Cranial nerve denervation, what signs to recognise and common pitfalls.

Size: px

Start display at page:

Download "Cranial nerve denervation, what signs to recognise and common pitfalls."

Roy May
5 years ago
Views:

1 Cranial nerve denervation, what signs to recognise and common pitfalls. Poster No.: C-1238 Congress: ECR 2014 Type: Educational Exhibit Authors: C. Martins Jarnalo, G. Lycklama à Nijeholt, F. Barkhof ; Amsterdam/NL, Den Haag/NL Keywords: Inflammation, Infection, Cancer, Diagnostic procedure, MR, CT, Neuroradiology peripheral nerve, Head and neck, Ear / Nose / Throat DOI: /ecr2014/C-1238 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 56

2 Learning objectives To give insight into the different stages of denervation and it's associated MR-imaging features. To provide a pattern of recognition for denervation of the cranial nerves and associated pitfalls. To give an overview of the anatomical pathways of the cranial nerves. Background Different disease entities can give denervation of cranial nerves. Because of the long tract that some nerves follow, the actual lesion or pathology causing the denervation can be difficult to recognise. Furthermore, the first stages of denervation can mimic other pathologies. Knowledge of the pattern of denervation of cranial nerves is therefore needed to recognise this entity and prevent making a misdiagnosis. Findings and procedure details Muscle denervation and associated MR findings: There are four stages of muscle denervation: -Acute stage (1 week) No abnormalities -Early subacute (2-4 weeks) T2 hyperintensity and muscle edema. After contrast administration enhancement can occur. This stage is especially prone to misdiagnosis of a tumor. -Late subacute (1-12 months) Gradual fatty replacement, intermixed with oedema and contrast enhancement. Page 2 of 56

This stage can give a birarre appearance and recognition is important to detect this entity -Chronic phase (> 12 months) Progressive fatty replacement, no enhancement The fat van give a voluminous

3 This stage can give a birarre appearance and recognition is important to detect this entity -Chronic phase (> 12 months) Progressive fatty replacement, no enhancement The fat van give a voluminous look to the muscle. You could overlook this stage if you don't include a T1-non fat sat serie. CASES Case I A female, 40 year old patient presented with a week history of doublevision. Neurologic examination revealed a downward lateral gaze, midriasis and ptosis of the left eye. Fig. 37: Axial (left) and coronal (middle) T1 post gadolinium and axial CISS(right). Images reveal a posterior communicating artery (pcom)aneurysm. On the CISS we see a lateral gaze of the left eye. References: Medisch Centrum Haaglanden, The Hague/NL Conclusion: Left pcom aneurysm causing an oculomotor palsy. Page 3 of 56

There where no signs of subarachnoid bleeding on CT on CSF analysis. rd Review anatomy of the 3 cranial nerve Fig. 39: Sagittal oblique illustration of the cranial nerves exiting the brainstem.

The nerve then exits the brainstem in a horizontal tract and passes between the posterior cerebellar artery and the superior cerebellar artery (SCA) and also near the pcom.

4 There where no signs of subarachnoid bleeding on CT on CSF analysis. rd Review anatomy of the 3 cranial nerve Fig. 39: Sagittal oblique illustration of the cranial nerves exiting the brainstem. References: "The cranial nerves" Leblanc The oculomotor nerve receives neuronal fibers from the oculomotor nucleus and Edinger Westphal nucleus, both situated medially in the mesencephalon. The nerve then exits the brainstem in a horizontal tract and passes between the posterior cerebellar artery and the superior cerebellar artery (SCA) and also near the pcom. More rostrally it traverses the cavernous sinus. It enters the orbit through the superior orbital fissure. Fig. 40: Oculomotor nerve traversing the ambiens cistern. References: VU Medical Center - Amsterdam/NL and Netter Page 4 of 56

right facial pain, consistent with trigeminal neuralgia. Fig.

5 Fig. 38: The oculomotor nerve innervates all of these muscles. References: Sesam Pocket atlas of sectional Anatomy Case II A 50 year old male presented with a subacute onset of right facial pain, consistent with trigeminal neuralgia. Fig. 32: Axial Ciss and T1 post gadolinium There is a lesion in the right pre-pontine cistern at the trigeminal nerve, growing into Meckels cave. The lesion is partly cystic and enhances at the solid portions. Page 5 of 56

6 References: Medisch Centrum Haaglanden, The Hague/NL Page 6 of 56

7 Fig. 33: Axial T2 and T1 post gadolinium The masticator muscles show no abnormalities References: Medisch Centrum Haaglanden, The Hague/NL A partial resection was planned and the patient went into follow up. A gradual denervation was observed: Page 7 of 56

