UNASSIGNED: Medical students are frequently introduced to medical school curricula through anatomy coursework, which often includes histology and embryology content. As medical education has increasingly emphasized integration of content areas, use of activities such as case-based learning (CBL) sessions has grown. Little published work has demonstrated the effectiveness of CBL sessions in integrating anatomy, embryology, and histology on first-year medical students\' ability to improve content mastery and adapt their study techniques.
UNASSIGNED: We developed a CBL session that included anatomy, embryology, and histology content covering the upper extremity and breast pathology that was taught to incoming first-year medical students (N = 51) during a prematriculation program in the summers of 2022 and 2023. The session involved completion of an individual pre- and postsession quiz; group completion of clinical cases involving image interpretation, matching exercises, and construction of diagrams, flowcharts, or tables; and a postsession survey with Likert-style and free-response questions about preparation and session effectiveness.
UNASSIGNED: Postsession quiz scores significantly improved (p < .001). On the postsession survey (response rate: 59%), students commented that they enjoyed the real-life application and integration of the cases and that the sessions improved their understanding of the connections between content areas. Other comments demonstrated that students were evaluating and adapting their study approach in preparation for the sessions, often using techniques introduced and practiced in the sessions.
UNASSIGNED: CBL sessions can provide opportunities to incoming first-year medical students to practice, adapt, and evaluate study techniques while delivering integrated content.

Cerebral persistent primitive arteries are uncommon and associated with cerebrovascular diseases, like cerebral aneurysms. They can cause vertebrobasilar ischemia and neuropathy of the cranial nerves. The authors present a patient with trigeminal artery associated with giant partially thrombosed cavernous internal cerebral artery aneurysm.
Церебральные персистирующие нормальные примитивные артерии имеют крайне низкую распространенность в популяции и часто сочетаются с различными сосудистыми заболеваниями головного мозга, могут быть ассоциированы с церебральными аневризмами, становиться причиной нарушения мозгового кровообращения в вертебробазилярном бассейне, а также причиной неспецифических невритов черепно-мозговых нервов. В работе представлено наблюдение сочетания тройничной артерии и гигантской частично тромбированной аневризмы кавернозного отдела внутренней сонной артерии.

UNASSIGNED: Intestinal malrotation is a congenital abnormality predominantly diagnosed in children, with only a few cases reported in adults. Patients may be incidentally identified during unrelated surgical procedures or postmortem examinations. It is crucial to promptly recognize this condition to prevent severe complications such as bowel ischemia and potential fatality.
METHODS: A 40-year-old male presented to the Emergency Department after a child jumped on his abdomen with complaints of acute left upper quadrant abdominal pain progressing to be generalized. Examination showed pallor, abdominal tenderness without guarding or rigidity, and intact bowel sounds. Preoperative diagnostic tools revealed intestinal malrotation confirmed during the laparotomy, prompting the performance of Ladd\'s procedure to address the malrotation.
UNASSIGNED: Disruption in the normal embryological development of bowel is the cause of intestinal malrotation. The role of additional surgery especially in patients with asymptomatic disease related to malrotation is debated.
CONCLUSIONS: Intestinal malrotation is rare in adults and often found incidentally during evaluation for unrelated medical conditions. Timely identification and surgical intervention usually result in positive outcomes. Our case underscores the incidental discovery of malrotation during the evaluation of blunt abdominal trauma, treated with Ladd\'s procedure. This is particularly significant due to geographical constraints associated with the patient\'s rural origin, as untreated malrotation could lead to complications in future occurrences.

This study presents the routine prosection findings of a 74-year-old male anatomical donor, whose cause of death was attributed to anoxic brain injury secondary to cardiac arrest and acute exacerbation of chronic obstructive pulmonary disease (COPD). The patient exhibited a significant medical history, including severe COPD, chronic heart failure, atrial fibrillation, hypertension, stage III chronic kidney disease, heavy alcohol abuse, obesity, coronary artery disease, peripheral edema, triple bypass surgery, and right hip replacement. A detailed examination of the upper extremities revealed anomalies within the brachial plexus, with a more pronounced presence on the left side. This particular donor deviates from the expected \"typical\" brachial plexus anatomy, with a lack of convergence into a lateral cord and an anomalous convergence into a superior trunk. To ensure optimal patient care and procedural outcomes, a collaborative approach between surgeons and anesthesiologists that is grounded in a comprehensive understanding of these anatomical nuances is essential. Therefore, this study aims to comprehensively investigate the identified brachial plexus anomalies, elucidate their embryological origins, and explore their clinical implications. Through these objectives, this research contributes to a broader understanding of anatomical variations and their relevance in medical practice.

During routine dissection of 11 cadavers that originated with the Body Donor Program at Philadelphia College of Osteopathic Medicine (PCOM) Georgia, a 69-year-old African American male with bilateral extensor anomalies in the dorsal forearm compartment was encountered. The distinct muscle belly, identified as the extensor medii proprius (EMP), originated from the distal ulna and was inserted near the dorsal aponeurosis of the third digit. Manual traction of the right EMP tendon resulted in the extension of the third digit, suggesting the functional significance of the anomalous muscle. This case study analyzes the EMP found during dissection, as well as the anomalous muscle\'s prevalence, embryologic origin, and clinical relevance. The presence of the EMP muscle and tendon can be considered when assessing pain in the dorsum of the hand and when preparing for surgical repair or tendon transfer.

