Falling and Forgetting

Dr TC ChanDr LW ChuInter-hosipitalGeriatric Meeting29-5-2009

Case 1

Mr A• 86/M• ADL-I

• Walk unaided• Live with family

• Non smoker non drinker• Good past health

• Attend A&E 10/2008 due to slip and fall at home

• Non-syncopal• Landed on buttock • P/E

– BP 117/60– P 63 regular– CNS examination: unremarkable with full

power in all limbs

• Pelvic X ray: no fracture• discharged, walk unaided

• Attend A&E 11/2008 due to slip and fall at home again

• Non-syncopal

• Diagnosis: minor Head injury• Discharged after suture done

• Attend A&E 4/2009 due to non-syncopal slip and fall at home AGAIN

• Landed on forehead• P/E forehead haematoma with 1cm diameter• Admitted Division of Head & Neck of

Department of surgery

• In view of recurrent falls– H&N colleague consult our Geriatrics team

• for assessment of repeated falls • and plan for rehabilitation

• Brief history from patient– Non-syncopal fall– Unsteady gait

• No weakness over limbs– Not on any medications / OTC med / TCM

• P/E– GCS 15/15– Orientated to place and person, but not to exact time– BP 120/80, no significant postural drop– P 80 regular– CVS, abd, Resp: NAD– CNS:

• Cranial nerve intact, no ophthalmoplegia• Power 5/5 over 4 limbs• Jerk normal• Downgoing plantar• NO tremor, rigidity or bradykinesia• NO cerebellar sign• NO sensation impairment

• Then look at his gait…

What can you observe from this video?What will you do next?

• Gait– Wide base gait– Toe out– Poor feet clearance– Outstretched hand– Fear to fall on turning– Presence of hand swing

– � magnetic gait / gait apraxia

• History from son– Unsteady gait for >6 months

• Walk unaided � walk with quad � nearly chair bound

– Cognitive impairment for >1 year• Gradual onset, STM affected more, repeated

questioning, misplaced object• BADL need mild assistance• IADL need major assistance• Some disorientation to time, well preserved in

place and person• More and more irritable

What are the differential diagnosis?

• DDx– Vascular dementia (subcortical subtype) – Lewy Body Dementia (LBD)– Parkinson disease with dementia (PDD)– Normal pressure hydrocephalus (NPH)– Coexistence of Alzheimer Disease (AD) and

NPH

– No incontinence history• But frequency or urination

– No visual hallucination– No family history of neurodegenerative

disease

• Investigation– CBP– RFT – VDRL– B12, folate– TFT

• CT findings– No feature of haematoma– Mild disproportionate dilatation of the lateral

and 3 rd ventricle when compared with that of the cerebral sulci

– Evan’s ratio 0.42– Periventricular hypodensity with extension to

subcortical white matter– Features of lacunar infarcts

• Definition of ventriculomegaly– Evan’s ratio > 0.31– Maximal diameter of

the frontal horns of the lateral ventricles/ maximum width of the cranial cavity inthe same plane

• In view of highly suspicious of normal pressure hydrocephalus clinically – Takeover to medical/Geriatrics for further

management

Lumbar tap test (LTT)

• Videotape + Multidisplinary assessment of patient for cognitive function and gait before and after that

• 3 hours after Lumbar tap test

Functional assessment

124Tinetti gait12

1612MMSE

2510Tinetti total 28

136Tinetti balance16

3818BBS 56

After LTTBefore LTT

BBS: Beig Balance Scale MMSE: Mini mental state examination

• Berg Balance scale– A 14-tem scale designed to measure balance

of the older adult in a clinical setting– 0-20: high fall risk– 21-41: medium fall risk– 42-56: low fall risk

• Tinetti test– Performance oriented mobility assessment– Balance and gait

• MMSE (mini mental state examination)– Cognitive screening test– Orientation, registration, attention and

calculation, recall, language, copy– Cut off point

• No education: 18• 1-2 years education: 20• >2 years education: 22

• Working Diagnosis– NPH

• Consult neurosurgeon – for consideration of shunting

• Neurosurgeon assessment– Agree about the diagnosis of NPH– Takeover for further management

• After repeated interview between neurosurgeon and relative– Decided not for shunting or further LP

• GA risk• Potential VP shunt complication• Possibility that dementia may not improve

after operation

• Transferred to Fung Yiu King Hospital for rehabilitation

• On discharge– Walk with quadripod indoor– MMSE 14/30– Basic activity of daily living (BADL) minimal

assistance

• For further day rehabilitation after discharge

Normal pressure hydrocephalus (NPH)

• Definition– Pathologically enlarged ventricular size– With normal opening pressure on LP

• Epidemiology– 2 – 20 per million per year– Most common over 60

• Classification– Idiopathic– Secondary

• E.g. history of subarachnoid haemorrhage, chronic meningitis

• Main pathological change– Decrease CSF reabsorption

• Possible cause– Arachnoid fibrosis (50%)– Increase venous resistance due to

periventricular ischemia – Underlying incompetence of jugular valves

cause retrograde flow in the IJV (95% vs 25%)

• Clinical features– Adam’s triad (1965)

N Eng J Med• Dementia• Gait disturbance• Urinary incontinence

• Gait difficulty– Most prominent clinical

feature in early stage of NPH in most cases

– Magnetic gait / gait apraxia / frontal ataxia

– Patient’s feet “stuck” to the flow

• Markedly similar to Parki gaibut with a specific broadened base with outwardly rotated feet

• Cognitive Impairment– Prominent subcortical and

frontal features• Psychomotor slowing• Decreased attention and

concentration• Apathy• Impaired executive function• Cortical features less

prominent (aphasia, agnosia, apraxia)

• Urinary incontinence– Urgency may be present at early stages– Incontinence at late stages

NPHClinical symptoms• Distortion of the central portion of the corona

radiata by the distended ventricles, including– sacral motor fibers that innervate the legs and

the bladder, thus explaining the abnormal gait and incontinence

– dementia results from distortion of the periventricular limbic system.

