Upper Airway Stimulation in Patients with Obstructive Sleep Apnea: Long-Term Surgical Success, Respiratory Outcomes, and Patient Experience

Abstract Introduction Upper airway stimulation (UAS) with electric activation of the hypo-glossal nerve has emerged as a promising treatment for patients with moderate-to-severe obstructive sleep apnea. Objective To retrospectively analyze objective and subjective outcome measures after long-term follow-up in obstructive sleep apnea patients receiving upper airway stimulation. Methods An observational retrospective single-center cohort study including a consecutive series of patients diagnosed with obstructive sleep apnea receiving upper airway stimulation. Results Twenty-five patients were included. The total median apnea-hypopnea index (AHI) significantly decreased from 37.4 to 8.7 events per hour at the 12-month follow-up (p < 0.001). The surgical success rate was 96%. Adverse events were reported by 28% of the patients. Conclusion Upper airway stimulation is an effective and safe treatment for obstructive sleep apnea in patients with continuous positive airway pressure (CPAP) failure or intolerance. However, it is possible that the existing in and exclusion criteria for UAS therapy in the Netherlands have positively influenced our results.

Microanatomic analyses of extratemporal facial nerve and its branches, hypoglossal nerve, sural nerve, and great auricular nerve

Abstract Objective: To investigate microanatomic organizations of the extratemporal facial nerve and its branches, hypoglossal nerve, sural nerve, and great auricular nerve. Methods: Nerve samples were dissected in 12 postmortem autopsies, and histomorphometric analyses were conducted. Results: There was no significant difference between the right and left sides of the nerve samples for the nerve area, fascicle area, number of fascicles and average number of axons. The lowest mean fascicle number was found in the hypoglossal nerve (4.9 ± 1.4) while the highest was in great auricular nerve (11.4 ± 6.8). The highest nerve area (3,182,788 ± 838,430 μm2), fascicle area (1,573,181 ± 457,331 μm2) and axon number (14,772 ± 4402) were in hypoglossal nerve (p < 0.05). The number of axons per unit nerve area was higher in the facial nerve, truncus temporofacialis, truncus cervicofacialis and hypoglossal nerve, which are motor nerves, compared to the sural nerve and great auricular nerve, which are sensory nerves (p < 0.05). The number of axons per unit fascicle area was also higher in motor nerves than in sensory nerves (p < 0.05). Conclusion: In the present study, it was observed that each nerve contained a different number of fascicles and these fascicles were different both in size and in the number of axons they contained. All these variables could be the reason why the desired outcomes cannot always be achieved in nerve reconstruction.

Landmarks for the hypoglossal nerve within the anterior cervical triangle / Topografía del nervio hipogloso en el triángulo cervical anterior

SUMMARY: Cranial nerve injury is one of the neurologic complications following carotid endarterectomy. The hypoglossal nerve is one of the most frequently injured nerves during carotid endarterectomy. Guidelines suggest that proper anatomic knowledge is crucial to avoid cranial nerve injury. The aim of the present study is to provide landmarks for the localization of the hypoglossal nerve during carotid endarterectomy. 33 anterior cervical triangles of formalin-fixed adult cadavers were dissected. The "carotid axis" was defined and measured, the level of the carotid bifurcation within the carotid axis was registered. "High carotid bifurcation" was considered for those carotid bifurcation found in the upper 25 mm of the carotid axis. The distance between the hypoglossal nerve and the carotid bifurcation was measured (length 1). The relationship between the hypoglossal nerve and the posterior belly of the digastric muscle was registered. For caudal positions, the distance between hypoglossal nerve and posterior belly of the digastric muscle was determined (length 2). Carotid axis range 88.3 mm-155.4 mm, average 125.8 mm. Level of the carotid bifurcation within the carotid axis range 75.3 mm-126.5 mm, mean 102.5 mm. High carotid bifurcation was found in 19 cases (57 %). Length 1 ranged from 1.6 mm to 38.1, mean 17.5. Finally, in 29 specimens (87.8 %) the hypoglossal nerve was caudal to posterior belly of the digastric muscle, whereas in 4 cases (12.2 %) it was posterior. Length 2 ranged from 1 mm to 17.0 mm, mean 6.9 mm. Distances between the hypoglossal nerve and nearby structures were determined. These findings may aid the surgeon in identifying the hypoglossal nerve during carotid endarterectomy and thus prevent its injury.

