Putty kidney

43 year old female came for USG evaluation of abdomen to rule out metastasis from carcinoma breast. This USG showing calcified mass in whole of the left kidney witch is maintaining the renal contour with posterior acoustic shadow suggestive of putty kidney.

Putty kidney is an end stage of infection with tuberculosis in the genitourinary tract, calcification may entirely outline a nonfunctional kidney.The radiologic appearance of this condition, completely calcified kidney which is associated with autonephrectomy, has been described as the putty kidney. It is very common to see the radiographic and CT appearance of putty kidney but unusual to see the USG features of putty kidney.

Osteosarcoma of Sternum

CT scan and MRI of 40 year old male came with swelling and pain in the sternum since 3 months shows large destructive soft tissue mass lesion in the body of sternum having osteoid matrix. The lesion is extending anteriorly in the subcutanesous region, psoteriorly in to mediastinum abutting large vessels. We can better appreciate the sternal destruction in SSD image. MR T2 weighted image shows hyperintense signal throughout the lesion. Histopathology proved to be osteosarcoma.

The primary sternal tumors are quite rare. The most commonly occurring malignant tumor in sternum is chondrosarcoma and occurrence of osteosarcoma in sternum is extremely rare. The most common tumors of sternum are the metastases of lung, renal or thyroidal malignancies. CT may show lytic, mixed or sclerotic pattern and it is observed as an expansile mass lesion with irregular borders, and the lesion invades bone marrow by destroying the cortex. MRI clearly demonstrates the extent of the lesion and characterization of the lesion.

Occular Metallic Foreign body

17 year old male CT coronal, axial and coronal bone window showing metallinc foreign body in the right globe adherent to lateral wall.
Metallic foreign body in another patient in right orbit on radiograph (arrow). CT scan axial section of the same patient showing foreign body just posterior to the limbus which is extra occular.

Intraocular foreign bodies (IOFBs) are rather variable in presentation, outcome, and prognosis. With increased awareness and advanced surgical techniques, the outcome and the prognosis for these potentially devastating injuries have substantially improved.

CT scans are the imaging study of choice for IOFB localization. A helical CT scan is the most efficient method to establish a diagnosis. Helical CT scans have a very high identification rate. With conventional CT scans, cuts of 0.5 mm are advised. With the advent of MDCT the role of radiologist has become easier in identification and diagnosis of occular foreign body. Plain x-ray is useful if a metallic IOFB is present and a CT scan is unavailable. MRI is generally not recommended for metallic IOFBs. Ultrasound is a useful tool in localizing IOFBs, and its careful use is possible even if the globe is still open; alternatively, intraoperative use after wound closure can be attempted. The ultrasound biomicroscope may help with IOFBs in the anterior segment.

Pheochromocytoma

MRI abdomen of 14 year old male patient came with uncontrolled hypertension with raised urinary catecholamines showing well defined focal soft tissue intensity mass in the left supra renal gland having intensely hyperintense on T2 W image and hypointense on T1W image. Features are consistent with pheochromocytoma.

Pheochromocytomas are rare but treacherous catecholamine-producing tumors, which if missed or not properly treated, will almost invariably prove fatal. Prompt diagnosis is, therefore, essential for effective treatment, usually by surgical resection. The manifestations are diverse and the tumor can mimic a variety of conditions, often resulting in either erroneous diagnoses or a delayed diagnosis. Imaging is very essential for accurate diagnosis.

Pheochromocytomas are extra adrenal (10%), multicentric (10%), bilateral (5%), and malignant (10%)..Size is variable from 1-20 cm.The treatment is surgical excision of tumor, which is curative in all cases. The initial imaging findings in benign and malignant pheochromocytomas are nearly identical. Only the presence of metastasis can clearly define a lesion as malignant. On CT it appears as round or oval discrete mass with homogenous density. Similar findings have been noted in the present case. Central necrosis, calcification and cystic changes may be present in minority of cases. These vascular lesions enhance uniformly after administration of contrast material. MR is also excellent for evaluating intraadrenal pheochromocytoma.On T1, mass has intensity similar to or slightly less than solid organs. OnT2 lesion is hyper intense as result of their long T2 time. Sometimes adrenal metastases also present overlapping imaging findings. Combination of MIBG,CT and MRI scanning is definitive in the diagnosis of pheochromocytoma.

