Onodi Cell-Mistaken as ICA Aneurysm

Onodi cell (sphenoethmoid air cell)

Case Submitted by Dr MGK Murthy, Mr Hari Om, Mr Venkat.

Edited by -Sumer Sethi, MD

·         Defined as ethmoidal air cell that lies posterior and sometimes superior to sphenoid sinus

·         Incidence in western world is usually 8 to 13%, though some studies give larger cadaveric incidence up to 60%

·         Optic nerve and Internal Carotid Artery  become closer than normal to  ethmoid air cells –point of concern to endoscopic sinus  surgeons

·         At places the bone separating them  is measured as mean 0.08mm. Infection may lead to mucocele

·         Occasionally could be mistaken for ICA aneurysm in view of the proximity to the loop and flow void nature on MRI. CT is usually adequate  to differentiate by presence of air density

Bifid Thumb-Plain Film

10 yr old child with history of injury , on X ray of the left hand shows an oblique   opacity in continuity with the 1^st Metacarpal with no separate epiphysis and suggestion of abnormal soft tisues in the region with stippled opacity at base of proximal phalanx. X ray of  the other hand shows  only soft tissue abnormality with no bony component. This possibly representative of Bifid Thumb (pre axial polydactyly) type of congenital hand anomalies.

Teaching points  by Dr MGK Murthy, Dr Sumer Sethi.

Duplication or polydactyly is common. Can be complete or partial

Bifid thumb occurs in  about 1 in 3000 births

Usually unilateral , but bilaterality is known. Cause is not known

Hand develops from Apical Ectodermal Ridge(AER)  around 3 to 8 weeks of gestation

Wassel classified the highly complex  hand anomalies as type I(Failure of formation),II(failure of differentiation),III(duplication), IV( overgrowth), Type V(undergrowth),type 6 (constriction band syndromes) and type 7(generalized anomalies and syndromes )

Can be 

·         just extra soft tissue not adherent to skeleton, devoid of bone, cartilage, joints or tendons (as in the non injured hand in our case )

·         digits may show duplication with components like bifid metacarpal (like our  case injured hand )or

·         there may be a complete digits formation with its own metacarpal.

Ellis van creveld syndrome is associated with bifid thumb

 Treatment is usually surgical and involves resection to avoid restriction of movements apart from cosmetic effect. Early surgery is defined as under 2 years and late is defined beyond that . Most surgeons prefer 2^nd year for surgery with good results 

Allow Breast Feeding After MRI-Contrast

According to an article by Jack Newman in Canadian Family Physician April 2007 vol. 53 no. 4 630-631- "Evidence indicates unequivocally that the contrast media used for both magnetic resonance imaging and computed tomography scans are excreted into breast milk in such small quantities that there is no concern at all for nursing babies. The contrast medium used for magnetic resonance imaging (MRI) scans is gadopentetate. It is excreted into breast milk in extremely small amounts.  Considering that we do MRI scans of small babies, concern about continuing breastfeeding after MRI makes no sense at all."

Tendoachilles Calcification-Plain Film

Two views always help for evaluation of any X-ray finding and localize to the site  of problem

Tendoachilles is the largest tendon in the body , spanning two joints and is subject to stress in daily activities (reaching upto 900kg in fast running at times ). Intense short use or prolonged overuse could result in degenerative changes of focal or diffuse variety leading to calcium deposition and is usually susceptible for rupture and degeneration 2-6 cms from site of insertion

Teaching points by Dr MGK Murthy. 

Morris etal classified calcification in to 3 types for management techniques

ü  type I-localised to tendon insertion and  posterosuperior aspect of calcaneum

ü  Type II-localised distal 1-3 cms of tendon

ü  Type III-Intratendinous and involves most of it(IIIA) and all of it (IIIB)

Excision before  other  complications like rupture and ulcerations and bone infection etc would be  preferred

X-ray true lateral  is ideal with MR playing complementary role in evaluating other soft tissue structures. Presurgical doppler  of  the posterior tibial  vessel is recommended 

Robotic Teleultrasound-Not Science Fiction

"Partners in the European MARTE (Mobile And Robotised Teleechography) project, in collaboration with ROBOSOFT have carried out the world's first robotised teleultrasound examination via satellite. This demonstration was accomplished with an ESTELE robot entirely controlled by robuBOX."

