Guidelines for Brainstem Surgery with Functional Preservation(<SPECIAL ISSUES> Preservation of the Cranial Nerves)

Abstract BACKGROUND: Damage to the motor division of the lower cranial nerves that run into the jugular foramen leads to hoarseness, dysphagia, and the risk of aspiration pneumonia; therefore, its functional preservation during surgical procedures is important. Intraoperative mapping and monitoring of the motor rootlets at the cerebellomedullary cistern using endotracheal tube electrodes is a safe and effective procedure to prevent its injury. OBJECTIVE: To study the location of the somatic and autonomic motor fibers of the lower cranial nerves related to vocal cord movement. METHODS: Twenty-four patients with pathologies at the cerebellopontine lesion were studied. General anesthesia was maintained with fentanyl and propofol. A monopolar stimulator was used at amplitudes of 0.05 to 0.1 mA. Both acoustic and visual signals were displayed as vocalis muscle electromyographic activity using endotracheal tube surface electrodes. RESULTS: The average number of rootlets was 7.4 (range, 5-10); 75% of patients had 7 or 8 rootlets. As many as 6 rootlets (2-4 in most cases) were responsive in each patient. In 23 of the 24 patients, the responding rootlets congregated on the caudal side. The maximum electromyographic response was predominantly in the most caudal or second most caudal rootlet in 79%. CONCLUSION: The majority of motor fibers of the lower cranial nerves run through the caudal part of the rootlets at the cerebellomedullary cistern, and the maximal electromyographic response was elicited at the most caudal or second most caudal rootlet.

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Microsurgical anatomy and internal architecture of the brainstem in 3D images: surgical considerations

Journal of Neurosurgery ◽

10.3171/2015.4.jns132778 ◽

2016 ◽

Vol 124 (5) ◽

pp. 1377-1395 ◽

Cited By ~ 14

Author(s):

Richard Gonzalo Párraga ◽

Lucas Loss Possatti ◽

Raphael Vicente Alves ◽

Guilherme Carvalhal Ribas ◽

Uğur Türe ◽

...

Keyword(s):

Cranial Nerves ◽

Surgical Approaches ◽

Detailed Knowledge ◽

Microsurgical Anatomy ◽

Descending Pathways ◽

Brainstem Surgery ◽

Point Of Entry ◽

Cerebellar Peduncles ◽

Dissection Technique ◽

Internal Architecture

OBJECT Brainstem surgery remains a challenge for the neurosurgeon despite recent improvements in neuroimaging, microsurgical techniques, and electrophysiological monitoring. A detailed knowledge of the microsurgical anatomy of the brainstem surface and its internal architecture is mandatory to plan appropriate approaches to the brainstem, to choose the safest point of entry, and to avoid potential surgical complications. METHODS An extensive review of the literature was performed regarding the brainstem surgical approaches, and their correlations with the pertinent anatomy were studied and illustrated through dissection of human brainstems properly fixed with 10% formalin. The specimens were dissected using the fiber dissection technique, under ×6 to ×40 magnification. 3D stereoscopic photographs were obtained (anaglyphic 3D) for better illustration of this study. RESULTS The main surgical landmarks and their relationship with the cerebellum and vascular structures were identified on the surface of the brainstem. The arrangements of the white matter (ascending and descending pathways as well as the cerebellar peduncles) were demonstrated on each part of the brainstem (midbrain, pons, and medulla oblongata), with emphasis on their relationships with the surface. The gray matter, constituted mainly by nuclei of the cranial nerves, was also studied and illustrated. CONCLUSIONS The objective of this article is to review the microsurgical anatomy and the surgical approaches pertinent to the brainstem, providing a framework of its external and internal architecture to guide the neurosurgeon during its related surgical procedures.

