Tuesday, July 29, 2008

Arachnoiditis



Few MR images from a case of tubercular arachnoiditis.

Round Atelectasis


This is a case of treated tubercular pleural effusion with rounded opacity showing characterstic apearance of round atelectasis. The characteristic feature of round atelectasis is the comet tail sign. As the lung collapses, the vessels and bronchi that lead to the mass are pulled into the region. As they reach the mass, they diverge and arch around the undersurface to merge with the inferior pole of the mass.


Dr.Sumer K Sethi, MD

Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers

Editor-in-chief, The Internet Journal of Radiology

Director, DAMS (Delhi Academy of Medical Sciences)

Monday, July 28, 2008

Radiology Grand Rounds XXVI





Here is a case of Reflex Sympathetic Dystrophy of Ankle for the Radiology Grand Rounds submitted by Dr Sumer Sethi of Teleradiology Providers. Concept and Archive of the Radiology Grand Rounds is available at- Radiology Grand Rounds


This is 44 year old male with history of ankle injury six months back with history of severe pain in ankle now and swelling. Bone scan done showed increase uptake around the ankle. MRI study was requested which revealed patchy marrow edema involving the bones forming tibiotalar and subtalar articulation with myofascial edema and synovial collection. A diagnosis of Reflex sympathetic dystrophy was made. The diagnosis of Reflex Sympathetic Dystrophy Syndrome (RSDS) can be difficult to establish. RSDS is a devastating condition, which can cause patients to become socially and emotionally crippled. MRI abnormalities seen in patients with RSDS of the foot vary widely and include marrow edema, synovial hypertrophy, joint effusions and soft tissue edema. However, normal MRI does not rule out RSDS of the foot.


Saturday, July 26, 2008

Knee Trauma



Note the non-visualization of ACL fibres beyond the femoral origin suggesting complete tear. Also note that the PCL is streched. There is an intraarticular bony loose body as a result of osteochondral injury in the tibial plateau.

Ischemic Stroke-MRI



This is diffusion weighted image showing left MCA territory acute infarct. MRA brain done at the time shows left MCA block with diffuse atherosclerotic changes.

Craniovertebral Gout






This is an old male patient who is a known case of gout with raised uric acid levels and neck pain. MRI cervical spinhe revealed C1-2 erosions and marrow edema, with retro-odontoid soft tissue which is isointense on T1 WI and hypointense on T2 WI. There was no significant post gadolinium enhancement. CT scan revealed erosive disease and retro-odontoid high density soft tissue. There was no evidence of tuberculosis and rheumatoid factor repeatedly was negative. Although rare but still possible gouty cystal deposition was the provisional diagnosis made and patient was followed up after 3 months with no serial change.


Dr.Sumer K Sethi, MD

Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers

Editor-in-chief, The Internet Journal of Radiology

Director, DAMS (Delhi Academy of Medical Sciences

Thursday, July 24, 2008

CP angle vascular malformation


The most common cause of tinnitus is high jugular bulbus followed by atherosclerosis, dehiscent jugular bulbus, aneurysm of internal carotid artery, dural arteriovenous fistula, aberrant internal carotid artery, jugular diverticulum, and glomus tumor. This is case who presented with pulsatile tinnitus. Radiologic imaging methods are effective in detecting the underlying pathology of pulsatile tinnitus.


Dr.Sumer K Sethi, MD
Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers
Editor-in-chief, The Internet Journal of Radiology
Director, DAMS (Delhi Academy of Medical Sciences

Cervical Spine Trauma


Note the C5-C6 fracture dislocation with retropulsion and disc extrusion with long segment haemorhagic cord contusion. This is a young male who presented with history of RTA.

CNS Lymphoma-MRI





This is a 58year old known case of NHL presented with right sided weakness. MRI showed hypointense areas in the midbrain and thalamocapsular region with hyperintense appearance on FLAIR with areas of hypointensity. There is evidence of homogenous post gadolinium enhancement and few areas of diffusion restriction on DWI suggesting cellularity. Diagnosis of CNS involvement of systemic lymphoma was made.