Femoral Neck-Aneurysmal Bone Cyst

22 year old male with history of fall and pain right hip. X-ray shows expansile lucent predominantly intramedullary, femoral neck lesion with normal hip joint. MR shows grossly expansile septated, predominantly fluid signal intensity space occupying lesion with cortical breaches, bleed, soft tissue edema in the vicinity – Features are suggestive of aneurysmal bone cyst.

Teaching Points by Dr MGK Murthy, contributors-Mr Hariom Sharma

ABC is non-neoplastic expansile lesion consisting of blood filled spaces separated by connective tissue septa containing bone or osteoid and osteoclast giant cells 

Etiology unknown 

May be primary or secondary ( in about 30 % of associated bone tumors).

CT suggests 20 HU as approximate density with presence of blood and fluid levels.

Double density fluid levels on MR are suggested as quite specific to ABC.

Differential diagnosis includes Simple Bone cyst (Centrally located with no expansion / cortical breach), GCT (more than 20 years of age, no significant expansion and predominantly epiphyseal lesion),  Osteoblastoma (usually diaphyseal, no fluid / fluid levels or cortical breach), Telengiectatic osteosarcoma / Angiosarcoma (difficult to differentiate from agressive ABC).

Escolta After Dark

Escolta, that old ephemeral street of Manila, has been one of my favorite hang-outs since I was a young Manila student in the early 1980s. Back then, I used to frequent this little boulevard to buy my long-playing discs in Syvel's (now closed), or to have my shoes cleaned by one of those ubiquitous shoeshine boys who lined the street sidewalks. Or perhaps just to hang-around in one of its old little cafés. I still visit the Escolta almost everyday, and every time, that wonderful and a little painful feeling of nostalgia is evoked in me.

I took the following photographs while on a solitary late-night walk along the old Escolta. I took these pictures just as souvenirs or perhaps to just record the scenes I have seen at a given time.

Evening newspapers. You can decide if they bear good news or bad.

Plaza Moraga

Night students

The old La Estrella del Norte building

Antique money seller

Pedestrians

Gone was the tranvia but the calesa still plies the Escolta

Posters and cables

Sidewalk-dwellers

Spinal Epidural Lymphoma- Review Article

Primary spinal epidural lymphoma (PSEL) is a subset of lymphomas, where there are no other recognizable sites

of lymphomas at the time of diagnosis.  The incidence of this subset of lymphomas is much less. It, however, is increasingly diagnosed, due to the increased use of more sensitive imaging modalities. 

Review article is now published with me as one of the contributors: Cugati G, Singh M, Pande A, Ramamurthi R, Balasubramanyam M, Sethi SK, et al. Primary spinal epidural lymphomas. J Craniovert Jun Spine 2011;2:3-11. Full free text is available.

Acute Cerebellitis-is it infectious or post infectious?

12 yr old boy had febrile episode of 5 days before developing seizures, and ataxia with altered sensorium and shows  on MRI,  an ill defined possibly” C “shaped , subtly enhancing  fluid signal intensity on all pulse sequences , of predominantly white matter regions  of posterior fossa, with more of vasogenic  rather than cytotoxic oedema ,  mass effect on 4^th ventricle, leading to  proximal hydrocephalus  and no bleed- picture suggestive of post infectious BRPINDs (Benign  Regressive  Post   Infectious Neurological  Disorders)

Teaching points by Dr MGK Murthy.  Contributors- Mr Hamid and  Mr Gupta

1.      Infectious edema  can be diagnosed by (a) short duration ,(b) gray matter as site of involvement,(c) decreased mental status  and (d) abnormal CSF, with post infectious exhibiting  opposites of these characteristics

2.      “C” shape is apparently on account of myelinating axons separating the areas of edema

3.      Post infectious demyelinating oedema is possible

4.      BRPINDs  usually exhibit good prognosis with no residual  disabilities

5.      These can be of ADEM variety where brain and cord are involved, or neuromyelitis optica where only optic nerves and cord are involved or only cerebellar variety (as in this case)

6.      MRI  is usually diagnostic  with CSF playing complementary role

7.      BRPINDs could be caused by bacterial/viral/vaccination (MMR)/drugs(arsenic, gold and sulfas etc)/Miscellaneous(herbal extracts etc)

Renal Sinus Tumor-MR urography

An adult male underwent USG check for left loin pain  with no hematuria. USG suggested a mixed echogenic mass for which enhanced CT showed heterogenous mildy enhancing mass in the renal sinus on left , possibly transitional cell carcinoma  with distorted collecting systems. MR urography has been advised in the light of this. It shows  a relatively  well defined complex mass lesion in the renal sinus location with stretched calyces and pelvis as such with no hydronephrosis or MR demonstrable calcification. It displays  relative bright signal on T1 and intermediate on T2 with heterogenous suppression on fat suppression. Inview of the above , mesenchymal origin  tumour lesions like fibroma are possible. Rest of  the  urography is normal

