Bilateral symmetric medial temporal calcification

Clinical Details  : First of two sibs born of non consanguineous marriage, full term cesarean birth
Reportedly had meconium aspiration, neck holding about 9 month sitting somewhat at the age of one year, started walking with difficulty at one and half years and even now there is no speech
Suffered a febrile seizure at the age of one year.
Presently on phenytoin 3.5ml BID
Can walk independently but very clumsily.
No abnormal posturing.
Previous CT reports multiple areas of calcification, evaluated for TORCH infection.
EEG was reported normal.

CT brain shows bilateral symmetric medial temporal horn like calcification.
Bilateral parietal white matter hypo density due to abnormal myelination.

Impression:

Lipoid proteinosis is a rare diagnosis suggested imaging wise, though there is no associated blephritis at present on clinical examination.
This can not be TORCH sequel as medial temporal horn like calcification is bilateral and symmetric.

Similar Case of Lipoid Proteinosis : Click here

Lipoid proteinosis

Syn : Urbach-Wiethe disease, initially described by Urbach and Wiethe in 1929 as “hyalinosis cutis et mucosae”.
A rare genodermatosis characterized by multisystem involvement due to intracellular deposition of an amorphous hyaline material.
Caused by mutations in the ECM1 gene on chromosome 1q21.
Normally EMC1 gene is expressed in the dermis, basal keratinocytes, endothelial cells and developing bones and is linked to keratinocyte differentiation, basement membrane regulation, collagen composition, and growth-factor binding. The mutated ECM1 gene gives rise to hyaline material deposition in the dermis and thickening of the skin and mucous basement membrane around blood vessels and adnexal epithelia.
The patient may present with abnormal scarring and wound healing. Premature skin aging, skin and mucosal thickening usually the first clinical manifestation. Moniliform blepharosis is considered a pathognomonic finding present in 50% of patients.

Associated hoarseness is present at birth or in the early infancy in two-thirds of patients, due to early hyaline material larynx infiltration, progressing with time.

When CNS is affected, a wide variety of neurologic abnormalities may be present. The hallmark findings are calcifications, mostly occurring in the amygdalae, hippocampus, parahippocampal gyrus, or even the striatum.
CNS infiltration occurs predominantly around the hippocampal capillaries, resulting in wall thickening, which later progresses to perivascular calcium deposition.
Neurologic manifestations range from migraine, variable degrees of mental retardation, seizures, depression, anxiety, and panic attacks to disturbances in decision making, memory, and abnormal social interaction patterns.

In half of cases imaging assist in the diagnosis and gives clue to the diagnosis because there are few diseases that can manifest such a typical pattern of bilateral and symmetrical calcification occurring in the medial temporal lobes. Amygdalae involvement is considered pathognomonic.
The other commonly affected sites are the amygdalae, hippocampus, parahippocampal gyrus, or even the striatum. The calcification pattern described is dense curvilinear horn-shaped well depicted by CT in the amygdaloid bodies. In MR imaging, such lesions are hypointense in all pulse sequences, especially in GRE T2*

Reference : American journal of Neuroradiology, Amygdalae and Striatum Calcification in Lipoid Proteinosis F.G. Gonçalvesa,b, M.B. de Meloa,  V. de L. Matosa, F.R. Barraa and R.E. Figueroac.

A focal Vermian bleed on MRI

 

MRI BRAIN WITH CONTRAST REPORT

This MRI study of brain reveals an ~ 12x13mm well defined round to ovoid nodular lesion in cerebellar vermis at the roof of fourth ventricle. Lesion is bright on T1 with high signal on T2 suggestive of blood degradation product with low signal on GRE. No marked peri lesional odema. No significant mass effect or mid line shift.

Imaging wise diagnosis suggested was Tumor nodule with bleed, however possibility of underlying vascular malformation can not be ruled out on imaging.

Operated with posterior fossa craniotomy. E/o complete excision of lesion on post operative scans. No major extra / intra axial bleed.

REPORT OF HISTO PATHOLOGICAL EXAMINATION

Specimen         : Excisional biopsy – SOL in base of skull (cerebellar vermis). 
Gross Appearance    : The specimen consists of few irregular soft pieces of dull greyish white tissue; together measuring 0.3X0.3X0.2 cm. The entire tissue is submitted for processing.    

