Brainstem In Patients Research Articles

Observation of harmonic vestibulosomatic reactions in a patient with demyelinating lesion in the medulla oblongata region at the level of vestibular nuclei

The article is devoted to the problems of differential diagnosis of central and peripheral vestibular dysfunctions. Authors discuss the case of the so-called “pseudo-acute peripheral vestibulopathy” described in literature sources. The authors observe peripheral vestibular symptoms (horizontal–torsional contralesional spontaneous nystagmus and harmonic nature of axial lateropulsion during the study of equilibrium) in a patient with central vestibular disorder genesis – demyelinating disease in the region of the vestibular nuclei in the brain stem, confirmed by magnetic resonance imaging. The data of vestibular testing and the results of spontaneous nystagmus study by means of video-oculography are analyzed. The authors bring up the issue of the necessity of more careful exclusion of lesions in the area of the vestibular nuclei of the brain stem in patients with the signs of peripheral vestibular dysfunction, especially when they are accompanied by the central vestibular symptomatology.

Atlantoaxial Joint Distraction with a New Expandable Device for the Treatment of Basilar Invagination with Preservation of the C2 Nerve Root: A Cadaveric Anatomical Study.

Atlantoaxial joint distraction has been advocated for the decompression of the brain stem in patients affected by basilar invagination, avoiding direct transoral decompression. This technique requires C2 ganglion resection and it is often impossible to perform due to the peculiar bony anatomy. We describe a cadaveric anatomical study supporting the feasibility of C1-C2 distraction performed with an expandable device, allowing easier insertion of the tool and preservation of the C2 nerve root. In five adult cadaveric specimens, posterior atlantoaxial surgical exposure was performed and an expandable system was inserted within the C1-C2 joint. The expansion of the device, leading to active distraction of the joint space, together with all the surgical steps of the technique was recorded with anatomical pictures and the final results were checked with a computed tomography (CT) scan. Insertion of the device was easily performed in all cases without anatomical conflict with the C2 ganglion; CT scans confirmed the distraction of the C1-C2 joint. This cadaveric anatomical study confirms the feasibility of the introduction of an expandable and flexible device within the C1-C2 joint, allowing it's distraction and preservation of the C2 ganglion.

On the distribution of intranuclear and cytoplasmic aggregates in the brainstem of patients with spinocerebellar ataxia type 2 and 3.

The polyglutamine (polyQ) diseases are a group of genetically and clinically heterogeneous neurodegenerative diseases, characterized by the expansion of polyQ sequences in unrelated disease proteins, which form different types of neuronal aggregates. The aim of this study was to characterize the aggregation pathology in the brainstem of spinocerebellar ataxia type 2 (SCA2) and 3 (SCA3) patients. For good recognition of neurodegeneration and rare aggregates, we employed 100 µm PEG embedded brainstem sections, which were immunostained with the 1C2 antibody, targeted at polyQ expansions, or with an antibody against p62, a reliable marker of protein aggregates. Brainstem areas were scored semiquantitatively for neurodegeneration, severity of granular cytoplasmic staining (GCS) and frequency of neuronal nuclear inclusions (NNI). SCA2 and SCA3 tissue exhibited the same aggregate types and similar staining patterns. Several brainstem areas showed statistically significant differences between disease groups, whereby SCA2 showed more severe GCS and SCA3 showed more numerous NNI. We observed a positive correlation between GCS severity and neurodegeneration in SCA2 and SCA3 and an inverse correlation between the frequency of NNI and neurodegeneration in SCA3. Although their respective disease proteins are unrelated, SCA2 and SCA3 showed the same aggregate types. Apparently, the polyQ sequence alone is sufficient as a driver of protein aggregation. This is then modified by protein context and intrinsic properties of neuronal populations. The severity of GCS was the best predictor of neurodegeneration in both disorders, while the inverse correlation of neurodegeneration and NNI in SCA3 tissue implies a protective role of these aggregates.

