Clinical Application of Quantitative Nursing for Lower Cranial Nerves Injury after Cerebellopontine Angle Tumors

Object. Electromyography (EMG) monitoring is expected to reduce the incidence of motor cranial nerve deficits in cerebellopontine angle surgery. The aim of this study was to provide a detailed analysis of intraoperative EMG phenomena with respect to their surgical significance.Methods. Using a system that continuously records facial and lower cranial nerve EMG signals during the entire operative procedure, the authors examined 30 patients undergoing surgery on acoustic neuroma (24 patients) or meningioma (six patients). Free-running EMG signals were recorded from muscles targeted by the facial, trigeminal, and lower cranial nerves, and were analyzed off-line with respect to waveform characteristics, frequencies, and amplitudes. Intraoperative measurements were correlated with typical surgical maneuvers and postoperative outcomes.Characteristic EMG discharges were obtained: spikes and bursts were recorded immediately following the direct manipulation of a dissecting instrument near the cranial nerve, but also during periods when the nerve had not yet been exposed. Bursts could be precisely attributed to contact activity. Three distinct types of trains were identified: A, B, and C trains. Whereas B and C trains are irrelevant with respect to postoperative outcome, the A train—a sinusoidal, symmetrical sequence of high-frequency and low-amplitude signals—was observed in 19 patients and could be well correlated with additional postoperative facial nerve paresis (in 18 patients).Conclusions. It could be demonstrated that the occurrence of A trains is a highly reliable predictor for postoperative facial palsy. Although some degree of functional worsening is to be expected postoperatively, there is a good chance of avoiding major deficits by warning the surgeon early. Continuous EMG monitoring is superior to electrical nerve stimulation or acoustic loudspeaker monitoring alone. The detailed analysis of EMG-waveform characteristics is able to provide more accurate warning criteria during surgery.

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Rare Tumors of the Cerebellopontine Angle

Otolaryngology ◽

10.1177/019459988008800508 ◽

1980 ◽

Vol 88 (5) ◽

pp. 555-559 ◽

Cited By ~ 182

Author(s):

Derald E. Brackmann ◽

Loren J. Bartels

Keyword(s):

Posterior Fossa ◽

Cerebellopontine Angle ◽

Malignant Tumors ◽

Rapid Development ◽

Cranial Nerves ◽

Benign Tumors ◽

Rare Tumors ◽

Cerebellopontine Angle Tumors ◽

Acoustic Neurinomas ◽

The Subject

In a series of 1,354 cerebellopontine angle tumors treated at the Otologic Medical Croup, approximately 10% were lesions other than acoustic neurinomas. Of the non-acoustic tumors, the majority were meningiomas, primary cholesteatomas, and neurinomas of other cranial nerves in the posterior fossa. Twenty-five other lesions were encountered; these rare tumors are the subject of this study. The benign tumors resemble acoustic neurinomas in appearance and in the method of treatment. Malignant tumors are characterized by rapid development of symptoms and are difficult to treat because of invasion of vital structures in the area.

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Microsurgical Resection of Cerebellopontine Angle Choroid Plexus Papilloma by Far-Lateral Approach. Case Report

JBNC - JORNAL BRASILEIRO DE NEUROCIRURGIA ◽

10.22290/jbnc.v28i3.1673 ◽

2018 ◽

Vol 28 (3) ◽

pp. 193-196

Author(s):

Lucas Crociati Meguins ◽

Dionei Freitas De Morais ◽

Carlos Eduardo Dall’Aglio Rocha ◽

Ricardo Lourenço Caramanti ◽

Thayanna Bentes Lemanski Lopes Rodrigues ◽

...

Keyword(s):

Case Report ◽

Choroid Plexus ◽

Cerebellopontine Angle ◽

Cranial Nerves ◽

Choroid Plexus Papilloma ◽

Lateral Approach ◽

Far Lateral Approach ◽

Far Lateral ◽

Lower Cranial Nerves ◽

Plexus Papilloma

Introduction: Choroid plexus tumors (CPTs) are rare papillary neoplasms derived from choroid plexus epithelium. They account for only approximately 0.4%-0.6% of all intracranial tumors, but 10%-20% of brain tumors occurring throughout the first year of life. Objective: The present study describes the case of an adult man presenting a cerebellopontine angle choroid plexus papilloma (CPP) microsurgically treated through suboccipital far-lateral approach. Case report: A 67-years-old-man was admitted presenting progressive headaches and left lower limb weakness. Magnetic resonance images showed a large tumor on the left cerebellopontine angle with heterogeneous contrast enhancement. Total surgical resection was achieved through a right suboccipital far-lateral craniotomy on lateral position with neurophysiological monitoring of lower cranial nerves. No alterations on cranial nerves function was observed during tumor resection. The patient presented an uneventful recovery and was discharged home on the fifth post-operative day. On the six months follow-up, he was asymptomatic. Anatomopathological analysis confirmed the diagnosis of CPP, WHO grade I. Conclusion: Cerebellopontine angle’s cpp is an extremely rare neoplasm that challenges a neurosurgeon ability to deal with tumor in close relation to lower cranial nerves. Appropriate neurosurgical route, surgeons experience and adequate anatomical knowledge of important neural and vascular structures are fundamental to safely remove CPP of the posterior fossa. Suboccipital far-lateral craniotomy gives enough view with minimal retraction to manage the tumor.