RESUMEN: La lesión de pares craneales es una de las complicaciones neurológicas posteriores a la endarterectomía carotídea. El nervio hipogloso es uno de los nervios lesionados más frecuentemente durante la endarterectomía carotídea. Las guías de actuación clínica sugieren que el conocimiento anatómico adecuado es crucial para evitar lesiones de los nervios craneales. El objetivo del presente estudio fue proporcionar puntos de referencia para la ubicación del nervio hipogloso durante la endarterectomía carotídea. Se disecaron 33 triángulos cervicales anteriores de cadáveres adultos fijados en solución a base de formaldehído. Se definió y midió el "eje carotídeo", se registró el nivel de la bifurcación carotídea dentro del eje carotídeo. Se consideró una "bifurcación carotídea alta" para aquellas bifurcaciones carotídeas encontradas en los 25 mm superiores del eje carotídeo. Se midió la distancia entre el nervio hipogloso y la bifurcación carotídea (longitud 1). Se registró la relación entre el nervio hipogloso y el vientre posterior del músculo digástrico. Para las posiciones caudales, se determinó la distancia entre el nervio hipogloso y el vientre posterior del músculo digástrico (longitud 2). Rango del eje carotídeo 88,3 mm-155,4 mm, media 125,8 mm. Rango del nivel de la bifurcación carotídea dentro del eje carotídeo 75,3 mm-126,5 mm, media 102,5 mm. Se encontró una bifurcación carotídea alta en 19 casos (57 %). La longitud 1 osciló entre 1,6 mm y 38,1, con una media de 17,5. Finalmente, en 29 muestras (87,8 %) el nervio hipogloso fue caudal al vientre posterior del músculo digástrico, mientras que en 4 casos (12,2 %) fue posterior. La longitud 2 osciló entre 1 mm y 17,0 mm, con una media de 6,9 mm. Se determinaron las distancias entre el nervio hipogloso y las estructuras cercanas. Estos hallazgos pueden ayudar al cirujano a identificar el nervio hipogloso durante la endarterectomía carotídea y así prevenir su lesión.

Hypoglossal-Facial Anastomosis for Facial Nerve Reconstruction: Outcomes using the Side-to-End Surgical Technique

Introduction The side-to-end hypoglossal-facial anastomosis (HFA) technique is an excellent alternative technique to the classic end-terminal anastomosis, because itmay decrease the symptoms resulting from hypoglossal-nerve transection. Methods Patients with facial nerve palsy (House-Brackmann [HB] grade VI) requiring facial reconstruction from 2014 to 2017were retrospectively included in the study. Results In total, 12 cases were identified, with a mean follow-up of 3 years. The causes of facial paralysis were due to resection of posterior-fossa tumors and trauma. There was improvement in 91.6% of the patients (11/12) after the HFA. The rate of improvement according to the HB grade was as follows: HB III - 58.3%; HB IV - 16.6%; and HB II - 16.6%. The first signs of improvement were observed in the patients with the shortest time between the paralysis and the anastomosis surgery (3.5months versus 8.5 months; p » 0.011). The patients with HB II and III had a shorter time between the diagnosis and the anastomosis surgery (mean: 5.22 months), while the patients with HB IV and VI had a longer time of paresis (mean: 9.5 months; p » 0.099). We did not observe lingual atrophy or changes in swallowing. Discussion and Conclusion Hypoglossal-facial anastomosis with the terminolateral technique has good results and low morbidity in relation to tongue motility and swallowing problems. The HB grade and recovery appear to be better in patients operated on with a shorter paralysis time.

Endovascular management of dissecting posterior cerebral artery aneurysm associated with persistent hypoglossal artery: A case report / Tratamento endovascular do aneurisma dissecante da artéria cerebral posterior associado à artéria hipoglossa persistente: relato de caso

Abstract Persistent embryological connections between the anterior and posterior circulations are rare entities. Persistent hypoglossal artery is the second most common persistent carotid-basilar anastomosis. As it is often associated with hypoplasia of vertebral arteries, it poses a challenge during endovascular interventions. We present a case of a 32-year-old woman who presented with occipital headache of four weeks' duration. Magnetic Resonance Angiography showed hypoplastic vertebral arteries with a persistent hypoglossal artery arising from the cervical segment of the left internal carotid artery and supplying the entire posterior circulation, associated with a dissecting aneurysm of the right posterior cerebral artery. Endovascular parent vessel occlusion was performed for the dissecting posterior cerebral artery aneurysm by navigating the guide catheter, microwire, and microcatheter through the persistent hypoglossal artery because the vertebral arteries were hypoplastic. Post-intervention, the patient did not develop any neurological deficit and was discharged in a stable condition.

