The laryngopharyngeal nerve: a comprehensive review / 대한해부학회지

The laryngopharyngeal nerve has received much less attention that the other contributions to the pharyngeal plexus i.e., glossopharyngeal and vagus nerves. Often, in descriptions and depictions, the nerve is simply labeled as the sympathetic contribution to the pharyngeal plexus. As there is such scant information available regarding this nerve, the present review was performed. Very little is found in the extant medical literature regarding the laryngopharyngeal nerve. However, based on available data, the nerve is a consistent contributory to the pharyngeal plexus and serves other adjacent areas e.g., carotid body. Therefore, a better understanding of this structure’s anatomy is important for those who operate in this area. Further studies are necessary to better elucidate the true function of the laryngopharyngeal nerve.

Innervation of pineal gland by the nervus conarii: a review of this almost forgotten structure / 대한해부학회지

The nervus conarii provides sympathetic nerve innervation to the pineal gland, which is thought to be the primary type of stimulus to this gland. This underreported nerve has been mostly studied in animals. One function of the nervus conarii may be to activate pinealocytes to produce melatonin. Others have also found substance P and calcitonin gene-related peptide from the nervus conarii ending in the pineal gland. The following paper reviews the extant medical literature on the nervus conarii including its anatomy and potential function.

An unusual arrangement between the highest denticulate ligament and posterior inferior cerebellar artery / 대한해부학회지

The posterior inferior cerebellar artery (PICA) is often involved in pathologies of the posterior cranial fossa. Therefore, a good understanding of the vessel’s normal and variant courses is important to the neurosurgeon or neurointerventionalist. During the routine microdissection of the craniocervical junction, an unusual arrangement between the highest denticulate ligament and PICA was observed. On the right side, the PICA was given rise to by the V4 segment of the vertebral artery 9 mm after the artery entered the dura mater of the posterior cranial fossa. The artery made an acute turn around the lateral edge of the highest denticulate ligament to then recur 180 degrees and travel medially toward the brainstem. Invasive procedures that target the PICA should be aware of the variant as described herein.

The first report of the buckled thyroid cartilage in a human cadaver / 대한해부학회지

We present the first case of buckled thyroid cartilage identified in a human cadaver. This rare anatomical variant, in patients, often produces dysphonia and is a potential source for diagnostic confusion. In the cadaveric case described, the laryngeal prominence is deviated to the left without deviation of the internal structures of the larynx, such as vocal folds and vocalis muscles. The medical history of the patient is not known. Finally, a review of current literature on the buckled thyroid cartilage is presented. Such a case represents a rare opportunity to visualize this deformity via anatomical dissection.

Activation of PXR causes drug interactions with Paxlovid in transgenic mice

Paxlovid is a nirmatrelvir (NMV) and ritonavir (RTV) co-packaged medication used for the treatment of coronavirus disease 2019 (COVID-19). The active component of Paxlovid is NMV and RTV is a pharmacokinetic booster. Our work aimed to investigate the drug/herb-drug interactions associated with Paxlovid and provide mechanism-based guidance for the clinical use of Paxlovid. By using recombinant human cytochrome P450s (CYPs), we confirmed that CYP3A4 and 3A5 are the major enzymes responsible for NMV metabolism. The role of CYP3A in Paxlovid metabolism were further verified in Cyp3a-null mice, which showed that the deficiency of CYP3A significantly suppressed the metabolism of NMV and RTV. Pregnane X receptor (PXR) is a ligand-dependent transcription factor that upregulates CYP3A4/5 expression. We next explored the impact of drug- and herb-mediated PXR activation on Paxlovid metabolism in a transgenic mouse model expressing human PXR and CYP3A4/5. We found that PXR activation increased CYP3A4/5 expression, accelerated NMV metabolism, and reduced the systemic exposure of NMV. In summary, our work demonstrated that PXR activation can cause drug interactions with Paxlovid, suggesting that PXR-activating drugs and herbs should be used cautiously in COVID-19 patients receiving Paxlovid.