Microscopy        : Section and additional made serial deeper section shows fragmented bits of reactive cerebellar tissue with the central portion showing ectatic vascular channel with undulating wall, devoid of smooth muscle and elastic lamellae. Also seen are couple of fragments with microhaemorrhage and scattered haemosiderophages along with prominent perivascular lymphocytic cuffing. There is no evidence of malignancy. 

Final Diagnosis  : Bleed secondary to Cavernous Angioma (Cavernoma).

Medulloblastoma MRI

Clinical Details  : From last one and half months has tremolousness involving left arm, episodic associated with facial twitching, unsteadiness of gait and severe headaches associated with vomiting. No significant illness in the past. Examination shows bilateral papilloedema, brisk reflexes, plantars flexor.

MRI BRAIN WITH CONTRAST REPORT
MR study of brain reveals an ~ 35x37mm well defined solid signal intensity tumor in the region of fourth ventricle causing moderate obstructive hydrocephalous, peri ventricular ooze of Csf. Diffuse cerebral odema. Prominent Sub Arachnoid space around optic nerves owing to raised ICT.
Cysts noted at the periphery of lesion, solid component show mild patchy enhancement on post contrast, restricted diffusion on Dw images.

Imaging wise primary diagnosis : Medulloblastoma.
No DDs suggested.  

Operated with posterior fossa craniotomy. E/o complete excision of lesion. No major intra / extra axial bleed.
And here is...

REPORT OF HISTOPATHOLOGICAL EXAMINATION

Specimen         :     Biopsy – 4th ventricular SOL.
Gross Appearance    :     The specimen consists of few soft to friable fragments of dull grey-white tissue; together measuring 3.0X2.5X1.3 cm. The entire tissue is submitted for processing.
Codes : A and B.

Microscopy        :     Sections A and B both show fragmented bits of monotonous undifferentiated cellular neoplasm of probable medulloblastic origin. The tumour consists of cohesive sheets of fairly monotonous appearing, intermediate sized, round to oval cells having hyperchromatic, minimally pleomorphic nuclei with coarse chromatin and scanty eosinophilic cytoplasm. Few foci reveal nuclear moulding, while many areas show elongation of nuclei. The neoplasm in couple of foci show vague nodular configuration with nodules comprising of rather pale-stained neoplastic cells. The interstitium at places appears desmoplastic and shows compressed congested blood vessels. An occasional focus shows mitosis. No classical               Homer-Wright rosettes seen. The background shows minimal fibrillary appearance. Also seen are couple of fragments of cerebellar parenchyma.

Final Diagnosis :  Embryonal malignant small blue cell tumor – Medulloblastoma; undifferentiated.

Adv. :     Ancillary IHC studies are mandatory for confirmation and definite lineage typing.

Similar Cases
1. http://www.neuroradiologycases.com/2011/08/medulloblastoma.html
2. http://www.neuroradiologycases.com/2011/11/medulloblastoma-mr-spectroscopy.html
3. http://www.neuroradiologycases.com/2012/01/medullobastoma-cerebellar-lateral.html

MEDULLOBLASTOMA

Syn: MB, Posterior fossa PNET, PNET – MB,
A highly cellular embryonal cell tumor.
Age group : common in children, ~75% diagnosed by 10 years.
3 times more common in males.

Location:
Intraventricular – 4th ventricular roof is a typical and most common location. A most common posterior fossa tumour in children.
Lateral origin – Cerebellar hemisphere is an atypical location common in older children and adults.

Size vary, average size ranges between 3- 5cm at the time of presentation.
On Non contrast CT, solid 4th ventricle mass, hyperdense, calcifcaiton seen in ~20% cases, small intra tumoural cysts, necrosis in ~50% cases.
On MR signal on T1 iso - hypo intense to cortical grey matter on T1 , iso – hyperintense on T2w and FLAIR. High signal on diffusion attributed to its dense, highly cellular nature.
An associated Obstructive hydrocephalus is common seen in ~ 95% cases.
Usually mild to moderate and homogenous enhancement, may show patchy heterogeneous enhancement due to areas of necrosis.
On MR Spectroscopy, NAA reduced or absent as it’s a non neuronal tumour, raised choline.

Cerebellar avid enhancing nodule on MRI

 

 

A 27 yo female patient with giddiness.

MRI brain with contrast shows an avid discoid enhancing intra axial left cerebellar tumor nodule with marked peri lesional odema. No cystic or necrotic component. An adjacent tortuous vessel noted implying its vascular supply. No bleed or calcification. No restricted diffusion on Dw images.