Wednesday, July 23, 2008

Internet Journal of Radiology-Current Issue

Here is the Table of contents for the current issue of Internet Journal of Radiology
Original Articles
A Retrospective Analysis of Referral Pattern from General Practitioners for Musculoskeletal Ultrasound to a Tertiary Centre - Surabhi Choudhary, K. Jeypalan, Raj Bhatt.
Reviews
Spectrum Of MRI Findings In Musculoskeletal Tuberculosis: Pictoral Essay - Priya Darshan Chudgar.
Quizzes
Abdomen Quiz - Priya Darshan Chugar.
Head And Neck Quiz - Priya Darshan Chudgar.
Case Reports
An Unusual Kind Of Traumatic Intracranial Hemorrhage: Post Traumatic Bleed Into The Schizencephalic Cleft - Janeesh T, V. R. Rajendran, E. Devarajan.
An Unusual Cause Of Small Bowel Obstruction By Dead Mesenteric Calcified Hydatid Cyst - M. El Fortia, A. Juwid, Sumer Sethi.
Cerebral Echinococcosis - El Fortia Mohamed, Benmusa Abdulmatloub, Bendaoud Maroua, Sumer Sethi.
Bilateral Congenital Capitate-Trapeziod-Trapezium Fusion - Johnson Dare Ogunlusi, R. St. George B. St. Rose, Tamunotoyen Davids.
Intradural Lipoma Without Spinal Dysraphysm With Spinal Cord Involvement - Balla Suresh, K Anasuyamma, Mamilla Devi Uma, D. Prashanth Madhu, M. V. Ramanappa.
Port-Site Hernia Vs Spigelian Hernia: A Diagnostic Confusion - Fayyaz Akbar, Melissa Tan, Andrew Maw.
Web 2.0 and Radiology - Sumer K. Sethi.
Letters
Images In Radiology: Because Sometimes Pictures Speak Louder Than Words - Shilpa Singla, Sidharth Kumar Sethi.

Monday, July 21, 2008

Prostate MRS

The prostate lends itself to MRS due to its unique production, storage, and secretion of citrate. While healthy prostate tissue demonstrates high levels of citrate and low levels of choline that marks cell wall turnover, prostate cancer (PCA) utilizes citrate for energy metabolism and shows high levels of choline. The ratio of (choline + creatine)/citrate differentiates healthy prostate tissue and PCA. The combination of magnetic resonance imaging (MRI) and 3-dimensional MRS (3D-MRSI or 3D-CSI) of the prostate localizes PCA to a sextant of the peripheral zone of the prostate with sensitivity/specificity of up to 80/80%.
Further reading-
Radiologe 2003 Jun;43(6):481-8.
Eur J Radiol 2007 Sep;63(3):351-60. Epub 2007 Aug 20

Sunday, July 20, 2008

Hemimegalencephaly




Hemimegalencephaly or unilateral megalencephaly is a congenital disorder in which there is hamartomatous overgrowth of all or part of a cerebral hemisphere . The affected hemisphere may have focal or diffuse neuronal migration defects, with areas of polymicrogyria, pachygyria, and heterotopia. Hemimegalencephaly is a rare disorder and was first described by Sims in 1835.
Although the cause is unknown, it is postulated that it occurs due to insults during the second trimester of pregnancy, or as early as the 3rd week of gestation, as a genetically programmed developmental disorder related to cellular lineage and establishment of symmetry . Hemimegalencephaly may also be considered a primary disorder of proliferation wherein the neurons that are unable to form synaptic connections are not eliminated and are thus accumulated. No chromosomal abnormalities have been associated with hemimegalencephaly.
The isolated form, , occurs as a sporadic disorder without hemicorporal hypertrophy or cutaneous or systemic involvement.
The syndromic form is associated with other diseases and may occur as hemihypertrophy of part or all of the ipsilateral body. It has been described in patients with epidermal nevus syndrome, Proteus syndrome, neurofibromatosis type 1, hypermelanosis of Ito, Klippel-Weber-Trenaunay syndrome, and tuberous sclerosis. The third and least common type is total hemimegalencephaly, in which there is also enlargement of the ipsilateral half of the brainstem and cerebellum.

Epilepsy is the most frequent neurologic manifestation, occurring in greater than 90% of patients A characteristic finding is straightening of the ipsilateral frontal horn of the enlarged ventricle. At MR imaging, the white matter shows heterogeneous but frequently high signal intensity and there is often distinction of areas of agyria, pachygyria, and/or polymicrogyria. The white matter of the affected hemisphere may show advanced myelination for age . There is a roughly inverse relationship between the severity of the cortical and white matter abnormalities and the size of the cerebral hemisphere. Patients with agyria tend to have mild to moderate hemispheric enlargement, while those with polymicrogyria have more severe hemispheric enlargement .
Functional imaging with positron emission tomography has had good correlation with CT and MR imaging findings and has disclosed functionally abnormal brain regions in the noninvolved hemisphere that appeared structurally normal at CT and MR imaging.


Case by Dr MGK Murthy, Sr Consultant Radiologist
&
Dr.Sumer K Sethi, MD
Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers

Tuesday, July 15, 2008

Scoliosis with diastematomyelia

.

Diastematomyelia is a common association with congenital scoliosis.