The function of the tensor tympani muscle: a comprehensive review of the literature / 대한해부학회지

The tensor tympani muscle is structurally important in the middle ear, specifically through its involvement in the impedance of sound in response to intense auditory and non-auditory stimuli. Despite numerous studies, its true function has been debated for many years; questions still remain about its role in auditory and non-auditory reflexes and in sound damping. Some studies suggest that the tensor tympani muscle contracts as a result of non-auditory stimulation such as facial or head movements; others suggest that it contracts due to input from the cochlear nucleus, therefore by way of auditory stimulation. Whatever the cause, contraction of the tensor tympani muscle results in low frequency mixed hearing loss, either to protect the inner ear from loud sounds or to desensitize the ear to self-generated sounds. A review of these studies indicated that the tensor tympani muscle has a wide range of functions, yet the mechanisms of some of them have not been clearly demonstrated. One major question is whether the tensor tympani muscle contributes to sound damping; and if it does, what specific role it serves. The primary purpose of this review article is to explore the functions of the tensor tympani muscle in light of recent research advances.

Discovery of a trans-sellar vascular supply for the pituitary gland / 대한해부학회지

The vasculature of the pituitary gland is discussed briefly and the details of an anatomical discovery of the vessels supplying the pituitary gland provided. Twenty latex injected cadaveric heads were dissected. Any vessels that were found to penetrate the sella turcica and travel to the pituitary gland were documented and measured. Additionally, 25 adult skulls were evaluated for the presence, size, and sites of bony foramina in the floor of sella turcica. Trans-sellar vessels were identified in 65% of specimens. There was a mean of 1.5 vessels per specimen consisting usually of a mixture of veins and arteries. The mean diameter of these vessels was 0.3 mm and the mean length from the sella turcica to the pituitary gland was 2.3 mm. These vessels were concentrated in the most concave part of the sella turcica. In bony specimens, the mean number of transsellar foramina was four. The diameter of these foramina ranged from 0.3 to 0.6 mm in size. The trans-sellar foramina were concentrated near the center part of the sella turcica and had no regular pattern. The pituitary gland receives at least some blood supply and drainage via vessels traveling along the septum of the sphenoidal sinuses and through the sella turcica.Knowledge of such vessels might lead to a better understanding of the vascular supply and drainage of the pituitary gland and would be useful during skull base approaches such as trans-nasal approaches to the pituitary gland.

Morphology of the groove of the inferior petrosal sinus: application to better understanding variations and surgery of the skull base / 대한해부학회지

Although adequate venous drainage from the cranium is imperative for maintaining normal intracranial pressure, the bony anatomy surrounding the inferior petrosal sinus and the potential for a compressive canal or tunnel has, to our knowledge, not been previously investigated. One hundred adult human skulls (200 sides) were observed and documented for the presence or absence of an inferior petrosal groove or canal. Measurements were made and a classification developed to help better understand their anatomy and discuss it in future reports. We identified an inferior petrosal sinus groove (IPSG) in the majority of specimens. The IPSG began anteriorly where the apex of the petrous part of the temporal bone articulated with the sphenoid part of the clivus, traveled posteriorly, in a slight medial to lateral course, primarily just medial to the petro-occipital fissure, and ended at the anteromedial aspect of the jugular foramen. When the IPSGs were grouped into five types. In type I specimens, no IPSG was identified (10.0%), in type II specimens, a partial IPSG was identified (6.5%), in type III specimens, a complete IPSG (80.0%) was identified, in type IV specimens, a partial IPS tunnel was identified (2.5%), and in type V specimens, a complete tunnel (1.0%) was identified. An improved knowledge of the bony pathways that the intracranial dural venous sinuses take as they exit the cranium is clinically useful. Radiological interpretation of such bony landmarks might improve patient diagnoses and surgically, such anatomy could decrease patient morbidity during approaches to the posterior cranial fossa.

Three ipsilateral paracondylar processes with other skull base variations: case report / 대한해부학회지

Variations of the skull base can affect surgical approaches and must be considered when viewing and interpreting radiological imaging. Here, we report a unique collection of bony anatomical variations found on a single adult skull. Three bony excrescences from the occipital bone were identified in the paracondylar region. The smallest of these processes was 7 mm long and was just medial to the mastoid process of the temporal bone and posterior to the styloid process. One bony process was attached to the occipital condyle and was 12 mm in length. The longest of these processes was 17 mm long and arose from the jugular process of the occipital bone. Paracondylar processes can be symptomatic. Knowledge of the bony variations at the skull base is important to those who operate in this region or review and interpret radiological imaging.

Duplication of the ovarian vein: comprehensive review and case illustration / 대한해부학회지

Variations of the ovarian veins can impact imaging diagnosis, surgical procedures of the region, and can be related to clinical findings such as compression of the ureter. Therefore, a good working knowledge of such variants is important to the clinician who interprets imaging of the posterior abdominopelvic region of women and surgeons who operate in this region. Herein, we present a comprehensive review of duplicated ovarian veins and provide a case illustration.