Histopathology Report

Gross appearance : soft to friable dull gray tan tissue, cut section was dark browh with hemorrhagic appearance.

Microscopy: modedrately vascular neoplasm, partially surrounded by pilocystic gliosis. Neoplasm consist of both cellular and reticular areas comprising of numerus proliferating vascular channels of varying caliber, majority of them being congested with few appearing ecstatic. The interstitium shows scattered round to oval cells having modestly hyper chromatin nuclei with coarse chromatin and abundant eosinophilic to vacuolated cytoplasm. These cells have indistinct cytoplasmic margins. No atypical mitosis nor tumor necrosis seen.

Final Diagnosis: Hemangioblastoma.

Cerebellar hemangioblastoma is a benign neoplasm of uncertain origin that comprises approximately 7% of posterior fossa tumors in adults. It is the most common primary intra axial neoplasm of the adult posterior fossa.

The association between hemangioblastoma and von Hippel-Lindau syndrome has been well documented, ranged from 35% to 60% in the literature.
Age, peaks in incidence during the fifth and sixth decades, except in von Hippel-Lindau syndrome, in which they present in younger adults.
Location, the cerebellum is most frequent site, but can also be found in medulla or within the spinal cord, particularly in von Hippel-Lindau syndrome. Supratentorial hemangioblastoma is exceptionally rare.
Usually solitary lesions; multiplicity is said to occur in 20% of von Hippel-Lindau syndrome and only rarely in otherwise healthy patients. Multiple hemangioblastomas are more common in spinal cord.
Gross pathologic examination of hemangioblastomas reveals well-demarcated, frequently cystic masses with highly vascularized solid nodules within the wall of the cyst. Aside from the mural nodule, the cyst wall is not involved with tumor but is more often simply gliotic.

Microscopically, the tumor is neither encapsulated nor well circumscribed, and it can invade cerebellar parenchyma. Intratumoral hemorrhage can occur occasionally in association with hemangioblastoma. The mural nodule is a hypervascular mass of capillaries with intervening benign-appearing neoplastic stroma.

Surgical resection is considered curative, but recurrence is common after incomplete excision. In fact, after complete surgical excision, recurrent lesions may actually represent new lesions in von Hippel-Lindau syndrome.

MR imaging is the most effective noninvasive imaging modality. There are several characteristic findings on MR imaging that, when found in conjunction with each other, are virtually pathognomonic for this lesion and should be sought by the neuroradiologist in the presence of any intra axial posterior fossa mass in an adult. The most important of these include the following: (a) the cystic nature of the mass, (b) a peripheral pial-based mural nodule of solid tissue that enhances markedly with intravenous contrast, and (c) large vessels within and/or at the periphery of the mass.

Approximately two thirds of cerebellar hemangioblastomas are at least partially cystic. Hemangioblastoma cysts are sharply marginated and have smooth borders, signal intensity of tumor cysts is somewhat variable. Entirely solid hemangioblastomas occur in 30% to 40% of cases and are the most common morphologic type if in the supratentorial compartment.

The mural nodule or solid portion of the tumor is usually only slightly hyperintense or isointense to gray matter on T2-weighted images and always densely enhances with intravenous contrast and should abut the pia. Although not typical, the cyst wall may also enhance, despite being nonneoplastic. The third feature of hemangioblastomas is the presence of large associated vessels.
Tumor vessels are depicted as serpentine or linear regions of signal void on spin echo images.
In patients with von Hippel-Lindau disease, the presence of multiple enhancing lesions of varying sizes in the cerebellum is pathognomonic for hemangioblastomas.


(Reference : Atlas, Scott W, Magnetic Resonance Imaging of the Brain and Spine, 4th Edition)

Bilateral Mesial Temporal Sclerosis MRI

Coronal high resolution T2 and FLAIR are best to diagnose MTS.

Findings include reduced hippocampal volume that is hippocampal atrophy, increased T2 signal, abnormal morphology that is loss of internal architecture and interdigitations of hippocampus.

Although comparing with opposite is easiest, it must be remembered that up to 10% of cases are bilateral, and thus if symmetry is the only feature being evaluated, many cases may be misinterpreted as normal.

