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KEY FACTS

Terminology
- Facial nerve schwannoma (FNS): Rare, benign tumor of Schwann cells that surround CNVII in CPA-IAC ± labyrinthine CNVII
Imaging
- Temporal bone CT findings - Smoothly widened facial canal without destruction
- MR findings - T1 C+ MR: CPA-IAC-facial canal enhancing mass
Top Differential Diagnoses
- Bell palsy (herpetic facial paralysis)
- Vestibular schwannoma
- CPA-IAC meningioma
Pathology
- Tumor of Schwann cells lining CNVII, usually sporadic
- Neurofibromatosis type 2 - Bilateral CPA-IAC schwannomas - May be of vestibular or facial nerve origin
Clinical Issues
- Clinical presentation - Sensorineural hearing loss (SNHL) if CPA-IAC - Facial nerve paralysis &/or conductive hearing loss if tympanic segment involved - SNHL & facial nerve paralysis similar in frequency
- Treatment options - Conservative management: Do nothing until CNVII paralysis present - Surgical management: Used when CNVII paralysis + other symptoms evolving - Debulking also effective - Stereotactic radiosurgery - Used for poor surgical candidates - Recent use in small- to medium-sized FNS with CNVII function & hearing relatively preserved

TERMINOLOGY

Abbreviations
- Facial nerve schwannoma (FNS)
Synonyms
- Facial neuroma, facial neurilemmoma
Definitions
- FNS: Rare, benign tumor of Schwann cells that surround facial nerve in cerebellopontine angle (CPA)-internal auditory canal (IAC)

IMAGING

General Features

Best diagnostic clue

- CPA-IAC mass + **tail in labyrinthine CNVII canal**

Location

- CPA-IAC & labyrinthine segment of CNVII canal
- Geniculate ganglion & tympanic segments most commonly involved in temporal bone

Size

- Wide range from millimeters to centimeters

Morphology

- Large: CPA-IAC ice cream on cone shape with comma-shaped tail in labyrinthine segment CNVII
- Small: IAC mass curves into labyrinthine tail (may be in IAC CNVII only mimicking vestibular schwannoma)

CT Findings

Bone CT

- ↑ size labyrinthine CNVII canal ± geniculate fossa
- Requires high-resolution temporal bone CT technique

MR Findings
- T1WI C+
```
- CPA-IAC-labyrinthine canal enhancing mass
        - ± **intramural cystic change**
```
- CISS, FIESTA, T2 SPACE - FNS CPA-IAC = low-signal mass displaces CSF signal

Imaging Recommendations

Best imaging tool

- CNVII or CNVIII symptoms 1st study with T1 C+ FS MR
        - Axial ≤ 3-mm T1 C+ MR; axial & coronal of CPA-IAC
- Bone CT: Smooth, scalloped widening of facial canal without destructive changes
- Coregistering 3D T1 C+ MR and temporal bone CT may improve diagnosis & surgical planning

DIFFERENTIAL DIAGNOSIS

Bell Palsy (Herpetic Facial Paralysis)
- T1 C+ MR: Prominent enhancement of intratemporal CNVII with IAC fundal tuft of enhancement
Vestibular Schwannoma
- T1 C+ MR: CPA-IAC enhancing mass without labyrinthine canal tail or other facial canal involvement
CPA-IAC Meningioma
- T1 C+ MR: Dural-based, eccentric CPA enhancing mass with dural tail projecting into IAC

PATHOLOGY

General Features

Etiology

- Tumor of Schwann cells investing CNVII
- Most often sporadic

Genetics

- Multiple schwannomas = neurofibromatosis 2 (NF2)

Associated abnormalities

- **NF2:**Bilateral vestibular schwannoma; other CN schwannoma, meningiomas also seen

Gross Pathologic & Surgical Features
- Tan, ovoid-tubular, encapsulated mass
- From outer nerve sheath layer
Microscopic Features
- Encapsulated; bundles of spindle-shaped Schwann cells forming whorled pattern
- Cellular architecture: Densely cellular (Antoni A) areas ± loose, myxomatous (Antoni B) areas

CLINICAL ISSUES

Presentation

Most common signs/symptoms

- Transient or persistent facial palsy is most common symptom, followed by hearing loss
        - IAC or CPA FNS cause sensorineural hearing loss
        - Tympanic segment FNS tend to cause facial palsy &/or conductive hearing loss
- Other symptoms: Vertigo, hemifacial spasm