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Cerebellopontine angle metastasis from clear-cell renal carcinoma presenting as bleeding from the ear

The Journal of Laryngology & Otology ◽

10.1017/s0022215100133651 ◽

1996 ◽

Vol 110 (4) ◽

pp. 370-372 ◽

Cited By ~ 9

Author(s):

H. S. Bhatoe ◽

G. U. Deshpande

Keyword(s):

Cerebellopontine Angle ◽

Renal Carcinoma ◽

Clear Cell ◽

Cranial Nerves ◽

Metastatic Lesion ◽

Clear Cell Renal Carcinoma ◽

Clinical Appearance ◽

Metastatic Lesions ◽

Cell Renal Carcinoma ◽

Lower Cranial Nerves

AbstractMetastatic lesions in the cerebellopontine angle are rare. We encountered one such metastatic lesion from clearcell renal carcinoma that had a striking clinical appearance, bleeding from the ear and multiple lower cranial nerves' involvement. While the overall prognosis in CNS metastasis from systemic malignancy is gloomy, useful palliation can be achieved in patients with solitary lesions.

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Endotracheal Tube Electrodes to Assess Vocal Cord Motor Function During Surgery in the Cerebellopontine Angle

Neurosurgery ◽

10.1227/neu.0000000000000854 ◽

2015 ◽

Vol 77 (3) ◽

pp. 471-478

Author(s):

Alexander Romagna ◽

Walter Rachinger ◽

Christoph Schwartz ◽

Jan-Hinnerk Mehrkens ◽

Christian Betz ◽

...

Keyword(s):

At Risk ◽

Vocal Cord ◽

Motor Function ◽

Cerebellopontine Angle ◽

Cranial Nerves ◽

Motor Action ◽

Surface Electrodes ◽

Electrophysiological Recordings ◽

Bipolar Stimulation ◽

Lower Cranial Nerves

AbstractBACKGROUND:The 10th cranial nerve (CN X) is at risk during surgery in the lower cerebellopontine angle (CPA).OBJECTIVE:To evaluate endotracheal surface electrodes for assessment of CN X motor function during CPA surgery.METHODS:Twenty patients were enrolled. Electrophysiological recordings were analyzed and retrospectively correlated with clinical, imaging, and intraoperative data.RESULTS:Recordings from endotracheal surface electrodes were reliable and eligible for analyses in 17 patients; in 3 patients, no surface electrode compound motor action potentials (CMAPs) could be obtained. Those patients with sufficient recordings underwent surgery in the CPA for tumors in 14 patients and for nontumor pathologies in 3 patients. In 12 patients, bipolar stimulation of motor rootlets in the CPA resulted in simultaneous CMAPs recorded from both surface electrodes and needle electrodes placed in the soft palate. Coactivation was particularly seen in patients with an intricate relationship between lower cranial nerves and tumor formations (n = 9/10). Amplitudes and latencies of vocal cord CMAPs showed high interindividual but low intraindividual variability. Parameters were not well correlated with the type of surgery (tumor vs nontumor surgery) and lower CN anatomy (displaced vs undisplaced). In 2 patients, vocal cord CMAPs were lost during tumor surgery, which was associated with postoperative dysphagia and hoarseness in 1 patient.CONCLUSION:Endotracheal surface electrodes allow identification of vocal cord motor rootlets in the CPA. Worsening of CMAP parameters might indicate functional impairment. These aspects support the use of endotracheal surface electrodes in selected patients in whom the vagus nerve might be at risk during CPA surgery.

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Extra-axial cerebellopontine angle cavernoma: A case report and review of literature

Surgical Neurology International ◽

10.25259/sni_664_2020 ◽

2020 ◽

Vol 11 ◽

pp. 386

Author(s):

Bashar Abuzayed ◽

Anas Said ◽

Osama Jamous ◽

Omar Al-Ashqar ◽

Hussein Al-Abadi ◽

...

Keyword(s):

Cerebellopontine Angle ◽

Histopathological Examination ◽

Cranial Nerves ◽

Downbeat Nystagmus ◽

Hemosiderin Deposition ◽

Intraoperative Management ◽

Level Of Consciousness ◽

Axial Mass ◽

The Right ◽

Lower Cranial Nerves

Background: Extra-axial cavernomas at the cerebellopontine angle (CPA) are rare clinical entity that can radiologically mimic several lesions encountered at this location. Case Description: A 36-year-old female patient referred to our emergency service with acute decreased level of consciousness and vomiting. Neurological examination showed Glasgow Coma Scale of 12 with downbeat nystagmus of the right eye. Brain computed tomography scan and magnetic resonance imaging showed multilobulated extra-axial mass lesion located in the right CPA. The lesion was with various signal intensities in T1- and T2-weighted images suggestive of hemorrhages of different ages. T2 gradient echo sequences showed multiple sinusoid-like channels and diffuse hemosiderin deposition. These figures were compatible with cavernous malformation. The patient was operated by retrosigmoid approach. Dissection of the mass from the trigeminal, facial, vestibulocochlear, and lower cranial nerves was performed and total resection of the tumor was achieved. Histopathological examination confirmed the diagnosis of cavernoma. Conclusion: Although CPA cavernomas are very rare, they should be considered for differential diagnosis when evaluating CPA lesions preoperatively for better intraoperative management and postoperative outcomes.

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