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10. Surgery for the Brainstem and its Functional Preservation(Part 2:Cranial nerves and their preservation, PS1-1 Functional Mapping/Monitoring in Neurosurgical Management, The 27^ Annual Meeting of The Japanese Congress of Neurological Surgeons)

Japanese Journal of Neurosurgery ◽

10.7887/jcns.16.310_3 ◽

2007 ◽

Vol 16 (4) ◽

pp. 310

Author(s):

Kazuhiro Hongo

Keyword(s):

Annual Meeting ◽

Cranial Nerves ◽

Functional Mapping ◽

Functional Preservation

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Functional outcome after surgical treatment of cavernous malformation involving ocular motor cranial nerves: A systematic review

10.21203/rs.3.rs-17662/v1 ◽

2020 ◽

Author(s):

Kyoung Su Sung ◽

Jaejoon Lim ◽

So Jung Hwang ◽

Duk-Hee Chun ◽

KYUNGGI CHO

Keyword(s):

Systematic Review ◽

Surgical Treatment ◽

Cavernous Malformation ◽

Cranial Nerves ◽

Ocular Motor ◽

Cavernous Malformations ◽

Functional Changes ◽

Preservation Method ◽

Surgical Methods ◽

Functional Preservation

Abstract Background: Cavernous malformations (CMs) of cranial nerves (CN) III, IV, and VI are extremely rare, and limited studies have assessed the functional outcomes after treatment. This systematic review investigated the clinical features of CMs in ocular motor CNs, including treatment results, and compared different surgical methods for functional preservation of ocular motor CNs. Methods: ‘PubMed’, ‘SCOPUS’, ‘Web of Science’, and ‘Google Scholar’ databases were searched to identify case reports and studies published between January 1980 and December 2018. This systematic review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Results: Twenty-seven patients were identified (median age, 46 years; range, 3 months-71 years). CN III was involved in 17 patients (63.0%), CN IV in 8 (29.6%), and CN VI in 2 (7.4%). Treatments included gross total resection (GTR) and nerve transection in 6 patients (22.2%), GTR and nerve continuity preservation in 7 (25.9%), subtotal resection (STR) and nerve continuity preservation in 4 (14.8%), GTR and end-to-end anastomosis in 5 (18.5%), and conservative care in 3 (11.1%), while the treatment method for 2 (7.4%) patients was not described in the literature. In 22 patients who underwent surgical treatment, functional changes included improvement in 9 patients (40.9%), no change in 10 (45.5%), and worsening symptoms in 3 (13.6%). Functional preservation was achieved in 12 (54.5%) of the 22 patients; the nerve continuity preservation method conferred significant advantage for functional preservation compared with other surgical methods ( p =0.004). Conclusion: Functional preservation of ocular motor CNs can be achieved by nerve continuity preservation. Key Words: cavernous malformation; cranial nerve; treatment outcome

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Human Neurofibromas in Co-Culture with Mouse Neurons

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053632 ◽

1982 ◽

Vol 40 ◽

pp. 194-195

Author(s):

R.L. Martuza ◽

T. Liszczak ◽

A. Okun ◽

T-Y Wang

Keyword(s):

Schwann Cell ◽

Schwann Cells ◽

Genetic Disorder ◽

Cranial Nerves ◽

Sympathetic Nerves ◽

Acoustic Neuromas ◽

Spinal Roots ◽

Neural Crest Origin ◽

Multiple Abnormalities ◽

Other Neoplasms

Neurofibromatosis (NF) is an autosomal dominant genetic disorder with a prevalence of 1/3,000 births. The NF mutation causes multiple abnormalities of various cells of neural crest origin. Schwann cell tumors (neurofibromas, acoustic neuromas) are the most common feature of neurofibromatosis although meningiomas, gliomas, and other neoplasms may be seen. The schwann cell tumors commonly develop from the schwann cells associated with sensory or sympathetic nerves or their ganglia. Schwann cell tumors on ventral spinal roots or motor cranial nerves are much less common. Since the sensory neuron membrane is known to contain a mitogenic factor for schwann cells, we have postulated that neurofibromatosis may be due to an abnormal interaction between the nerve and the schwann cell and that this interaction may be hormonally modulated. To test this possibility a system has been developed in which an enriched schwannoma cell culture can be obtained and co-cultured with pure neurons.

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