Dr.Sumer K Sethi, MD
Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers
Editor-in-chief, The Internet Journal of Radiology
Director, DAMS (Delhi Academy of Medical Sciences

Tuberous Sclerosis



"Cortical tubers, or hamartomas, are the most characteristic lesions of tuberous sclerosis. The appearance of cortical tubers on MRIs varies with patient age. In neonates and young children, the cortical tubers and subependymal nodules are hyperintense on T1-weighted images and hypointense on T2-weighted images. In older children and adults, the cortical and subependymal lesions are isointense or hypointense on T1-weighted images. They are hyperintense relative to gray matter, as well as white matter, on T2-weighted images, depending on the presence of calcification."

Dr.Sumer K Sethi, MD
Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers

Friday, July 11, 2008

Radiology Education-Link

the Radiology Assistant is the educational web site of the Radiological Society of The Netherlands.Their focus is on common radiological issues in a problem oriented way for radiology residents and radiologists.

Thursday, July 10, 2008

Dural Ectasia-MRI




This is case of this is dural ectasia without neurofibromatosis in the brain and spine showing scalloping, hydrosyrinx and tonsilar herniation.



Case by Dr MGK Murthy, Sr Consultant Radiologist
&
Dr.Sumer K Sethi, MD, Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers
Editor-in-chief, The Internet Journal of Radiology
Director, DAMS (Delhi Academy of Medical Sciences

Wednesday, July 09, 2008

Acoustic Neuroma-MRI



MRI Brain revealed a well defined, lobulated, heterogenous, multicystic mass lesion in the right cerebello pontine angle extending into the jugular foramen on the right side with mass effect and obstructive hydrocephalous. A right retro mastoid sub occipital craniectomy & microsurgical tumour decompression was done. Part of the tumor extending into jugular foramen was left behind as it was closely adherent to lower cranial nerves. Neurilemmoma was confirmed on histology.



Dr.Sumer K Sethi, MD

Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers

Editor-in-chief, The Internet Journal of Radiology

Director, DAMS (Delhi Academy of Medical Sciences

3T MRI for musculoskeletal system


3T-MRI (3 Tesla magnetic resonance imaging) is MRI done with a stronger magnet. Magnet “strength” is like “pixels” in digital cameras. The stronger the magnet—or greater the number of pixels—the better the images. “Tesla” is a unit of “magnetic field.” By using a magnet that has 3 Teslas (“3T”), we get better and sharper pictures, and can get them in less time weaker magnets. A 3T-MRI produces better images than 1.5, OPEN MRI or any MRI with a weaker magnetic field.
Musculoskeletal MRI is better at 3T for several reasons. 3T has higher “signal to noise” than other MRI scanners and this makes MR imaging of the joints faster, sharper (higher resolution) and more detailed (for trabecular detail). Increased trabecular detail—known to be better at higher field strengths—shows stress fractures much more clearly and important as treatment for a bone bruise can be different from the treatment you would receive for a fracture.

3T MRI is also twice as sensitive to contrast enhancement. This makes indirect arthrography an option at 3T. With a 3T MRI, we can give you an arthrogram without having to inject contrast into the joint. This reduces the costs and saves you, the patient, the pain and possible infection related to an injection. Complications are also reduced; sometimes injections do not actually get into the joint. Studies on our 3T MRI cost the same as MRIs on lesser scanners and are more detailed in contrast and enhancement.

Fat saturation of the joints is also improved at 3T. So when you combine fat saturation (fat sat) with “contrast” better, more sensitive, studies of areas of inflammation, tumors and healing result. Increased blood flow and enhancement is easier to detect when you use fat sat and is easier to detect at 3T. The images our machine produces are so incredible that some orthopedic surgeons say they have NEVER seen such detail on an MRI. Hamstring injuries look much better and more extensive at 3T, as do “groin hernias.” At 3T, using this combination of fat saturation and contrast, areas of subtle inflammation—previously undetectable—are now visible. Also, we are able to scan with a very small field of view, which is essentially like being able to enlarge (or do a close-up of) the area we are studying. This is a great advantage when scanning hands and feet. Details of the bones, joints and wrists that were previously only seen in pathological or autopsy specimens are visible on these more powerful, 3t MRI scanners. We are able to see details of the response to treatment of rheumatoid arthritis medication in a non-invasive manner. .

The extra power of 3T MRI lets us scan most areas in contiguous (and thinner) sections. This means we are able to scan up to 30% more of the body. Due to time considerations, other MRI scanners scan with a “skip”—scanning one or more slice and then skipping a section before scanning the next slice. A very small tumor or lesion might hide in the area that is “skipped.” Because 3T imaging is faster as well as stronger, we are able to scan everything in the area of question without making the patient stay in the scanner for hours. Contiguous imaging means there is simply nowhere for an abnormality to hide. Our scans are often 512x512 matrix and 2mm thin—about 8 times the resolution of any other scanner. At 3T, we can do this in 3 minutes. This translates into several important advantages. Scanning more quickly means the patient doesn’t have to remain still for as long a period, which means the chances of getting a motion-free scan are greatly increased. The 3-minute scan mentioned above is actually done in two parts (two runs) so you only have to stay still for 1.5 minutes at a time to get motion-free images. This means that even the most fidgety or claustrophobic person can usually get a diagnostic scan. Higher signal to noise (which is doubled at 3T) theoretically means the scan can be done four times faster than at 1.5T (we do not recommend getting an MRI at less than 1.5T). In practice, however, we prefer to say we scan “twice as fast.” People have a harder and harder time remaining absolutely still for long periods of time. Being able to produce a better scan in half the time is a great step forward.

