History

Fact Explanation
Introduction Twelfth cranial nerve is purely motor cranial nerve which supply the four pairs of tongue muscles. Nuclei for the twelfth cranial nerve situated in lower medulla oblongata posterior to the medial lemniscus either side of the midline. Tongue has four pairs of extrinsic muscles and four pairs of intrinsic muscles. The extrinsic muscles originate from bone and extend to the tongue whereas four paired intrinsic muscles of the tongue originate and insert within the tongue. Interestingly nerve fibres to the genioglossus has only contralateral cortical representation whereas the other three pairs of extrinsic muscles have bilateral cortical representation. Action of genioglossus is protrusion of the tongue. So when there is unilateral cortical or upper tract lesion only the opposite side genioglossus affect and tongue deviate to the side away from the cortical lesion. Lower motor nerve type involvement can affect all the ipsilateral muscles and leads to tongue deviation to the same side of the lesion. So upper motor type lesion may involve associated hemiplegia of the contralateral side. Usually there is spastic pointing tongue is seen in upper motor involvement whereas flaccid tongue and fasciculations are seen in lower motor type lesion. Bilateral upper motor lesions, seen in pseudobulbar palsy, produce moderate to severe inability of the tongue to function[3,4].
Slurred speech(dysarthria) Unilateral or bilateral paralysis results in difficult in pronunciation [1].
Difficulty in swallowing(dysphagia) Unilateral or bilateral paralysis impair swallowing [2].
Difficult potrusion of tongue Tongue deviates towards the affected side of the hypoglossal nerve damage [2].
Snoring at sleep Paralysis of the tongue fall back on pharynx on supine position may cause upper airway obstruction [1].
References
  1. LORO WA, OWENS B. Unilateral Hypoglossal Nerve Injury in a Collegiate Wrestler: A Case Report J Athl Train [online] 2009, 44(5):534-537 [viewed 25 September 2014] Available from: doi:10.4085/1062-6050-44.5.534
  2. HO MW, FARDY MJ, CREAN SJ. Persistent idiopathic unilateral isolated hypoglossal nerve palsy: a case report. Br Dent J [online] 2004 Feb 28, 196(4):205-7 [viewed 25 September 2014] Available from: doi:10.1038/sj.bdj.4810980
  3. UMAPATHI T, VENKETASUBRAMANIAN N, LECK KJ, TAN CB, LEE WL, TJIA H. Tongue deviation in acute ischaemic stroke: a study of supranuclear twelfth cranial nerve palsy in 300 stroke patients. Cerebrovasc Dis [online] 2000 Nov-Dec, 10(6):462-5 [viewed 26 September 2014] Available from: doi:16108
  4. NILSSON SF, PETERSON PA. Studies on thyroid hormone-binding proteins. I. The subunit structure of human thyroxine-binding globulin and its interaction with ligands. J Biol Chem [online] 1975 Nov 10, 250(21):8543-53 [viewed 26 September 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/388

Examination

Fact Explanation
Atrophy of the affected half of tongue Denervation of the tongue muscle leads to wasting of muscle [1,3].
Protrusion of tongue towards the affected side When protruding tongue out force from the intact genioglossus muscle pull tongue out deviating the tip of tongue towards the paralysed side [1,3].
Fasciculations of the tongue of the affected side Intrinsic involuntary muscle twitching of the affected muscle usually associated with lower motor nerve damage of hypoglossal nerve or its nucleus [1-3].
Small pointed stiff tongue This is associated with upper motor neurone lesion of the hypoglossal nerve [1,2].
References
  1. KINOSHITA Y, TSUURA M, TERADA T, NAKAI K, ITAKURA T, TERASHITA T. Medial medullary syndrome with contralateral face hypalgesia: a report of two cases. J Stroke Cerebrovasc Dis [online] 1998 Jan-Feb, 7(1):96-9 [viewed 25 September 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/17895062
  2. AHMED SV, AKRAM MS. Isolated unilateral idiopathic transient hypoglossal nerve palsy. BMJ Case Rep [online] 2014 Jun 26 [viewed 25 September 2014] Available from: doi:10.1136/bcr-2014-203930
  3. SAYAN A, ABEYSINGHE AH, BRENNAN PA, ILANKOVAN V. Persistent idiopathic unilateral hypoglassal nerve palsy: a case report. Br J Oral Maxillofac Surg [online] 2014 Jul, 52(6):572-4 [viewed 25 September 2014] Available from: doi:10.1016/j.bjoms.2014.04.005

