Pharynx

Pharynx

pediagenosis    October 07, 2026   

Pharynx

The pharynx is a musculomembranous tube; much of its anterior wall is absent due to the fact that the right and left nasal cavities, oral cavity, and larynx open into its anterior side. It extends from the base of the skull to the inferior border of the cricoid cartilage at the level of the lower margin of the sixth cervical vertebra, at which time it becomes continuous with the esophagus. In addition to the cavities already listed, the pharynx also communicates with the middle ear on each side by means of the auditory (eustachian) tube; this fact explains how infections spread from the pharynx to the middle ear, making a total of seven cavities with which it has communication. The transverse diameter of the pharynx exceeds the anteroposterior diameter, which is greatest superiorly and is diminished to nothing inferiorly where the anterior and posterior walls are in contact unless separated during the act of swallowing. The transverse diameter does not differ greatly throughout the length of the pharynx, except where it narrows at the lower end.

Bowenoid Papulosis: Symptoms, Causes, Diagnosis and Treatment

Bowenoid Papulosis: Symptoms, Causes, Diagnosis and Treatment

pediagenosis    October 06, 2026    Comment   

BOWENOID PAPULOSIS

Bowenoid papulosis is considered to be a special variant of squamous cell carcinoma (SCC) in situ that is caused by the human papillomavirus (HPV) and is located predominantly in the genital region, particularly on the penile shaft. As with other HPV-induced genital skin cancers, HPV 16, 18, 31, and 33 are the more common viral types, although many other subtypes have been found in these lesions. Bowenoid papulosis is considered by some to be a precancerous lesion with a low risk of developing invasive properties and by others as a true SCC in situ. This lesion does have a low risk of invasive transformation; if it is treated, the prognosis is excellent. It is believed that approximately 1% of all bowenoid papulosis lesions will develop into invasive SCC.

Cross Section at T12–L1, Intervertebral Disc Anatomy

Cross Section at T12–L1, Intervertebral Disc Anatomy

pediagenosis    October 06, 2026    Comment   

Cross Section at T12–L1, Intervertebral Disc Anatomy

Transverse colon, Ascending colon (right colic flexure) (Common) bile duct, Descending (2nd) part of duodenum, Inferior vena cava, Right suprarenal gland, Superior pole of right kidney, Right crus of respiratory diaphragm, T12–L1 intervertebral disc,

Stomach in Situ Anatomy

Stomach in Situ Anatomy

pediagenosis    October 06, 2026    Comment   

Stomach in Situ Anatomy

Falciform ligament, Gallbladder, Pylorus, Caudate lobe of liver, Duodenum, Left lobe of liver, Head of pancreas, Hepatic portal vein, Inferior vena cava, Liver, left lobe, Body of pancreas, Superior mesenteric artery, Abdominal aorta, Hepatoduodenal ligament, Hepatogastric ligament, Lesser omentum, Abdominal part of esophagus, Cardiac notch (incisure), Fundus of stomach, Respiratory diaphragm.

Pulmonary Agenesis, Aplasia, and Hypoplasia: Causes, Diagnosis, and Treatment

Pulmonary Agenesis, Aplasia, and Hypoplasia: Causes, Diagnosis, and Treatment

pediagenosis    October 05, 2026   

Pulmonary Agenesis, Aplasia, and Hypoplasia

Three different degrees of arrested development of the lungs may occur: (1) agenesis, in which there is a complete absence of one lung or both lungs and no trace of bronchial or vascular supply or parenchymal tissue; (2) aplasia, in which there is a suppression of all but a rudimentary bronchus ending in a blind pouch and there are no pulmonary vessels and no parenchyma; and (3) hypoplasia, in which there is incomplete development of the lung, which is smaller in weight and volume, and there is a reduced number of airways branches, alveoli, arteries, and veins.

Nephrotic Syndrome: Causes, Symptoms, Diagnosis, Pathophysiology and Treatment

Nephrotic Syndrome: Causes, Symptoms, Diagnosis, Pathophysiology and Treatment

pediagenosis    October 04, 2026   

Overview Of Nephrotic Syndrome

The nephrotic syndrome encompasses a constellation of clinical and laboratory findings related to the loss of large quantities of protein in urine. The major symptom is edema, and the laboratory findings include (1) “nephrotic-range” proteinuria, defined in adults as more than 3.5 g of protein excretion per 24 hours, (2) hypoalbuminemia, and (3) hyperlipidemia. The thresh old for nephrotic proteinuria in children is lower and depends on body weight.