General Accuracy and General Error Factors in Metacognitive Monitoring and the Role of Time on Task in Predicting Metacognitive Judgments / Factores de precisión general y de error general en el monitoreo metacognitivo y el papel del tiempo en la tarea de predecir juicios metacognitivos

Abstract (Gutierrez et al., 2016) conducted an experiment that provided evidence for the existence of two distinct factors in metacognitive monitoring: general accuracy and general error. They found level-1 domain-specific accuracy and error factors which loaded on second-order domain-general accuracy and error factors, which then loaded on a third-order general monitoring factor. In the present study, that experiment was repeated with 170 different participants from the same population. The present study confirmed the original findings. Both studies suggest that metacognitive monitoring consists of two different types of cognitive processes: one that is associated with accurate monitoring judgments and one that is associated with error in monitoring judgments. In addition, both studies suggest domain-specific accuracy and error factors which load onto second-order domain-general accuracy and error factors. Furthermore, in this study we devised an experiment in which general accuracy and general error are treated as separate latent dimensions and found that subjects employ the same resources they use to develop accurate judgments as a "baseline" for calibrating resources necessary in erroneous judgments, but not vice-versa. This finding supports and extends previous findings which suggests that the processes involved in managing metacognitive accuracy are different from those involved in contending with metacognitive error. Future instructional interventions in metacognitive monitoring will be better focused by concentrating on improving accuracy or reducing error, but not both concurrently.

Resumen (Gutiérrez et al., 2016) realizaron un experimento que proporcionó evidencia de la existencia de dos factores distintos en el monitoreo metacognitivo: precisión general y error general. Encontraron factores de error y precisión específicos de dominio de nivel 1 que se cargaron en factores de error y precisión general de dominio de segundo orden, que luego se cargaron en un factor de monitoreo general de tercer orden. En el presente estudio, ese experimento se repitió con 170 participantes diferentes de la misma población. El presente estudio confirmó los hallazgos originales. Ambos estudios sugieren que el monitoreo metacognitivo consiste en dos tipos diferentes de procesos cognitivos: uno que está asociado con juicios de monitoreo precisos y otro que está asociado con errores en los juicios de monitoreo. Además, ambos estudios sugieren que factores de precisión y error específico de dominio se cargan en factores de error y precisión general de dominio de segundo orden. Además, en este estudio diseñamos un experimento en el que la precisión general y el error general se tratan como dimensiones latentes separadas y descubrimos que los sujetos emplean los mismos recursos que utilizan para desarrollar juicios precisos como una "base" para calibrar los recursos necesarios en juicios erróneos, pero no viceversa. Este hallazgo respalda y amplía hallazgos anteriores que sugieren que los procesos involucrados en el manejo de la precisión metacognitiva son diferentes de los involucrados en la lucha contra el error metacognitivo. Es conveniente enfocar las futuras intervenciones de instrucción en la monitorización metacognitiva en mejorar la precisión o reducir el error, pero no ambas al mismo tiempo.

Giant dural arteriovenous fistula in an infant / 대한해부학회지

Dural arteriovenous fistulas (dAVFs) are commonly encountered by the neurosurgeon. Herein, we present a case illustration of an infant presenting with an extremely large fistula that took up a significant part of the intracranial volume. A one-month-old female presented with irritability and failure to thrive. She was the product of a 35-week pregnancy and was delivered vaginally without complications or a difficult labor. Based on the findings of magnetic resonance imaging, the diagnosis of a giant dAVF involving the transerve-sigmoid sinuses was made. The patient was scheduled for an arteriogram but died before the procedure could be performed. Such a case illustrates how large some dAVF can become and at a very early age. As in the present case, the patient was minimally symptomatic. Therefore, the time to intervention after diagnosis is thus, sometimes, critical.

Bilateral venous sinuses of Kelch / 대한해부학회지

Knowledge of the variant anatomy of the intradural venous sinuses is important to anatomists and clinicians alike. Herein, we report a cadaveric case of the rare venous sinus of Kelch, which some have believed is a remnant of the cranioorbital sinuses. To our knowledge, only one other cadaveric case has been reported in the extant medical literature. Clinically, knowledge of such a variant venous sinus can minimize misdiagnoses such as when anatomical variations are noted on imaging. Surgically, such an understanding can avoid intraoperative complications such as iatrogenic hemorrhage.