Wilms' tumour with IVC and right atrial thrombus

CT scan of 15 year old female shows large mass lesion (arrow head) in the left kidney pushing the aorta and IVC to right side and tumour is extending in to left renal vein (short arrow), IVC and into the right atrium (long arrow).

Vascular extension to the vena cava occurs in 4% of Wilms tumor cases and can reach the right atrium in up to 1%. When this happens the thrombus is usually not adherent to the vessel wall, and there is blood flow around it. Preoperative chemotherapy can cause thrombus regression and even resolution. If the thrombus persists after chemotherapy, surgery will be a challenge. On the other hand, if the thrombus invades the vessel wall, its removal may not be feasible. In this situation cavectomy is a good surgical strategy because it provides complete resection. The prerequisite for cavectomy is the absence of blood flow in the vena cava on preoperative Doppler ultrasonography.

Colon Lipoma

44 year old male presented to gastroenterology clinic complaining loose stools . Upper GI endoscopy was normal. Patient was referred for CT enteroclysis. The images revealed 4X3.5 cm well defined intralumnal fat attenuation lesion seen in the desecnding colon attached to the lateral wall. The findings are consistent with colonic lipoma.

Colon lipoma was described initially by Bauer in 1757. The incidence was estimated to be about 0.26%. colon lipoma constituted 0.3% of the cases treated for colorectal diseases and 1.8% of the cases of benign colorectal tumor during the same period. Elders are more likely to be involved. Most of the lesions were located at the right side of large bowel, accounting for nearly 90% of cases. The majority of colon lipomas presented as single while only 10% of cases were multiple. Most lipomas are submucosal while some are subserosal location. Some are sessile and some pedunculated. CT scan features of lipoma include well defined well capsulated fat attenuation lesion with not much enhancement are diagnostic of lipoma. MR shows hyperintense lesion on T1 and T2 W imagea and loss of signal in fat saturated images. Treatment is mainly by colonoscopic resection if the lesion is pedunculated and surgery if it is sessile.

The Double Posterior Cruciate Ligament (PCL) Sign - Bucket handle tear of medial meniscus.

25 year old young male soccer player presented with a 1 week history of his right knee locking and was not allowed to extend completely as he walked. On physical examination, the left knee appeared minimally swollen but did not feel warm. There was an audible click when the flexed left knee was extended while varus pressure was applied (McMurray test). MRI was performed, Sagittal fat saturated T2 weighted image of the right knee through the intercondylar notch reveals a thin linier fragment of torn meniscus which appears as a low-signal intensity longitudinally oriented band (arrow) lying beneath and parallel to the posterior cruciate ligament (arrow head), creating a double cruciate configuration, referred to as the double posterior cruciate ligament (PCL) sign. The abnormal hyperintensity in keen joint space and supra patellar region is joint effusion. Patient underwent arthroscopic repair of the torn ligament.

The double PCL sign is associated with bucket handle tears of medial meniscus, At MRI this sign relates to the peripheral (bucket) portion of the meniscus and the displaced inner fragment (handle) portion. Identifying the bucket-handle tears early is critical because, depending on how peripheral and complex the tear is, any delay can compromise the chances for repair. If the tear is not reduced, the meniscal fragment risks further maceration.

Pericardial cyst

A 40-year-old man came for routine health checkup. Chest radiograph was found to be abnormal. He said he had no symptoms, and the results of a physical examination were normal. The chest radiograph (Fig 01) showed a smoothly marginated density in the region of the left cardiophrenic angle that partially obscured the left border of the heart and left dome of diaphragm. A computed tomographic scan (Fig 02) showed a homogeneous and smooth fluid attenuation lesion abutting the left ventricle. No septations or calcifications. The heart and great vessels were otherwise normal, and there was no adenopathy. Coronal and sagittal reformated images (fig03) depict the lesion better. The findings are consistent with pericardial cyst.

Pericardial cysts are an uncommon benign congenital anomaly in the middle mediastinum. They represent 6% of mediastinal masses, and 33% of mediastinal cysts. Other cysts in the mediastinum are bronchogenic – 34%, enteric – 12%, thymic and others – 21%. In the middle mediastinum 61% of presenting masses are cysts. Pericardial and bronchogenic cysts share the second most common etiology after lymphomas.