Resumo Conexões embriológicas persistentes entre as circulações anterior e posterior são entidades raras. A artéria hipoglossa persistente é a segunda anastomose carotídeo-basilar persistente mais comum. Como está frequentemente associada à hipoplasia das artérias vertebrais, apresenta um desafio durante as intervenções endovasculares. Apresentamos o caso de uma mulher de 32 anos que apresentou cefaleia occipital com duração de quatro semanas. A angiografia por ressonância magnética mostrou artérias vertebrais hipoplásicas com artéria hipoglossa persistente surgindo do segmento cervical da artéria carótida interna esquerda e suprindo toda a circulação posterior com um aneurisma dissecante da artéria cerebral posterior direita. A oclusão endovascular do vaso parental foi realizada para o aneurisma da dissecção da artéria cerebral posterior pela passagem de cateter guia, microfio e microcateter pela artéria hipoglossa persistente, pois as artérias vertebrais eram hipoplásicas. Após a intervenção, a paciente não apresentou déficit neurológico e recebeu alta em uma condição estável.

Síndrome de Tapia posterior a cirugía nasal

Resumen El síndrome de Tapia es una complicación poco frecuente secundaria a la manipulación de la vía aérea. Se caracteriza por haber una lesión concomitante de los pareas craneales X (nervio vago) y XII (nervio hipogloso), usualmente por compresión o sobredistensión de estos. Inicialmente puede hacernos sospechar una lesión central, al haber compromiso de dos nervios craneales bajos en forma simultánea, pero la gran mayoría de los casos descritos son lesiones periféricas. De los procedimientos asociados a esta complicación, los que lideran en frecuencia son los de cabeza y cuello, por lo que es de gran importancia tenerlo en conocimiento en el desarrollo de nuestra práctica clínica. Nuestro paciente presentó esta complicación tras una septoplastía con turbinectomía sin complicaciones en el sitio operatorio, ni anestésicas. Se manejó con fonoaudiología y corticoides orales, con recuperación completa a los cuatro meses de posoperatorio.

Abstract Tapia's Syndrome is a rare complication secondary to airway manipulation. It is characterized by a concurrent lesion of cranial nerve pairs X (vagus nerve) and XII (hypoglossal nerve), usually attributed to compression or stretching of these nerves. Initially, it may lead us to suspect a central lesion, as there is simultaneous involvement of two low cranial nerves, but the vast majority of cases described are peripheral lesions. The procedures most frequently associated with this complication are head and neck surgery, which is why it is very important to bear this in mind in the development of our clinical practice. Our patient showed Tapia's syndrome following septoplasty with turbinectomy without complications in the operative site nor under anesthesia. He was treated with phoniatric and oral corticoids, recovering completely four months after surgery.

Morphometric Study of Hypoglossal and Facial Nerves and its Significance in Hypoglossal-Facial Nerve Anastomosis.

Background: During the repairing of facial nerve injurymost common nerve used is the hypoglossal nerve. Aimand Objectives: To measure the distance between theanatomical landmarks, facial nerve and hypoglossalnerve which will be beneficial to locate the facial nerveand hypoglossal nerve more effortlessly and willdecrease the hazard of procedural problems. Materialand Methods: Thirty specimens were dissected.Measurements of the hypoglossal and facial nerveswere taken from various anatomical landmarks. Datawere analyzed using Statistical Package for SocialSciences 16 version. Results: The mean distance of theorigin of the facial nerve to the angle of mandible wascm, the mean distance of the origin of thefacial nerve to the tip of mastoid process wascm, the mean distance of common carotidbifurcation to the hypoglossal nerve where it crossesthe external carotid artery was cm, the meandistance of common carotid bifurcation to thehypoglossal nerve where it crosses the internal carotidartery was cm and the mean distance ofhypoglossal nerve to the tip of mastoid process wascm. Conclusion: The results of this studywill help and prevent any complication in identifyingthe hypoglossal nerve and facial nerve duringhypoglossal-facial nerve anastomosis.

