This document outlines an MRI study protocol for evaluating the pelvic floor. It involves filling the rectum with ultrasound gel and obtaining static and dynamic sagittal T2 weighted images at rest, during sustained contraction, Valsalva maneuver, and defecation. This allows evaluation of pelvic floor morphology and function to identify issues like prolapse or intussusception. Fasting is not required but a laxative is given beforehand to empty the bowels.

1. BY : DR.CHANDNI WADHWANI
Resident doctor
Department of Radiology
Medical College Baroda,
SSG Hospital Vadodara, Gujarat , India.

4.  Multicystic masses of segmental lung tissue
with abnormal bronchial proliferation.
 Part of the spectrum of bronchopulmonary
foregut malformations
 Previously called, Congenital cystic
adenomatoid malformations (CCAM).

5.  Type I and II CPAMs demonstrate a multicystic
(air-filled) lesion.
 Large lesions may cause a mass effect with
resultant mediastinal shift, depression, and
even inversion of the diaphragm.
 In the early neonatal period, the cysts may be
completely or partially fluid-filled, in which case
the lesion may appear solid or with air-fluid
levels.
 Lesions may change in size on interval imaging
expand from collateral ventilation via pores of
Kohn.
 Type III lesions appear solid.

9.  The end result of the aseptic separation of an
osteochondral fragment with the gradual
fragmentation of the articular surface.
 It is often associated with intraarticular loose
bodies.
 Spontaneous healing is usual unless there is an
unstable fragment.
 Signs of instability include large size (>1cm),
cyst-like lesions beneath a fragment, contrast
beneath a fragment on contrast arthrography,
and loose body.
 OCD may be bilateral in 20-25% of cases.

12.  Cholecystopathia chronica calcarea
 Seen in the 60s in a female (M:F = 1:5)
 Often an incidental detection, the importance
lies in early removal of gall bladder as 33% of
porcelain gall bladder tends to turn malignant
 Supersaturated bile, intra mural hemorrhage
and/or dystrophic calcification are the described
mechanisms
 Loss of wall echo shadow sign (double arc
shadow) is typical for porcelain GB on
ultrasound

16.  Gas forming infection of the bladder wall.
 Bacterial or fungal infection, most common E.
coli.
 CT
 highly sensitive examination that allows early
detection of intraluminal or intramural gas.
 evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel
carcinoma or inflammatory disease.
 Complications
 bladder rupture with septicemia and peritonitis

18.  MC non-neoplastic fibrous bone lesions
 A larger version (>3 cm) of a fibrous cortical
defect; both are encompassed by the
term fibroxanthoma or metaphyseal fibrous
defect.
 “Don’t touch” lesion
 no treatment and no biopsy.
 If large (involving more than 50% of the
diameter of the parent bone) then prophylactic
curettage and bone grafting may be prudent to
avoid a pathological fracture

20.  Unilocular well defined pericoronal radiolucencies centred on an
impacted or unerupted tooth.
 They have a thin regular sclerotic margin and expand the
overlying cortex without cortical breach (unless superimposed
fracture or infection).
 Their size is extremely variable, ranging from only slightly greater
in size than a normal follicle to very large, appearing to hollow-out
the majority of the jaw.
 Erosion or resorption of the roots of adjacent teeth is sometimes
seen
 Complications
 Pathological jaw fracture, if large
 Mural ameloblastoma
 Squamous cell carcinoma in the context of chronic infection

21.  When small, it is difficult to differentiate a
dentigerous cyst from a large but normal dental
follicle .
 When larger, the differential includes:
1. periapical cyst (radicular cyst)
2. aneurysmal bone cyst (ABC)
3. ameloblastoma
4. odontogenic keratocyst
5. cherubism (fibrous dysplasia)

23.  perineural cysts
 CSF filled dilatations of the nerve root sheath at
the dorsal root ganglion (posterior nerve root
sheath). These are type II spinal meningeal
cysts that are, by definition, extradural but
contain neural tissue.
 incidentally found and are asymptomatic.
 In some , perineal pain/discomfort or lower back
pain or sphincter/sexual dysfunction .
 Large cysts may cause local pressure effect
and remodel bones.

24.  Type I: extradural meningeal
cyst without neural tissue
› type Ia: extradural spinal arachnoid cyst
› type Ib: sacral meningocele
 type II: extradural meningeal
cyst containing neural tissue, e.g. Tarlov
cyst
 type III: intradural spinal arachnoid cyst

26.  Arise from nerves within the spinal canal.
 Mc intradural extramedullary spinal tumour(30%)
 MC :the cervical and lumbar regions
 Rounded lesions -associated adjacent bony remodelling.
 Frequently associated with haemorrhage, intrinsic
vascular changes (thrombosis, sinusoidal dilatation), cyst
formation and fatty degeneration(vs neurofibroma)
 With NF2, there is a high incidence of new tumour
formation.
 Debilitating; never undergo malignant change
 Surgery.

