MRI
Staging of colorectal cancer
TNM classification of colorectal cancer
| T | Primary tumor |
|---|---|
| Tx | Primary tumor cannot be assessed |
| T0 | No evidence of primary tumor |
| Tis | Carcinoma in situ: invasion up to lamina propria mucosae |
| T1 | Tumor invades submucosa |
| T2 |
Malrotation of the gut
During development, the bowel rotates 270° anticlockwise in two locations: the foregut and midgut junction (duodenum) and midgut-hindgut location (cecum), so that the ligament of Treitz is located left to the midline and cecum reaches the right iliac fossa. Completeness of rotation can be classified into four cathegories:
| Cathegory | Description |
|---|---|
| Normal rotation | Normal appearance of the gut, cecum in the right iliac fossa and the ligament of Treitz left to the midline |
Subependymal hemorrhage (SEH) into germinal matrix
Subependymal hemorrhage or germinal matrix hemorrhage occurs in premature infants with very low birth weight (<1500g). The germinal matrix in the immature brain is located around the lateral ventricles and it contains a fine network of fragile blood vessels, which are sensitive to ischemia and changes in perfusion pressure. Subependymal hemorrhage in premature neonates can be easily assessed by ultrasound and be divided into four grades.
| Grade | Description |
|---|---|
| Grade I | hemorrhage confined to the germinal matrix |
| Grade II | intraventricular hemorrhage (hemocephalus) without ventricular dilation |
| Grade III | intraventricular hemorrhage (hemocephalus) with ventricular dilation |
| Grade IV | intraventricular rupture with hemorrhage into the surrounding white matter |
References:
1. Bowerman R, Donn S, Silver T, Jaffe M. Natural history of neonatal periventricular/intraventricular hemorrhage and its complications: sonographic observations. American Journal of Roentgenology. 1984 Nov 1;143(5):1041–52.
2. Radack DM, Baumgart S, Gross GW. Subependymal (grade 1) intracranial hemorrhage in neonates on extracorporeal membrane oxygenation. Frequency and patterns of evolution. Clin Pediatr (Phila). 1994 Oct;33(10):583–7.
3. Smith WL, McGuinness G, Cavanaugh D, Courtney S. Ultrasound screening of premature infants: longitudinal follow-up of intracranial hemorrhage. Radiology. 1983 May 1;147(2):445–8.
Estimate of spleen volume on CT or MRI, splenic index - calculator
This formula can be used to estimate volume of the spleen on crossectional imaging methods by measuring three dimensions - caudocranial (L), maximum size in axial plane (D), and maximum thickness in axial plane (T).
Splenic index = L x D x T
A normal value is considered ≤480.
Volume [mL] = 30 + 0.58 x L x D x T
A normal value is considered between 110 and 340mL
Dislocation in acromioclavicular joint - Rockwood classification of AC dislocation
Rockwood classification divides dislocations in AC joint into six grades. It is an extension of the previous classification by Tossy et al. Normal width of AC joint is considered 1-3mm, widened AC joint has >7mm in men or >6mm in women.
| Grade | Description |
|---|---|
| Grade I | sprain of the acromioclavicular (AC) ligaments |
| Grade II | complete rupture of the AC ligaments |
| Grade III |
Dislocation in acromioclavicular joint - Tossy classification of AC dislocation
Tossy classification divides dislocations in AC joint into three grades. It was later extended by Rockwood et al. by another three types. Normal width of AC joint is considered 1-3mm, widened AC joint has >7mm in men or >6mm in women.
| Grade | Description |
|---|---|
| Grade I | no deformity visible on x-ray - strain and contusion of the AC joint |
| Grade II |
Lesion of labrum glenoidale - Snyder classification of labral lesions (SLAP)
The classification of lesions of labrum glenoidale was published by Snyder et al. and had originally four types. Later, several authors added descriptions of other labral lesions.
| Type | Description |
|---|---|
| Type I | fraying |
| Type II | tear with biceps extension |
| Type III | bucket-handle tear with intact biceps |
| Type IV | bucket-handle tear with biceps extension |
Prostatic cancer - types of invasion into seminal vesicles
Researches at the Baylor College of Medicine identified and defined three types of invasion of prostatic cancer into seminal vesicles.
| Type | Description |
|---|---|
| Type I | direct spread of prostate cancer along the ejaculatory duct complex into the seminal vesicles |
| Type II | invasion through the prostatic capsule into the seminal vesicles
|
Estimate of liver volume on CT or MRI - calculator
This formula can be used to estimate volume of the liver on crossectional imaging methods by measuring its maximum dimension in three perpendicular axes - caudocranial (CC), latero-lateral (LL), antero-posterior (AP). A normal value is considered <2000mL.
Volume = CC x LL x AP x 0.31
Subarachnoid hemorrhage - Fisher CT grading scale of subarachnoid bleeding
Fisher CT grading scale is used to grade severity of intracranial subarachnoid hemorrhage associated with rupture of an intracranial aneurysm. This scale predicts the risk of subsequent arterial spasms.
| Group | Description |
|---|---|
| Group I | no hemorrhage |
| Group II | subarachnoid hemorrhage <1mm thick |
| Group III | subarachnoid hemorrhage >=1mm thick |
| Group IV |