Often mentioned, but probably one of the least specific findings, is enlargement of the temporal horn of the lateral ventricle. If anything, care must be taken to not allow an enlarged horn to trick you to over diagnosis as hippocampal atrophy.

Lateral epipharyngeal cyst MRI

Cystic lesion in the right pharyngeal recess (fossa of Rosenmüller), behind the paryngeal ostium of the Eustachian tube.

Spinal Epidermoid cyst MRI

Clinically: A 30 y o male with neurogenic bladder. 

Findings:

This MRI lumbar spine show a spinal intra dural cystic signal intensity well defined lesion hypo intense on T1, hyper intense on T2 with restricted diffusion on Dw images. 

An associated expansion and scalloping of bony spinal canal. 

Lesion is confined to spinal canal and not extending out of neural foramen. 

Lesion is non enhancing on post contrast, except thin rim of enhancement on post contrast T1. 

Imaging diagnosis : Spinal Epidermoid Cyst.

Urinary bladder show diffuse wall thickening, irregularity with trabeculations attributed to associated Neurogenic bladder. 

Spinal Epidermoid Cyst

They are usually extra medullary but rarely can be intra medullary. They may be congenital or acquired.
Spinal epidermoid cysts are uncommon.

Unlike intracranial epidermoid cysts, which are almost always congenital in origin, most of spinal epidermoid cysts are acquired. Although present since birth, congenital epidermoid tumours often do not present until the second to fourth decade of life.
Males are more commonly affected than females.

Spinal epidermoid cysts may asymptomatic and discovered incidentally. If symptomatic, motor disturbances, pain, sensory disturbances, and bowel or bladder dysfunction may be present.
Congenital spinal epidermoids result from anomalous implantation of ectodermal cells during closure of the neural tube between the third and fifth week of embryonic life.
Acquired spinal epidermoids are a late complication of lumbar puncture, resulting from implanted epidermal elements into the spinal canal. The time interval between lumbar puncture and tumour diagnosis ranges from 1 to more than 20 years. Acquired spinal epidermoids are generally extramedullary and situated near a vertebral interspace.

Congenital epidermoids usually occur at the conus or cauda equina. Acquired cysts are found in the lower lumbar region.
Epidermoid cysts are commonly associated with spinal malformations such as spina bifida and hemivertebrae.

On CT, a well circumscribed mass, hypodense (similar to CSF),  minimal to no enhancement on post contrast, calcification is rare. Associated osseous changes include an expanded spinal canal, laminar thinning and vertebral body scalloping. 

On MRI typical signal characteristics include hypointense (similar to CSF) on T1, hyperintense (similar to CSF) on T2 and slightly hyperintense compared to CSF on FLAIR due to incomplete signal suppression. On T1 C+ (Gd) no enhancement or a thin rim of capsular enhancement. Characteristic bright signal on Diffusion with corresponding low intensity on ADC map. Signal intensity may be homogeneous or heterogeneous according to the variable water, lipid and protein composition of the cyst.

Spinal epidermoid cysts are slow growing.
Surgery is the treatment of choice, complete excision.
If the cyst wall is tightly adherent to the cord parenchyma, the wall should be left in place, however this leads to a risk of recurrence.

Differential diagnosis include spinal arachnoid cyst which lacks brightness of restricted diffusion on DWI, complete signal suppression on FLAIR. Vertebral anomalies uncommon.
Spinal dermoid cyst usually contains fatty elements, less likely to demonstrate diffusion restriction on DWI, patients are usually younger than 20 years of age.
Spinal neurenteric cyst common in thoracic and cervical regions, ventral to spinal cord with associated vertebral anomalies. 

AVM with bleed and ischemic complications on MRI

Clinical Details  : Two months ago suffered from a left basal ganglionic bleed. Had to have decompression done. PResently has a power of grade 0 on the right arm and right leg but speech is fairly well preserved. 

Presently on Ecosprin gold, Omnacortil. Pantocard.

Advised MRI for better evaluation

MRI Brain with MR Angiography of Brain Report

Sequences planned are FLAIR, T2w*GRE and DW images.

Non Contrast Enhanced intracranial Angio performed with 3D TOF and Neck Angio performed with 2D TOF sequence. The study viewed in row as well as 3D reconstructed images.

A focal Gliosis  with hemosiderin staining on GRE involving left thalamus, adjacent basal ganglia, insula and temporal lobe_ Chronic resolved hematoma with areas of chronic ischemic infarcts in left MCA cortical branches territory. 