Teaching points by Dr MGK Murthy. Contributors Dr Krishna Mohan and Mr Laxman

1.Renal sinus  is perinephric space extension to deep recess on medial border of kidney

2. Has major artery/vein, major/minor collecting systems, adipose tissue/lymphatics/nerves of autonomic nervous system/varying degrees of fibrous tissue

3.Lesions are  defined as non tumorous  {lipomatosis/cysts/vascular orgin including aneurysms/fluid collections including urinomas  or extravasations}

And tumourous {renal pelvis(TCC)/mesenchymal origin(lipoma/fibroma etc)/renal parenchyma or retroperitoneal tumours projecting in to the region}

4.Parapelvic is usually referred to as alongside and peripelvic is defined as diffuse and all around the pelvis in terminology

5.USG is inadequate in tumors conditions and urography only shows sequelae

6.Coronal CT on MDCT technology is the ideal modality of choice with MRI including MR Urography playing a decisive role in  conflicting findings

7. 90%of renal pelvis tumors are Transitional cell carcinomas with 10% particularly in presence of calculus –squamous carcinoma and haematuria is  MUST

8.Mesenchymal  tumors include fibroma, hemangioma, leiomyoma, and angiomyolipoma and radiological  clue would be calyces stretching  with/ without  hydronephrosis

Multislice CT-The Modern Leonardo Da Vinci

Leonardo Da Vinci- drew many studies of the human skeleton and its parts, as well as muscles and sinews. He studied the mechanical functions of the skeleton and the muscular forces that are applied to it in a manner that prefigured the modern science of biomechanics.He drew the heart and vascular system, the sex organs and other internal organs, making one of the first scientific drawings of a fetus in utero. Look at this image taken from wikipedia and is a drawing of heart by Leonardo Da vinci and see how closely it resembles the Cardiac CT image, that is why, it may be appropiate to label multislice CT as modern Leonardo..

Tracheal Diverticulum-CT

67 year old smoker with shortness of breath shows: right paratracheal focal air cyst of approximately 3.2 cms length and 1 cm lumen with thin communication to the posterior tracheal wall with no cartilaginous rings. It suggests the uncommon tracheal diverticulum.

Teaching points by Dr MGK Murthy:

Paratracheal air cyst is a nonspecific term used for collection of air parallel to the trachea. Usually it occurs on the right in view of left side being occupied by esophagus.

Absense of alveoli excludes apical hernia or paraseptal bullae or blebs.

Barium swallow / oral contrast  would differentiate Zenker's diverticulum or pharyngocele. Extension from directly below the vocal cords would go in favour of laryngocele.

Presence of azygos fissure would occur along with azygos lobe.

Tracheal diverticulum can be 

a). congenital – possibly represents vestigial supernumerary  lung buds or aborted abnormal buds.

Lined by cartilages.

Small and narrow mouthed.

b). Acquired – Usually in smokers or chronic cough or expiratory obstructive air way diseases.

Majority at D2 level.

Size can varying.

Expand during forced expiration and decreased in inspiration.

Usually due to weakness in the posterior wall with pulmonary functions abnormality.

Lined by respiratory epithileum.

Mounier – Kuhn syndrome consists of multiple tracheal diverticula with marked dilatation of trachea and main bronchi with bronchiectasis and repeated lower respiratory tract infections.

3Tesla MRI- Article Published

Our article on 3 Tesla MRI in Neuroimaging was recently published in Imaging & Diagnostics magazine issue 3,  we are sharing the   link to the online version for our readers and peers here.

3Tesla MRI in Neuroimaging.

In House Radiologist versus Outsourcing

This eternal debate continues with Sep 2011 issue of Journal of the American College of Radiology, where authors talk of  value-added services by having radiologists in house: (1) patient safety, (2) quality of the images, (3) quality of the interpretations, (4) service to patients and referring physicians, (5) cost containment, and (6) helping build the hospital's business. 

 However, according to me, a mixed approach where in we have teleradiology complementing the inhouse team, by means of 1) vacation coverage,  2) added expertise for example we help one of our centres in cardiac CT and other in MSK MRI, 3) Peer Review , 4 ) Second opinions.