Diffusion tensor imaging assessment of microstructural brainstem integrity in Chiari malformation Type I.

OBJECTIVE The diagnosis of Chiari malformation Type I (CM-I) is primarily based on the degree of cerebellar tonsillar herniation even though it does not always correlate with symptoms. Neurological dysfunction in CM-I presumably results from brainstem compression. With the premise that conventional MRI does not reveal brain microstructural changes, this study examined both structural and microstructural neuroimaging metrics to distinguish patients with CM-I from age- and sex-matched healthy control subjects. METHODS Eight patients with CM-I and 16 controls were analyzed. Image postprocessing involved coregistration of anatomical T1-weighted with diffusion tensor images using 3D Slicer software. The structural parameters included volumes of the posterior fossa, fourth ventricle, and tentorial angle. Fractional anisotropy (FA) was calculated separately in the anterior and posterior compartments of the lower brainstem. RESULTS The mean age of patients in the CM-I cohort was 42.6 ± 10.4 years with mean tonsillar herniation of 12 mm (SD 0.7 mm). There were no significant differences in the posterior fossa volume (p = 0.06) or fourth ventricular volume between the 2 groups (p = 0.11). However, the FA in the anterior brainstem compartment was significantly higher in patients with CM-I preoperatively (p = 0.001). The FA values normalized after Chiari decompression except for persistently elevated FA in the posterior brainstem compartment in patients with CM-I and syrinx. CONCLUSIONS In this case-control study, microstructural alterations appear to be reliably associated with the diagnosis of CM-I, with a significantly elevated FA in the lower brainstem in patients with CM-I compared with controls. More importantly, the FA values normalized after decompressive surgery. These findings should be validated in future studies to determine the significance of diffusion tensor imaging-based assessment of brainstem microstructural integrity as an adjunct to the clinical assessment in patients with CM-I.

Frontonasal dysplasia: clinical evaluation on audiological and brainstem electrophysiological profiles

AbstractFrontonasal dysplasia (FND) is a rare malformative complex affecting the frontal portion of the face, the eyes and the nose; it may occur singly or associated with other clinical signs. No systematic studies describing hearing in this condition were found. AimTo evaluate hearing sensitivity and sound stimulus conduction from cochlea to brainstem in patients with clinical signs of FND. Methods21 patients with isolated or syndromic FND were submitted to a clinical (otological/ vestibular antecedents and otoscopy) and instrumental (pure tone and speech audiometry, tympanometry and brainstem auditory evoked response) hearing evaluation. DesignA clinical, cross-sectional observational prospective study. ResultsHearing thresholds were normal in 15 (70%) patients, abnormal in 5 (25%), mostly with conductive hearing loss; one patient did not cooperate with testing. The tympanometric curve was type A in 30 (72%) ears, type C in 5 (12%), type As in 4 (9%) and type B in 3 (7%). The auditory brainstem response (ABR) showed no abnormalities. ConclusionPatients with FND showed no abnormalities in the auditory system from cochlea to brainstem in this study. Mild conductive hearing loss found in some is probably related to cleft palate. Further evaluation of hearing pathways at higher levels is recommended.

Semiological and electroencephalographic features of epilepsy with amygdalar lesion

