Cardiac hydatid cyst

CT scan of 58 year old male patient showing large well defined well capsulated hypodense lesion seen in the myocardium of the left ventricle with multiple daughter cysts within suggestive of hydatid cyst.

• Hydatid disease is a parasitic infection caused by larvae of Echinococcus granulosus, which is still endemic in many sheepraising countries.
• Hydatid cysts can be located in various tissues, although they are most common in the liver (50–70% of cases) and the lung (20–30% of cases) in humans.
• Cardiac involvement in hydatid disease is uncommon, constituting only 0.5–2% of all cases of hydatidosis.
• Heart involvement - LV – 60%, RV – 10%, pericardium – 7%, pulm Artery – 6%, left atrial appendage – 6%, and interventricular septum is rare – 4%.
• Cardiac involvement occurs by invasion of the myocardium - Through coronary circulation or pulmonary vein from rupture of pulm cysts in to vein.

• Signs and Symptoms •No symptoms due to its latency and slow growing nature unless it is situated in critical site. •Signs and symptoms are extremely variable and directly related to location and size of the cysts. •Precordial pain is the most common symptom and is most often vague and does not resemble angina pectoris. •Sudden rupture of intracardiac cysts is a frightful complication and can cause acute pericarditis or tamponade, acute pulmonary hypertension by embolization of several scolices, systemic arterial embolization, and severe anaphylactic shock can be life thretening.

• Imaging - Echocardiography, CT, and MRI can show the cystic nature of the mass and its relation to the cardiac chambers •CT best shows wall calcification. •MRI depicts the exact anatomic location and nature of the internal and external structures and is the technique used for posttreatment follow-up.
• The appearance of a hydatid cyst on MRI is usually a characteristic oval lesion that is hypointense on T1-weighted images and hyperintense on T2-weighted images. •A typical finding on T2-weighted images is a hypointense peripheral ring, which represents the pericyst (a dense fibrous capsule from the reactive host tissue). •A variety of tumors in the heart and a congenital pericardial cyst must be considered in the differential diagnosis; however, the multivesicular nature of the cystic mass and membrane detachment indicate the true diagnosis.
• The cysts may be single or multiple, uni or multiloculated, and thin or thick walled. •More specific signs are •Cyst wall calcification. •Presence of daughter cysts and Membrane detachment.
• •Surgery remains the treatment of choice in the management of hydatid disease. •Although antihelminthic drugs have been used in the preoperative and postoperative periods since 1977, extirpation of the lesion under cardiopulmonary bypass is recommended.
• To conclude CT and MRI are helpful for localizing and defining the morphologic features of hydatid cysts. •Specific signs include calcification of the cyst wall, presence of daughter cysts, and membrane detachment. •CT best shows wall calcification, whereas MRI depicts the exact anatomic location and nature of the internal and external structures.

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.

Focal Pyelonephritis

40 year old male patient came to emergency with history of right lumbar pain and fever, USG Doppler of right kidney shows focal hypoechoic area in upper pole with small anechoic area within. CT scan of the same patient showwed focal hypoenhancing lesion in upper pole of right kidney with small non enhancing area within. These features are suggestive of focal pyelonephritis with evolution of abscess.

Acute focal pyelonephritis (AFP) is a variant of pyelonephritis in which single or multiple discrete areas show changes of inflammation. The sonographic appearances of AFP are varied and can be echogenic, echopoor or of mixed echogenicity, but are typically described as being echopoor. CT typically shows focal hypoenhancing areas. Imaging is done mainly to identify the complications like intra renal and peri renal abscess.

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.

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.

Cholesterol gallstones

Fig1: CT scan of 57 year old female shows multiple hypodense small lesions of fatty attenuation seen in the gall bladder suggestive of cholesterol gall stones. Fig 2: USG of gall bladder shows multiple calculi in the GB.

Gall stones are of two types: 1. Cholesterol stones and 2. Pigment stones.

Cholesterol stones are made primarily of cholesterol of 70-80%. Where as pigment stones contain only 20% of cholesterol. Ultrasound is the most sensitive and best investigation for the diagnosis of cholelithiasis. CT can pick up calcified gall stones and cholesterol stone which contain more amount of cholesterol. Cholesterol stones appear dark on the background of isoense bile on CT. CT can miss gallstones which are not calcified.

Hydatid cyst of Liver

Multiphasic study of 55 year old male patient non contrast image shows well defined fluid attenuating lesion seen in the segment 8 of liver with rim calcification. The lesion does not show enhancement on arterial and venous phase. The findings are consistent with calcified hydatid cyst. (Type 5).

The liver is the commonest organ to be involved by the hydatid disease. The hydatid cyst can attain very large size before causing symptoms or may be incidentally dectedted early on investigation.

Types of hydatid cyst accodring to Gjarbi's classification bases on uSG appearance:

Type 1 : Pure fluid collection.

Type 2 : Fluid collection with a split wall.

Type 3 : Fluid collection with daughter cysts.

Type 4 : Heterogenous echopattern.

Type 5: Completely calcified lesion.

Preffered management is combination of Albendazone and PAIR techniqe - Puncture, Aspiration, Injection and Re-aspiration (PAIR).

