus at the level of DP (mean, 7 mm posterior; range, 0-18.7 mm). The maximal distance above the DP had a mean of 10.1 mm (range, 3.6-19.5 mm) and below the DP 5.2 mm (range, 0-20.7 mm). The A-TPC1 line is a helpful landmark reliably found posterior to the sigmoid sinus in cadaveric specimens and radiographic CT scans. It can corroborate the accuracy of neuronavigation, assist in minimizing the risk of sigmoid sinus injury, and is a useful tool in planning surgical approaches to the posterolateral skull base, both preoperatively and intraoperatively.
PubMed: 35832953
DOI: 10.1055/s-0041-1731032 -
Current Opinion in Otolaryngology &... Oct 2018To review the current literature on the extended middle cranial fossa (xMCF) approach and to provide a comprehensive description of the relevant anatomy, indications,... (Review)
Review
PURPOSE OF REVIEW
To review the current literature on the extended middle cranial fossa (xMCF) approach and to provide a comprehensive description of the relevant anatomy, indications, surgical technique, results, and complications.
RECENT FINDINGS
The xMCF approach expands the surgical exposure provided by the sMCF approach, allowing access to the internal auditory canal, cerebellopontine angle, prepontine cistern, anterior petrous apex, petrous carotid artery, Meckel's cave, cavernous sinus, mid and upper clivus, and posterior lesions approaching the jugular foramen. Preservation of serviceable hearing is possible with success rates approximating 50% in vestibular schwannoma and meningioma resection, and facial nerve outcome is excellent.
SUMMARY
The xMCF is an important approach for difficult to access lesions that additionally offers the possibility of hearing preservation. This approach is also useful for vascular lesions, auditory brainstem implantation, and lesions of mid-brainstem.
Topics: Cranial Fossa, Middle; Craniotomy; Hearing Loss; Humans; Intracranial Aneurysm; Meningioma; Neuroma, Acoustic
PubMed: 29957681
DOI: 10.1097/MOO.0000000000000471 -
Journal of Cerebrovascular and... Dec 2020Jugular foramen paragangliomas (JFP) are benign tumors of neural crest origin that are located along the temporal bone in the region of the jugular bulb and middle ear....
Jugular foramen paragangliomas (JFP) are benign tumors of neural crest origin that are located along the temporal bone in the region of the jugular bulb and middle ear. The optimal management of these lesions includes surgical excision with or without preoperative embolization as well as stereotactic radiotherapy. The use of preoperative embolization in the treatment of JFP has shown great promise to bridge patients to surgery by diminishing complication rates and decreasing intraoperative bleeding. We present three successful polyvinyl alcohol (PVA) particle embolizations of patients presenting with symptomatic JFPs. All patients recovered completely in the short term with no bleeding during or after resection of paragangliomas and they were discharged free of their presenting symptoms. Early clinical and imaging diagnosis followed by adequate treatment including preoperative transcatheter particle embolization and surgical or radiosurgical interventions can lead to excellent outcomes.
PubMed: 33334087
DOI: 10.7461/jcen.2020.E2019.09.033