Whole-Brain Monosynaptic Inputs to Hypoglossal Motor Neurons in Mice / 神经科学通报·英文版

Hypoglossal motor neurons (HMNs) innervate tongue muscles and play key roles in a variety of physiological functions, including swallowing, mastication, suckling, vocalization, and respiration. Dysfunction of HMNs is associated with several diseases, such as obstructive sleep apnea (OSA) and sudden infant death syndrome. OSA is a serious breathing disorder associated with the activity of HMNs during different sleep-wake states. Identifying the neural mechanisms by which the state-dependent activities of HMNs are controlled may be helpful in providing a theoretical basis for effective therapy for OSA. However, the presynaptic partners governing the activity of HMNs remain to be elucidated. In the present study, we used a cell-type-specific retrograde tracing system based on a modified rabies virus along with a Cre/loxP gene-expression strategy to map the whole-brain monosynaptic inputs to HMNs in mice. We identified 53 nuclei targeting HMNs from six brain regions: the amygdala, hypothalamus, midbrain, pons, medulla, and cerebellum. We discovered that GABAergic neurons in the central amygdaloid nucleus, as well as calretinin neurons in the parasubthalamic nucleus, sent monosynaptic projections to HMNs. In addition, HMNs received direct inputs from several regions associated with respiration, such as the pre-Botzinger complex, parabrachial nucleus, nucleus of the solitary tract, and hypothalamus. Some regions engaged in sleep-wake regulation (the parafacial zone, parabrachial nucleus, ventral medulla, sublaterodorsal tegmental nucleus, dorsal raphe nucleus, periaqueductal gray, and hypothalamus) also provided primary inputs to HMNs. These results contribute to further elucidating the neural circuits underlying disorders caused by the dysfunction of HMNs.

Neurofibroma del asa del hipogloso: reporte de caso / Neurofibroma from the Ansa Hypoglossi: Case report

Los neurofibromas son tumores benignos con origen en la vaina de nervios periféricos; aunque raros, son diagnosticados en pacientes sin historia previa de neurofibromatosis tipo 1, en cuyo caso se constituye en una forma esporádica. Se presenta el caso de un paciente masculino de 27 años con una masa supraclavicular izquierda asintomática de crecimiento progresivo. En la intervención se encontró que la masa tenía origen en el asa del hipogloso.

Neurofibromas are benign tumors that originate from the sheet of peripheral nerves; even though rare, they are occasionally seen in patients with a prior history of neurofibromatosis type1, in which case a sporadic form is diagnosed. A 27-year-old male is described with a left asymptomatic supraclavicular slow growing mass, different of the suspected vagus nerve tumor. In surgery, it was found that the tumor was originating from the Ansa Hypoglossi.

Variations, relations and clinical significance of carotid arterial system in anterior neck: a cadaveric study

Background: The common carotid, internal and external carotid arteries and their branches serve as major source of blood supply in head-neck region of human and are often encountered during numerous surgical and clinical interventions of neck.Methods: We dissected and examined both sides of neck in 49 well embalmed cadavers (98 sides). We recorded the following anatomical parameters of carotid arterial system-level of bifurcation, the relation between internal and external carotid arteries, branching pattern of anterior branches of external carotid artery, tortuosity in carotid arterial system, and relation of hypoglossal nerve with the carotid arteries.Results: In 56.16 % cases, the common carotid arterial bifurcation took place at the upper border of thyroid cartilage though high bifurcation was quite common (43.88%). The external carotid artery was located antero-medial to internal carotid artery in most cases (93.87%). Abnormal tortuosity of carotid arterial system was detected in 2.04% cases only. In 86.73% cases, the hypoglossal nerve crossed the internal and external carotid artery superior to carotid bifurcation above the level of hyoid bone while in 1 case it crossed immediately inferior to carotid bifurcation. In branching pattern, following variations were observed- linguo-facial trunk in 15.3% cases, thyro-lingual trunk in 5.1% cases, origin of superior thyroid artery from common carotid in 10.02% cases and origin of superior thyroid from internal carotid in one case (1.02%).Conclusions: The carotid arterial system has complex and variable anatomy in neck and this information should be kept in mind to avoid unwanted damage during surgical procedures of neck.

