A broad spectrum of congenital anomalies and pathologic conditions can affect the inferior vena cava (IVC). Most congenital anomalies are asymptomatic; consequently, an awareness of their existence and imaging appearances is necessary to avoid misinterpretation. Imaging also plays a central role in the diagnosis of Budd-Chiari syndrome secondary to membranous obstruction of the intrahepatic IVC. Primary malignancy of the IVC is far less common than intracaval extension of malignant tumors arising in adjacent organs, and imaging can accurately help determine the presence and extent of tumor thrombus, information that is crucial for surgical planning. However, the radiologist should be aware that artifactual filling defects at computed tomography and magnetic resonance imaging can mimic true thrombus in the IVC and must be able to differentiate true from pseudo filling defects. Other imaging findings such as flat IVC and early enhancement of the IVC are useful in limiting the differential diagnosis. Familiarity with the imaging features of the various congenital and pathologic entities that can affect the IVC is paramount for early diagnosis and management.

Respiratory-triggered DWI should be preferred over breath-hold DWI for the evaluation of focal liver lesions because it provides better image quality and SNR without any compromise in the calculated ADC values.

The results of this study indicate that GCT of bone may show raised choline levels on proton MR spectroscopy. This finding is not an indicator of malignancy in these tumors.

ABSTRACT. Sciatic hernia is a rare condition with diverse clinical manifestations. We report a case of sciatic hernia causing sciatica, in which the diagnosis made on CT was subsequently confirmed on MRI including magnetic resonance neurography. The salient clinical and imaging features and a brief review are presented. Sciatic hernia is a rare condition that can lead to bowel obstruction, sciatica, pelvic pain, back pain or ureteric obstruction [1,2]. Clinical diagnosis of this condition is difficult. Ultrasonography and CT are the imaging modalities commonly used to diagnose sciatic hernia, although MRI can be used in cases in which entrapment of the sciatic nerve is suspected. Magnetic resonance neurography (MRN) provides high-resolution images to demonstrate entrapment of the nerve and morphological changes in the nerve [3]. Colour Doppler can be useful in surgical planning, as it can provide information regarding bowel viability. Case reportA 55-year-old woman presented with swelling in the left gluteal region and pain in the left lower limb of two years' duration. A detailed clinical history also revealed that she had an abscess in the left gluteal region following an intramuscular injection one year previously; however, at presentation there was no clinical feature suggestive of abscess. Physical examination revealed non-tender soft swelling in the left lumbar region with associated atrophy of gluteal muscles. To diagnose the nature of the gluteal mass, a CT scan of the pelvis and gluteal region was performed. The CT scan revealed herniation of the sigmoid colon through the greater sciatic foramen reaching up to the skin surface and atrophy of the gluteal muscles. Other major pelvic organs including the uterus, ureter and urinary bladder were normally located ( Figure 1). As there was atrophy of the left gluteal muscles, and because the patient had symptoms of sciatica, entrapment of the sciatic nerve by sciatic hernia was suspected. MRI of the pelvis and upper thigh with MRN was performed to confirm entrapment of the sciatic nerve. MRN was used for high-resolution imaging of the sciatic nerve and was performed on a 1.5 T scanner (Sonata, Siemens, Erlangen, Germany) using a pelvis phase-array coil. Sequence parameters included 4 mm section thickness, 0 mm intersection gap, 18-24 cm field of view, 256 6 256 matrix, and an 8-to 10 min imaging time per sequence. The patient underwent axial T 1 weighted spin echo (580/11/2-3 [TR/TE/excitations]) and axial and oblique coronal short tau inversion recovery (STIR, 5000/27/2-3; inversion time, 130 ms) sequences. Coronal oblique images were taken parallel to the course of the sciatic nerve. MRI revealed thickening and increased signal in the left sciatic nerve on STIR coronal oblique images (Figure 2). Lateral deviation and entrapment of the nerve by hernia was also noted along with atrophy of the left gluteal muscles.

Large bowel haemangiomas are rare but can cause significant morbidity. The clinical features are non-specific, and misdiagnosis is very common. Non-invasive imaging is very useful in the diagnosis and management of this condition. Magnetic resonance imaging surpasses all other imaging modalities, as it is most specific and depicts the extent of the lesion accurately. Two cases of cavernous haemangioma of the rectum are presented highlighting the MRI features.