Differential Diagnoses

Fact Explanation
Ischaemic Stroke Brain stem stroke by thrombus affecting hypoglossal nerve nucleus leads to lower motor type deformity and cortex and internal capsular lesions lead to upper motor type deformity [1,3].
Base of skull fractures Traumatic injuries may damage hypoglossal nerve when leaving from medulla oblongata through the hypoglossal canal [1,3].
Base of skull tumours Expanding lesion may compress or involve the hypoglossal nerve or its nucleus [1,5].
Motor neurone disease( Amyotrophic lateral sclerosis) Involve motor cranial nerve and their nuclei, leading to bilateral lower motor type hypoglossal nerve palsy [1,4].
Haemorrhagic stroke Brain stem haemorrhage may compress and involve the hypoglossal nerve nucleus and other adjacent nerve nuclei [1,4].
Medial medullary syndrome Thrombus blocking vertebral artery impairs the blood supply of the medial medulla affecting hypoglossal nerve as well as descending corticospinal tract giving rise to lower motor hypoglossal nerve palsy [1,4].
Brain abscess Abscess may involve brain stem and affect the hypoglossal nucleus and nerve. [1,4].
Internal carotid artery dissection Isolated unilateral hypoglossal nerve lower motor type palsy due to damage of the peripheral hypoglossal nerve when travels close to internal carotid artery [2,3].
References
  1. Gelb, D., Aminoff, M., & Wilterdink, J. (2012, September 7). The detailed neurologic examination in adults. Retrieved September 22, 2014, from file:///E:/Studies/uptodate 21.2/contents/mobipreview.htm?37/30/38377#H32
  2. FUJII H, OHTSUKI T, TAKEDA I, HOSOMI N, MATSUMOTO M. Isolated unilateral hypoglossal nerve paralysis caused by internal carotid artery dissection. J Stroke Cerebrovasc Dis [online] 2014 Sep, 23(8):e405-6 [viewed 22 September 2014] Available from: doi:10.1016/j.jstrokecerebrovasdis.2014.03.004
  3. Adams HP Jr, del Zoppo G, Alberts MJ, et al. Guidelines for the early management of adults with ischemic stroke: a guideline from the American Heart Association/American Stroke Association Stroke Council, Clinical Cardiology Council, Cardiovascular Radiology and Intervention Council, and the Atherosclerotic Peripheral Vascular Disease and Quality of Care Outcomes in Research Interdisciplinary Working Groups: the American Academy of Neurology affirms the value of this guideline as an educational tool for neurologists. Stroke 2007; 38:1655.
  4. Oliveira-Filho ,, J., Koroshetz, W., Kasner, J., & Dashe, S. (2013, April 9). Initial assessment and management of acute stroke. Retrieved September 22, 2014, from file:///E:/Studies/uptodate 21.2/contents/mobipreview.htm?32/29/33242/abstract/14
  5. SAYAN A, ABEYSINGHE AH, BRENNAN PA, ILANKOVAN V. Persistent idiopathic unilateral hypoglassal nerve palsy: a case report. Br J Oral Maxillofac Surg [online] 2014 Jul, 52(6):572-4 [viewed 25 September 2014] Available from: doi:10.1016/j.bjoms.2014.04.005

