An educational anatomical diagram overlaid on a lateral chest radiograph, illustrating the surgical division of the mediastinum into three primary compartments: Anterior-Superior (A-S), Middle (M), and Posterior (P). The boundaries of these compartments are demarcated by white dashed lines. Annotations provide statistical data from a study of 566 patients regarding the distribution of mediastinal lesions and the success rate of ultrasound (US) visualization within each zone. The A-S compartment contains 59.4% of lesions (n=336) with an 84% US visualization rate. The M compartment contains 18.6% (n=105) with the lowest US visualization at 1.9%. The P compartment contains 23.3% (n=132) with a 17.4% visualization rate. Specifically noted is 'Vena cava superior syndrome' occurring in 19.9% of cases, with 75.2% US visualization. This infographic serves as a clinical guide for thoracic imaging, highlighting the feasibility of US-guided core needle biopsy based on anatomical localization.

A four-panel medical figure illustrating the surgical anatomy and diagnostic imaging of superior mediastinal masses. Panel 1: A sagittal T2-weighted magnetic resonance imaging (MRI) view highlighting the superior mediastinum (shaded blue) and its anatomical boundaries, specifically the region between the thoracic inlet and the T4-T5 intervertebral disc level. Panel 2: A schematic diagram color-coded by mediastinal compartments (anterior, middle, posterior, and superior) showing the distribution and pathological types of identified lesions, including schwannoma, ganglioneuroma, bronchogenic cyst, and cavernous hemangioma. Panel 3: A sagittal contrast-enhanced MRI demonstrating a large heterogeneous mass in the superior mediastinum with cystic changes. The image labels its close proximity to the superior vena cava and the arch of the azygos vein. Panel 4: An axial MRI slice showing a tumor invading the intervertebral foramen. The annotation notes that while the tumor occupies the neural foramen, it does not invade the spinal cord. This collection is used to teach preoperative assessment of neurovascular involvement and resectability of mediastinal tumors using the da Vinci robotic surgical system.

This dual-panel educational material illustrates the anatomy of the retroperitoneal space using a comparative approach. Panel (a) is a schematic anatomical diagram in axial cross-section. It delineates the three main retroperitoneal compartments: the anterior pararenal space (outlined in blue), containing the pancreas (P) and ascending/descending colon (C); the perirenal space (outlined in green), housing the kidneys (K), adrenal glands, and perirenal fat; and the posterior pararenal space (outlined in yellow dashed lines), located between the posterior renal fascia and the transversalis fascia. The peritoneal cavity (PC) is shown anteriorly. Panel (b) presents a corresponding axial CT scan with intravenous contrast, applying the same color-coded boundary lines to clinical imaging. The CT demonstrates the contrast-enhanced kidneys within the perirenal space and the relative positions of the pancreas and bowel. This comparison aids in understanding fascial planes and the compartmentalization of potential retroperitoneal pathology, such as hematomas or abscesses, which are often confined by these anatomical boundaries.

This diagnostic image is an axial cross-section from a Computed Tomography (CT) scan of the human chest, at the level of the mid-thorax. The image demonstrates a transverse view of the mediastinum and pulmonary parenchyma. Key anatomical structures visible include the thoracic vertebral body located posteriorly, the sternum anteriorly, and the rib cage forming the lateral boundaries. Centrally, the mediastinum contains high-density (bright) vascular structures consistent with the heart and great vessels, including the ascending and descending aorta. The bilateral lungs appear as low-density (dark), air-filled regions flanking the central mediastinal structures. No gross masses, significant pleural effusions, or lobar consolidations are immediately apparent in this single slice. This imaging modality is used in clinical medicine to evaluate thoracic anatomy, assess pulmonary disease, and, when combined with functional imaging like SPECT, localize radiopharmaceutical tracer activity within specific anatomical compartments such as the ileal lumen or renal systems.