Morphometric Analysis Of The Occipital Condyles And Their Correlation With Hypoglossal Canal In Dry Skulls Of South Indians

Background: Morphometric analysis of the occipital condyles is essential for craniovertebral junction surgeries.There are no studies done yet on correlation of hypoglossal canal and occipital condyle, therefore the presentstudy is carried out to find differences of parameters of OC in different races and to find out the correlation ofvarious parameters of occipital condyle with orifices of hypoglossal canal.Method: The size, shape and anterior, posterior inter condylar distances of occipital condyles and the locationsof the extracranial and intracranial orifices of the 108 hypoglossal canal were studied in 55 dry skulls.Result: The Mean length, height, width were 21.64±2.97, 11.06±2.2, 6.15±1.44 respectively.Anterior, posteriorinter condylar distances mean were ranged between 13.30-32.93 and 21.46– 46.77 respectively and most commonshape of occipital condyles was oval. Location of hypoglossal canal extra cranially was 3,whereas intra craniallyit was 4 for both right and left sides. There was strong correlation between length of occipital condyle and widthbut the same was not with location of hypoglossal canal.Conclusion: The measurements of occipital condyles were found to have some similarities and some dissimilariesamong different races. These differences could be useful for anthropometric analysis and forensic sciencesstudies. Significant correlation was found between length and width, width and height, height and length.However no correlation could be found between various parameters of occipital condyle and orifices of hypoglossalcanal.

Ansa cervicalis: a comprehensive review of its anatomy, variations, pathology, and surgical applications / 대한해부학회지

The ansa cervicalis is a neural loop in the neck formed by connecting the superior root from the cervical spinal nerves (C1–2) and the inferior root descending from C2–C3. It has various anatomical variations and can be an important acknowledgment in specific operations of the neck region. This is a review the anatomy, variations, pathology and clinical applications of the ansa cervicalis.

Application of hypoglossal microcirculation imaging system in observation of distal microcirculation after myocardial infarction / 解放军医学杂志

[Abstract] Objective To explore the feasibility of detecting cardiac microvessel with hypoglossal microcirculatory imaging system (abbreviated as microvision system), and explore its clinical value in diagnosis, treatment and prognosis evaluation of coronary microcirculation disorder. Methods Normal SD rats were used as research objects to detect the microcirculation of the main coronary artery and its branches with microvision system. Forty SD rats were randomly divided into two groups (20 each): myocardial infarction (MI) group and sham operation (Sham) group. The left anterior descending branch of coronary artery was ligated to make the model of myocardial infarction in MI group, and the sham group received the same treatment as in MI group but no ligation. The microvessel of left anterior descending branch was detected and analyzed in sham group and MI group before operation and 5, 10 and 20 minutes after operation by microvision system. The measured parameters included the total vessel density (TVD), the perfused vessel density (PVD), the proportion of perfused vessels (PPV), the microcirculatory flow index (MFI) and the heterogeneity index (HI). Results In microvision system, the left and right coronary vessels and their branches in the normal rat heart were clearly visible, the blood flow perfusion was continuous, and the blood vessels were dense and evenly distributed. In MI group, the longer the ligation time, the more blurred the vein of the microvessel. Furthermore, the blood flow was interrupted and the vessels were non-uniform distribution. The microcirculation was invisible and blood flow disappeared at 20min time point after infarction. Compared with that at 5min time point, TVD, PVD, PPV and MFI decreased, while HI increased at 10min and 20min time points (P<0.05). Compared with that in sham group, TVD, PVD, PPV and MFI decreased, while HI increased in MI group (P<0.05). Conclusion The microvision system can be used to detect cardiac microcirculation in normal and pathological conditions of rats.

Unilateral hypoglossal nerve palsy after the use of laryngeal mask airway (LMA) Protector: a case report / 대한마취과학회지

BACKGROUND: The laryngeal mask airway (LMAⓇ) Protector™ (Teleflex Medical Co., Ireland) is the latest innovation in the second generation of LMA devices. One distinguishing feature of this device is its integrated, color-coded cuff pressure indicator (Cuff ™ technology) which enables continuous cuff pressure monitoring and allows adjustments when necessary; this ensures patient safety due to better monitoring.CASE: We report a case of postoperative unilateral hypoglossal nerve palsy after uncomplicated use of the LMA Protector. To the best of our knowledge, this could be the second reported case.CONCLUSIONS: This case demonstrates that anesthetists need to routinely measure cuff pressure and that the Cuff Pilot™ technology is not a panacea for potential cranial nerve injury after airway manipulation.