Investigations - for Diagnosis

Fact Explanation
Non contrast CT brain To exclude haemorrhagic stroke in the acute setting and arrive at the diagnosis [1,2].
Blood sugar Exclude hypoglycaemia mimicking stroke [1].
MRI scan of brain Identify the tumours and other space occupying lesions [1,2].
Serum electrolytes To exclude metabolic causes for stroke like SIADH secretion in head injury and subarachnoid haemorrhage, hypotension in Addison's disease as well as hypertension in Conn's disease[4-6].
Carotid artery Doppler To exclude arterial source of thrombus [1,2].
Echocardiogram To exclude cardiac source of thrombus [1,2].
ECG Important for detecting signs of concomitant acute cardiac ischemia [1-3].
References
  1. Oliveira-Filho ,, J., Koroshetz, W., Kasner, J., & Dashe, S. (2013, April 9). Initial assessment and management of acute stroke. Retrieved September 22, 2014, from file:///E:/Studies/uptodate 21.2/contents/mobipreview.htm?32/29/33242/abstract/14
  2. European Stroke Organisation (ESO) Executive Committee, ESO Writing Committee. Guidelines for management of ischaemic stroke and transient ischaemic attack 2008. Cerebrovasc Dis 2008; 25:457.
  3. FUJII H, OHTSUKI T, TAKEDA I, HOSOMI N, MATSUMOTO M. Isolated unilateral hypoglossal nerve paralysis caused by internal carotid artery dissection. J Stroke Cerebrovasc Dis [online] 2014 Sep, 22(8):e405-6 [viewed 25 September 2014] Available from: doi:10.1016/j.jstrokecerebrovasdis.2014.03.004
  4. HILTON-JONES DAVID, WARLOW CHARLES P.. The causes of stroke in the young. J Neurol [online] 1985 July, 232(3):137-143 [viewed 26 September 2014] Available from: doi:10.1007/BF00313888
  5. MIRó O, PASTOR P, PEDROL E, MALLOFRé C, GRAU JM, CARDELLACH F. [Cerebral vascular complications in Conn's disease: report of two cases]. Neurologia [online] 1995 May, 10(5):209-11 [viewed 26 September 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/7619540
  6. NERUP J, BENDIXEN G. Anti-adrenal cellular hypersensitivity in Addison's disease. II. Correlation with clinical and serological findings Clin Exp Immunol [online] 1969 Oct, 5(4):341-353 [viewed 26 September 2014] Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1579128

Investigations - Fitness for Management

Fact Explanation
FBC As baseline investigation of haematological function [1,2].
Chest X-ray Required for assessment of general health and related respiratory function as well as complications of stroke like aspirations and it is important if they may need surgical intervention for intracranial haemorrhage(a routine preoperative chest X-ray should be available in all elderly surgical patients(age > 65 years) (a) as a baseline measurement and (b) to exclude unsuspected disease) [3].
Serum creatinine Baseline renal function before starting long term medication[3].
AST/ALT As patient required long term medication it is important to have baseline liver function [1,3].
ECG Cardiac fitness or previous ischaemic events as cerebrovascular disease associated with concomitant coronary artery disease [1].
PT/INR When considering acute ischaemic stroke PT/INR may be important to consider when giving thrombolytic therapy. As high INR >1.7 is a relative contraindication for thrombolysis [2].
Blood pressure When considering acute ischaemic stroke blood pressure may be important to consider when giving thrombolytic therapy. As high blood pressure is contraindicated for thrombolysis( systolic >185 mmHg or diastolic >110 mmHg ) [2,5].
References
  1. European Stroke Organisation (ESO) Executive Committee, ESO Writing Committee. Guidelines for management of ischaemic stroke and transient ischaemic attack 2008. Cerebrovasc Dis 2008; 25:457.
  2. Oliveira-Filho ,, J., Koroshetz, W., Kasner, J., & Dashe, S. (2013, April 9). Initial assessment and management of acute stroke. Retrieved September 22, 2014, from file:///E:/Studies/uptodate 21.2/contents/mobipreview.htm?32/29/33242/abstract/14
  3. Jauch EC, Saver JL, Adams HP Jr, et al. Guidelines for the early management of patients with acute ischemic stroke: a guideline for healthcare professionals from the american heart association/american stroke association. Stroke 2013; 44:870.
  4. SEYMOUR DG, PRINGLE R, SHAW JW. The role of the routine pre-operative chest X-ray in the elderly general surgical patient Postgrad Med J [online] 1982 Dec, 58(686):741-745 [viewed 26 September 2014] Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2426605
  5. FUJII H, OHTSUKI T, TAKEDA I, HOSOMI N, MATSUMOTO M. Isolated unilateral hypoglossal nerve paralysis caused by internal carotid artery dissection. J Stroke Cerebrovasc Dis [online] 2014 Sep, 23(8):e405-6 [viewed 25 September 2014] Available from: doi:10.1016/j.jstrokecerebrovasdis.2014.03.004