8 Page 8 of 56

9 Fig. 34: Axial T2 and T1 post gadolinium Voluminous aspect of the masseter muscle with vivid enhancenment: Early subacute stage. References: Medisch Centrum Haaglanden, The Hague/NL Page 9 of 56

10 Page 10 of 56

11 Fig. 35: Axial T2 and T1 post gadolinium The masseter muscle is less voluminous and there is gradual fatty replacement. Focal pachy enhancement: Late subacute fase. References: Medisch Centrum Haaglanden, The Hague/NL Page 11 of 56

12 Page 12 of 56

Fig. 36: Axial T2 and T1 post gadolinium After one year the masseter muscle has become more atrofic. There is still slight enhancement, so it is not yet fully in the chronic stage.

13 Fig. 36: Axial T2 and T1 post gadolinium After one year the masseter muscle has become more atrofic. There is still slight enhancement, so it is not yet fully in the chronic stage. References: Medisch Centrum Haaglanden, The Hague/NL Conclusion: Trigeminal schwannoma with observed gradual denervation of the masticator muscles. th Review anatomy 5 cranial nerve: The trigeminal nerve is the largest cranial nerve. The sensory nucleus extends from the mesencephalon through the pons to the medulla oblongata. The smaller motor nucleus is situated in the pons, just ventral to the sensory nucleus Fig. 24: Illustration scheme of the trigeminal nerve the sensory innervation of the three branches is illustrated. The sensory nucleus extends from the mesencephalon through the pons to the medulla oblongata. The smaller motor nucleus is situated in the pons. References: C.O. Martins Jarnalo Page 13 of 56

14 Page 14 of 56

Fig. 23: Axial Ciss The trigeminal nerve is shown on both sides as a thick nerve coursing straight though the pre-pontine cistern, to enter Meckel's cave.

15 Fig. 23: Axial Ciss The trigeminal nerve is shown on both sides as a thick nerve coursing straight though the pre-pontine cistern, to enter Meckel's cave. References: VU Medical Center - Amsterdam/NL The nerve courses through the pre-pontine cistern and enters Meckels cave where its Gasserian ganglion is situated. Fig. 25: Coronal T1 post gadolinium References: VU Medical Center - Amsterdam/NL Page 15 of 56

16 Fig. 26: Coronal T1 post gadolinium Case of neuroborreliosis with leptomeningeal disease, situated at the right pre-pontine portion of the trigeminal nerve. Enhancement of the nerve is pointed out with the red arrow. References: VU Medical Center - Amsterdam/NL Page 16 of 56

Fig. 27: Axial CT of the skull base. Bone window Red arrow: foramen ovale Yellow arrow: foramen spinosum Blue arrow: Vertical portion of carotid artery.

17 Fig. 27: Axial CT of the skull base. Bone window Red arrow: foramen ovale Yellow arrow: foramen spinosum Blue arrow: Vertical portion of carotid artery. References: Medisch Centrum Haaglanden, The Hague/NL The first branch (ophtalmic) and the second branch (mandibular) course through the cavernous sinus. The first then courses through the superior orbital fissure; the second through the foramen rotundum. Page 17 of 56

Fig. 28: Coronal and axial T1 post gadolinium Tumor invasion in the left mandibular branch of the trigeminal nerve, the red arrow depicts the foramen rotundum.

18 Fig. 28: Coronal and axial T1 post gadolinium Tumor invasion in the left mandibular branch of the trigeminal nerve, the red arrow depicts the foramen rotundum. References: VU Medical Center - Amsterdam/NL The motor part of the nerve follows the course of the second branch and innervates the masticator muscles: masseter; temporalis and the lateral and medial pterygoid muscles. Potential pitfalls: -to image the entire course of this complex nerve, high resolution imaging with thin slices and possibly multi modality ( MR and CT) is required, in order not to miss the pathology. -the first stages can mimic inflammation or infection. Case III A female patient of 30 years with an unremarkable history, presented with doublevision because of the unability to abduct the right eye. An abducens nerve palsy was suspected. MR: Page 18 of 56

19 Fig. 7: Axial 3D T1 post gadolinium An extra-axial lesion is noted at the left sphenoid ridge which grows into the left cavernous sinus. Notice also the convergent eyes because the left eye is not able to abduct. References: Medisch Centrum Haaglanden, The Hague/NL There where no abnormalities noted of the lateral rectus muscle. It enhanced normaly as the other eye muscles. Page 19 of 56

