Acoustic neuroma CT: Difference between revisions

Jump to navigation Jump to search
No edit summary
No edit summary
 
(23 intermediate revisions by 5 users not shown)
Line 3: Line 3:
{{CMG}}{{AE}}{{Simrat}}
{{CMG}}{{AE}}{{Simrat}}
==Overview==
==Overview==
Head CT scan may be diagnostic of Acoustic neuroma. Findings on CT scan diagnostic of acoustic neuroma include erosion and widening of the internal acoustic canal.
[[CT scan]] of the [[head]] may be [[Diagnosis|diagnostic]] of acoustic neuroma. Findings on [[Computed tomography|CT scan]] diagnostic of acoustic neuroma include erosion and widening of the [[Internal auditory meatus|internal acoustic canal]].
==CT==
==CT==
CT scans with bone windows can also be of prognostic significance as the extent of widening of the IAC and the extent of tumor growth anterior and caudal to the IAC are predictive of postoperative hearing loss.If MRI cannot be done on patient, high resolution CT scanning with and without contrast is an alternative.On MRI and CT scans, Vestibular schwannoma can be seen as enhancing lesions in the region of the internal auditory canal with variable extension into the cerebellopontine angle. CT scans with bone windows can also be of prognostic significance. CT may show erosion and widening of the internal acoustic canal. The density of these tumours on non-contrast imaging is variable, and often they are hard to see, especially on account of beam hardening and streak artifact form the adjacent petrous temporal bone. Contrast enhancement is present, but can be underwhelming, especially in larger lesions with cystic components.<ref>{{Cite web | title =Radiopedia CT findings| url =http://radiopaedia.org/articles/acoustic-schwannoma }}</ref>
*[[Computed tomography|CT scan]] with [[bone]] windows can be of [[prognostic]] significance as the extent of widening of the [[internal auditory meatus]] and the extent of [[tumor]] growth [[Anatomical terms of location|anterior]] and [[caudal]] to the [[internal auditory meatus]] are predictive of postoperative [[hearing loss]].
Well-performed scanning can demonstrate tumors 1-2 mm in diameter. However, even with intravenous contrast enhancement thin-cut CT scanning can miss tumors as large as 1.5 cm even. Fine-cut CT scanning of the internal auditory canal with contrast can detect medium-size or large tumor but are not reliable imaging techniques to detect a tumor smaller than 1-1.5 cm.
*On [[Computed tomography|CT scan]], vestibular [[schwannoma]] can be seen as an enhancing [[lesions|lesion]] in the region of the [[Internal auditory meatus|internal auditory canal]] with variable extension into the [[cerebellopontine]] angle.<ref>{{Cite journal
 
| author = [[C. Matthies]], [[M. Samii]] & [[S. Krebs]]
[[Image:CT acoustic neuroma.jpg|CT Acoustic Neuroma]]<ref>Image courtesy of Dr. Frank Gaillard  [http://www.radiopaedia.org Radiopaedia] (original file [http://radiopaedia.org/cases/intracanalicular-acoustic-schwannoma]).[http://radiopaedia.org/licence Creative Commons BY-SA-NC</ref>
| title = Management of vestibular schwannomas (acoustic neuromas): radiological features in 202 cases--their value for diagnosis and their predictive importance
| journal = [[Neurosurgery]]
| volume = 40
| issue = 3
| pages = 469–481
| year = 1997
| month = March
| pmid = 9055285
}}</ref>
*[[Computed tomography|CT]] may show erosion and widening of the [[Internal auditory meatus|internal acoustic canal]].  
*[[Contrast]] enhancement is present, but can be underwhelming, especially in larger [[lesions]] with [[Cyst|cystic]] components.
*Well-performed scanning can demonstrate [[Tumor|tumors]] 1 - 2 mm in [[diameter]]. However, even with [[intravenous]] contrast enhancement, thin-cut [[Computed tomography|CT]] scanning can miss [[Tumor|tumors]] as large as 1.5 cm.  
*Fine-cut [[Computed tomography|CT]] scanning of the [[Internal auditory meatus|internal auditory canal]] with [[contrast]] can detect medium-size or large [[tumor|tumors]] but are not reliable [[imaging]] techniques to detect a [[tumor|tumors]] smaller than 1 - 1.5 cm.
[[File:Acoustic.neuroma.ct.1.jpg|thumb|none|200px|[[Computed tomography|CT]] image of a patient with acoustic neuroma]] <ref>Image courtesy of Dr Frank Gaillard. [http://www.radiopaedia.org Radiopaedia] (original file [http://radiopaedia.org/cases/acoustic-schwannoma-2]).[http://radiopaedia.org/licence Creative Commons BY-SA-NC</ref>
[[File: CT of neurofibromatosis type 2.jpg|thumb|none|200px|[[Computed tomography|CT]] image of [[Neurofibromatosis type II|neurofibromatosis type 2]]]]
<ref>Image courtesy of Dr Prashant Mudgal. [http://www.radiopaedia.org Radiopaedia] (original file [http://radiopaedia.org/cases/neurofibromatosis-type-ii-2]).[http://radiopaedia.org/licence Creative Commons BY-SA-NC</ref>


==References==
==References==
Line 15: Line 30:
{{WH}}
{{WH}}
{{WS}}
{{WS}}
[[Category:Types of cancer]]
[[Category:Disease]]
[[Category:Up-To-Date]]
[[Category:Oncology]]
[[Category:Medicine]]
[[Category:Otolaryngology]]
[[Category:Neurology]]
[[Category:Neurosurgery]]

Latest revision as of 18:30, 26 April 2019

Acoustic neuroma Microchapters

Home

Patient Information

Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Acoustic neuroma from other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications and Prognosis

Diagnosis

Diagnostic Study of Choice

History and Symptoms

Physical Examination

Laboratory Findings

Electrocardiogram

X-ray

Echocardiography or Ultrasound

CT

MRI

Other Imaging Findings

Other Diagnostic Studies

Treatment

Medical Therapy

Surgery

Primary Prevention

Secondary Prevention

Cost-Effectiveness of Therapy

Future or Investigational Therapies

Case Studies

Case #1

Acoustic neuroma CT On the Web

Most recent articles

cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Acoustic neuroma CT

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Acoustic neuroma CT

CDC on Acoustic neuroma CT

Acoustic neuroma CT in the news

Blogs on Acoustic neuroma CT

Directions to Hospitals Treating Acoustic neuroma

Risk calculators and risk factors for Acoustic neuroma CT

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [3]Associate Editor(s)-in-Chief: Simrat Sarai, M.D. [4]

Overview

CT scan of the head may be diagnostic of acoustic neuroma. Findings on CT scan diagnostic of acoustic neuroma include erosion and widening of the internal acoustic canal.

CT

CT image of a patient with acoustic neuroma

[2]

CT image of neurofibromatosis type 2

[3]

References

  1. C. Matthies, M. Samii & S. Krebs (1997). "Management of vestibular schwannomas (acoustic neuromas): radiological features in 202 cases--their value for diagnosis and their predictive importance". Neurosurgery. 40 (3): 469–481. PMID 9055285. Unknown parameter |month= ignored (help)
  2. Image courtesy of Dr Frank Gaillard. Radiopaedia (original file [1]).[http://radiopaedia.org/licence Creative Commons BY-SA-NC
  3. Image courtesy of Dr Prashant Mudgal. Radiopaedia (original file [2]).[http://radiopaedia.org/licence Creative Commons BY-SA-NC

Template:WH Template:WS