Investigations - Followup

Fact Explanation
CT brain If the initial CT scan was normal to identify the ischaemic area after 48 hours of onset of symptoms [1].
Serum creatinine Monitoring renal function as patient is on medications for long time [1,2].
AST/ALT Monitoring liver function as patient is on medications for long time [2].
References
  1. Jauch EC, Saver JL, Adams HP Jr, et al. Guidelines for the early management of patients with acute ischemic stroke: a guideline for healthcare professionals from the american heart association/american stroke association. Stroke 2013; 44:870.
  2. Oliveira-Filho ,, J., Koroshetz, W., Kasner, J., & Dashe, S. (2013, April 9). Initial assessment and management of acute stroke. Retrieved September 22, 2014, from file:///E:/Studies/uptodate 21.2/contents/mobipreview.htm?32/29/33242/abstract/14

Investigations - Screening/Staging

Fact Explanation
Blood pressure When considering acute ischaemic stroke blood pressure may be important to consider when giving thrombolytic therapy. As high blood pressure is contraindicated for thrombolysis( systolic >185 mmHg or diastolic >110 mmHg ) [1,2].
Blood sugar Before giving thrombolysis it is necessary to exclude hypoglycaemia as well as diagnosis of underlying diabetes mellitus[1,3].
Clinical examination of nervous system To have objective measure of neurological deficit prior starting thrombolysis [1].
References
  1. Oliveira-Filho ,, J., Koroshetz, W., Kasner, J., & Dashe, S. (2013, April 9). Initial assessment and management of acute stroke. Retrieved September 22, 2014, from file:///E:/Studies/uptodate 21.2/contents/mobipreview.htm?32/29/33242/abstract/14
  2. FUJII H, OHTSUKI T, TAKEDA I, HOSOMI N, MATSUMOTO M. Isolated unilateral hypoglossal nerve paralysis caused by internal carotid artery dissection. J Stroke Cerebrovasc Dis [online] 2014 Sep, 23(8):e405-6 [viewed 25 September 2014] Available from: doi:10.1016/j.jstrokecerebrovasdis.2014.03.004
  3. European Stroke Organisation (ESO) Executive Committee, ESO Writing Committee. Guidelines for management of ischaemic stroke and transient ischaemic attack 2008. Cerebrovasc Dis 2008; 25:457.