This composite medical illustration depicts the surgical and anatomical aspects of compartment syndrome in the gluteal region. The image is divided into two primary sections: a surgical clinical illustration and an anatomical diagram. On the left, a surgical illustration shows a decompressive fasciotomy of the right buttock with the patient in a lateral decubitus position. A large, linear incision through the skin and fascia exposes bulging muscle tissue, which appears edematous and reddish with focal pale areas, suggesting pressure-induced ischemia or muscle fiber disruption. On the right, a color-coded anatomical diagram identifies the three non-distensible fascial compartments of the gluteal region: the tensor fascia lata compartment (positioned anteriorly in red), the gluteus medius and minimus compartment (located centrally with a layered appearance), and the gluteus maximus compartment (positioned posteriorly in green). White arrows indicate the specific spatial boundaries and contents of each compartment. This visual serves as an educational tool for orthopedic surgery and emergency medicine, demonstrating the surgical management (fasciotomy) and the underlying regional anatomy relevant to diagnosing and treating acute gluteal compartment syndrome.

This medical anatomical diagram is a posterior-lateral sketch of the human torso, illustrating the musculature and boundaries of the lumbar triangle, also known as the Triangle of Petit. The diagram highlights the clinical significance of this region for procedures such as the transversus abdominis plane (TAP) block. The anatomical boundaries are clearly labeled: the posterior border is formed by the latissimus dorsi muscle, the anterior border by the external oblique muscle, and the base (inferior border) by the iliac crest. Other visible anatomical landmarks include the rectus abdominis muscle, located medially and anteriorly, and the trapezius muscle superiorly. The illustration demonstrates the convergence of these muscular structures to form a small, triangular area of relative weakness in the abdominal wall, which is a potential site for lumbar hernias. This diagram is designed for educational use in anatomy, regional anesthesia, and general surgery to help students and clinicians identify surface landmarks and deep structural relationships in the lumbar region.

**Imaging Modality:** Non-contrast axial Computed Tomography (CT) of the chest. **Anatomical Region:** Anterior mediastinum at the level of the aortic arch and pulmonary trunk. **Observed Pathology:** A large, well-circumscribed, soft-tissue density mass is present in the anterior mediastinum. The mass is predominantly left-sided but crosses the midline, exerting a mass effect on adjacent vascular structures. It appears relatively homogeneous in attenuation. **Characteristic Visual Features:** * **Location:** Anterior to the ascending aorta and pulmonary artery, posterior to the sternum. * **Morphology:** Lobulated borders with a solid internal composition. * **Surrounding Structures:** The mass is in close proximity to the great vessels; however, no gross invasion of the lung parenchyma or pleural effusion is visualized in this single slice. * **Vascular findings:** A hyperdense (calcified or metallic) focus is noted in the right hilar/paratracheal region, likely representing a calcified lymph node or surgical clip. **Key Diagnostic Features:** The presence of a large anterior mediastinal mass in an adult necessitates the differential diagnosis of the "4 Ts": Thymoma, Teratoma (germ cell tumors), Thyroid (substernal goiter), and "Terrible" Lymphoma. The homogeneity and location are highly suggestive of a thymic epithelial tumor or lymphoma.

This figure presents contrast-enhanced computed tomography (CT) scans of the chest in sagittal (A) and axial (B) planes, focused on the mediastinum. Panel A shows a sagittal reconstruction illustrating a soft tissue mass within the anterior mediastinal space, specifically located in the left lobe of the thymus. A digital measurement indicates the lesion's long axis is approximately 32.6 mm. Panel B provides an axial view at the level of the great vessels, where a red arrow highlights a well-circumscribed, heterogeneous nodular mass. The lesion demonstrates areas of central low density, suggestive of cystic changes or necrosis within the thymic tissue. Key anatomical landmarks visible include the sternum, ascending aorta, and vertebral bodies. This diagnostic imaging is characteristic of an anterior mediastinal tumor, clinically diagnosed in this case as a primary mediastinal seminoma. The images are essential for teaching the differential diagnosis of anterior mediastinal masses (the 'four Ts': thymoma, teratoma, 'terrible' lymphoma, and thyroid) and demonstrating the use of multi-planar CT imaging for tumor localization and characterization.