On CT scan pericardial cysts are thin-walled, sharply defined, oval homogeneous masses . Their attenuation is slightly higher than water density 30 to 40 HU. They fail to enhance with intravenous contrast. USG shows hypoechoic lesion with no calcification or septations. MRI is diagnostic, they appear hypointense on T1 and Hyperintense on T2 W images. They will not enhance on contrast study.

Pulmonary alveolar proteinosis (PAP)

HRCT of 30 year old female shows welldefined ground glass opacities which is associated with marked intelobular septal thickening and a sharp nonanatomic demarcation between normal and abnormal lung suggestive of "Crazy paving" pattern which is typical of PAP.

Pulmonary alveolar proteinosis (PAP) is a rare (1 case per 2 million), diffuse lung disease that is characterized by the alveolar and interstitial accumulation of a periodic acid-Schiff (PAS) stain-positive phospholipoprotein that is derived from surfactant.The lung architecture is otherwise normal, and any associated inflammation or fibrosis is limited in extent. Pulmonary alveolar proteinosis (PAP) occurs in primary and secondary forms. Primary PAP is either idiopathic (90% of cases) or congenital (2% of cases) in origin, whereas secondary PAP occurs in association with various pathologies like hematologic malignancies, particularly chronic myeloid leukemia and lymphomas, occupational exposures and associated with infections. Congenital PAP results from deficiency of surfactant protein B (SP-B) or abnormality of the granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor β chain.

CT scan with the above findings are almost diagnostic. razy paving is the characteristic finding of PAP on high-resolution CT (HRCT) scanning and consists of patchy, bilateral, geographic areas of ground-glass opacity that are associated with interlobular septal thickening. The disease is often distributed uniformly from the lung apex to the base. Interlobular septal thickening may be encountered more frequently in the lower lung zones.Classically, the abnormal pulmonary parenchyma is demarcated sharply from normal lung areas without a discernible anatomic boundary.

The crazy paving pattern also seen in many other condition like hydrostatic pulmonary edema, diffuse alveolar damage from any number of causes, pulmonary hemorrhage, diffuse pulmonary infections (including M tuberculosis, M pneumoniae, and other bacterial pneumonias), the diffuse form of bronchioloalveolar carcinoma, ARDS, drug-induced pneumonitis, radiation pneumonitis, bronchiolitis obliterans organizing pneumonia, chronic eosinophilic pneumonia, obstructive pneumonitis, acute interstitial pneumonia, and lipoid pneumonia.

Hydatid cyst of neck

54 year old female came with neck swelling on the left side. CT scan showing flid attenuation lesion inthe left side of the neck extending to superior mediastinum (arrow). The lesion shows cyst in cyst appearance (arrow head) suggetive of daughter cyst. The findings are consistent with hydatid cyst.

Hydatid cysts in the neck are quite rare, even in areas where the disease is endemic. The role of radiological investigation is important and, in these cases, the involvement of other organs should be investigated. The cyst should be excised as a whole, without being ruptured, to prevent any treatment complications.

Carcinoma cervix with pyometra

CT scan of 52 year old female shows illdefined enhancing soft tissue lesion ( white arrow) in the region of cevix more on the right side with para metrial extnesion. The section through the body of uterus shows collection within the endometrial cavity. The findings are consistent with the carcinoma cervix with pyometra.

Invasive cervical cancer is the third most common gynecologic malignancy. The prognosis is based on the stage, size, and histologic grade of the primary tumor and the status of the lymph nodes. Assessment of the stage of disease is important in determining whether the patient may benefit from surgery or will receive radiation therapy. The official clinical staging system of the International Federation of Gynecology and Obstetrics has led to errors of 65%–90% in stage III and IV disease; the result has been unofficial extended staging with cross-sectional imaging modalities such as computed tomography (CT) and MRI. CT and MRI are useful in staging advanced disease and in monitoring patients for recurrence. The primary tumor is heterogeneous and hypoattenuating relative to normal stroma on contrast material–enhanced scans. Obliteration of the periureteral fat plane and a soft-tissue mass are the most reliable signs of parametrial extension. Less than 3 mm separation of the tumor from the pelvic muscles and vascular encasement are signs of pelvic side wall invasion. Lymphatic spread is along the external and internal iliac nodal chains and the presacral route to the paraaortic nodes. Distant metastases are seen with primary or recurrent disease and can involve the liver, lung, and bone.