Neurofibroma del hipogloso en un niño colombiano. Reporte de caso / Hypoglossal neurofibroma in a Colombian child: case report

Resumen Se presenta el caso de un paciente masculino de 14 años de edad, con antecedente de dos intervenciones quirúrgicas debidas a la presencia de una masa a nivel sublingual -la primera a los 8 meses de edad y la segunda a los 13 años- y sin información de estudios histopatológicos. Cerca de 8 meses después de la última intervención quirúrgica es valorado por el Servicio de Cirugía Maxilofacial de la Fundación Hospital Pediátrico de La Misericordia en Bogotá D.C., Colombia, por crecimiento acelerado de la misma lesión y por problemas en la deglución y el lenguaje. En la revisión del paciente se encuentra una masa importante sublingual, dificultad en el lenguaje, deformidad mandibular y alteraciones en la mordida, por lo que se decide intervenir quirúrgicamente de nuevo. El resultado de la biopsia es un tumor mesenquimal benigno característico de neurofibroma, que por su ubicación sugiere probable compromiso del nervio hipogloso.

Abstract This article presents the case of a 14-year-old male patient, with a history of two surgical procedures due to the presence of a mass at sublingual level -the first performed at the age of 8 months and the second at 13 the age of years- and without information of histopathological studies. About 8 months after the last surgical procedure, the patient was assessed by the Maxillofacial Surgery Service of the Fundación Hospital Pediátrico de La Misericordia, in Bogotá D.C. - Colombia, due to the rapid growth of the same lesion and swallowing and language disorders. On physical examination, a significant sublingual mass, difficulty in language, mandibular deformity and malocclusion were observed, so a new surgical intervention was indicated. The result of the biopsy revealed a benign mesenchymal tumor, typically seen in neurofibroma, which suggested a possible involvement of the hypoglossal nerve due to its location.

Unilateral Hypoglossal Neuropathy in Multifocal Acquired Demyelinating Sensory and Motor Neuropathy: Differential Diagnosis of Motor Neuron Disease

Multifocal acquired demyelinating sensory and motor neuropathy (MADSAM) is a peripheral neuropathy characterized by multifocal weakness and associated sensory impairment. MADSAM is associated with multifocal persistent conduction block and other signs of demyelination. The incidence of cranial nerve involvement in MADSAM was recently reported to be approximately 15%. However, reports of hypoglossal neuropathy occurring in MADSAM are rare. Unilateral hypoglossal neuropathy in MADSAM is usually misdiagnosed as motor neuron disease. We report a patient with MADSAM presenting with tongue hemiatrophy.

Diagnosis of variants of carotid-vertebasilar anastomoses on MR angiography / 中华放射学杂志

Objective To explore the feature of embryonic communication between the carotid and vertebro-basilar system using MRA of head and neck on MR. Methods The MRA images from 7 246 consecutive patients in Liaocheng People's hospital between June 2009 and December 2015 were retrospectively reviewed. The feature of embryonic communication between internal carotid, external carotid artery and vertebro-basilar system using MRA was analyzed by two doctors. Results Forty-four cases of embryonic communication between the carotid and vertebro-basilar system were found. Thirty-nine cases of primitive trigeminal artery (PTA) and primitive trigeminal artery variants (PTAV) were detected by MRA. The prevalence of both PTA and PTAV was 0.54% (PTA, 27 cases;PTAV, 12 cases). Twenty-three cases of PTA were lateral types;four cases were medial types. All PTA originated from C4 portion of internal carotid artery, of which 27 cases connected with the basilar artery and two cases connected with the superior cerebellar artery. The region of the BA proximal to the site of convergence with the PTA was hypoplastic in seven cases and completely absent in two cases. Three cases of primitive hypoglossal artery and 2 cases of primitive proatlantal artery were detected by MRA. The prevalence of primitive hypoglossal artery and primitive proatlantal artery was 0.04% and 0.03 % respectively. Two cases of primitive hypoglossal artery were from the lateral internal carotid artery and one was from the external carotid artery. It's all on the right side. One case of primitive proatlantal artery was on the left which arises from the external carotid artery, one on the right which originated from the outer part of the internal carotid artery. Thirty-four cases were coexisted with other variants of head and neck vessels. All of the primitive hypoglossal arteries were coexisted with vertebral artery absence. One case of primitive proatlantal intersegmental artery was coexisted with vertebral artery dysplasia. Eighteen cases were associated with cerebral infarctions, and three cases with aneurysm. Conclusions MRA can accurately assess the variants of carotid-vertebasilar anastomoses and have diagnostic significance.

