Mathias Orellana

• Master of Education
• Human Anatomy Teacher at Andrés Bello University

Background and Objectives: The pancreas receives blood through a complex network of multiple branches, primarily originating from the celiac trunk (CeT) and the superior mesenteric artery (SMA). This blood supply is structured into three main arterial groups, each serving different regions of the pancreas to effectively support its endocrine and ex...

Background: Neuropathic pain (NP) and cancer are caused by nerve damage due to cancer or treatments such as chemotherapy, radiotherapy, and surgery, with a prevalence that can reach up to 40%. Causes of neuropathic cancer pain (NCP) include direct nerve invasion or compression by the tumor, as well as neural toxicity associated with treatments. Thi...

Background: The internal jugular vein (IJV) is a vascular structure that is responsible for the venous drainage of both the head and neck and is commonly found posterior to the internal carotid artery and adjacent to cervical lymph nodes or nerve structures such as the glossopharyngeal and accessory nerves. As a vagal nerve, it is an important refe...

The hepatic portal vein is the main vascular route responsible for collecting blood from the liver, spleen, pancreas, stomach, gallbladder, and intestines. Its key function is to metabolize the components acquired from the blood. The objective of this study was to analyze the characteristics of HPV variants and understand the possible clinical cons...

A.; Meneses Caroca, T.; Rojo-Gonzalez, J.; Orellana-Donoso, M.I.; Nova-Baeza, P.; Suazo-Santibañez, A.; Sanchis-Gimeno, J.; Gutierrez-Espinoza, H. Hepatic Hilum Variations and Their Clinical Considerations in the Liver: A Systematic Review and Meta-Analysis. Abstract: Background: The liver has a region called the hepatic hilum (HH) where structures...

Introduction Knowledge of anatomical variants that affect the hepatic duct (HD) are of particular clinical relevance during hepatobiliary surgical procedures. More specifically, the aberrant anatomy of the common HD is the most common anatomical variation affecting the biliary tree. Below, we describe different classifications of anatomical variant...

Rationale The pectoralis major and minor muscles, located in the anterior chest wall, are crucial for upper limb movements. Patient concerns Their nonsyndromic absence is rare but significant for surgical procedures involving the axillary and pectoral regions. Diagnoses Ultrasound can confirm the diagnosis and delimit the extent of the muscular a...

Background: Metabolic syndrome refers to the coexistence of several known cardiovascular risk factors, including insulin resistance, obesity, atherogenic dyslipidemia, and hypertension. These conditions are interrelated and share underlying mediators, mechanisms, and pathways. Improvement in dietary habits has been shown to improve metabolic param...

Citation: Bruna-Mejias, A.; Baeza, V.; Gamboa, J.; Baez Flores, B.; San Martin, J.; Astorga, C.; Leyton, J.; Nova-Baeza, P.; Orellana-Donoso, M.; Suazo-Santibañez, A.; et al. Use of Ketamine in Patients with Multifactorial Neuropathic Pain: A Systematic Review and Meta-Analysis. Abstract: Neuropathic pain (NP) is a heterogeneous group of conditions...

Purpose: The most common anomaly is an anomalous left coronary artery originating from the pulmonary artery. These variants can be different and depend on the location as well as how they present themselves in their anatomical distribution and their symptomatological relationship. For these reasons, this review aims to identify the variants of the...

Objectives: Diabetic peripheral neuropathy (DPN) is a chronic complication of diabetes mellitus (DM) with symptoms like intense pain and impaired quality of life. This condition has no treatment; instead, the pain is managed with various antidepressants, including duloxetine. The aim of this study is to analyze the evidence on the efficacy of dulox...

Background: Variations in renal veins are quite common, and most people do not experience issues due to them. However, these variations are important for healthcare professionals, especially in surgical procedures and imaging studies, as precise knowledge of vascular anatomy is essential to avoid complications during medical interventions. The purp...

The mental foramen (MF) is an opening found bilaterally on the anterolateral aspect of the mandible; it can be round or oval and have different diameters. One of the anatomical variants of the jaw is the presence of an accessory mental foramen (AMF). These are usually smaller than the MF and can be located above, below, or to the sides of the main...

Background: Glioblastoma is a primary malignant brain tumor; it is aggressive with a high degree of malignancy and unfavorable prognosis and is the most common type of malignant brain tumor. Glioblastomas can be located in the brain, cerebellum, brainstem, and spinal cord, originating from glial cells, particularly astrocytes. Methods: The database...

Background: Coronary arteries originate from the first portion of the aorta, emerging from the right and left aortic sinuses. They traverse through the subepicardium and coronary sulcus to supply the myocardium during diastolic function. The objective of this review was to understand how the hypoplasia and agenesis of the coronary arteries are asso...