Non Alcoholic Steatohepatitis (NASH)

15 year old male obese boy came with pain in abdomen with elevated liver enzymes. He is non alcoholic, not taking any medication and tests negetive for hepatitis. MRI abdomen T1 weighted image shows diffuse fatty infilteration in the liver which is confirmed by loss of signal on ooposed phase chemical shifgt image. Findings are consistent with Non Alcoholic Steatohepatitis (NASH).

Synonyms: Hepatic fatty metamorphosis , Hepatic fatty steatosis, NASH

Nonalcoholic steatohepatitis (NASH) is fat in the liver, with inflammation and damage. It resembles alcoholic liver disease, but occurs in people who drink little or no alcohol. The major feature in NASH is fat in the liver, along with inflammation and damage.Patients generally feel well in the early stages and only begin to have symptoms—such as fatigue, weight loss, and weakness—once the disease is more advanced or cirrhosis develops.

We have to differentiate "Fatty liver", NASH and nonalcoholic fatty liver disease (NAFLD). Fat in their liver, but no inflammation or liver damage, a condition called “fatty liver. If fat is suspected based on blood test results or scans of the liver, this problem is called nonalcoholic fatty liver disease (NAFLD). If a liver biopsy is performed in this case, it will show that some people have NASH while others have simple fatty liver. Main causes for the NASH are elevated blood lipids, such as cholesterol and triglycerides, and many have diabetes or pre-diabetes, obesity.

USG shows diffuse increase in echotexture. CT scan will show diffuse decrease in attenuation. MRI shows intracellular fatty infilteration which is diffusely hyperintense on T1 weighted image (in phase image) and shows loss of signal on opposed phase chemical shift image. These MRI findings in patient with elevated liver enzymes suggestive of NASH. Liver biopsy and histopathology are diagnostic.

Tarlov Cyst

25 year old young male came with radicular pain to lower limb on right side referred for MRI LS spine. MRI T2 weighted para saggital image shows well defined rounded hyperintense lesion in the D12-L1 intervertebral foramen causing compression on the exiting nerve root on right side. CISS 3D axial image shows the lesion better (arrow).

Tarlov or perineurial cysts are pathological formations located in the space between the peri-and endoneurium of the spinal posterior nerve root sheath. Tarlov cysts are rare causes of low back pain. They are more common in females. Clinical presentation of Tarlov cysts is variable. The cysts may cause local and/or radicular pain. Depending on their location, size and relationship to the nerve roots, they may cause sensory disturbances or motor deficits to the point of bladder dysfunction.

Radiograph is usually normal, it may show bony erosion or widening of foramen on oblique views. Conventional myelography may show extradural indentation on the thecal sac however MRI is needed for confirmation of the lesion. CT scan can demonstrate cystic lesion isodense with CSF located at the foramina. Bony changes may also be present. MRI shows welldefined CSF intensity lesion in the prineural location predominantly in lumbar and sacral region. The lesions may be seen in the cauda equina and other nerve roots.

Supraspinatus Tendonitis

44 year old male patient came with painfull arc of shoulder movement, T1 weighted oblique coronal image shows hyperintense abnormal signal seen in the supraspinatous tendon (arrow).

Supraspinatus tendonitis is often associated with shoulder impingement syndrome. The common belief is that impingement of the supraspinatus tendon leads to supraspinatus tendonitis (inflammation of the supraspinatus/rotator cuff tendon and/or the contiguous peritendinous soft tissues), which is a known stage of shoulder impingement syndrome.

It is basically chronic degenerative tendinitis leading to some degree of mucoid degeneration seen on MRI as increased signal intensity without altered rotatory cuff contour. Increased signal intensity appreciated on T1 and PD weighted images.

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Arnold chiari malformation type 1

T2 W MR sagittal cervical spine image shows herniation of cerebellar tonsils with extensive syrinx in cervical and dorsal spinal cord.

Chiari I malformation (CMI) is characterized by herniation of the cerebellar tonsils through the foramen magnum into the cervical spinal canal. The cerebellar tonsils often are elongated and peglike. Mild caudal displacement and flattening or kinking of the medulla may be present. The vermis cerebelli and the fourth ventricle are normal or only minimally deformed. Its symptoms may result in occipital headache, difficulty swallowing, numbness and tingling in the hands.