To identify semiological and scalp/sphenoidal electroencephalographic (EEG) features of epilepsy with amygdalar lesion (AL). This study included 17 patients with epilepsy and distinct AL on MRI, who underwent resective surgery. There were nine female and eight male patients with ages at surgery ranging from 8 to 48 (mean 26.3) years. Postoperative seizure outcome was Engel class I or seizure-free in 12 patients, class II in four, and class III in one. Pathological examination revealed dysembryoplastic neuroepithelial tumor in eight cases, astrocytoma in two, mixed oligoastrocytoma in three, ganglioglioma in two, localized encephalitis in one, and cortical dysplasia in one. Semiology and scalp/sphenoidal EEG findings of these patients (AL group) were compared with those of 20 mesial temporal lobe epilepsy patients with hippocampal sclerosis (HS) who underwent resective surgery with favorable seizure outcome (Engel class I) (control group). Increased tonic components during seizure were more frequently seen in AL group (58.8%) than in control group (20%). Interictal unitemporal slow waves were more frequently found in AL group (58.8%) than in control group (20%). Ictal EEG revealed generalized (not only bitemporal) onset in six patients in AL group (35.3%), but none in control group. The generalized EEG onset patterns in AL group included spike and wave complexes, rhythmic spikes, and delta waves. Patients with AL had increased tonic components during seizure and generalized ictal EEG onset more frequently than patients with HS. These findings suggest widespread epileptic network involving subcortical structures such as the thalamus and the brainstem in patients with AL.

The change in auditory evoked potentials of brainstem in patients with skull base fracture and hypoacusia

The change in auditory evoked potentials of brainstem in patients with skull base fracture and hypoacusia

Significance of brain stem auditory evoked potential and somatosensory evoked potential on prognosis evaluation in patients with acute cerebral infarction

Objective To investigate changes of brainstem auditory evoked potential (BAEP)and somatosensory evoked potential (SEP) in patients with acute cerebral infarction,and discuss their relation with prognosis of the patients.Methods The study involved 60 patients with acute cerebral infarction.Changes of BAEP and SEP in each patient were detected and recorded continuously.Prognosis evaluation was performed by using GCS.Another 60 age-matched and gender-matched healthy human beings were enrolled as controls.Results Incubation period of BAEP wave Ⅰ had no significant difference between the cerebral infarction and control groups (P ＞ 0.05).However,interspike intervals of other BAEP waves in cerebral infarction group were different from those in control group (P ＜ 0.05).A series of waves of SEP (P14-N60) were all significantly prolonged in cerebral infarction group (P ＜0.05).Conclusion BAEP and SEP can effectively reflect function of brain stem in patients with acute cerebral infarction and have some values in determining their prognosis. Key words: Brain injuries; Evoked potential,auditory; Evoked potential,somatosensory; Acute cerebral infarction

Reply: Levodopa increases functional connectivity in the cerebellum and brainstem in Parkinson’s disease

ARTICLE Sir, Jech et al. (2013) report that l-DOPA increased functional connectivity in the cerebellum and brainstem of patients with moderately severe Parkinson’s disease. This result is broadly complementary to our recent demonstration that functional connectivity between the striatum and a large region encompassing brainstem and cerebellum is abnormally decreased in advanced Parkinson’s disease compared with age-matched control subjects, despite continued treatment with l-DOPA (Hacker et al. , 2012). Whereas Jech et al. (2013) did not compare patients with Parkinson’s disease to control subjects, we did not study the effects of …

Antigens diagnoses in paraneoplastic neurological syndromes.