Demographics

Age

- Average age at presentation: ~ **50 years**
- Unless neurofibromatosis type 2 present; younger group

Epidemiology

- Rare tumor (CPA-IAC > temporal bone > parotid)

Natural History & Prognosis
- CNVII paralysis takes years to develop
- Surgical cure can be worse than disease
Treatment
- Conservative: Do nothing until CNVII paralysis present - Some do not grow; some never become symptomatic
- Surgery when CNVII paralysis + other symptoms evolving - Goal: Complete tumor removal + preservation of hearing & restoration of CNVII function - Debulking procedure is alternative approach - Early indications: ↓ CNVII loss of function without significant recurrence rates
- Stereotactic radiosurgery - Primary treatment for small- to medium-sized FNS when CNVII function & hearing relatively preserved

DIAGNOSTIC CHECKLIST

Consider
- Thin-section imaging shows labyrinthine tail
Image Interpretation Pearls
- CPA-IAC FNS exactly mimics vestibular schwannoma if no labyrinthine tail or temporal bone component present

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References

Selected References

Cases

{'cases': [{'authors': [{'key': '6651ae1c-5f55-4d2e-9f68-46223037c90a', 'value': ' , '}], 'caseVersionId': 'f99106f0-6076-48ae-a670-6435e6de529e', 'description': 'Facial nerve schwannoma in fundus of IAC with subtle labyrinthine segment "tail" on high-resolution thin-section T2 MR images.\n\nAxial T2 images (#1-3) show a tissue-intensity ovoid mass in the fundus of the IAC (arrow). First impression is that of a fundal acoustic schwannoma. However, on images 2 & 3, the labyrinthine segment facial nerve "tail" (open arrow) suggests the correct diagnosis of facial nerve schwannoma. \n\nSagittal T2 MR images from medial to lateral (#4-7) show the tumor above the crista falciformis (curved arrow, #5 image), then extending out along the labyrinthine segment of the facial nerve (open arrows, images 6 & 7). \n\nComment: It is imperative that the radiologist look for a "labyrinthine tail" on all fundal acoustic schwannomas. A small percentage (< 1%) will be IAC facial nerve schwannomas and must be recognized in the pre-operative period.', 'history': 'Patient with 5 year history of mild right facial nerve paresis and moderate sensorineural hearing loss.', 'imagePoolId': '8ef26e9d-8d7f-4e7f-8cea-8a038945e9ab', 'name': 'Small, fundal', 'teachingPoint': None, 'demographics': '42 Years old female'}, {'authors': [{'key': '6651ae1c-5f55-4d2e-9f68-46223037c90a', 'value': ' , '}], 'caseVersionId': '1a7a64dc-b87e-4dd2-8874-860e979bb625', 'description': 'CPA-IAC facial nerve schwannoma extending to involve labyrinthine segment and geniculate ganglion of intratemporal facial nerve.\n\nAxial CECT (#1) shows a CPA enhancing mass (arrow) at first thought to represent acoustic schwannoma. After this exam a temporal bone CT was ordered because of history of mild facial nerve paresis. T-bone CT (#2) shows enlargement of labyrinthine segment of facial nerve and the geniculate fossa on the right (open arrow). In addition, the normal left labyrinthine segment of CN7 is seen (curved arrow). Coronal right T-bone CT (#3) reveals enlarged geniculate fossa (open arrow). Image #4 is included to show the size of the normal left labyrinthine segment (curved arrow).\n\nTwo unenhanced T1 axial MR images of the right CPA demonstrate the CPA component of the facial nerve schwannoma (arrow) with a labyrinthine "tail" (open arrow) arising from the medial IAC.\n\nComment: Acoustic schwannoma rarely causes facial nerve injury even when very large. For a lesion this size to cause facial nerve symptoms would be exceedingly rare. It is therefore recommended that if the history is that of combined sensorineural hearing loss and facial nerve symptoms, temporal bone CT be done to look for enlargement of the labyrinthine segment of the facial nerve canal. If enlarged, facial nerve schwannoma is present.', 'history': 'Patient with right sensorineural hearing loss with mild right facial nerve paresis.', 'imagePoolId': '4e830916-6460-4146-b578-32db31941850', 'name': 'Medium sized', 'teachingPoint': None, 'demographics': '46 Years old female'}, {'authors': [{'key': '33151213-01b2-4542-9105-342e006b3915', 'value': 'H. Ric Harnsberger, MD'}], 'caseVersionId': '5ac20a6d-9ea8-4bc9-b512-1247aa2a745f', 'description': 'CPA-IAC facial nerve schwannoma extending to involve the labyrinthine segment of the facial nerve.