Distention with cerebrospinal fluid (CSF) of the central canal of spinal cord (ie, hydromyelia) or paracentral cavities (Syringomyelia) is present in approximately 25% of patients with CMI. The cervical cord is the most common site of syringohydromyelia.

Classification:

Type	Presentation	Other notes
I	Is generally asymptomatic during childhood, but often manifests with headaches and cerebellar symptoms. Herniation of cerebellar tonsils.	The most common form.
II	Usually accompanied by a myelomeningocele leading to partial or complete paralysis below the spinal defect. Abnormal development of the cerebellar vermisand medulla oblongata occur, and they both descend into the foramen magnum. Hydrocephalus is frequently present.
III	Causes severe neurological defects. It is associated with an encephalocele.
IV	Characterized by a lack of cerebellar development.

Here is a youtube link to a nice video created by on of the patients father..........

http://www.youtube.com/watch?v=T2uN6zDsV50

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Renal vein thrombosis (RVT)

45 Year old male doctor presents with breathlessness and fever, pulmonary angio revealed thromboembolism in segmental pulmonary arteries on right side. Bilateral lower limb doppler is negetive. Patient was obese to carryout abdominal doppler. MR angiogram thick MIP image shows partially occluding thrombus in the left renal vein extending partially in to IVC (arrow).

Although renal vein thrombosis (RVT) has numerous etiologies, it occurs most commonly in patients with nephrotic syndrome. The renal vein also may contain thrombus after invasion by renal cell cancer (Resources from Elsevier’s OncologySTAT). Other less common causes include renal transplantation, Behçet syndrome, hypercoagulable states, and antiphospholipid antibody syndrome.

Although colour doppler can pick up renal vein thrombosis, CT and MRI are better midalities for the diagnosis.

Fracture of the Dens (Type 1)

24 Year old male came with motor vehicle accident with pain in neck, Sagittal T1 W and Coronal STIR MRI images of cervical spine shows an oblique fracture in the tip of odontoid process (arrow). No cord compression.

Discussion:

• Most dens fractures are caused by motor vehicle accidents and falls
• About 1/3 of C-spine injuries occur at C2 and about ½ at C6-C7
• As expected, most fatal cervical spine injuries occur at C1 or C2
• Most odontoid fractures occur with flexion, extension and rotation.

• Classification of dens fractures:
• About 15% of all cervical spine fractures
• Classified by location (Anderson and D’Alonzo classification)
• Type I (<5%)
• Tip of dens at insertion of alar ligament which connects dens to occiput
• Usually stable but may be associated with atlanto-occipital dislocation
• Type II (>60%)
• Most common dens fractures
• Fracture at base of dens at its attachment to body of C2
• Type III (30%)
• Subdentate—through body of C2
• Does not actually involve dens
• Unstable fracture as the atlas and occiput can now move together as a unit
• Other fractures include a rare longitudinal fracture through dens and body of C2

• Imaging findings
• Conventional radiography is frequently first used as it tends to be most available
• CT is better at demonstrating fractures
• MRI is used for evaluation of ligamentous, disk, spinal cord and soft tissue injuries
• Posterior displacement of the fractured dens into the spinal canal is more common than other displacements
• Lateral view on conventional radiography is most useful as most (85-90%) of injuries can be seen on lateral view
• Cervicothoracic junction visibility assures that the entire cervical spine is visualized
• Soft tissue findings may include >5 mm of prevertebral soft tissue at C3 or less than half of the AP diameter of the adjacent vertebra
• At level of C6, prevertebral soft tissue should be no more than 22 mm in adults and 14 mm in children younger than 15 years
• Widening of the predentate space to greater than 3 mm is abnormal
• Pitfalls
• A mach line may appear to traverse the base of the dens on the open-mouth (aka as the atlantoaxial or odontoid) view but should be recognized by the superimposed base of the occiput
• The mach line will not be present on the lateral view of the dens
• A smooth and sclerotic edge to the “fracture” usually indicates either congenital non-union or acquired non-union of the dens to the body of C2
• Treatment
• Type I fractures are usually treated with a hard collar for 6-8 weeks
• Type II fractures can be treated with
• Immobilization for 12-16 weeks
• Operative fixation (odontoid screw)
• Arthrodesis of C1 to C2
• Type II fractures can be treated with a halo or surgically, as Type II fractures
• Complications
• Non-union
• Due to limited vascular supply
• May occur in 30-50% of Type II fractures, especially in elderly
• Malunion
• Pseudarthrosis
• Affected by age of patient, amount of displacement.