**Imaging Modality:** Contrast-enhanced computed tomography (CT) of the chest, axial section. **Anatomical Region:** Mediastinum at the level of the aortic arch and superior vena cava (SVC). **Observed Pathology:** A large, heterogeneous, mildly enhancing soft-tissue mass is centered in the anterior mediastinum. The mass demonstrates irregular borders and exerts a mass effect on adjacent vascular structures. Based on clinical context, this is consistent with a mediastinal germ cell tumor. **Characteristic Visual Features:** * **Mass:** The lesion (marked with an asterisk) occupies the prevascular space, displacing the mediastinal pleura laterally. * **Vascular Anatomy:** The superior vena cava and aortic arch are visible. A prominent, linear vascular structure (marked with an arrow) is identified as the azygos vein, seen here in a longitudinal plane as it courses anteriorly to drain into the posterior aspect of the SVC. * **Attenuation:** The mass shows internal areas of varying attenuation, suggesting a complex solid component. **Key Diagnostic Features:** The location in the anterior mediastinum (one of the "4Ts": Thymoma, Teratoma/Germ cell tumor, Thyroid, Terrible Lymphoma) and the patient's age are primary indicators for the differential diagnosis. The image highlights the relationship between the anterior mass and the normal posterior vascular anatomy, specifically the azygos vein arch.

This diagnostic axial CT scan of the chest reveals a soft tissue mass located in the anterior mediastinum, indicated by a white elliptical annotation. The mass exhibits a lobulated morphology and is situated immediately posterior to the sternum and anterior to the great vessels and heart base. In this contrast-enhanced image, the mass shows minimal enhancement relative to the surrounding cardiovascular structures, suggesting low vascularity. Other visible anatomical landmarks include the thoracic vertebrae, bilateral lung fields, and the chest wall. Clinically, this imaging finding is representative of a differential diagnosis for anterior mediastinal tumors, such as thymoma, lymphoma, or a teratoma. The image is a primary resource for students learning to identify mediastinal compartment pathologies and radiological presentations of chest masses.

This diagnostic image is an axial contrast-enhanced CT scan of the chest at the level of the pulmonary artery bifurcation. It demonstrates a large, well-defined mass located in the anterior mediastinum, consistent with a mature teratoma. The mass exhibits heterogeneous density with both cystic (hypodense) and solid (isodense to soft tissue) components, a hallmark of germ cell tumors. Spatially, the lesion is situated posterior to the sternum and anterior to the heart and great vessels, causing notable mass effect and lateral displacement of the adjacent mediastinal structures and the left lung. The presence of varying internal attenuation suggests different tissue types, such as fat, fluid, or soft tissue. This clinical finding is significant for differential diagnosis of anterior mediastinal masses, which includes the '4 Ts': Thymoma, Teratoma, Thyroid (retrosternal goiter), and 'Terrible' lymphoma.

**Imaging Modality:** Computed Tomography (CT), axial section. **Anatomical Region:** Thorax at the level of the heart and lower mediastinum. **Observed Pathology:** The image demonstrates a significant soft-tissue attenuation mass located in the anterior mediastinum. The lesion is characterized by a homogeneous appearance and demonstrates a mass effect, subtly displacing adjacent cardiovascular structures. **Characteristic Visual Features:** * **Mediastinal Widening:** There is an expansive, well-circumscribed soft-tissue density occupying the anterior mediastinal space, consistent with lymphadenopathy or a primary mediastinal tumor. * **Cardiovascular Landmarks:** The mass is situated anterior to the heart and great vessels. The descending aorta and vertebral body appear unremarkable. * **Pulmonary Parenchyma:** The lung fields are largely clear without overt evidence of large pulmonary nodules or consolidations at this level. * **Pleural Space:** No significant pleural effusions are visualized in this section. **Clinical Context/Differentiating Features:** The location and homogeneous morphology in the anterior mediastinum are highly suggestive of lymphoma (e.g., Hodgkin’s or Diffuse Large B-cell Lymphoma), though the differential diagnosis for an anterior mediastinal mass includes thymoma, teratoma, and thyroid lesions.