Bringing more sensitivity to trabecular detail makes our bony imaging much more detailed and greatly increases sensitivity to bone marrow tumors and subtle stress fractures.
The ability to scan with thinner sections and higher resolution also directly impacts our ability to see abnormalities. Images of lower resolution and detail are less likely to show abnormalities. Being able to scan with more pixels has given us the ability to see very subtle things, like small areas of arteriovenous shunting, or subtle areas of inflammation or microtrauma. Individual fibers of the anterior cruciate ligament of the knee or the subtle fibers of the calcaneofibular ligament in the ankle are visible at 3T. We see more and, as a direct result, can diagnose more abnormalities.

Ionizing radiation is a very big problem in our current society. Most patients are never told that the risk of getting cancer is 1/500 for children per CT scan and 1/1000 in adults. And a CTA (computer tomography angiographic) study is even worse at 3 times the amount of radiation. CT colonoscopy can be up to 4 times the radiation dose.

This is a 3-T MR editorial submitted by Dr Philip W Chao MD. His website www.3t-mri.net .
Dr Philip W Chao has worked in Delaware to produce the best MRIs possible since 1990. He has monitored hundreds of thousands of MRIs over his career at the University of Pennsylvania and working for the people of Delaware. He is a board certified neuroradiologist and recently passed his maintenance of certification examination in 2006. He is also trained in body MRI and was the body MRI fellow at the University of Pensylvania from 1988 through 1990.

Sunday, July 06, 2008

Primary Bone Lymphoma



This is case which was previously MRI to be infective, ATT started and no response was noted and lesions increased subesequently. It was not thought to be AVN as head has not collapsed. Acetabulum is normal. There is fluid along with soft tissue invasion and no periosteal response. All point to primary bone lymphoma -femur common site

Primary bone lymphoma is defined as a tumor involving a single focus with unequivocal evidence of lymphoma in the bone lesion. It is rare. Most cases are of the diffuse large B-cell category. The age distribution is bimodal with peaks in the second to third decade, and a second peak in the fifth to sixth decade with women more commonly affected in the older age group. There is a wide pattern of bone involvement with the spine forming the most frequent site of axial lesions, and the femur is the most common site overall.


Further reading
Appl Radiol 33(3):36-44, 2004.

Case by Dr MGK Murthy, Sr Consultant Radiologist

&

Dr.Sumer K Sethi, MD, Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers

Editor-in-chief, The Internet Journal of Radiology

Director, DAMS (Delhi Academy of Medical Sciences

Osteogenesis Imperfecta



At times a picture speaks louder than words...

Saturday, July 05, 2008

Acute Pyelonephritis


This a a young female presented with symptoms of urinary tract infection with CT shwoing bulky right kidney with inhomogenous striated nephrogram, likely acute pyelonephritis.


Central Pontine Myelinolysis


This is 19-month old girl with severe diahorrhea, MRI brain showing altered signal intensity in the central pons. Rarely reported in this age group but can be central pontine myelinolysis.

Dr.Sumer K Sethi, MD
Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers

Myositis Ossificans



Dr.Sumer K Sethi, MD
Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers
Editor-in-chief, The Internet Journal of Radiology
Director, DAMS (Delhi Academy of Medical Sciences

This is a post head injury follow up case shwoing myositis ossificans surrounding the hip joint.

Tuesday, July 01, 2008

Agenesis of the corpus callosum



A case of seizure disorder with partial agenesis (hypoplasia), the anterior portion (posterior genu and anterior body) is formed, but the posterior portion (posterior body and splenium) is not formed. The rostrum and the anterior/inferior genu are also not formed. Note the colpocephaly.

Dr.Sumer K Sethi, MD
Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers
Editor-in-chief, The Internet Journal of Radiology
Director, DAMS (Delhi Academy of Medical Sciences

Lymphocytic Hypophysitis-MRI



This is a case of histopathologically proved case of lymphocytic hypophysitis. MRI revealed enlargement of the pituitary gland and fossa, with traingular-dumbell shaped mass with significant heterogenous post contrast enhancement. There is suprasellar extension and alteration of the optic chiasm. Pituitary stalk cannot be identified.


Dr.Sumer K Sethi, MD
Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers

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