\n\nAxial and coronal temporal bone CT images (#1-3) show enlargement of the labyrinthine segment of the facial nerve canal (open arrow). Axial T2 MR image (#4) shows both the IAC component (arrow) and the labyrinthine "tail" (open arrow). Enhanced MR images (#5-10) show an enhancing CPA (curved arrow, #5-8) and IAC (arrow, #5-7,9) and labyrinthine (open arrow, #5-6) components of facial nerve schwannoma. At first glance, the diagnosis of acoustic schwannoma might be suggested. However, the enhancing labyrinthine "tail" (open arrow, #10) in combination with the temporal bone CT findings confirm this lesion is a facial nerve schwannoma.', 'history': 'Patient with right sensorineural hearing loss. No history of facial nerve symptoms.', 'imagePoolId': '6671db4c-ab72-41e1-8a3e-16661f34f757', 'name': 'Subtle labyrinthine "tail"', 'teachingPoint': None, 'demographics': '68 Years old female'}, {'authors': [{'key': '6651ae1c-5f55-4d2e-9f68-46223037c90a', 'value': ' , '}], 'caseVersionId': '767afd14-f12f-4ede-82db-2b50d0e38f3d', 'description': 'Small facial nerve schwannoma of the lateral IAC, labrynthine segment and geniculate ganglion portions of CN7.\n\nAxial & coronal T-bone CT images (#1-2) show enlargement of the labyrinthine segment of the facial nerve (open arrow) and the geniculate fossa (curved arrow). \n\nHigh-resolution thin-section T2 images (#3-6) reveal an obvious tissue intensity mass in the fundal IAC (arrow) with subtle involvement of the geniculate ganglion area (curved arrow). Enhanced T1 MR images (#7-9) demonstrate the fundal IAC (arrow), labyrinthine segment (open arrow) and geniculate gangion (curved arrow) involvement as enhancing tumor in these locations.', 'history': None, 'imagePoolId': '1021d087-adeb-4a52-8882-db9cca0ab4e0', 'name': 'Small', 'teachingPoint': None}, {'authors': [{'key': '6651ae1c-5f55-4d2e-9f68-46223037c90a', 'value': ' , '}], 'caseVersionId': 'bffa4469-28c4-4088-aca2-35f950bb189b', 'description': 'Intracanalicular facial nerve schwannoma with characteristic labyrinthine "tail".\n\nAxial and coronal temporal bone CT images (#1-2) shows a normal appearing IAC with enlargement of the labyrinthine segment of the facial nerve canal (open arrow). On the coronal CT image the anterior tympanic segment of the facial nerve canal is normal (curved arrow). \n\nAxial enhanced T1 MR images (#3-5) reveal enhancing tumor in the IAC with a classic enhancing labyrinthine "tail" of the facial nerve schwannoma. The nonenhancing tympanic segment of the facial nerve is evident laterally (curved arrow).', 'history': 'Patient with 3 year history of mild right facial nerve paresis and moderate sensorineural hearing loss.', 'imagePoolId': '65d1433d-e5da-4a0e-9122-cb72ef8e168b', 'name': 'Classic labyrinthine "tail"', 'teachingPoint': None, 'demographics': '52 Years old female'}, {'authors': [{'key': '6651ae1c-5f55-4d2e-9f68-46223037c90a', 'value': ' , '}], 'caseVersionId': '005c61f5-8dc1-43c0-8c48-091f2b8e24a3', 'description': 'IAC facial nerve schwannoma with subtle labyrinthine segment and geniculate ganglion extension.\n\nAxial & coronal T1 C+ MR images show an avidly enhancing right IAC mass (arrow). Careful evaluation of the right geniculate ganglion area (open arrow) shows asymmetric enlargement and enhancement. Putting the two findings together allows the radiologist to come to the correct diagnosis of facial nerve schwannoma, not acoustic schwannoma. Normal left tympanic segment facial nerve enhancement (curved arrow, image #2).', 'history': 'Patient with right sensorineural hearing loss with normal facial nerve function.', 'imagePoolId': '3b051617-5d16-4b98-bab8-0c5e957a57fd', 'name': 'Subtle labyrinthine "tail"', 'teachingPoint': None, 'demographics': '75 Years old male'}], 'caseType': 'typical', 'name': 'TYPICAL'}