This educational image pairs an anatomical diagram (a) with a short-axis CT angiography (CTA) image (b) to illustrate the cross-sectional anatomy of the aortic root and surrounding cardiac structures. The focus is on the Sinuses of Valsalva (SOV), showing their spatial orientation and coronary artery origins. The central aortic root is divided into three distinct sinuses: the Right Sinus (SOVrt), from which the Right Coronary Artery originates; the Left Sinus (SOVlt), which gives rise to the Left Coronary Artery; and the Non-coronary Sinus (SOVnc), which lacks a coronary origin and lies adjacent to the interatrial septum. Surrounding structures are clearly labeled: the Right Ventricular Outflow Tract (RVOT) is located anteriorly and to the left; the Right Atrium is lateral to the SOVrt; the Left Atrium lies posteriorly; and the Left Atrial Appendage (LAA) and Pulmonary Veins (PV) are positioned laterally and posteriorly to the left. This material is designed for cardiovascular imaging training to aid in the precise identification of aortic root anatomy during diagnostic evaluation.

Two images from a cardiac gated CT angiography (CTA) of the chest in coronal (a) and axial (b) planes, demonstrating the coronary artery anatomy following systemic therapy for Takayasu's arteritis. In the coronal view (a), a thin red arrow identifies the right coronary artery (RCA) originating from the aortic root. Although better visualized than on previous imaging, it remains significantly stenotic with a narrowed lumen at the ostium. A blue arrow highlights the left coronary artery (LCA), which shows substantial interval improvement in patency. The axial view (b) provides a cross-sectional perspective of the same vessels, with the red arrow pointing to the persistent narrowing of the RCA ostium and the blue arrow indicating the significantly opened lumen of the LCA. These diagnostic images are used to monitor vascular wall thickening and luminal stenosis in large-vessel vasculitis, illustrating the differential response of the coronary ostia to pharmacological treatment.

This diagnostic image set consists of three panels (A, B, C) showing 3D cardiac CT angiography (CTA) reconstructions of the coronary arterial system. Panel A illustrates the left coronary anatomy, highlighting an intact left main coronary artery bifurcating into the left anterior descending (LAD) and circumflex (LCx) arteries. Panel B displays a more detailed view of the circumflex territory where a red arrow identifies a focal area of hypocontrast, suggesting a suspected occlusion of the first marginal branch. There is a visible contrast filling defect in this vessel compared to the surrounding patent coronary branches. Panel C provides a reconstruction of the right coronary artery (RCA), demonstrating a dominant, intact vessel without significant stenosis or calcification. These reconstructions are used in preoperative screening to evaluate coronary anatomy and identify potential ischemic causes of left ventricular free wall rupture (LVFWR) or pseudoaneurysm.

This diagnostic axial CT angiography (CTA) image provides a cross-sectional view of the mid-thoracic cavity, specifically focused on cardiac and mediastinal anatomy. The scan demonstrates the four heart chambers and the descending aorta. A primary clinical finding is an anomalous Left Main Coronary Artery (LMCA) highlighted by a black arrow. The vessel is shown following a septal course, traversing the interventricular septum between the right and left ventricular outflow regions. The image allows for assessment of the arterial caliber and relationship to surrounding myocardial structures, specifically looking for evidence of intra-arterial or intramyocardial compression. Other visible landmarks include the sternum anteriorly, vertebral bodies posteriorly, and bilateral lung parenchyma. This image is a critical educational resource for understanding coronary artery anomalies and the use of gated CTA in evaluating vascular pathways relative to cardiac anatomy.