Rare anastomosis between the ascending pharyngeal and vertebral arteries via the hypoglossal canal: A cadaveric case report / 대한해부학회지

We present a rare case of external carotid artery-vertebral artery anastomosis via the ascending pharyngeal artery, diagnosed upon cadaveric dissection. The ascending pharyngeal artery gave rise to a branch to the hypoglossal canal, which is a variation of a true persistent fetal hypoglossal artery. Knowledge of persistent carotid-vertebrobasilar anastomoses is important as these fetal vessels can contribute significantly to the posterior cerebral circulation. Only 10 cases of external carotid artery-vertebrobasilar artery anastomoses have been reported to our knowledge, and our case presents the first cadaveric dissection of this rare variation.

Chiari 1.5 malformation, accessory odontoid synchondrosis, and ventral compression:case report / 대한해부학회지

The pathogenesis of Chiari 1 malformations has been explained in several different ways, but extensive evidence suggests a relationship between loss of volume within the posterior cranial fossa and Chiari 1 presentations. It is important to be able to differentiate Chiari 1.5 from Chiari 1 malformations as they have similar clinical presentations, but the latter have progressed further and are characterized by caudal herniations of the brain stem through the foramen magnum. Despite the similarities of presentation, Chiari 1.5 malformations have greater rates of complications following posterior decompression surgeries, which are typically performed to relieve ventral compression. An improved understanding of the odontoid synchondroses could lead to better understanding of Chiari malformations and lead to improved treatment of patients with these presentations. Here we present a rare case of an accessory odontoid synchondrosis in a patient with a Chiari 1.5 malformation and ventral compression.

Review of the external carotid plexus: anatomy, function, and clinical manifestations / 대한해부학회지

The external carotid plexus is a combination of postganglionic sympathetic fibers derived from the superior cervical ganglion. This plexus travels along the external carotid artery and continues onto the artery’s branches. The external carotid plexus plays an important role in innervating the mid and lower face. Therefore, implications to the plexus may result in facial abnormalities. Herein, we review the anatomy, function, and review its clinical applications.

Bilateral venous sinuses of Kelch / 대한해부학회지

Knowledge of the variant anatomy of the intradural venous sinuses is important to anatomists and clinicians alike. Herein, we report a cadaveric case of the rare venous sinus of Kelch, which some have believed is a remnant of the cranioorbital sinuses. To our knowledge, only one other cadaveric case has been reported in the extant medical literature. Clinically, knowledge of such a variant venous sinus can minimize misdiagnoses such as when anatomical variations are noted on imaging. Surgically, such an understanding can avoid intraoperative complications such as iatrogenic hemorrhage.

Rare anastomosis between the ascending pharyngeal and vertebral arteries via the hypoglossal canal: A cadaveric case report / 대한해부학회지

We present a rare case of external carotid artery-vertebral artery anastomosis via the ascending pharyngeal artery, diagnosed upon cadaveric dissection. The ascending pharyngeal artery gave rise to a branch to the hypoglossal canal, which is a variation of a true persistent fetal hypoglossal artery. Knowledge of persistent carotid-vertebrobasilar anastomoses is important as these fetal vessels can contribute significantly to the posterior cerebral circulation. Only 10 cases of external carotid artery-vertebrobasilar artery anastomoses have been reported to our knowledge, and our case presents the first cadaveric dissection of this rare variation.

Chiari 1.5 malformation, accessory odontoid synchondrosis, and ventral compression:case report / 대한해부학회지

The pathogenesis of Chiari 1 malformations has been explained in several different ways, but extensive evidence suggests a relationship between loss of volume within the posterior cranial fossa and Chiari 1 presentations. It is important to be able to differentiate Chiari 1.5 from Chiari 1 malformations as they have similar clinical presentations, but the latter have progressed further and are characterized by caudal herniations of the brain stem through the foramen magnum. Despite the similarities of presentation, Chiari 1.5 malformations have greater rates of complications following posterior decompression surgeries, which are typically performed to relieve ventral compression. An improved understanding of the odontoid synchondroses could lead to better understanding of Chiari malformations and lead to improved treatment of patients with these presentations. Here we present a rare case of an accessory odontoid synchondrosis in a patient with a Chiari 1.5 malformation and ventral compression.

Review of the external carotid plexus: anatomy, function, and clinical manifestations / 대한해부학회지

The external carotid plexus is a combination of postganglionic sympathetic fibers derived from the superior cervical ganglion. This plexus travels along the external carotid artery and continues onto the artery’s branches. The external carotid plexus plays an important role in innervating the mid and lower face. Therefore, implications to the plexus may result in facial abnormalities. Herein, we review the anatomy, function, and review its clinical applications.