• Other possible features– Long tract signs (UMN sign)– Parkinsonism– Akinetic mutism– quadriparesis

• Coexistence of AD and NPH– 26% – 61%– Presence of AD correlate with degree of

cognitive impairment– Implication for the response to treatment

J Neurol Neurosurg Psychiatry 2000Neurosurgery 1997 Mar

What are the different investigations and Is

MRI flow study useful?

• Investigation– Imaging– Procedure (CSF) related

• Imaging– MRI– CT

• MRI allow visualization of other markers of NPH � white matter change, vascular change

– MRI flow study

• Key findings– Ventriculomegaly– White matter lesion

• Ventriculomegaly• In the absence of, or out of proportion to,

sulcal enlargement• But if with presence of sulcal enlargement � age related change (Hydrocephalus ex vacuo) / cerebral atrophy� coexistance of AD

• Definition of ventriculomegaly– Evan’s ratio > 0.31– Maximal diameter of

the frontal horns of the lateral ventricles/ maximum width of the cranial cavity inthe same plane

• White matter lesion (MRI)– Characteristic high signal abnormality around

the ventricles– Usually correlate with degree of cognitive

impairment

• MRI flow study– decreased attenuation in the aqueduct of Sylvius �

aqueduct flow void – represent higher than normal flow velocity of

cerebrospinal fluid (CSF) in the aqueduct

• MRI flow study– Most latest studies show

• No difference between flow study for patient with NPH and age matched controls

Neurosurgery 1997, 2001

• Poor correlation with postoperative outcome after shunting

AJNR Am J Neuroradiol 2001 Radiology. 2001

– Low sensitivity, low specificity, low positive predictive value and low negative predictive value

• Procedure (CSF) related– Lumbar tap test– Lumbar drainage– Intracranial pressure monitoring

• Lumbar tap test / Fisher test– LP– 30 – 50ml of CSF removed– Documentation before and 30-60 minutes

after the procedure for• Gait speed, stride length, reaction time, test of

verbal memory and visual attention (PT + OT)• Videotape of gait before and after the tap• Feedback from the patient and family for

subjective improvement

• Lumbar tap test– Sensitivity: 30-50%– Specificity: 60-80%– Positive predictive value: 90-100%– Negative predictive value: 30-50%

Neurosurgery. 2001J Neurol Neurosurg Psychiatry. 2002 J Neurol Neurosurg Psychiatry. 2002

• Lumbar drainage– Temporary catheter in lumbar CSF space– Continuous CSF drainage at a rate of 5-

10ml/hour for 2-7 days– Sensitivity: 60-80%– Specificity: 80-90% (small series)

Neurosurgery. 1988– But associated with more complications

• Meningitis, SDH

• Intracranial pressure monitoring– Prolonged pressure monitoring via an

intracranial transducer may reveals• Intermittent rhythmic pressure deviations or B

waves (0.5 to 2/min ossicilations)• Basal ICP may greater than 5 to 10mmHg

– Invasive and lack of normative criteria – Sensitivity 70-80%– Specificity 60-70%

What are the treatment a/v and should we perform shunting in all patient?

• Treatment– Medical– Surgical

• Repeated high volume taps • Shunting

• Medical– Acetazolamide– Reduce production of CSF by 30-50%– Have not been shown to be effective

• Repeated high volume taps – NO published study / data– Only case reports

• Shunting– Drainage site

• Ventriculoperitoneal (more common)• Ventriculoatrial

– Type• Standard valves with low, medium or high

pressure system• Programmable valve (which allow pressure

adjustments without re-operation)

• Outcome of shunting– 59% improved after surgery on at least one major

symptom• Gait is most responsive (50-70%)• Urinary incontinence is very responsive (45-55%)• Cognitive impairment

– Most study show limited improvement in most case

– <20%

– Co-existance of AD?J Neurol. 2000

Neurosurgery 2001

• Shunt complications– Overall 38%

• SDH, subdural effusion most common ~10%– 6% resulted in permanent neurologic

sequelae or death– 1/5 need second surgery in 1 year– ½ need shunt revision in 6 year…

• Predictors of shunt efficacy– Favorable indicators

• Early appearance of gait disorder• Gait disorder most prominent symptom• Shorter duration of symptoms (< 6 months)• Identified etiology of NPH• Positive finding in lumbar tap test / lumber

drainage test

• Unfavorable indicators– Early appearance of dementia– Moderate to severe dementia– Dementia present for > 2 years– Gait disorder absent– Alcoholism– MRI findings

• Marked white matter disease• Diffuse sulcal enlargement• Medial temporal atrophy

Go back to our patient• History, physical examination and investigation

– Working diagnosis of NPH

• Mx: conservative due to presence of multiple unfavorable indicator � moderate dementia� early appearance of dementia and > 1yearin duration� GA risk