An associated changes of distal wallerian degeneration on left side. 

An obvious high flow vascular malformation _ AVM noted, left pcom appears to be the feeder. 

Sparisty of cortical branches of left MCA. 

Rest of the both intra cranial as well as extra cranial vessels show normal flow related signals on 3D reconstructed images of Non Enhanced 3D TOF and 2D TOF sequences.

Impression: 

Chronic resolved hematoma with chronic infarcts in left MCA cortical branches territory.

An obvious high flow vascular malformation / AVM noted, left pcom appears to be the feeder. 

Sparisty of cortical branches of left MCA compared to right.

Needs DSA for better evaluation / confirmation. 

Atypical Trigeminal Neuralgia MRI

Clinical details: right side trigeminal neuralgia.

MRI BRAIN FOR TRIGEMINAL NERVES

Multi planner multi echo MRI study of brain has been performed. Sequences planned are FSE T1W, FSE T2W, FLAIR, T2w *GRE and DW images. FIESTA for cranial nerves.
Pc t1

This MRI Brain shows:
Abnormal T2 hyper intensity in right half of Pons at the entry point of right side trigemninal nerve, and adjacent right side trigeminal nerve_ significant for patients clinical complaints.
There is faint high signal on DW images in corresponding region.
No abnormal enhancement on post contrast T1.

Possibilities given were Demyelination, Ischemia.

He was prescribed
Amytryptiline 25 mg HS
Wyselon 20mg daily for 5 days, 10 mg for next 5 day and then stop
Gabapentine 300mg BD

During follow up after 2 weeks
He was clinically improved by 75 % which goes in favor of Demyelination.
During this follow up, MRI imaging shows lesion is same in size without any significant change on T2w images. The faint hyper intensity which was seen in previous MRI was reduced.
Advised further follow up imaging.

Current clinical status after 2 months, 100% improved.

There are persuasive evidences that trigeminal neuralgia is usually caused by demyelination of trigeminal sensory fibres within either the nerve root or, less commonly, the brainstem at the entry point of nerve. However in most cases, the trigeminal nerve root demyelination involves the proximal, CNS part of the root and results from compression by an overlying artery or vein.

Unilateral Optic Nerve Aplasia

Clinically a premature baby, Ophthamological evaluation revealed abnormally small Optic disc on right side. Advised MRI for further evaluation. 

MRI brain shows absent right side optic nerve, its intra cranial as well as intra orbital portion.
Left side optic nerve normal in caliber and signals, left half of optic chiasm and bilateral optic tracts normal. No associated anomalies of corpus callosum or septum pellucidum. Pituitary gland normal, no posterior lobe ectopia.

Impression: Congenital Unilateral Optic Nerve Aplasia.

Optic Nerve Aplasia 

A rare developmental anomaly characterized by the congenital absence of the optic nerve, central retinal vessels and retinal ganglion cells.
Aplasia is often unilateral, generally associated with otherwise normal brain development while bilateral optic nerve aplasia is usually accompanied by severe and widespread CNS malformations.
The pathogenesis of optic nerve aplasia may be due to defective formation of the embryonal fissure, failure of the mesenchymal anlage of the hyaloid system to enter the embryonal fissure, or primary agenesis of the retinal ganglion cells.

Optic nerve hypoplasia is seen ophthalmoscopically as an abnormally small optic nerve head. A peripapillary ring around a small optic disc is the hallmark, but is not always present. ONH may be associated with tortuosity of the retinal vasculature. A relative afferent pupil defect adds weight to the diagnosis.

ONH is commonly asymptomatic and may first be detected by identification of visual field loss or observation of the optic nerve head.

Associations,
1. Isolated ONH.
2. Absent septum pellucidum.
3. Posterior pituitary ectopia (commonly associated with endocrine dysfunction).
4. Migrational anomalies in the cerebral hemispheres (for example, thinning of the corpus callosum, which is predictive of neurodevelopmental problems). Other associated brain abnormalities include porencephaly, schizencephaly, intracranial arachnoid cyst, and intracranial epidermoid cyst.

Septo-optic dysplasia comprise any combination of ONH, pituitary gland hypoplasia, and midline abnormalities of the brain. Recent studies have shown that in SOD, key mutations have been identified in Hesx-1, a protein that is involved in the mediation of normal development of the forebrain and the eyes during embryogenesis.