Radiology References

Imaging atlases, normal values, and reporting templates.

302 references · Page 5 of 11

I

Normal Intercarpal Joint Space Size on Radiography
Normal intercarpal joint space measures 1.5–2.0 mm on PA and lateral radiographs — a key reference for detecting carpal instability and arthritis.
Normal Intermetatarsal Angle Size on Radiography
Normal intermetatarsal angle values on AP radiography: <9° for 1st–2nd and <8° for 4th–5th metatarsals in foot alignment assessment.
Normal Internal Auditory Canal Size on CT and MRI
Normal internal auditory canal diameter measures 4–8 mm on axial CT and MRI; values below 2 mm indicate stenosis with clinical significance.
Normal Internal Carotid Artery Diameter on Angiography
Normal internal carotid artery diameter values by segment on angiography, from the cervical to clinoid segment, based on established reference data.
Normal Internal Carotid Artery Stenosis Grading on Ultrasound
Learn the Society of Radiologists in Ultrasound consensus criteria for grading internal carotid artery stenosis by Doppler ultrasound, including PSV, EDV, and ICA/CCA ratios.
Normal Interphalangeal Joint Space Size on Radiography
Normal interphalangeal joint space of the foot measures 1–2 mm on radiography; deviations indicate arthritis or injury requiring clinical correlation.
Normal Interphalangeal Joint Space Size on Radiography
Normal interphalangeal joint space measures 1–2 mm on PA and lateral radiographs; deviations indicate arthritis, injury, or effusion.
Normal Intertarsal Joint Space Size on Radiography
Normal intertarsal joint space measures 2.0–2.5 mm on radiography; deviations may indicate arthritis, ligamentous injury, or coalition.
Normal Intrahepatic Duct Size on Ultrasound, CT & MRI
Normal intrahepatic bile ducts measure less than 2 mm in diameter; values exceeding this threshold suggest biliary dilatation requiring clinical correlation.

J

Normal Johnson Angle Size on Radiography: Foot & Ankle
The normal Johnson angle measures 92° on AP mortise radiography, a key reference for assessing tibiotalar alignment and ankle pathology.

K

Normal Kager's Triangle Size on Radiography
Learn the normal radiographic appearance of Kager's triangle, a key fat-pad space on lateral ankle X-ray used to detect Achilles tendon pathology.
Normal Kidney Cortex Thickness on Ultrasound and CT
Normal renal cortex thickness ranges from 2.6–10.6 mm on CT and ultrasound; learn measurement technique, clinical thresholds, and key pathologies.
Normal Kidney Diameter Size on Ultrasound, CT & MRI
Normal kidney diameter ranges 9–13.5 cm depending on side; learn measurement thresholds across ultrasound, CT, and MRI for clinical practice.
Normal Kidney Parenchyma Thickness on Ultrasound & CT
Normal renal parenchymal thickness ranges 9.8–21.2 mm on CT and ultrasound; learn measurement technique and clinical thresholds for abnormal findings.
Normal Kidney Size Discrepancy: Ultrasound & CT Reference
Normal maximal diameter discrepancy between left and right kidneys is ≤1.5 cm on ultrasound and CT, per large MDCT reference data.
Normal Klaus Index Size on X-ray, CT & MRI
The normal Klaus Index measures >30 mm on lateral cervical imaging, helping clinicians detect basilar invagination on X-ray, CT, and MRI.
Normal Knee Joint Space Width on Radiography and MRI
Normal knee joint space width measures 3–5 mm on anteroposterior radiography, a key threshold for detecting cartilage loss and osteoarthritis.

L

Normal Lateral Acetabular Inclination Angle Size Radiography
Normal lateral acetabular inclination angle on AP radiography ranges 30–50°, a key measure for assessing hip joint congruency and stability.
Normal Lateral Recess Height Size on CT and MRI
Normal lateral recess height measures greater than 2 mm on CT and MRI; values at or below this threshold indicate stenosis requiring clinical correlation.
Normal Lateral Trochlear Inclination Size on MRI
Normal lateral trochlear inclination on MRI measures greater than 11°, a key threshold for assessing patellar instability and trochlear dysplasia.
Normal Lateral Ventricle Size on Ultrasound
Normal lateral ventricle measurements on cranial ultrasound, including body and frontal horn dimensions, with clinical thresholds for ventriculomegaly.
Normal Left Atrium Diameter Size on Radiography
Normal left atrium diameter on posteroanterior chest radiography measures less than 7 cm, a key threshold for detecting left atrial enlargement.
Normal Left Gastric Vein Diameter: Ultrasound Reference
Normal left gastric vein diameter is less than 6 mm on color Doppler ultrasound; enlargement is a key marker of portal hypertension and variceal risk.
Normal Left Pulmonary Artery Size on Chest Radiography
Normal left pulmonary artery diameter is less than 18 mm on lateral chest radiography, a key threshold for detecting pulmonary arterial enlargement.
Normal Left Pulmonary Artery Size on Chest X-Ray
Normal left pulmonary artery diameter on chest radiography measures up to 18 mm on the lateral view, a key threshold for detecting pulmonary hypertension.
Normal Liver Diameter Size by Age: Ultrasound, CT & MRI
Reference guide for normal liver diameter measured in the midclavicular line across all age groups on ultrasound, CT, and MRI imaging.
Normal Liver Segments Anatomy on Ultrasound
A concise ultrasound reference for normal liver segment anatomy based on the Couinaud classification, essential for lesion localization and surgical planning.
Normal Lumbosacral Angle Size on X-ray, CT & MRI
The normal lumbosacral angle measures 26–57° on lateral imaging; deviations correlate with low back pain, spondylolisthesis, and altered spinal biomechanics.
Normal Lumbosacral Disc Angle Size on X-ray, CT & MRI
The normal lumbosacral disc angle measures 10–15° on lateral imaging; deviations may indicate spondylolisthesis, disc pathology, or postural malalignment.
Normal Lunotriquetral Angle Size on Radiography
The normal lunotriquetral angle measures 14° on lateral radiography, a key reference for diagnosing carpal instability and ligamentous injury.