Educational infographic illustrating the CT Coronary Angiography (CTCA) semi-quantitative plaque scoring system, based on the Society of Cardiovascular Computed Tomography 17-segment model. The top section features two 3D volume-rendered heart reconstructions labeling key coronary anatomy: Right Coronary Artery (RCA), PDA, PLB, Left Main (LMCA), LAD, LCx, and branches D1/D2 and OM1/OM2. Tables define the Segment Score weighting factors for right and left dominance, and the Stenosis Score (1% to 100%). The bottom-left panels provide curved multiplanar reconstructions (cMPR) of coronary vessels showing three distinct plaque morphologies: 'Calcified' (high-attenuation/bright), 'Mixed' (heterogeneous density), and 'Soft' (low-attenuation/grey). A 'Plaque Score' table assigns multipliers (x1 for calcified, x2 for mixed, x3 for soft) to calculate the Soft Plaque Score (SPS) alongside the standard Gensini score and Agatston calcium score. This resource is designed for cardiology and radiology training on atherosclerotic burden assessment.

Two-panel diagnostic imaging showcasing cardiac anatomy via CT coronary angiography. Panel 1 features a 3D volume-rendered reconstruction of the heart and aorta, highlighting the spatial relationship of the coronary vasculature. Panel 2 presents an oblique maximum intensity projection (MIP) providing a cross-sectional view of the aortic root and arterial origins. The images demonstrate a congenital anomaly: an anomalous origin of the right coronary artery (RCA) from the left coronary sinus (ARCA-LCS). The yellow arrows indicate the RCA, which originates from the left sinus and follows an interarterial course between the aorta and pulmonary artery. The red arrows indicate the left coronary artery (LCA), also originating from the left sinus. This visual illustrates a high-risk coronary anomaly where the interarterial course can lead to mechanical compression of the vessel during physical exertion, which is a critical finding for cardiovascular risk assessment in clinical practice.

This diagnostic image composite features axial maximal intensity projection (MIP) coronary CT angiography (A, C) and 3D volume-rendered reconstructions (B, D) illustrating Anomalous Origin of the Coronary Artery from the Opposite Sinus (ACAOS). Panels A and B demonstrate an anomalous Right Coronary Artery (RCA, arrow) arising from the Left Coronary Sinus (LCS). The RCA follows a high-risk interarterial course, passing between the Aorta (AO) and the Main Pulmonary Artery (MPA). Panels C and D show a variant where the RCA (arrow) originates from the Non-Coronary Sinus (NCS), passing near the Right Ventricular Outflow Tract (RVOT). Key anatomical landmarks labeled include the Left Atrium (LA), Right Coronary Sinus (RCS), and the aortic root. This visual material is used in cardiovascular radiology to teach the identification of coronary anomalies and to assess the spatial relationship between anomalous vessels and great arteries, which is critical for determining the risk of sudden cardiac death and planning surgical interventions like coronary deroofing.

This diagnostic image consists of two Computed Tomography (CT) coronary angiogram reconstructions (A and B) demonstrating an anomalous origin and course of the left main coronary artery (LMCA). Image A is an axial reconstruction showing the LMCA (yellow arrow) taking a high-risk interarterial course between the ascending aorta (red arrow) and the pulmonary outflow tract (blue arrow). Image B utilizes Maximum Intensity Projection (MIP) reconstruction to highlight a clinically significant narrowing of the anomalous LMCA (black arrow) as it traverses between the great vessels, exhibiting an intramural or 'slit-like' appearance characteristic of malignant coronary artery anomalies. This case illustrates the diagnostic role of CT angiography in identifying congenital coronary variants and assessing for potential vascular compression. The findings are relevant for cardiology and radiology specialties, focusing on the pathophysiology of sudden cardiac death or myocardial ischemia related to anomalous coronary anatomy.