Pracedure : Percutaneous drainage is performed under aseptic conditions with continuous sonographic guidance and intensive monitoring to treat any complications. Using a transhepatic approach, the cyst punctured by a 20-gauge needle and cyst contents aspirated rapidly. After aspiration, the cyst should be filled with a near-equal volume of 95% ethanol which will be left in the cavity for 20 min. Finally the cyst is reaspirated, irrigated and left partially filled with sterile 0.9% saline. Before and after injection of 95% ethanol, cyst fluid should be sent immediately for cytological and microbiological examination. Staining with neutral red is indicated in a viable cyst, while staining with methylene blue and eosin indicated in a non-viable cyst. Percutaneous drainage will be successful if the endocyst separated from the pericyst and if the reaspirated fluid shows a non-viable cyst. If not, percutaneous drainage was repeated at the same sitting to obtain success. After percutaneous drainage had been performed, all patients should be given albendazole 10 mg/kg body weight for 6 weeks. Othre treatment option is surgery which includes morbidity and mortality.

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.

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.

Rheumatoid pneumoconiosis (Caplan's Syndrome)

High resolution CT of 84 year old man with rheumatoid arthritis. a) Mediastinal window image showing cavitatory lesions in bilateral upper lobes (arrows) with large fibrotic area in right upper lobe (arrow head) and few subpleural fibrotic lesions (arrows in image [b]) in left upper lobe. c) High resolution CT scan lung window shows multiple diffuse reticulonodular lesions in bilateral lungs these features suggestive of pneumoconiosis with progressive massive fibrosis (PMF).

It is also known as Caplan's Syndrome, associated with coal worker's pneumoconiosis and silicosis. The incidence is falling as the coal mining industry has been in decline. Chest radiograph shows multiple, well defined, rounded opacities, 0.5 to 5 cm in diameter distributed throughout the lungs with or without eggshell calcification of hilar lymph nodes. HRCT findings include small nodules with perilymphatic distribution associated with necrobiotic nodules demonstrating cavitation, which are indistinguishable from tubercular cavity. The active inflammatory zone around the rheumatoid pneumoconiotic nodules distinguishes from nonrheumatoid pneumoconiotic nodules. Progressive massive fibrosis (PMF) is irregularly outlined few soft tissue nodules with surrounding fibrosis in apical regions, more often seen with simple pneumoconiosis than Caplan’s syndrome.

Tracheal bronchus

5 month old male child with acute respiratory tract infection, CT coronal reformatted lung window shows bronchus arising from the trachea on right side (arrow) and the virtual bronchoscopy image shows the tracheal bronchus opening better.

The term tracheal bronchus refers to an abnormal bronchus that comes directly off the lateral wall of the trachea (ie, above the main carina) and supplies ventilation to the upper lobe. It is most often an asymptomatic anatomical variant found on bronchoscopy. There is an association

between tracheal bronchus and other congenital malformations, mainly malformations of the ribs and vertebrae. Patients with Down syndrome have a higher incidence of tracheal bronchus. The anomalous bronchus can arise anywhere from the carina to the cricoid cartilage, but most frequently within 2 cm of the carina. Tracheal bronchi are classified as being either “displaced” or “supernumerary.”

If the entire right upper lobe takes off from the trachea the right main bronchus is the bronchus intermedius, feeding the right middle and lower lobes, and the malformation is called “true tracheal bronchus” or “bronchus sui” (“pig bronchus,” because that is the normal morphology in pigs). The incidence of true tracheal bronchus is 0.2%.

If the anomalous bronchus is the take-off of the apical segment of the right upper lobe, as was the case in our patient, the right main bronchus will be normal looking, but the right upper lobe will not have its trifurcation. Instead there will be a bifurcation, corresponding to the anterior and posterior segments. That variant is called “apical tracheal bronchus,” which has been described in patients who have an azygos lobe. In that situation the apical segment will have its own displaced bronchus and its ownpleural investment. Vascular supply and venous drainage are usually normal in the displaced bronchus variant and are provided by the pulmonary artery and pulmonary veins.

The majority of patients with tracheal bronchi are asymptomatic and do not require any medical intervention. In the case of recurrent pneumonia complicated by bronchiectasis surgical resection of the anomalous lobe or segment is the treatment of choice.

Small-cell lung carcinoma invading the left atrium

60 year old male came with progressive shortness of breath and chest pan, Contrast enhanced CT scan showed large heterogenously enhancing lesion (arrow in first image) in the left perihilar and lower lobe region occluding the left lower lobe bronchus completely. The lesion is partially encasing the descending thoracic aorta and extending in to the left atrium through the inferior pulmonary veins (arrow in secong image and arrow head in third image) . The biopsy of the lesion revealed Small cell carcinoma of lung.

Direct intravascular, cardiac extension and spread of bronchogenic carcinoma is an uncommon event. when tumor extends to left atrium, special techniques are needed is resectrion of still to be attempted.

The cardinal imaging signs of intarvenous extension of bronchogenic carcinoma on CT or MRI is filling defect of soft tissue density within the lumen of pulmonary vein and left atrium, which is continous with the primary mass. Obliteration of superior pulmonary vein is regardes as suggesting as intrapericardial tumor extension. CT remains the standard staging investigation for lung carcinoma.