Purpose The vertebral artery (VA) is a vital branch of the subclavian artery, coursing through the transverse foramina of the cervical vertebrae, and playing a crucial role in irrigating the posterior region of the arterial cerebral circle, also known as the Polygon of Willis. Among the various possible alterations that can affect the VA, vertebral...

Background Recent literature highlights anomalous cranial nerves in the sinonasal region, notably in the sphenoid and maxillary sinuses, linked to anatomical factors. However, data on the suspended infraorbital canal (IOC) variant is scarce in cross-sectional imaging. Anatomical variations in the sphenoid sinuses, including optic, maxillary, and vi...

Objective: The aim of this study was to describe the main anatomical variants and morphofunctional alterations in the lower limb that compress surrounding nervous structures in the gluteal region, thigh region, and leg and foot region. Methods: We searched the Medline, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS databases from their...

Background A high incidence of anatomical variations in the origin of the branches of the aortic arch has been reported, Nowadays, this variation is considered the most frequent in the aortic arch, its prevalence being estimated between 0.5% and 2.5% of the population. To understand its origin, knowledge of embryonic development is necessary. Meth...

Background Situs inversus is a rare congenital anatomical variant that involves a group of anomalies regarding the arrangement of intrathoracic and intraabdominal organs. Being able to find in the abdominal region the liver, gallbladder, inferior vena cava, and head of the pancreas and ascending colon on the left side of the abdomen, while on the r...

This systematic review explores the most current evidence regarding aquatic exercise therapy in patients with knee osteoarthritis (OA) pain. The review also seeks to provide guidelines for the best approach and treatment for patients experiencing this type of pain. To study the relationship between aquatic exercise and knee osteoarthritis, with emp...

Humans throughout history have shown similarities between both their cephalic and facial complexion, among certain ethnic groups, due to genetic and demographic factors. Several studies have demonstrated the different constitutions of specific groups of people in order to generate data of a certain population or group. The present research aims to...

VALENZUELA-FUENZALIDA, J. J.; NOVA-BAEZA, P. & ORELLANA-DONOSO, M. Anatomical characteristics, relations, and clinical considerations of the facial index and cephalic index in young Chileans aged between 18 and 21 years. Int. J. Morphol., 41(6):1720-1726, 2023. SUMMARY: Humans throughout history have shown similarities between both their cephalic a...

Background This systematic review explores the most current evidence regarding the mechanisms of neuropathic pain in patients with different types of diabetes and how this pain affects different functional and structural components of the neuroanatomical pain pathways. The review also seeks to provide guidelines for the best approach and treatment...

Objective: The aim of this study was to describe the prevalence of anatomical variants in the bifid mandibular condyle (BMC) and report its association with temporomandibular joint (TMJ) pathology. Methods: We searched the Medline, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS databases from their inception up to September 2023. Two au...

Cervical vertebrae may exhibit the anomalous presence of a double transverse foramen (DTF) that may impact the anatomy of related structures that traverse the cervical region, such as the vertebral artery (VA). This retrospective anatomical study utilized CT angiography cervical scans to examine the prevalence of DTF, VA, and TF areas. The subjects...

RESUMEN Introducción: se ha sugerido que las neuronas espejo (MN, por sus siglas en inglés) desempeñan un papel fundamental en los procesos sociales de orden superior, incluido el aprendizaje motor, la comprensión de la acción, el aprendi-zaje por imitación, la toma de perspectiva, la comprensión de las emociones faciales y la empatía. Sin embargo,...

Objective The objective of this review is to investigate and analyze the anatomical variations present in the maxillary sinus (MS), through the examination of the prevalence of these variations, as well as the corresponding prevalence of clinically significant pathologies and complications associated with them. Methods The search process was carri...

Objective: This systematic review analyzes the anatomical variants in the pancreas and its ductal system to report on their association with pancreatic pathologies. Methods: We conducted a search of the MEDLINE, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS databases from their inception to July 2023. The methodological quality was...

ABSTRACT Introduction: In clinical practice, the functional tests used to assess the risk of falls require precision techniques and elements that avoid subjectivity. The use of the Wii Balance Board (WBB) is an alternative to the above, since it is an inexpensive, portable tool that allows extracting variables that are related to the phenomenon un...

Introduction: The recurrent laryngeal nerve (RLN) is the structure responsible for sensory and motor innervation of the larynx, and it has been shown that its lesion due to a lack of surgical rigor led to alterations such as respiratory obstruction due to vocal cords paralysis and permanent phonation impairment. The objectives of this review were...