Placental Insufficiency & Diffusion-weighted Imaging

 Study published in December 2010 Radiology, 257, 810-819, suggests that placental dysfunction associated with growth restriction is associated with restricted diffusion and reduced ADC. Looks like another promising application of DWI in future.

Never Conclude Fractures on One Projection

The good old Radiographic principle revisited

Never conclude on one projection. Example by Dr MGK Murthy.

Patient with history of  fall

Frontal oblique apparently comfortable with soft tissue shadow  in the vicinity  of  fifth digit with  mild curvature of metacarpalin the region

Lo  behold!!

Do another projection and we have stippled pieces of bone in the vicinity of proximal row carpus possibly emanating from triquetral. Triquetral fractures are best seen on lateral radiograph and are due to  forced hyper flexion injuries  due to attachment of  Radiocarpal ligament

Remember acceptable  criterion for True lateral wrist

Radiograph for scapho –piso- capitate alignment -Ventral cortex of pisiform shows between ventral cortices of distal pole of scaphoid and head of capitate. Our X ray fits in to acceptable criterion (but not excellent) as pisiform is over the scaphoid almost completely

What do we do?

 We go for  MRI (to exclude extensor carpi ulnaris tendon and other soft tissue injuries apart from marrow edema delineation) and if necessary for MDCT after that

Whoever said Plain X rays are simple  with digital  technology

Radiology and Gulf war-Hippocampal Perfusion Dysfunction

Now in the latest issue of Radiology published online Sept. 13, researchers have found Gulf War veterans with specific syndromes, abnormal hippocampal blood flow persists, and in some cases worsens, 11 years after initial testing. War surely has long lasting effects.

Opercular Syndrome-MRI

10 year old male child comes with history of seizures with no significant birth history. MRI shows bilateral symmetrical FLAIR hyperintensities which are heterogeneous involving opercular regions with no restriced diffusion or blooming on SWI suggesting bilateral opercular syndrome.

Teaching points by Dr MGK Murthy :

Also called facio-labio-pharyngo-glosso-laryngeal and brachial paralysis or cortical variety of pseudo-bulbar-palsy or Foix – Chavany – Marie syndrome.

Five clinical types:
(a) the classical and most common form associated with cerebrovascular disease.
(b) a subacute form caused by CNS infections.
(c) a developmental form most often related to neuronal migration disorders.
(d) a reversible form in children with epilepsy.
(e) a rare type associated with neurodegenerative disorders.

Can be congenital or acquired, intermitant or persistent.

Characterised by a loss of voluntary control of facial, lingual, pharyngeal and masticatory muscles in the presence of preserved reflexive and automatic functions of the same muscles.

Cardiac CT/PET-will we take back cardiac imaging ultimately?

According to September 2011 RadioGraphics, 31, 1239-1254, edition where the authors predict the utility for cardiac PET/CT especially for coronary artery disease.  According to them, Hybrid PET–computed tomography scanners allow functional evaluation of myocardial perfusion combined with anatomic characterization of the epicardial coronary arteries, thereby offering great potential for both diagnosis and management.  Cardiac PET can be performed with an increasing variety of cyclotron- and generator-produced radiotracers. 

Making your Radiology Practice BIG

Key question

Brand creation versus Incentive based strategies.

Why is radiology business not such an easy business to create BRAND VALUE for consumers.

Image source-Wikipedia.

-          Patients are consumers but not the deciding factor in RADIOLOGY. Referring physician decides.

-          His decision is not only based on EXPERTISE but also on incentive and personal relationships.

-          Still Pathology labs have done it in past, is it possible in Radiology?

-          Teleradiology is bound to become the basis of common brand creation in radiology centre chain

-          Sonographers will be required as getting radiologists to do the ultrasounds is getting tougher by the day. Sonographers should do the USG and radiologist should interpret the images.

-          Some corporate chains are already working on acquiring existing centres and creating common platform.

-          There is definite role for entrepreneurs in this field in times to come for sure. Running an ultrasound centre in your locality is NOT entrepreneurship. What are your thoughts on this topic? All comments are welcome.