{'cases': [{'authors': [{'key': '564b28bd-4dbe-4066-9201-d10d689688fb', 'value': 'Christine M. Glastonbury, MBBS'}], 'caseVersionId': '179a054d-1bdc-4d4e-8e7d-ebeb9c8204fb', 'description': 'Variant case of a facial nerve schwannoma with a large cisternal component.\n\nAxial T1 WI MR (#1) shows a large right CPA mass (arrows) which is slightly hypointense to adjacent deformed cerebellum and pons. Axial thin-slice T2 WI (#2-4) shows the predominantly solid mass (arrow) to be hyperintense to brain parenchyma. A subtle rim of T2 hyperintense CSF is evident on some slices (curved arrow) delineating this as an extra-axial mass, which can also be seen to fill the right IAC (open arrow, #3). Post-contrast T1 C+ FS (#5-9) shows heterogeneous enhancement of the mass (arrow, #5-8) and no evidence of a dural attachment. Note that the mass fills the right IAC (curved arrow, #6,8) but a second component is found in the right middle cranial fossa (open arrow, #7-9). Perfusion MR (#10) with curve #2 indicating the mass (arrow) and showing very little return to baseline in keeping with this extra-axial tumor.\n\nPearls: While the most common CPA mass is a vestibular schwannoma, it is very important to follow the entire course of the mass into the IAC and in this case along the labyrinthine segment of the facial nerve to the geniculate ganglion, confirming that it arises from the facial nerve and not the vestibular nerve.', 'history': 'This patient was being screened for dementia and a posterior fossa mass was incidentally discovered. Facial nerve function is normal, but there is mild SNHL on direct testing.', 'imagePoolId': '7f14b2ee-ba6b-4c14-a945-b2491210e9a8', 'name': 'Large cisternal component', 'teachingPoint': None, 'demographics': '53 Years old female'}, {'authors': [{'key': '6651ae1c-5f55-4d2e-9f68-46223037c90a', 'value': ' , '}], 'caseVersionId': 'd17cd720-6840-4992-a021-6c72679512f9', 'description': 'Variant case of very small facial nerve schwannoma arising from the anterosuperior fundal IAC and extending along the labyrinthine segment of the facial nerve.\n\nAxial temporal bone CT (#1) shows subtle enlargement of the labyrinthine segment of the facial nerve canal (open arrow). \n\nHigh-resolution thin-section T2 MR images (#2-5) show the body of the schwannoma (arrow) nestled above the crista falciformis (black horizontal line) in the fundus of the IAC. Axial & coronal T1 C+ MR images (#5-8) reveal the expected enhancement of the body of the tumor (arrow) and the labyrinthine segment of the facial nerve extension (open arrow).', 'history': None, 'imagePoolId': '802b8f78-cbf9-4489-8db6-8037ec7b551e', 'name': 'Very small', 'teachingPoint': None}, {'authors': [{'key': '6651ae1c-5f55-4d2e-9f68-46223037c90a', 'value': ' , '}], 'caseVersionId': '7dcbb102-c355-45e2-b4b0-fdddd14ba6e9', 'description': 'Variant case of extensive facial nerve schwannoma that extends from the CPA cistern, through the IAC to involve the geniculate ganglion.\n\nInitial screening high-resolution thin-section T2 MR images (#1-3) show tissue intensity mass extending from the CPA through the IAC (arrow) with a large component present in the geniculate fossa (open arrow). Coronal image 3 reveals multiple intramural cysts within the geniculate ganglion component of the tumor (curved arrows).\n\nAxial & coronal enhanced T1 MR images (#4-8) demonstrate the IAC (arrow) and geniculate ganglion (open arrow) involvement again. On coronal image 8 a prominent intramural cyst (curved arrow) is readily visible. \n\nComment: All schwannomas, no matter where they are found, have a tendency to form intramural cysts, especially when they become large. This case is unusual in that the lesion is quite large. CPA-IAC facial nerve schwannoma tend to be diagnosed earlier in their natural history when they are smaller because of the early associated symptom, sensorineural hearing loss.', 'history': 'Patient with left sensorineural hearing loss.', 'imagePoolId': 'bfe4a316-709a-40ba-8222-382778587730', 'name': 'Large geniculate ganglion component', 'teachingPoint': None, 'demographics': '55 Years old female'}, {'authors': [{'key': '6651ae1c-5f55-4d2e-9f68-46223037c90a', 'value': ' , '}], 'caseVersionId': 'f0332a14-c716-4406-9b48-a56542bf8776', 'description': 'CPA-IAC facial nerve schwannoma with extension to geniculate ganglion and an associated large arachnoid cyst.\n\nAxial and coronal temporal bone CT images show an enlarged labyrinthine segment and geniculate fossa (open arrow) with erosion into the roof of the cochlea (arrow). These CT images signal the presence of a facial nerve schwannoma that has dehisced into the inner ear but they do not fully define the tumors full extent.