Management - General Measures

Fact Explanation
Resuscitation Stabilization of airway, breathing, and circulation, and rapid neurologic evaluation to treat early complications of stroke [1].
Correction of hypoglycaemia if present Hypoglycemia can cause focal neurologic deficits mimicking stroke, and severe hypoglycemia alone can cause neuronal injury, an early identification and treatment may prevent progression of deficit [1].
Assessment of swallowing difficulties Dysphagia is common after stroke and is a major risk factor for developing aspiration pneumonia. It is important to assess swallowing function prior to administering oral medications or food. May require nasogastric tube for feeding [1,2].
Antipyretics Patient with cerebral abscess, meningitis, subdural empyema, aspiration pneumonia or urinary tract infection secondary to catheterization may have fever. Control of fever necessary for preventing further cerebral damage. [1,3].
Blood pressure management pecial considerations apply to blood pressure control in patients with acute ischemic stroke who are eligible for thrombolytic therapy. Before lytic therapy is started, treatment is recommended so that systolic blood pressure is ≤185 mmHg and diastolic blood pressure is ≤110 mmHg [1,4].
Speech therapy Early physiotherapy and speech therapy accelerate the improvement of neurological deficit [2].
Measures to prevent aspiration pneumonia High risk of aspiration associated with swallowing difficulty. Early insertion of nasogastric tube is necessary in patient with swallowing difficulties [1,2].
Antiepileptics Some with ischaemic and more with haemorrhagic stroke may develop seizures. If a seizure occurs, appropriate intravenous antiepileptic drug (AED) treatment should be administered to prevent recurrent seizures [1].
Statins Intensive lipid-lowering therapy with a statin is associated with a reduced risk of recurrent stroke and cardiovascular events [2,3].
Neuroprotective compounds Evidence shows neuroprotective compounds reduce the size of infarction and prevent ischaemic neuronal cell death within ischaemic penumbra [5,6].
References
  1. Oliveira-Filho ,, J., Koroshetz, W., Kasner, J., & Dashe, S. (2013, April 9). Initial assessment and management of acute stroke. Retrieved September 22, 2014, from file:///E:/Studies/uptodate 21.2/contents/mobipreview.htm?32/29/33242/abstract/14
  2. Jauch EC, Saver JL, Adams HP Jr, et al. Guidelines for the early management of patients with acute ischemic stroke: a guideline for healthcare professionals from the american heart association/american stroke association. Stroke 2013; 44:870.
  3. European Stroke Organisation (ESO) Executive Committee, ESO Writing Committee. Guidelines for management of ischaemic stroke and transient ischaemic attack 2008. Cerebrovasc Dis 2008; 25:457.
  4. Morgenstern LB, Hemphill JC 3rd, Anderson C, et al. Guidelines for the management of spontaneous intracerebral hemorrhage: a guideline for healthcare professionals from the American Heart Association/American Stroke Association. Stroke 2010; 41:2108.
  5. BERAKI S, LITRUS L, SORIANO L, MONBUREAU M, TO LK, BRAITHWAITE SP, NIKOLICH K, URFER R, OKSENBERG D, SHAMLOO M. A Pharmacological Screening Approach for Discovery of Neuroprotective Compounds in Ischemic Stroke PLoS One [online] , 8(7):e69233 [viewed 26 September 2014] Available from: doi:10.1371/journal.pone.0069233
  6. WANG JK, PORTBURY S, THOMAS MB, BARNEY S, RICCA DJ, MORRIS DL, WARNER DS, LO DC. Cardiac glycosides provide neuroprotection against ischemic stroke: discovery by a brain slice-based compound screening platform. Proc Natl Acad Sci U S A [online] 2006 Jul 5, 103(27):10461-6 [viewed 26 September 2014] Available from: doi:10.1073/pnas.0600930103

Management - Specific Treatments

Fact Explanation
Intravenous thromboysis Who presents within 3h of onset of neurological deficit and have ischaemic stroke (haemorrhage excluded by non contrast CT brain) may be a candidate for intravenous thrombolysis if other eligible criteria are met.(Inclusion criteria - Clinical diagnosis of ischemic stroke causing measurable neurologic deficit/ Onset of symptoms <4.5 hours before beginning treatment; if the exact time of stroke onset is not known, it is defined as the last time the patient was known to be normal/ Age ≥18 years ) [1,2].
Antithrombotics For patients with ischaemic stroke may beneficial from antithrombotics to prevent progression of thrombus. [1-3].
References
  1. European Stroke Organisation (ESO) Executive Committee, ESO Writing Committee. Guidelines for management of ischaemic stroke and transient ischaemic attack 2008. Cerebrovasc Dis 2008; 25:457.
  2. Jauch EC, Saver JL, Adams HP Jr, et al. Guidelines for the early management of patients with acute ischemic stroke: a guideline for healthcare professionals from the american heart association/american stroke association. Stroke 2013; 44:870.
  3. Oliveira-Filho ,, J., Koroshetz, W., Kasner, J., & Dashe, S. (2013, April 9). Initial assessment and management of acute stroke. Retrieved September 22, 2014, from file:///E:/Studies/uptodate 21.2/contents/mobipreview.htm?32/29/33242/abstract/14