Intraoperative Monitoring of Hypoglossal Nerve Using Hypoglossal Motor Evoked Potential in Infratentorial Tumor Surgery: A Report of Two Cases

The hypoglossal nerve (CN XII) may be placed at risk during posterior fossa surgeries. The use of intraoperative monitoring (IOM), including the utilization of spontaneous and triggered electromyography (EMG), from tongue muscles innervated by CN XII has been used to reduce these risks. However, there were few reports regarding the intraoperative transcranial motor evoked potential (MEP) of hypoglossal nerve from the tongue muscles. For this reason, we report here two cases of intraoperative hypoglossal MEP monitoring in brain surgery as an indicator of hypoglossal deficits. Although the amplitude of the MEP was reduced in both patients, only in the case 1 whose MEP was disappeared demonstrated the neurological deficits of the hypoglossal nerve. Therefore, the disappearance of the hypoglossal MEP recorded from the tongue, could be considered a predictor of the postoperative hypoglossal nerve deficits.

An Experimental Study on the Optimal Timing for the Repair of Incomplete Facial Paralysis by Hypoglossal-facial 'Side'-to-side Neurorrhaphy in Rats / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the optimal timing for the repair of persistent incomplete facial paralysis by hypoglossal-facial 'side'-to-side neurorrhaphy in rats.</p><p><b>METHODS</b>A total of 30 adult rats with crushed and bulldog-clamped facial nerve injury were randomly divided into 5 groups (n = 6 each) that were subjected to injury without nerve repair or with immediate repair, 2-week-delayed repair, 4-week-delayed repair, or 8-week-delayed repair. Three months later, the effects of repair in each rat were evaluated by facial symmetry assessment, electrophysiological examination, retrograde labeling, and axon regeneration measurement.</p><p><b>RESULTS</b>At 3 months after injury, the alpha angle significantly increased in the group of rats with 4-week-delayed repair compared with the other four groups. Upon stimulation of the facial nerve or Pre degenerated nerve, the muscle action potentials MAPs were recorded in the whisker pad muscle, and the MAP amplitude and area under the curve in the 4-week-delayed repair group were significantly augmented at 3 months post-injury. Similarly, the number of retrograde-labeled motor neurons in the facial and hypoglossal nuclei was quantified to be significantly greater in the 4-week-delayed repair group than in the other groups, and a large number of regenerated axons was also observed.</p><p><b>CONCLUSION</b>The results of this study demonstrated that hemiHN-FN neurorrhaphy performed 4 weeks after facial nerve injury was most effective in terms of the functional recovery of axonal regeneration and activation of facial muscles.</p>

Fisiopatología del síndrome de apnea-hipopnea obstructiva del sueño (SAHOS) / Pathophysiology of obstructive sleep apnea-hypopnea syndrome (OSAHS)

Resumen El síndrome de apnea-hipopnea obstructiva del sueño (SAHOS) es una enfermedad caracterizada por la obstrucción recurrente de la vía aérea superior (VAS), con disminución en el flujo de aire, hipoxemia intermitente y despertares durante el sueño. En la fisiopatología del SAHOS se presentan dos factores esenciales: las alteraciones anatómicas y la disminución o ausencia del control neural. Durante el estudio del SAHOS se debe identificar el sitio o sitios de obstrucción de la VAS, que pueden ir desde las alas nasales hasta la hipofaringe. Otro factor importante en este síndrome es el influjo nervioso en el tono muscular de la hipofaringe, así como los cambios en el pH sanguíneo y secundarios a los microdespertares. La posición corporal y el estadio de sueño son factores determinantes de la severidad. La fisiopatología del SAHOS debe ser entendida para poder estudiar de forma adecuada a un paciente y darle la mejor opción de tratamiento.

Abstract Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a disease characterized by recurrent upper airway obstruction (UAO), with decreased airflow, intermittent hypoxemia, and awakening during sleep. Two essential factors are related to the pathophysiology of OSAHS: anatomical alterations and reduction or absence of neural control. While studying OSAHS, the site or sites of obstruction of the UA should be identified; they may extend from the nasal wings to the hypopharynx. Another important factor in this syndrome is the nervous influence on muscle tone of the hypopharynx, as well as the changes in blood pH, which are secondary to micro-arousals. Body position and sleep stage determine the severity. The pathophysiology of OSAHS should be understood to properly study a patient and provide the best treatment option.