\n\nAxial T2 (#7) and FLAIR (#8) images show a CPA-IAC tumor with a large associated arachnoid cyst (curved arrow). Both images show abnormal signal in the cochlear aspect of the membranous labyrinth (arrow). Enhanced axial & coronal T1 MR images (#9-14) show the extension of the tumor to involve the geniculate ganglion (open arrow, images 9 & 14) as well as the dehisced tumor inside the cochlea itself (arrow, image 10). \n\nComment: CPA arachnoid cyst, so called "herald cyst" is seen associated with acoustic schwannoma in < 1% of cases. This case is a rare CPA-IAC facial nerve schwannoma with an associated arachnoid cyst. It is possible to make the diagnosis of facial nerve schwannoma based on the labyrinthine facial nerve segment and geniculate ganglion involvement. The dehiscence into the cochlear membranous labyrinth complicates the radiologic appearance.', 'history': 'Patient with long history of progressive right facial nerve paralysis with recent development of profound right sensorineural hearing loss. ', 'imagePoolId': 'c85cef6f-2d98-4cdb-b5e2-1edc24828796', 'name': 'Large, with arachnoid cyst', 'teachingPoint': None, 'demographics': '56 Years old male'}, {'authors': [{'key': '624acd80-0502-4325-be71-e68fec740eb3', 'value': 'Richard H. Wiggins, III, MD, CIIP, FSIIM, FAHSE, FACR'}], 'caseVersionId': '7448f119-03e6-4d5b-8d2b-24f8f38d50a3', 'description': 'This is a rare variant case of facial nerve schwannoma found in the CPA cistern only without significant IAC or labyrinthine segment CNVII involvement.\n\nThe axial precontrasted T1 images (#1-2) show the lesion within the right CPA (arrow) as an extraaxial lesion with homogeneous signal intensity higher than CSF, and lower than adjacent cerebellar tissue.\n\nThe axial T2-weighted image (#3) show the heterogeneous T2 signal intensity of the lesion (arrow), and the axial FLAIR image (#4) shows signal intensity slightly higher than that of the adjacent cerebellar tissue. Both the T2 and FLAIR images show no significant abnormal signal intensity within the brain parenchyma.\n\nThe coronal T2-weighted images (#5-6) show the heterogeneous nature of this extraaxial lesion (arrow) with internal signal intensity similar to that of CSF.\n\nThe axial T1 postcontrasted images (#7-8) show the avid peripheral enhancement of the lesion (arrow) and the small bulbous portion of enhancing tissue extending into the right porous acusticus (open arrow).\n\nThe coronal T1 postcontrasted images (#9-10) confirm the avid peripheral enhancement of the mass (arrow) and the small bulbous portion extending into the opening of the internal auditory canal (IAC) (open arrow). There is no enhancement seen along the segments of the facial nerve within the temporal bone.', 'history': 'Patient presented with longstanding tinnitus and progressive hearing loss in the right ear. ', 'imagePoolId': '7e2f01f0-c80e-4873-86cf-c10df6b0d29a', 'name': 'CPA only', 'teachingPoint': 'At the time of surgery, the tumor was found to arise from the facial nerve in the CPA cistern.', 'demographics': '53 Years old male'}, {'authors': [{'key': '6651ae1c-5f55-4d2e-9f68-46223037c90a', 'value': ' , '}], 'caseVersionId': '7659adca-53a4-40af-b48b-a49da8a2cb2a', 'description': 'Variant case of facial nerve schwannoma with a large CPA component combined with a very thin labyrinthine segment isthmus and re-emergence of the tumor in the geniculate fossa.\n\nAxial temporal bone CT images (#1-2) show a normal proximal labyrinthine segment of the facial nerve canal (open arrow) with an obvious enlarged geniculate fossa (curved arrow). Flaring of the porus acusticus is evident.\n\nT1 C+ MR (#3-4) and enhanced SPGR (#4-6) axial images show a remarkably large CPA component of the tumor (arrow) as well as obvious IAC involvement. The labyrinthine segment of the facial nerve enhances but is not enlarged (open arrow). Tumor in the enlarged geniculate fossa is easily seen (curved arrow). \n\nComment: This case is considered variant both for the disproportionate size of the CPA component and the very thin isthmus of tumor between the fundal IAC tumor and the geniculate fossa component.', 'history': 'Patient with mild left facial palsy along with mild sensorineural hearing loss.', 'imagePoolId': 'e626bc08-ffc2-4096-9d2e-2f38c1706ae1', 'name': 'Large CPA component', 'teachingPoint': None, 'demographics': '40 Years old female'}], 'caseType': 'variant', 'name': 'VARIANT'}