10582 Background: At present, paraneoplasmatic neurological syndroms (PNS) are thought to be autoimmunological disorders. Neurological symptoms in PNS result from the disturbance of the nervous system, with a participation of the immune response triggered by the aberrant expression of the so-called onconeuronal antigens of a tumour. Very important for PNS diagnostics is the investigation of antineuronal antibodies (ANA) in the serum. Different types of ANA are frequently associated with specific tumors and with specific neurological syndromes.Investigations of serum ANA in patients with breast cancer with the symptoms of PNS. Methods: Investigations of ANA in serum were performed with the indirect immunofluorescence test but the type of ANA was analyzed by the Western Blot (WB) method . The presence of these antibodies which are included to the group of “the so called well characterized” is believed to be a definite (95 – 100%) determinant of the PNS diagnosis. Results: We examined 147 patients with breast cancer suspected to have PNS, hospitalized at Breast Cancer Clinic of the Institute of Oncology in Warsaw. The immunofluorescence test was positive in 92 patients, however in 24 patients the WB occurrence of “the well characterized” antibodies was found. In this group we observed: in 4 patients the cerebellar degeneration (anti-Yo, anti-Ma2); in 6 patients brainstem encephalitis and encephalomyelitis combined with sensory neuropathy (anti-Ma2, anti-CV2, anti-Yo, anti-Hu, anti-Ri); 4 myastenic syndrome (anti-Hu,anti-Ri,anti-Ma2/Ta); 5 sensory neuropathy (anti-Hu, anti-Yo, anti-Ma2, anti-Ri); and in single cases we also observed polyneuropathy: Guillain-Barre (Ma2): Miller-Fisher syndrom (anti-Ma2/Ta); cancer-associated retinopathy (anti-Yo); dermatomyositis (anti-Ri) and scleroderma (anti-Yo). Conclusions: Our analysis indicates that the investigation of the presence of ANA in the serum is the important in the diagnosis of PNS in patients with breast cancer. The types of ANA correspond to the individual paraneoplastic neurological syndromes which opens the proper methods of treatment in PNS.

Abnormal Axial Diffusivity in the Deep Gray Nuclei and Dorsal Brain Stem in Infantile Spasm Treated with Vigabatrin

We evaluated the DTI changes in the deep gray nuclei and dorsal brain stem, which demonstrated abnormal T2 and/or diffusion signal intensity, in 6 patients with infantile spasm treated with vigabatrin compared with 6 age-matched controls. Regions of interest were placed in the globi pallidi, thalami, and dorsal brain stem; FA, trace, D(‖), and D(⊥) were measured. Patients on vigabatrin had significantly lower FA in both globi pallidi (P = .01) and the dorsal brain stem (P < .01), significantly lower trace in both globi pallidi (P = .01) and the thalami (P = .02 and .01 for right and left, respectively), and significantly lower D(‖) in both globi pallidi (P ≤ .01), the thalami (P < .01), and the dorsal brain stem (P = .03). There were no significant differences in D(⊥) of the globi pallidi, thalami, or dorsal brain stem in patients compared with controls. The findings suggest that axonal changes play a greater role in the observed abnormal signal intensity, with lesser contribution from myelin changes.

Tract‐by‐Tract Morphometric and Diffusivity Analyses In Vivo of Spinocerebellar Degeneration

Three-dimensional anisotropy contrast (3DAC) based on a periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) sequence on a 3.0 T system is a new magnetic resonance imaging technique capable of providing images with significantly high anatomical resolution. The purpose of this study was to confirm whether this technique can characterize the degenerative processes in the brainstem of patients with spinocerebellar degeneration (SCD). 3DAC images of 13 patients with multiple system atrophy with predominant cerebellar symptoms (MSA-C) and seven International Cooperative Ataxia Rating Scale (ICARS) score-matched patients with Machado-Joseph disease (MJD) were created using a diffusion-weighted PROPELLER sequence on a 3.0T system. The section of the middle pons was chosen for morphometric and diffusivity analyses. The above analyses showed that atrophy and increased diffusivity of the ventral portion of the pons indicated MSA-C, whereas atrophy and increased diffusivity of the pontine tegmentum indicated MJD. Furthermore, ICARS scores significantly correlated with both the severities of the pontine atrophy and the mean diffusivity values of the ventral pontocerebellar tracts. This study demonstrated that 3DAC PROPELLER on a 3.0T system enables in vivo "tract by tract" quantitative analysis of pontine degeneration in SCD.