Background: The spleen is the largest secondary immune organ in the body. Knowledge regarding the normal splenic vascular anatomy and its anatomical variants is crucial in the medical practice of surgeons and radiologists and is useful for diagnostic evaluations and the guidance of various surgical procedures. Hence, in this research, we aim to cha...

Introduction The pancreas is retroperitoneal gland located the posterior wall of the abdomen, and plays a central role in digestion and absorption, as well as in the use and storage of energy substrates. Due to its location, as an external organ deep in the retroperitoneum, its irregular surface, its smoothness, its close and varied relationships t...

The subject of human anatomy is a critical subject in terms of the failure rate in many universities in the world, this attributed to the complexity and the large amount of new content for the student, so knowing the failure and how it affects the continuity of the student in the career, it is important to have new and better guidelines in the subj...

Introduction: Anatomically, the aberrant subclavian artery is the last branch of the aortic arch. On its way to the right upper limb it runs posterior to the esophagus. During this passage it can compress the esophagus, producing Lusoria Dysphagia. Materials and methods: Different databases were subjected to a systematized literature search, usi...

Introduction: Anatomically, the vascularization and venous drainage of the kidney is provided by the renal artery and vein. Generally, the kidney consists of a renal artery originating in the abdominal aorta, which later divides into an anterior and posterior branch, however it is not uncommon to find more than one emerging from the abdominal part...

Introduction: The sciatic nerve innervates most of the muscles of the lower limb, so any alteration in it'sits function or clinical presentation could directly affect the functioning of the lower limb. Therefore, the normal anatomy, anatomical variants and how these can influence clinical implications in the gluteal region are of importance in dai...

Introduction: The spleen is an abdominal organ whose weight represents 0.2% of total body weight. It contains 3% of cardiac output, constituting one of the most vascularized abdominal organs. This corresponds to the thickness of your blood vessels and their main function, which is to destroy old erythrocytes and the production of blood cells for t...

Introduction: Human Anatomy is one of the pillars for the training of professionals in the health area, which generates a great challenge for the curricular profile of the teachers who teach these courses, this in relation to the different profiles proposed by each career of the health in which human anatomy is taught, where many times this must b...

Introduction: With advances in technology over the past decades, reductions in teaching time, increasing class sizes, and increasing costs of cadaver-based instruction, computer- based learning resources are used every increasingly in anatomy curricula to encourage student learning, and its use has been found to increase anatomy teaching, enhance...

Introduction: Anatomically, the maxillary sinus (MS) and maxillary bone is a complex structure to study, due to its walls and its communication with different structures such as the respiratory system, upper teeth and the orbital cavity, specifically the floor of this cavity and the inferomedial region. The MS is a pneumatic cavity housed within t...

IntroductionThe anatomical variations of the mandibular canal have been described according to the number of additional branches it presents, bifid and trifid. Within the bifids we can also find subtypes of variations such as the retromolar mandibular canal. These anatomical variations can have important clinical implications for the work of dental...

Introduction The thalamus plays an important role in different brain functions which could include the following functions; memory, emotions, mediator in general cortical alert responses, sensorimotor control and one of the main ones which is to be a nucleus for processing sensitive information (including taste, somatosensory, visual and auditory)...

Introduction: In the upper there are different neural entrapment sites that can be associated with neighboring structures which in turn can mimic other neural entrapments syndromes. The objective of this study was to review the literature concerning neuromusculoskeletal anatomical variations in the upper limb and their possible clinical correlation...

Introduction: Osteoarthritis (OA) is the most common joint disease, increases with age and it is estimated that in those over 60 years of age more than 80 % have OA in at least one joint. Currently, the evidence regarding MT in hip OA has had unclear results. Therefore, the main objective of this study is to determine the effectiveness and recommen...

The lateral pterygoid muscle is a chewing muscle that is found bilaterally in the cranial region. Anatomically , the lateral pterygoid muscle is made up of two bellies, an upper belly and a lower belly. Its anatomical description present in the scientific literature showed that there is an anatomical difference or variation, mainly the insertions o...

Introduction For several decades and centuries, the use of corpses and plastic samples have been the gold standard for teaching human anatomy in undergraduate. The constant technological evolution worldwide has not left human anatomy behind. In relation to this, since the end of the 20th century and the beginning of the 21st century an enormous amo...

The lateral pterygoid muscle (LPM) is a chewing muscle that is found bilaterally in the cranial region, anatomically the LPM is made up of two bellies, an upper belly and a lower belly. The anatomical description of the LPM present in the scientific literature, showed that there is an anatomical difference or variation mainly in the insertions of t...

Introduction The upper extremity is one of the most complex and functional body segments of the human body formed by a wide variety of structures, whether musculoskeletal, nervous system and integumentary system, which together allow great functionality in many daily life activities. In case any type of alteration of these structures will affect th...

Letter