Dengue Hemorrhagic Fever-MRI

32 yr adult with clinical and serology positive Dengue fever with acute encephalopathy with low platelet  counts   shows on CEMRI, multiple hemorrhagic   focal lesions in supra and infratentorial locations with relative sparing of basal ganglia and brainstem and varying degrees of  restriction and enhancement ,   possibly explained by different ages of bleed and  therefore varying  degrees  of breakdown of blood brain barrier

Questions in the case

1. Thalami spared?---   variations are reported

2. Enhancement is varied  in different lesions? possibly  related to  different ages of  bleed

3. Meninges normal--  Imaging  is not good  enough for meningitis

4. Cord is normal?--- encephalomyelitis is only  known to occur in some

5. Is comorbidity possible with some other infections?—certainly possible, but since serology and CSF are negative, less likely

Teaching points  for Radiologist  by Dr MGK Murthy. Images by Mr Hariom and Mr Venkat.

·         Dengue fever occurs in about 100 countries ,and is caused by RNA virus of Flavivirdae family

·          Non-neurotropic nature of the virus is now questioned with some  growing from CSF

·         Neurology involvement can be encephalitis (direct virus effects) or more common encephalopathy (usually metabolic, hypotension or haemorrhage  related findings)

·         CSF serology an virus culture are considered as gold standard

·         MRI plays crucial role in altered sensorium patients to  exclude  other causes  as well  show focal lesions apart from  severity and nature

·         Viral encephalitides have predilection for certain sites as below :

HSV: Frontal, Temporal lobes

Japanese Encephalaitis: Thalamus, basal ganglia, cerebellum, brainstem

West Nile fever: Deep grey matter, mesial temporal lobe, cerebellum, brainstem. Difficult to differentiate from JE on imaging alone

Rabies: Hippocampi, basal ganglia, brainstem , temporal lobes.

Chikungunya: cingulated gyrus, Limbic system

Nipah: multiple white matter lesions.

Cardiac decompensation-CXR

Elderly person with shortness of breath what is the finding?

There is big heart and generally ill-defined lung fields. On closer examination,  we notice, upper lobar vessels are around 3mm(normal maximum of 2mm) called cephalization has occurred. There are few areas of peribronchial cuffing i.e. there is interstitial fluid accumulated around the bronchi  making them look like doughnuts . Both perihilar regions are hazy and ill-defined suggesting fluid. The appearance  is  classical of  cardiac decompensation.

Teaching points by Dr MGK Murthy

·         Left atrial pressure measure is quite represented by X ray appearance. Normal being 5-10 mm Hg, cephalization(10-15),Kerley B lines (15-20),interstitial edema(20-25), an alveolar edema(>25mm Hg)

·         Kerley B lines are 1-2 cms long horizontal bases  lines  and are perpendicular to pleural surface

·         Pulmonary oedema usually clears in about 3days or less. Clearance is usually from periphery to center(because of  emptying effect of breathing and movement )

·         Unilateral oedema may be seen in dependent side if patient lies on one side overnight. Normal vessel to bronchus ratio is upper lobes(0.85), at hila(1.0) and lower lobes (1.35).

Trachea on CXR-Patient with Stridor

What are the findings in elderly male with  history of  wheezing?

Tracheal lumen despite malrotation and flexion of the neck looks abnormal focally in thoracic segment. The others include curvilinear calcification at the left heart border with no significant cardiomegaly along with left costopleural opacity

How do we explain and what is the important finding?

It is difficult to pinpoint extent of severity of individual findings in this patient at this time. However as the  patient has reported for wheezing with possible expiratory stridor, I would suggest we concentrate on Trachea and ask for direct/ indirect tracheoscopy , fluoroscopy to see post wall collapse or CT chest or simply good lateral view and follow up  x- rays ( if clinical situation permits)

Teaching points by Dr MGK Murthy, Resident-Professor Series.

·         Trachea extends  from cricoid(C6) to carina with inferior end dynamic and changes with inspiration/expiration coming up to D6 at times

·         PA of Chest and true lateral with head hyperextended with high KVp(to get less of white bony thorax) are ideal. Unusual flexion of the neck specially in children produces buckled appearance (pseudomass )

·         Triad of  Anterior buckling of posterior tracheal wall, narrow AP dimension, and widened posterior membranous tracheal wall clinch tracheomalacia as diagnosis(fluoroscopy will help see unusual  expiratory collapse)

·          The other uncommon  causes are usually pappillomatosis, leiomyoma, schwannoma, paraganglioma, melanoma, carcinoma and sarcomas(1 true tracheal tumor for every 140 bronchogenic carcinomas estimated )

·         CT particularly in inspiration/ expiration is the imaging modality of choice

what about the heart and pleura in this case?

Incidental aneurysms in elderly age(this patient is 93 yrs old ) need echo correlation for evaluation and pleural thickening needs no follow up