Abnormal temporal difference reward-learning signals in major depression

Anhedonia is a core symptom of major depressive disorder (MDD), long thought to be associated with reduced dopaminergic function. However, most antidepressants do not act directly on the dopamine system and all antidepressants have a delayed full therapeutic effect. Recently, it has been proposed that antidepressants fail to alter dopamine function in antidepressant unresponsive MDD. There is compelling evidence that dopamine neurons code a specific phasic (short duration) reward-learning signal, described by temporal difference (TD) theory. There is no current evidence for other neurons coding a TD reward-learning signal, although such evidence may be found in time. The neuronal substrates of the TD signal were not explored in this study. Phasic signals are believed to have quite different properties to tonic (long duration) signals. No studies have investigated phasic reward-learning signals in MDD. Therefore, adults with MDD receiving long-term antidepressant medication, and comparison controls both unmedicated and acutely medicated with the antidepressant citalopram, were scanned using fMRI during a reward-learning task. Three hypotheses were tested: first, patients with MDD have blunted TD reward-learning signals; second, controls given an antidepressant acutely have blunted TD reward-learning signals; third, the extent of alteration in TD signals in major depression correlates with illness severity ratings. The results supported the hypotheses. Patients with MDD had significantly reduced reward-learning signals in many non-brainstem regions: ventral striatum (VS), rostral and dorsal anterior cingulate, retrosplenial cortex (RC), midbrain and hippocampus. However, the TD signal was increased in the brainstem of patients. As predicted, acute antidepressant administration to controls was associated with a blunted TD signal, and the brainstem TD signal was not increased by acute citalopram administration. In a number of regions, the magnitude of the abnormal signals in MDD correlated with illness severity ratings. The findings highlight the importance of phasic reward-learning signals, and are consistent with the hypothesis that antidepressants fail to normalize reward-learning function in antidepressant-unresponsive MDD. Whilst there is evidence that some antidepressants acutely suppress dopamine function, the long-term action of virtually all antidepressants is enhanced dopamine agonist responsiveness. This distinction might help to elucidate the delayed action of antidepressants. Finally, analogous to recent work in schizophrenia, the finding of abnormal phasic reward-learning signals in MDD implies that an integrated understanding of symptoms and treatment mechanisms is possible, spanning physiology, phenomenology and pharmacology.

SPINAL AND NUCLEUS CAUDALIS DORSAL ROOT ENTRY ZONE OPERATIONS FOR CHRONIC PAIN

Dorsal root entry zone (DREZ) operations came into medical practice after the demonstration of increased electrical activity in the dorsal horn of the spinal cord and brainstem in patients with deafferentation of the central nervous system after injury to these areas. The aim of the study was to describe the technique and the effectiveness of spinal DREZ and nucleus caudalis (NC) DREZ operations, which may be the treatments of choice in unique chronic pain conditions that do not respond to medical therapy or any other surgical methods. Fifty-five patients (44 spinal, 11 NC DREZ) underwent 59 (48 spinal, 11 NC DREZ) operations. There were 44 men and 11 women with a mean age of 46.4 years (range, 24-74 yr). The mean follow-up period was 72 months (range, 6 mo-20 yr). Follow-up assessments were performed with clinical examination on the first day and in the sixth and twelfth months postoperatively. Patients' pain scores and Karnofsky Performance Scale scores were also evaluated pre- and postoperatively. The initial success rates for spinal and NC DREZotomy procedures were 77 and 72.5%, respectively. In the spinal DREZotomy group, mortality occurred in one patient (2.2%). There were two cases of transient muscle weakness (4.4%) and two of cerebrospinal fluid fistulae (4.4%). In the NC DREZotomy group, mortality occurred in one patient (9%). There were two cases of transient ataxia (18%) and two of transient hemiparesis (18%). Spinal and trigeminal NC DREZ operations are effective in the treatment of intractable pain syndromes, especially in traumatic brachial plexus avulsions, segmental pain after spinal cord injury, postherpetic neuralgia, topographically limited cancer pain, and atypical facial pain.