28.  MRI demonstrates complete replacement of
normal bone marrow signal within the entire
L5 vertebral body (including posterior
elements) with enhancing soft tissue
compressing the cauda equina.
 Radiotherapy is the primary therapy for
potential preservation of neurologic function
and extension of survival

30.  Hypervascular appearance of the mesentery in
active crohn disease.
 Fibrofatty proliferation and perivascular inflammatory
infiltration outline the distended intestinal arcades.
 This forms linear densities on the mesenteric side of the
affected segments of small bowel, which give the
appearance of the teeth of a comb.
 Also in other acute inflammatory conditions of bowel
and lupus mesentric vasculitis.
 Used to differentiate active inflammatory condition from
lymphoma and metastases, which tend to be
hypovascular.

32.  A thrombosed subcutaneous vein.
 The patients can complain of pain but
usually the abnormaility is paplable and felt
by the patient.
 The key is to add ultrasound regardless of
the mammographic findings.
 A high clinical suspicion will make the
diagnosis together with the Doppler
ultrasound images.

34.  Black “lightning” marks represent static
electricity artefacts
 This occurs due to films being forcibly
unwrapped or due to excessive flexing of film

36.  large disk-shaped tungsten anode is rotated at high
speed (3000 to 9000 revolutions per minute).
 The motive force provided by an induction motor the
windings of which are housed outside the tube.
 Although the focal spot of the electrons impinging on
the anode is no larger than that in a tube with a
stationary anode, the effective area of the anode
exposed to the beam is much larger.
 By this means, the heating of the anode is reduced and
the tube loading can be increased (e.g., up to 500 mA
with a 2 mm x 2 mm focal spot).

38.  The appearance of the ureter when it is focally
dilated by an intraluminal mass.
 It is best seen when the ureter is opacified from
below, by a retrograde ureterogram.
 Indicates the pathology to be chronic, permitting
the lesion to be accommodated in the ureter.
 Also in:
 Metastatic disease into the ureter
 Endometriosis involving the ureter
 A stone filling defect will cause upstream
dilatation usually and downstream narrowing
due to spasm and oedema

40.  well-defined, hypoechoic lesion in superficial lobe of left
parotid gland.
 There is no calcification / cystic changes / flow signals in
lesion.
 There is posterior acoustic enhancement.
 Rest of the gland shows normal echopattern without
dilated ducts / other lesions.
 There is a small risk of malignant transformation into
a carcinoma ex-pleomorphic adenoma proportional to the
time the lesion is in situ (1.5% in first 5 years, 9.5% after
15 years).
 excision is recommended in essentially all cases.
 Additional risk factors for malignancy include advanced
age, large size, radiation therapy and recurrent tumours

42.  Right knee x-ray revealed femoral and tibial
metaphyseal sclerosis.
 Lung HRCT showed predominantly cystic mid
and upper zone disease with interstitial
thickening, a few nodules and preservation of
lung volumes.
 cardiomegaly and pleural effusions that do
not respond to diuretics
 non-Langerhans cell, non-familial multisystemic
granulomatosis,

43.  widespread manifestations
 The most common presenting symptom is
bone pain.
 Patients may also present with focal
neurological
signs, exophthalmos, retroperitoneal fibrosis,
diabetes insipidus, and dyspnoea due to
extra-skeletal involvement of these systems.

44.  Symmetrical metaphyseal sclerosis and
corresponding increased uptake on Tc-MDP
bone scan.

46.  MRI artifact which occurs on sequences with a
short TE(less than 32ms; T1W sequences, PD
sequences and gradient echo sequences).
 It is confined to regions of tightly bound collagen at 54.74°
from the main magnetic field (B0), and appears
hyperintense, thus potentially being mistaken
for tendinopathy.
 It appears that at 3.0T the effects are reduced.
 Other non-pathologic causes of high signal within
tendons include near tendon insertions, and/or where the
tendon normally fans out or merges with other tendons.
 Tends to occur only on short TE sequences (e.g. T1, GRE,
PD), sequences with a longer TE (e.g. T2 including FSE
T2) can be used to avoid this artifact.

49.  STUDY PROTOCOL
 Use of a laxative agent 24 hours before the procedure.
 Fasting is not necessary.
 The bladder may be partially empty.
 MRI 1.5 T close field GE MR 450.
 The rectum must be filled with 180-250 ml of ultrasound gel; at our institution we have obtained
good results without using gel mixtures with gadolinium described by other authors.
 The patient must be in anterior supine position, with both knees flexed and with an adult diaper.

 The first step is to obtain simple static images to study the morphology of the pelvic floor in
coronal, sagittal and axial T2 weighted images.

 The second step is to obtain fast dynamic sagittal sequences in T2 with video:
 - At rest.
 - Sustained contraction.
 - Valsalva.
 - During defecation.
 In some cases a series of images at post defecation phase are required to evaluate the
possibility of intussusception.