Skin Embryology: Development of the Epidermis, Dermis, Hair and Nails

Skin Embryology: Development of the Epidermis, Dermis, Hair and Nails

pediagenosis    October 03, 2026    Comment   

Embryology Of The Skin.

The human skin develops from two special embryonic tissues, the ectoderm and the mesoderm. Epidermal tissue is derived from the embryonic ectoderm. The dermis and subcutaneous tissue are derived from the embryonic mesoderm. The developmental interactions between mesoderm and ectoderm ultimately determine the nature of human skin. Interestingly, neural tissue and epidermal tissue are both derived from the ectoderm. It is believed that calcium signaling is critical in determining the fate of the ectoderm and its differentiation into either epidermis or neural tissue.

Thorax Anatomy: Thoracic Cage, Lungs, Mediastinum, Heart & Major Structures

Thorax Anatomy: Thoracic Cage, Lungs, Mediastinum, Heart & Major Structures

pediagenosis    October 02, 2026    Comment   

LUNGS IN SITU: ANTERIOR VIEW

        Thorax

Before describing the anatomy of the heart, it is helpful to review other anatomic features of the thoracic cavity and organs. The thorax proper constitutes the upper part of the body or trunk, with a shape between a barrel and a truncated cone that is functionally favorable. Although the intrathoracic pressure is often subatmospheric, the chest wall is still able to retain its integrity by means of rather thin, lightweight skeletal elements. The thoracic cavity occupies only the upper part of the thoracic cage. The abdominal (peritoneal) cavity reaches upward as high as the lower tip of the sternum, affording protection to large, easily injured abdominal organs such as the liver, spleen, stomach, and kidneys.

Granuloma Inguinale (Donovanosis): Symptoms, Diagnosis & Treatment

Granuloma Inguinale (Donovanosis): Symptoms, Diagnosis & Treatment

pediagenosis    October 01, 2026   

GRANULOMA INGUINALE

Granuloma inguinale (also known as “Donovanosis”) is a sexually transmitted bacterial infection of endemic proportions in many underdeveloped countries. The pathognomic feature of the disease are Donovan bodies on Giemsa or Wright stain, intracellular inclusions representing the causative gram negative Klebsiella granulomatis bacteria that have been engulfed by mononuclear phagocytes. Clinically, granuloma inguinale is characterized by painless genital ulcers that appear 10 to 40 days after contact and that can be mistaken for syphilis. However, unlike syphilis, they can progress to mutilate and destroy tissue and are often superinfected with other pathogenic organisms. The lesions occur in the region of contact, which is typically the penile shaft or perineum, and contain Donovan bodies when the superficial layers of the ulcer are scraped or when stained granulation tissue is examined.

Thoracolumbar and Sacral Spine Anatomy: Vertebrae, Discs & Ligaments

Thoracolumbar and Sacral Spine Anatomy: Vertebrae, Discs & Ligaments

pediagenosis    September 30, 2026    Comment   

THORACIC VERTEBRAE AND LIGAMENTS

ANATOMY OF THE THORACOLUMBAR AND SACRAL SPINE

THORACIC VERTEBRAE AND LIGAMENTS

The 12 thoracic vertebrae (T1 to T12) are intermediate in size between the smaller cervical and the larger lumbar vertebrae. The heart-shaped vertebral bodies are slightly taller posteriorly than anteriorly, producing a slight wedge shape (see Plate 1-17). Vertebrae are easily recognized by their costal facets on both sides of the bodies and on all the transverse processes except those of T11 and T12. The costal facets articulate with the facets on the heads and tubercles of the corresponding ribs. The spinal canal is smaller and more rounded than in the cervical spine and corresponds to the more circular shape of the spinal cord in the thoracic region. The spinal canal is formed by the posterior surfaces of the vertebral bodies and by the pedicles and laminae forming the vertebral arches. The stout pedicles are directed posteriorly; they have shallow superior and much deeper inferior vertebral notches. The laminae are short and relatively thick and partially overlap each other from above downward.