Neuropathology of primary adult-onset dystonia

Idiopathic adult-onset primary dystonia usually affects the upper body and remains focal. Underlying mechanisms are unknown, and there are only limited neuropathologic studies in the literature. Recently, ubiquitinated perinuclear inclusion bodies were found in the brainstem of patients with DYT1-related dystonia. In X-linked recessive dystonia-parkinsonism, neuronal loss in the striosome compartment of the striatum has been described. However, it was unclear whether these changes are characteristic of these particular disorders or an epiphenomenon of dystonic conditions in general. Six cases of adult-onset dystonia and four controls were studied using immunohistochemistry to determine the presence of inclusion bodies immunoreactive for torsinA, ubiquitin, and laminA/C in the brainstem. The distribution of calcineurin expressing neurons in the striatum was also determined to ascertain whether there is loss of neurons in the striosome compartment. In contrast to early-onset dystonia, neuronal inclusions immunoreactive for torsinA, ubiquitin, and laminA/C were not present in the brainstem nuclei. There was no apparent loss of the striatal striosome compartment. Our findings suggest that the underlying mechanism in the adult-onset primary torsion dystonia is different from that of early-onset DYT1-related dystonia and also DYT3 X-linked recessive dystonia-parkinsonism. Alternative mechanisms may underpin the pathophysiology of adult-onset primary dystonia.

Evaluation of brainstem function in patients with spasmodic dysphonia using vestibular evoked myogenic potentials and auditory brainstem responses

Conclusion. The vestibular area is closer than the auditory region to nucleus ambiguus. If a ‘shared’ lesion involves regions of adjacent nuclei of the brainstem in patients with spasmodic dysphonia then vestibular area involvement is more possible than that of the auditory region. Objectives. The authors hypothesize that lower brainstem lesions and involvement of descending pathways of the spinal tract may be the site of lesion in patients with spasmodic dysphonia. Patients and methods. Ten patients with spasmodic dysphonia were tested using the auditory brainstem response (ABR) and vestibular evoked myogenic potentials (VEMPs). Results. No ABR abnormalities were found in right ears. Results of ABR on the left ear showed that one patient had abnormal ABR. This patient had severe sensorineural hearing loss on the left side. VEMPs displayed normal response in two patients bilaterally. First positive (p13) and second negative (n23) waves of VEMP could not be recorded in three cases unilaterally and in five patients bilaterally.

Pontine Hypoplasia in Children with Periventricular Leukomalacia

The brain stem in patients with periventricular leukomalacia (PVL) appears smaller than normal on MR imaging, but few reports have described this feature, and the number of patients has been relatively small. The present study was conducted to examine the hypothesis that the pons in patients with PVL is smaller than normal. Using MR imaging, we examined 80 children (43 boys and 37 girls) with PVL and 80 age-matched control children (41 boys and 39 girls). The control children were diagnosed as neurologically and developmentally normal by pediatric neurologists and also showed normal MR imaging findings. MR imaging was performed at a corrected age range of 0-5 years in both groups. We measured the anteroposterior diameter of the whole pons, the tegmentum and the basis, and the corpus callosal length by using midline T1-weighted sagittal images and compared each parameter between the PVL groups and the control groups. Pontine diameters in all of the regions were significantly smaller in the PVL group than in the control group (mean +/- SD, whole pontine diameters, 1.66 +/- 0.21 and 1.87 +/- 0.23 cm [P < .001]; basis diameters, 0.42 +/- 0.10 and 0.51 +/- 0.14 [P < .001]; tegmentum diameters, 1.23 +/- 0.20 and 1.36 +/- 0.19 [P < .001], respectively). The respective corpus callosal lengths were 5.02 +/- 0.90 and 5.51 +/- 0.76 (P < .001). There was no significant difference in the basis/tegmentum ratio between the PVL group and the control group. When the age-related pontine diameter differences were examined, there was already a significant difference at 0 years of age between the 2 groups. There was a significant correlation between whole pontine diameter and corpus callosal length in the PVL group (correlation coefficient, 0.52; P < .001) and the control group (correlation coefficient, 0.63; P < .001). We have proven that pontine diameter in patients with PVL is significantly smaller than that in normal control subjects, including each diameter of basis and tegmentum.