20 Conclusion: Acute left abducent nerve palsy due to a meningeoma growing into the cavernous sinus. th Review anatomy 6 cranial nerve: Fig. 8: Scheme of the abducens nerve Arrow pointing out the abducens nerve References: Netter The nucleus of the abducens nerve can be found in the lower posterior aspect of the pons, adjacent to the fourth ventricle. Fibers of the ipsilateral facial nerve pass behind this nucleus. The abducens nerve then leaves te brainstem between the pons and the medulla oblongata. Page 20 of 56

21 Fig. 12: Axial DWI (B1000) Another case of left abducens paresis, this time due to a small infarction at the site of the nucleus. References: VU Medical Center - Amsterdam/NL Page 21 of 56

22 Fig. 9: Abducens nerve leaving the brainstem References: Netter Page 22 of 56

References: VU Medical Center - Amsterdam/NL The nerve then ascends

23 Fig. 10: Reformatted Ciss showing the ascending abducens nerve in the pre-pontine cistern. References: VU Medical Center - Amsterdam/NL The nerve then ascends in te pre-pontine cistern for a short length and then ascends further in dorello's canal along the clivus. Page 23 of 56

24 Fig. 11: Axial CiSS Red arrow pointing out Dorello's canal. This is not always visible. References: VU Medical Center - Amsterdam/NL The nerve then courses through the caverneous sinus, it is the nerve which runs closest to the carotid artery. Fig. 13: Illustration coronal orientation of the cavernous sinus. Blue arrow pointing out the abducens nerve, close to the carotid artery References: A. Micheau MD Page 24 of 56

25 Fig. 14: Axial T1 post gadolinium right abducens nerve palsy due to a Kahler manifestation, growing into the cavernous sinus. References: VU Medical Center - Amsterdam/NL The nerve then leaves the cavernous sinus coursing into the orbit through the superior orbital fissure. At last it innervates the lateral rectus muscle. Potential pitfalls: - long tract, scrutinise every anatomic site Case IV Male patient, known with neurofibromatosis II with a history of a facial nerve schwannoma and peripheral palsy. MR: Page 25 of 56

26 Fig. 41: Axial CISS (left) and T1 post gadolinium (right). Enhancing mass in the left internal acoustic meatus. References: VU Medical Center - Amsterdam/NL Page 26 of 56

27 Page 27 of 56

28 Fig. 42: Coronal T1 fat sat post gadolinium (upper), axial Ciss (lower). Left sided atrohy of the facial muscles. References: VU Medical Center - Amsterdam/NL th Review anatomy of the 7 nerve: The facial nerve exits the brainstem in a lateral position in the lower pons. It crosses the cerebello pontine cistern to enter the internal acoustic meatus. In the petrosal bone it forms the geniculate ganglion (knee) which makes a sharp angle. It courses further dorsally and caudally to eventually exit the skullbase through the stylomastoid foramen. Further on it courses the parotid gland where it branches off in 5 different divisions. Page 28 of 56

29 Page 29 of 56

Fig. 44: Axial Ciss. Facial nerve in the cerebello pontine cistern. References: VU Medical Center - Amsterdam/NL Fig. 43: Axial (left) and coronal (right) T1 post gadolinium.

30 Fig. 44: Axial Ciss. Facial nerve in the cerebello pontine cistern. References: VU Medical Center - Amsterdam/NL Fig. 43: Axial (left) and coronal (right) T1 post gadolinium. Patient with facial neuritis and extensive enhancement of the facial nerve. On the left the geniculate ganglion is pointed out. On the right we see the descending part of the facial nerve in the petrosal bone. References: VU Medical Center - Amsterdam/NL A female patient with a history of Neurofibromatosis type I and a vocal cord paralysis on the right side, presented with hypercapnia. Laryngoscopy shows a bilateral vocal cord paralysis and a tracheostomy was immediately placed. A CT of the thorax and a MR of the brain and head and neck is performed to localise the culprit lesion. The CT of the thorax showed no abnormalities. MR: Page 30 of 56

Fig. 1: Axial T2-STIR The left vocal cord is displaced to the midline, just as the right vocal cord (history of right vocal cord paralysis) Also note the

31 Fig. 1: Axial T2-STIR The left vocal cord is displaced to the midline, just as the right vocal cord (history of right vocal cord paralysis) Also note the high signal intensity of the left vocal cord compatible with denervation in the early subacute stage. References: VU Medical Center - Amsterdam/NL Page 31 of 56

32 Fig. 3: Axial T1 post gadolinium There is slight enhancement of the left vocal cord References: VU Medical Center - Amsterdam/NL Page 32 of 56