Images

Selected Images

Axial graphic of a larger facial nerve schwannoma (FNS) shows cerebellopontine angle (CPA) ("ice cream") & internal auditory canal (IAC) ("cone") components that mimic a vestibular schwannoma. The labyrinthine segment of facial nerve involvement makes the diagnosis.

Axial T1 C+ FS MR in a patient with unilateral sensorineural hearing loss shows FNS with CPA & IAC components. Note the labyrinthine segment facial nerve tail , which differentiates FNS from vestibular schwannoma.

Axial T1 C+ FS MR shows enhancement of a large schwannoma expanding the geniculate fossa . The geniculate ganglion is the most common area involved. Correlating with smooth, bony expansile changes on CT is helpful to confirm diagnosis.

Axial T1 C+ FS MR shows an enhancing schwannoma involving the CPA-IAC & anterior genu of the facial nerve . This patient with NF2 has a large trigeminal schwannoma partly seen. A contralateral IAC schwannoma was also present (not shown).

Additional Images

Axial bone CT reveals smooth scalloped enlargement of the labyrinthine segment of the facial nerve canal and geniculate fossa in a patient with facial nerve schwannoma of CPA-IAC. Notice there is erosion into subjacent cochlea.

Axial T1WI C+ MR in the same patient shows facial nerve schwannoma with associated large arachnoid cyst . Notice the labyrinthine facial nerve schwannoma tail .

Axial C+ T1 FS MR in a patient with neurofibromatosis type 2 reveals bilateral enhancing vestibular schwannomas in the IACs. Careful inspection shows the left IAC has a smaller, anterior facial nerve schwannoma in addition. Notice also the left Meckel cave trigeminal schwannoma .

Magnified axial C+ FS T1 MR in a patient with neurofibromatosis type 2 demonstrates both an anterior facial nerve schwannoma and a posterior superior vestibular schwannoma in the left IAC fundus. Notice also the left Meckel cave trigeminal schwannoma .

Low-powered H&N micrograph shows the hypocellular appearance of spindled cells associated with a myxoid and edematous Antoni B area , adjacent to an Antoni A cellular area that is more hypercellular with a whorled pattern .

Axial T1 C+ FS MR in a patient with left facial nerve paralysis shows expansile enhancement of the tympanic segment of facial nerve , consistent with schwannoma.

Axial bone CT in the same patient shows localized expansion of the tympanic segment of facial nerve due to schwannoma , where tumor appears to erode the short process of incus. Tympanic segment schwannomas more often cause facial nerve paralysis &/or conductive hearing loss.

39 KiB Raw Permalink Blame History

KEY FACTS

Terminology

Imaging

Top Differential Diagnoses

Pathology

Clinical Issues

TERMINOLOGY

Abbreviations

Synonyms

Definitions

IMAGING

General Features

Best diagnostic clue

Location

Size

Morphology

CT Findings

Bone CT

MR Findings

T1WI C+

Imaging Recommendations

Best imaging tool

DIFFERENTIAL DIAGNOSIS

PATHOLOGY

General Features

Etiology

Genetics

Associated abnormalities

Gross Pathologic & Surgical Features

Microscopic Features

CLINICAL ISSUES

Presentation

Most common signs/symptoms

Demographics

Age

Epidemiology

Natural History & Prognosis

Treatment

DIAGNOSTIC CHECKLIST

Consider

Image Interpretation Pearls

References

Selected References

Cases

Images

Selected Images

Additional Images

39 KiB

Raw Permalink Blame History