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ILEAL VESSELS: Branches of the Superior Mesenteric Artery (SMA) that form the vascular supply to the "ileum" or distal portion of the small intestine. image image

ILEOCECAL VALVE: The valve-like structure formed by the flaps of the ileocecal opening. May prevent reflux of colonic contents into the small intestine. image

ILEOCOLIC ARTERY: The artery which originates from the superior mesenteric and branches into the anterior and posterior cecal, appendicular, colic, and ileal rami arteries. image

ILIAC CREST: The arching ridge of bone on the upper border of the ilium. image

ILIAC LYMPH NODES: Lymph nodes situated along the iliac vessels. image

ILIACUS MUSCLE: Muscle that originates at the iliac fossa and base of the sacrum, and inserts into the lesser trochanter of the femur. It contributes to the flexion of the thigh and trunk against the lower limb.

ILIOLUMBAR ARTERY: Artery which originates from the internal iliac and branches into the iliac and lumbar branches and lateral sacral arteries. image

ILIOPSOAS MUSCLE: A compound muscle made up of the iliacus and psoas muscles, a flexor of the hip, inserts onto the lesser trochanter of the proximal femur. The psoas arises along the lateral border of the lumbar spine. image

ILIUM: The superior portion of the hip or pelvic bone. image

INCUS: The middle ossicle of the ear, that helps to conduct vibrations from the tympanic membrane to the oval window of the inner ear. Together, the incus and malleus look like an ice cream cone. image

INFERIOR GLUTEAL ARTERY: The artery which originates from the internal iliac and branches into the sciatic artery. image

INFERIOR (TEMPORAL) HORN: The portion of the lateral ventricle which stretches from the pars centralis, behind the thalamus, into the temporal lobe. image

INFERIOR MESENTERIC ARTERY: Artery which originates from the abdominal aorta and branches into the left colic, sigmoid, and superior rectal arteries.

INFERIOR MESENTERIC VEIN: The vein that parallels the inferior mesenteric artery and drains into the splenic vein. image

INFERIOR ORBITAL FISSURE: Located in the inferolateral wall of the orbit, it allows for the passage of the infraorbital and zygomatic nerves and infraorbital vessels. It is surrounded by the greater wing of the sphenoid and the orbital process of the maxilla. image

INFERIOR PUBIC RAMUS: Portion of the pubic bone which projects posteroinferolaterally to join the ramus of the ischium. image

INFERIOR VENA CAVA: The vein that begins at the junction of the two common iliac veins, at the level of the fifth lumbar vertebra, and empties into the right atrium. It drains blood from the lower extremities, and the pelvic and abdominal viscera.
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INFRASPINATUS MUSCLE: Muscle responsible for the lateral rotation of the humerus. It originates from below the scapula spine (infraspinous fossa) and inserts onto the greater tubercle of the humerus. image

INNER TABLE OF SKULL: The inner layer of compact bone of the flat bones of the skull. The periosteal layer of the dura is attached to the inner table. image

INGUINAL LYMPH NODES: Lymph nodes situated along the inguinal vessels. image

INTERCONDYLAR EMINENCES: A projection on the proximal end of the tibia, set in between two tubercles. image image image

INTERHEMISPHERIC FISSURE: The cleft between the two cerebral hemispheres, containing CSF and the falx cerebri. image

INTERNAL AUDITORY MEATUS: The channel that allows for the passaage of the facial, intermediate, and vestibulocochlear nerves, and the labrynthine artery to pass. image

INTERNAL ILIAC ARTERY: Artery which is a continuation of the common iliac and branches into the iliolumbar, obturator, superior gluteal, inferior gluteal, umbilical, inferior vesicle, uterine, middle rectal, and internal pudendal arteries. image

INTERNAL ILIAC VEIN: The vein originating from the parietal branches at the level of the greater sciatic notch, and extends to the brim of the pelvis where it joins the external iliac to form the common iliac vein. image

INTERNAL OBLIQUE MUSCLE: Muscles which originates at the inguinal ligamen, iliac crest, and lumbar aponeurosis, and inserts into the lower three or four costal cartilages, the linea alba, and the conjoined tendon to the pubis. It is responsible for flexion and rotation of the vertebral column and compression of the abdominal viscera. image

INTERNAL THORACIC ARTERY: Artery which orginates from the subclavian, and branches into the mediastinal, thymic, bronchial, tracheal, sternal, perforating, medial mammary, lateral musculophrenic, and superior epigastric arteries. image

INTERNAL THORACIC VEINS: The two veins created from the junction of the venae comitantes of the internal thoracic arteries, and empties into the brachiocephalic vein. image

INTERTROCHANTERIC LINE: The line that extends obliquely downward from the superior tubercle and then around the medial side of the femur, between the greater and lesser trochanter. image image image

INTERVENTRICULAR SEPTUM: The musculomembreanous division that separates the left ventricle from the right ventricle of the heart.

INTERVERTEBRAL DISC SPACE: The space between the vertebrae, formed from a fibrous ring (the annulus) and a central "cushion" (nucleus pulposis). image image image

ISCHIAL SPINE: Process of bone projecting from the posterior border of the ischium, at the level of the lower border of the acetabulum, backward and medially. image

ISCHIAL TUBEROSITY: Elongated projection on the inferoposterior margin of the body of the ischial bone, that serves as the point of attachment for a number of muscles. image

ISCHIORECTAL FOSSA: The space between the pelvic diaphragm and the skin below it. The fat in this region is almost a liquid at body temperature, allowing for changes in the size and shape of the rectum. image

ISCHIUM: The inferior dorsal portion of the hip bone. image

IVP - Intra Venous Pyelogram: An imaging study to look at the structure and function of the kidneys, ureters, and bladder. Also called an IVU - intravenous urogram. This test requires the injection of a *contrast agent*. external link


Bug Report
Portions © 1997, 2002 J.G. Smirniotopoulos, M.D. and others.