**Imaging Modality:** Computed Tomography Angiography (CTA), presented as a Maximum Intensity Projection (MIP) reconstruction of the heart and great vessels. **Anatomical Region:** Thorax, focusing on the aortic root and coronary arteries. **Observed Pathology:** Anomalous origin of the right coronary artery (RCA). **Characteristic Visual Features:** The image demonstrates the RCA arising anomalously from the left coronary sinus of the aorta, rather than the right sinus. The vessel follows an "interarterial course," passing acutely between the ascending aorta and the main pulmonary artery. Annotated labels identify the aorta and pulmonary artery, with an arrow highlighting the RCA as it traverses the space between these two major vessels before descending into the right atrioventricular groove. **Key Diagnostic Features:** - **Origin:** Left coronary sinus. - **Course:** Malignant/interarterial trajectory, which carries a risk of compression during exercise or increased cardiac output. - **Morphology:** Visible narrowing or "slit-like" appearance at the ostium and proximal segment as it passes between the great vessels. **Clinical Context:** This is a classic representation of a high-risk coronary anomaly (Anomalous Aortic Origin of a Coronary Artery - AAOCA) visualized via cardiac CT for surgical planning or risk stratification.

This composite diagnostic image consists of three panels demonstrating high-risk anatomical features of an anomalous origin of a coronary artery arising from the opposite sinus (ACAOS) with an interarterial course (IAC), visualized via Coronary Computed Tomography Angiography (CCTA). Panel 1 provides a 3D reconstruction showing the right coronary artery originating from the left sinus of Valsalva and traversing between the aorta and pulmonary artery. Panel 2 utilizes multiplanar axial reconstruction to highlight an acute takeoff angle and an intramural course, where the vessel is embedded within the aortic wall (indicated by an asterisk). Panel 3 demonstrates 'slit-like morphology' in a double oblique view. It quantifies the proximal luminal narrowing (Point A) compared to a distal reference point (Point B), with an interarterial course length measurement of 19.5 mm. These features are clinically significant as markers for potential myocardial ischemia or sudden cardiac death, facilitating surgical planning and risk stratification in cardiology and radiology.

Diagnostic Image: Cardiac CT Angiography (CCTA) axial slices demonstrating various coronary artery anomalies. Panel A shows an anomalous origin of the left anterior descending (LAD) coronary artery from the right coronary artery (RCA), indicated by a black arrow. Panel B illustrates the LAD passing in close proximity to the pulmonic valve, with arrows highlighting the vessel's course. Panel C depicts the RCA originating from the left coronary cusp (LCC) with a high-risk interarterial course between the aorta and the pulmonary artery, marked by a black arrow. These images showcase congenital coronary anomalies often associated with structural heart diseases like Tetralogy of Fallot. The visual focus is on the anomalous takeoff points (ectopic origins) and the subsequent anatomical pathways (prepulmonary vs. interarterial) relative to the great vessels and heart valves. This content serves as an educational resource for cardiology and radiology specialties to identify potentially malignant coronary vessel trajectories using non-invasive imaging.

A multi-panel clinical diagnostic image set demonstrating an anomalous origin of the right coronary artery (RCA) from the left coronary sinus. Panels A and B are CT angiography (CTA) images in coronal and axial planes, respectively, showing the interarterial course of the RCA. Yellow arrows highlight the vessel passing between the aorta (AO) and the pulmonary artery (PA). Panels C and D provide three-dimensional colored volume renderings of the cardiac anatomy and coronary arterial tree. These renderings illustrate the spatial relationship of the AO and the origin of the coronary arteries, highlighting the 'malignant' course of the anomalous vessel as it exits the aorta and traverses the space between the major outflow tracts. The imagery is intended for advanced medical education regarding congenital coronary anomalies, specifically the risk of compression associated with interarterial pathways. Labels 'AO' and 'PA' identify the primary vascular landmarks, while panels C and D emphasize the superficial and deep branching patterns of the coronary circulation.