33 Fig. 2: Axial T2 A new lesion is noticed in the posterior left part of the medulla oblongata. References: VU Medical Center - Amsterdam/NL The lesion did not enhance after contrast administration (image not shown) Conclusion: Denervation of the left vocal cord in the early subacute stage, due to a non-enhancing lesion in the posterior part of the left medulla oblongata, in a patient with known Neufofibromatosis Type I Page 33 of 56

34 Differential: Hamartoma or low grade astrocytoma. th Review anatomy 10 cranial nerve: Fig. 4: Illustration scheme of the vagus nerve References: Netter Three nucleii provide the tenth cranial nerve: - Ambiguus nucleus - Dorsal nucleus - Solitary nucleus These are located in the posterior part of the medulla oblongata The vagus nerve exits the brainstem just posterior to the olive. Page 34 of 56

35 Fig. 5: Axial CISS Arrow showing the vagus nerve in the basal cisterns leaving the brainstem References: VU Medical Center - Amsterdam/NL The vagus nerve then leaves the skull base through the pars vascularis of the jugular foramen. Page 35 of 56

Fig. 6: Axial CT, bone window. References: VU Medical Center - Amsterdam/NL The laryngeus recurrens nerve is a branch which innervates the muscles of the larynx (except the cricothyroid muscle).

36 Fig. 6: Axial CT, bone window. References: VU Medical Center - Amsterdam/NL The laryngeus recurrens nerve is a branch which innervates the muscles of the larynx (except the cricothyroid muscle). This branch first passes under the right subclavian artery on the right side and under the aortic arch on the left side, before ascending to the larynx (hence the name recurrent nerve) It is therefore important to look for pathology in the upper thorax too, especially with a left vocal cord palsy. Potential pitfalls: - glottis carcinoma - include a Chest CT Case V A male patient of 47 years, presented with left shoulder pain. He also noticed tingling sensations in the whole arm when he streched it. Neurologic examination revealed a scapula alata and possible atrofy of the deltoid muscle. The clinician thought of a lesion of the thoracicus longus nerve and ordered an MR of the head and neck. Page 36 of 56

37 Fig. 29: Axial T2 Fat Saturated There is less volume of the left trapezius muscle, compared to the right. References: Medisch Centrum Haaglanden, The Hague/NL Page 37 of 56

38 Fig. 30: Axial T1 The left trapezius muscle also shows areas of fatty replacement. References: Medisch Centrum Haaglanden, The Hague/NL Page 38 of 56

Fig. 31: Coronal T2 TIRM There is a slightly higher signal intensitiy of the sternocleidomastoid muscle and the trapezius muscle indicating edema.

39 Fig. 31: Coronal T2 TIRM There is a slightly higher signal intensitiy of the sternocleidomastoid muscle and the trapezius muscle indicating edema. References: Medisch Centrum Haaglanden, The Hague/NL Imaging of the course of the left accesory nerve revealed no pathologic lesions. Conclusion: Late subacute accessory nerve denervation due to a neuritis. th Review anatomy 11 cranial nerve: Page 39 of 56

40 Fig. 22: Illustration scheme of the 11th cranial nerve References: C.O. Martins Jarnalo It is debated whether the accessory nerve is a true cranial nerve, because parts of the nuclei originate in the cervical spinal cord. The nerve ascends throught the foramen magnum where it joins the vagus nerve to course through the pars vascularis of the jugular foramen. It then courses posteriorly to innervate the sternocleidomastoid and trapezius muscle. Potential pitfalls: -This entity can be difficult to asses clinically. Pathology is sometimes searched by the clinician at the cervical spine or shoulder, as in our case. We should be alert to recognise this entity and also image the accessory nerve. Case VI Page 40 of 56

41 A 52 year old female presented with a two year history of hemiatrophy of the right hemitongue. When sticking her tongue out, it points to the right. A twefth nerve palsy was suspected. MR: Page 41 of 56

42 Page 42 of 56

43 Fig. 15: Coronal T1 The right hemitongue shows atrophy and extensive fatty replacement, without disturbance of the intrinsic tongue anatomy. References: VU Medical Center - Amsterdam/NL Page 43 of 56

44 Page 44 of 56

45 Fig. 16: Coronal T1 fatsat post gadolinium The right hemitongue shown no enhancement References: VU Medical Center - Amsterdam/NL Fig. 17: Axial T2 There is a lesion at the right petro-occipital fissure with a mixed signal intensity on T2, but predominantly high it has lobulated margins References: VU Medical Center - Amsterdam/NL Page 45 of 56