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Horse shoe kidney

The term horseshoe kidney refers to the appearance of the fused kidney, which results from fusion at one pole. In more than 90% of cases, fusion occurs along the lower pole. Technically, the term horseshoe kidney is reserved for cases in which most of each kidney lies on one side of the spine. It includes symmetric horseshoe kidney (midline fusion) or asymmetric horseshoe kidney (L-shaped kidney). In the latter, the fused part, or isthmus, lies slightly lateral to the midline (lateral fusion). Horseshoe kidney is generally differentiated from crossed fused ectopia, in which both fused kidneys lie on one side of the spine, and the ureter of the crossed kidney crosses the midline to enter the bladder.

Horseshoe kidney is the most common renal fusion anomaly, the incidence being about 1 case per 400 persons worldwide. As reported, it can occur in a single member of a set of identical twins and in both members. At present, no clear evidence of a hereditary trait exists.

Complications of horseshoe kidney include the following:

• Ureteropelvic junction (UPJ) obstruction is a common complication, possibly because of the high insertion of the ureter.
• Recurrent infections occur because of urine stasis and associated vesicoureteric reflux.
• Recurrent stone formation related to UPJ obstruction or infection may occur.
• An increased risk of trauma to the isthmus exists because of its position anterior to the spine.
• Horseshoe kidney may pose problems for surgeons during abdominal surgery for other abdominal problems.
• Evidence indicates that an increased incidence of certain renal tumors is associated with horseshoe kidney.

Spine fracture in Ankylosing Spondylitis

38 year old male patient with ankylosing spondylitis met with mild trauma following which he presented with para paresis, Sagittal T2 weighted MR image showing anterior displacement of C6 over C7 (Arrow head) and multiple syndesmophytes in all the cervical levels (short arrow). There is cord hyperintensity at the levels of C6, C7 and D1 suggestive of cord contusion due to fracture.

The diffuse paraspinal ossification and inflammatory osteitis of advanced ankylosing spondylitis creates a fused, brittle spine that is susceptible to fracture. Even minor trauma can produce an unstable injury as a result of disruption of the ossified supporting ligaments.

Thoracolumbar fractures are reported less frequently than cervical injuries in patients with ankylosing spondylitis.Three recognized patterns are simple vertebral compression fractures, transversely oriented shear fractures, and stress fractures associated with pseudoarthrosis. Transversely oriented shear fractures are acute fractures of the ankylosed spine that invariably disrupt the ossified supporting ligaments and usually traverse the disk space. Disruption of all three columns of the spine predisposes the fracture to displacement and neurologic injury. Stress fractures associated with pseudoarthrosis are subacute injuries that constitute part of the spectrum of spondylodiscitis, a destructive discovertebral (“Andersson”) lesion, that tends to occur in the thoracolumbar region. End-plate erosions and disk height changes, with vertebral sclerosis or osteolysis, can be seen radiographically.

Shiny corner sign in Ankylosing Spondylitis

38 year old male with recently diagnosed ankylosing spondylitis, lateral lumbar spine radiograph showing increased density (arrow) in the anteroinferior part of L3 vertebral body suggetive of shiny corner sign. MR STIR image shows increased signal in anteroinferior parts (arrows) of L3 and L5 bodies.

Shiny corner sign, also known as a Romanus lesion, is an early spinal finding in ankylosing spondylitis. These represent small erosions at the superior and inferior endplates (corners on lateral radiograph) of the vertebral bodies, with surrounding reactive sclerosis. Eventually the vertebral bodies become squared.

On MRI the 'shiny corners' appear as areas of increased T1 signal due to focal fatty marrow as a result of chronic inflammation. MRI however can detect changes earlier than x-ray manifestations, when there is initially increased T2 signal on STIR and decreased signal on T1WI. At this stage plain films appear normal.