Ectopic thyroid tissue is a rare condition manifested as the appearance of thyroid tissue outside the thyroid gland. Here, we report a case of ectopic thyroid tissue in the breast. A 48-year-old Chinese woman who was diagnosed with breast cancer received modified radical mastectomy. A thyroid tissue was found on subsequent pathological examination. The ectopic thyroid tissue was confirmed by immunohistochemistry staining of thyroid biomarkers, including thyroglobulin, thyroid transcription factor-1, and thyroid peroxidase. Currently, abnormal thyroid anlage descent is the main theory to explain ectopic thyroid tissue, especially lingual thyroid. However, it is far-fetched to explain the pathogenesis of ectopic thyroid tissues existed in organs or tissues far from thyroid such as iris, cardiac, pulmonary, duodenal, adrenal, and vertebral. Here, we reviewed the previous cases of ectopic thyroid tissue in breast and proposed a \"entoderm migration\" theory to explain distant ectopic thyroid tissues based on embryonic development perspective.

Agenesis or dysgenesis of the corpus callosum may occur due to ischemic, toxic, traumatic, or another insult to the fetus in the first trimester. Occasionally, such a malformation is associated with an interhemispheric cyst, among other central nervous system anomalies. Holoprosencephaly tends to mimic this radiographic presentation, which is where key imaging findings are helpful to differentiate between these entities. We present a 56-year-old male patient who was found to have a monoventricle, corpus callosum agenesis, interhemispheric cyst, and a Dandy-Walker malformation. The patient presented with a right acetabular fracture with computed tomography (CT) of the brain revealing the congenital brain abnormalities. The patient\'s past medical history was notable for a seizure disorder identified during early adulthood. The CT scan of the head revealed a large monoventricle with an associated midline dorsal interhemispheric cyst and a Dandy-Walker malformation. The absence of both the corpus callosum and septum pellucidum was noted, with the presence of a monoventricle, leading to an initial differential of holoprosencephaly. Further review of the findings suggested instead a rare congenital presentation consisting of corpus callosum agenesis and an interhemispheric cyst. This case highlights a unique radiographic presentation of multiple brain anomalies, rarely presented in non-pediatric literature, which may help determine appropriate surgical and medical management for similarly affected adult individuals.

Ovarian absence is an uncommon condition that most frequently presents unilaterally. Several etiologies for the condition have been proposed, including torsion, vascular accident, and embryological defect. A systematic review was conducted to describe the clinical presentation of ovarian absence, as well as its associations with other congenital anomalies, through a systematic search of Cochrane Library, ClinicalTrials.gov, Google Scholar, Ovid Embase, Ovid Medline, PubMed, Scopus, and Web of Science. Exclusion criteria included cases with suspicion for Differences of Sex Development, lack of surgically-confirmed ovarian absence, and karyotypes other than 46XX. Our search yielded 12,120 citations, of which 79 studies were included. 10 additional studies were found by citation chasing resulting in a total 113 cases including two unpublished cases presented in this review. Abdominal/pelvic pain (30%) and infertility/subfertility (19%) were the most frequent presentations. Ovarian abnormalities were not noted in 28% of cases with pre-operative ovarian imaging results. Approximately 17% of cases had concomitant uterine abnormalities, while 22% had renal abnormalities. Renal abnormalities were more likely in patients with uterine abnormalities (p < 0.005). Torsion or vascular etiology was the most frequently suspected etiology of ovarian absence (52%), followed by indeterminate (27%) and embryologic etiology (21%). Most cases of ovarian absence are likely attributable to torsion or vascular accidents, despite many references to the condition as \"agenesis\" in the literature. Imaging may fail to correctly diagnose ovarian absence, and diagnostic laparoscopy may be preferable in many cases as genitourinary anatomy and fertility considerations can be assessed during the procedure. Fertility is likely minimally or not affected in women with unilateral ovarian absence.

UNASSIGNED: Thyroglossal duct cysts are a common congenital anomaly in the neck which usually present in adulthood as a midline neck swelling the location of which can vary from lingual, suprahyoid, infrahyoid and suprasternal.
UNASSIGNED: Here we have described the case of a thirty-year-old male who presented with a history of recent onset dysphonia and an unnoticed neck swelling. Clinical examination revealed a midline 2 x 2 cm cystic lesion in the neck. On further evaluation using laryngoscopy and computed tomography the patient was found to have a smooth mucosa-covered cyst in the subglottic location. Surgical excision of the cyst was done via laryngofissure and the postoperative course was uneventful. The postoperative biopsy revealed a subglottic thyroglossal cyst.
UNASSIGNED: Though there have been reports of intralaryngeal extension of thyroglossal duct cysts, the subglottic location is extremely rare. Through this case report, we would like to highlight the atypical presentation of thyroglossal duct cysts and how an innocuous pathology can turn potentially life-threatening. We would also recommend avoiding a fine needle aspiration cytology in such cases due to the critical location.

Several theories have been postulated to explain the embryogenesis of central nervous system (CNS) neurenteric cysts (NCs), but the exact mechanism remains poorly understood. Of those, the neurenteric canal migration hypothesis suggesting endodermal cell migration through the neurenteric canal and settling among ectodermal cells prior to neural tube closure might be the most robust as it explains, in contrast to other hypotheses, the existence of lateral supratentorial lesions, which are extremely rare, compared to their infratentorial counterparts. This mechanism might be supported by past medical history or the coexistence of CNS epidermoid cysts, which are thought to arise due to improper neural tube closure potentially increasing the probability of endodermal migration and subsequent NC development, yet there are no reported cases in the literature. We present a case of a patient with a history of a previously resected intracranial epidermoid cyst, representing three simultaneous pathologies including a laterally based right frontal NC along with a right corona radiata cavernous malformation lesion, and right middle cerebral artery bifurcation aneurysm. The three lesions were treated microsurgically in one operative session without complications. We discuss the case and review the relevant pathoembryology of laterally based supratentorial NC.