46 Fig. 18: Axial T2 The lesion extends caudally, into the hypoglossal canal References: VU Medical Center - Amsterdam/NL Page 46 of 56

47 Fig. 19: Axial T1 post gadolinium. The lesion shows heterogeneous contrast enhancement. References: VU Medical Center - Amsterdam/NL Conclusion: Chonic atrophy of the right hemitongue due to a skull base lesion growing into the hypoglossal canal, which turned out to be a chondrosarcoma. th Review anatomy 12 cranial nerve: Page 47 of 56

Fig. 20: Illustration, scheme of the twelfth cranial nerve References: Netter The hypoglossal nucleus is situated in the posterior medulla oblongata.

48 Fig. 20: Illustration, scheme of the twelfth cranial nerve References: Netter The hypoglossal nucleus is situated in the posterior medulla oblongata. After a short course through the basal cisterns is courses through its own skullbase foramen: the hypoglossal canal. Branches of C1 C2 and C3 then join the nerve to innervate the right hemitongue, including the extrinsic tongue musculature. Page 48 of 56

49 Fig. 21: Axial T1 post gadolinium Case of a metastasis in the right hypoglossal canal. References: VU Medical Center - Amsterdam/NL Potential pitfalls: - especially in the early stages: malignant mass or vascular malformation Imaging of the course of the left accesory nerve revealed no pathologic lesions. Conclusion: Page 49 of 56

50 Late subacute accessory nerve denervation due to a neuritis. QUIZ The answers will be shown in the conclusion part. Question 1: Which branch of the trigeminal nerve contains the motor part? Question 2: Through which foramen does the facial nerve exit the skull? Question 3: Why is the accessory nerve not considered to be a true cranial nerve? Question 4: Which stage of denervation is especially prone to misdiagnosis of a tumor? Images for this section: Page 50 of 56

51 Page 51 of 56

52 Fig. 45: Table of cranial nerve muscle innervation. Page 52 of 56

53 Conclusion Stages of muscle denervation: Acute stage (1 week) No abnormalities Early subacute (2-4 weeks) Muscle edema. Enhancement can occur. Late subacute (1-12 months) Fatty replacement, intermixed with oedema and enhancement. Chronic phase (> 12 months) Progressive fatty replacement, no enhancement Potential pitfalls: Early subacute fase: mistaken for a tumor Late subacute fase: mistaken for inflammation/infection Abducens (6 ) and trigeminal (5 ) nerve: long complex tract. Include high resolution and images, also multimodality imaging. Accesory (11 ) Actively search for trapezius and scm-muscle abnormalities. Clinicians do not always recognise this entity. th Recurrence (10 ) nerve palsy: include a chest CT th th th Page 53 of 56

54 Page 54 of 56

55 Fig. 45: Table of cranial nerve muscle innervation. References: C.O. Martins Jarnalo Answers to the Quiz: Question 1: The second/ mandibular branch. Question 2: The stylomastoid foramen. Question 3: Most of the accesory nerve has its origin in the cervical spinal cord. Question 4: The early subacute stage ( 1-3 weeks) due to swelling. Cranial nerve denervation can be difficult to recognise and can easily be mistaken for other diseases. We provide an overview of the findings of nerve denervation, multiple cases of cranial nerves and a final quiz. Personal information C.O. Martins Jarnalo, M.D. Department of Radiology, Medisch Centrum Haaglanden, The Hague, the Netherlands and VU- Medisch Centrum, Amsterdam, the Netherlands. G.J Lycklama à Nijeholt, M.D. Ph.D. Department of Radiology, Medisch Centrum Haaglanden, The Hague, the Netherlands Prof. F. Barkhof, M.D. Ph.D. VU- Medisch Centrum, Amsterdam, the Netherlands References - Diagnostic Imaging Head and neck , Amirsys, Inc. - "The brainstem, anatomy, Assesment and Clinical syndromes" Hurley, Hayman et al. 2010, Journal of Neuropsychiatry and clinical Neuroscience - "Clinical Neuroradiolofy" Hathout Page 55 of 56

56 - "The Cranial Nerves: Anatomy - Imaging - Vascularisation" Leblanc Page 56 of 56

Patterns of perineural spread of head and neck malignancies.

Patterns of perineural spread of head and neck malignancies. Poster No.: C-1234 Congress: ECR 2014 Type: Educational Exhibit Authors: C. Martins Jarnalo, G. Lycklama à Nijeholt, E. Sanchez-Aliaga, 1 1