Acute Levodopa Intake and Associated Cortisol Decrease in Patients With Parkinson Disease

Levodopa application improves motor symptoms in patients with Parkinson disease (PD). Levodopa induces lower cortisol plasma levels and decreases serotonergic activity in certain brain areas of fish. The objectives of this study were to perform repeat cortisol concentration measurements before and after the administration of soluble levodopa/benserazide (dose, 200 mg) in 32 patients with PD during an interval of 150 minutes. The cortisol concentrations significantly decreased after levodopa intake, particularly in the patients with more advanced stage of PD, but not in the less affected patients. There were significantly lower cortisol levels in the patients at the advanced stage of PD compared with those of the earlier patients with PD, particularly at -30, 0, and 90 minutes before/after levodopa application. Significant inverse relations were found between the cortisol levels and the Unified Parkinson Disease Rating Scale total score, particularly at 60 and 90 minutes after levodopa intake. Neurodegeneration occurs in striatal regions and in the brain stem of patients with PD. The 5-HT-containing neuronal terminals of the brain stem hypothetically mediate the cortisol level decrease after levodopa intake because these cells contain an important fraction of amino acid decarboxylase. Therefore, this compartment may be the site of enzymatic conversion of superfluous, exogenous levodopa to dopamine. Consequently, short-term levodopa administration also leads to levodopa uptake in these 5-HT-metabolizing neurons, which interferes with the 5-HT synthesis and may cause a decrease of 5-HT levels. These lower 5-HT levels reduce the hypothalamic function and, via the corticotropin axis, the subsequent peripheral cortisol release. Thus, levodopa-induced cortisol decrease may be related to PD progression.

Resection of the Odontoid Process through the Expanded Endonasal Approach: Clinical Experience from 14 Patients

Background: Indications for removal of the odontoid process include decompression of the brainstem in patients with rheumatoid degeneration and access to tumors or vascular lesions at the foramen magnum. Resection of the odontoid can be accomplished using a completely transnasal endoscopic approach.

Clinical Indications and Experience with the Expanded Endonasal Approach for Resection of the Odontoid Process

Purpose: Indications for removal of the odontoid process include decompression of the brainstem in patients with rheumatoid degeneration and access to tumors at the foramen magnum. Resection of the odontoid process can be accomplished using a completely transnasal endoscopic approach. Methods: Retrospective review of patients undergoing transnasal endoscopic resection of the odontoid to assess preoperative characteristics and postoperative complications and outcomes. Patients were followed for a minimum of 3 months in the postoperative period, and/or until death. In addition to the primary procedure, those patients with preoperative cervical instability underwent posterior fusion of the upper cervical spine to the occiput for stabilization during the same hospitalization. Results: Seven patients underwent transnasal endoscopic resection of the odontoid process for rheumatoid pannus and brainstem compression. Six patients had a transodontoid approach for resection of primary or metastatic neoplasms to the region of the skull base. One patient presented with an aneurysm of the right vertebrobasilar artery causing brainstem compression. Perioperatively, four patients required a tracheostomy; three of them had significant preoperative pharyngeal and/or respiratory dysfunction. Four patients had reparable cerebrospinal fluid leaks, and there were no infectious complications. There was one death in the rheumatoid arthritis group due to a pulmonary embolus. Deaths in the tumor-bearing groups were due to (1) ARDS and incidental finding of an obstructing pulmonary mass, and (2) status epilecticus associated with HIV-positive meningitis following excision of a posterior fossa intraparenchymal lesion. Otherwise, most patients demonstrated an improvement of their preoperative neurologic symptoms. No patients developed symptoms of prolonged palatal dysfunction. Conclusions: This early series demonstrates the feasibility of a fully endoscopic, completely transnasal approach for the resection of the odontoid process. Potential advantages include improved visualization, limited morbidity, decreased pain, and faster recovery than traditional approaches.