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*For medical professionals only
In fact, what we often call "Alzheimer's disease", that is, Alzheimer's disease, is the main type of
dementia.
However, there is a disease that is very similar to the symptoms of Alzheimer's disease, and it is easy to misdiagnose due to lack of experience, so let's take a look
together.
The patient, Zhou, female, 74 years old, retired worker
.
Fig.
1 CT of the head before the visit showed that the third ventricle was enlarged, and the lateral fissure widened
, so the cerebrospinal fluid drainage test was performed, and 40ml
of fluid was discharged.
Compared with before discharge, the patient's mental state improved after discharge, verbal communication increased, muscle tone decreased compared with before, gait speed and stride length increased, stride width decreased, and slowness of movement improved compared with before
.
Fig.
2 (from literature [1]) Common
causes of
hydrocephalus ▌Cerebrospinal fluid circulation channel is blocked
Congenital malformations (the most common cause in term infants): congenital occlusion of the midbrain aqueduct caused by X chromosome gene deletion, arachnoid granulosis hypoplasia, cerebellar tonsillar hernia obstruction of the fourth ventricle outflow, fourth ventricular foramen occlusion syndrome obstruction of the fourth ventricle outflow tract, spina bifida
。
Post-inflammatory adhesions: arachnoid
caused by toxoplasmosis or viral bacterial infection during pregnancy.
Mass lesion compression: congenital cysts / tumors, etc
.
Post-hemorrhagic adhesions: fibroplasia or arachnoid adhesions after trauma or spontaneous ventricular/subarachnoid hemorrhage can affect cerebrospinal fluid circulation and cause hydrocephalus
.
Post-inflammatory adhesions: such as purulent meningitis, tuberculous meningitis, ventriculitis, etc.
, due to the proliferation of fibrous tissue blocking the circulatory pores of cerebrospinal fluid, especially in the fourth ventricular foramen and subarachnoid adhesions at the bottom of the brain and hydrocephalus
.
Compression of mass lesions: Mass lesions such as intracranial cysts/tumors/hemorrhages can block any part of the cerebrospinal fluid circulation pathway, and are more common near
the fourth ventricle.
▌Cerebrospinal fluid secretion is
rare and mostly congenital
.
Common causes: choroid plexus hyperplasia, choroid plexus papilloma, or carcinoma
.
Special findings: radiographic hyperplasia of the choroid plexus or significant intraventricular mass.
▌Cerebrospinal fluid absorption disorders
such as fetal meningitis and cerebrospinal fluid absorption disorders occur due to hydrocephalus
.
The classification
of hydrocephalus "Expert consensus on the diagnosis and treatment of idiopathic normal pressure hydrocephalus in China (2016 edition)" classifies hydrocephalus as follows : According to pathological classification:
obstructive hydrocephalus, communicating hydrocephalus, external hydrocephalus
.
Classified according to etiology: traumatic hydrocephalus, otogenic hydrocephalus, infectious hydrocephalus, mass hydrocephalus, hemorrhagic hydrocephalus
.
Classified according to the rate of onset: acute hydrocephalus, chronic hydrocephalus, normal pressure hydrocephalus, resting hydrocephalus
.
Classification by age: infantile hydrocephalus
, older children and adults.
Clinical manifestations of normal pressure hydrocephalus Typical clinical manifestations
of normal pressure hydrocephalus are gait disturbance, cognitive impairment, and urinary incontinence
。 Among them, gait disorders are the most common, cognitive impairment and urinary incontinence also occur to varying degrees, and about half of patients have triad at the same time
.
Gait disorders: gait disorders are often manifested as slow walking, unstable rocking, small stride distance, widening of foot spacing, smaller foot height, starting and turning obstacles, but normal
arm swing function when walking.
In the early stages of the disease, gait disturbances are mild and imperceptible, often complaining
of "dizziness".
As the disease progresses, typical gait disturbances manifest gradually
.
In advanced disease, patients need assistance to walk, or even not at
all.
Some patients have clinical manifestations similar to parkinsonism.
Cognitive impairment: Cognitive impairment of normal stress hydrocephalus is part of neuropsychological impairment and involves cognitive, emotional, and psychobehavioral aspects
.
Clinical manifestations are psychomotor retardation, apathy, emotional apathy, attention, memory, calculation, visuospatial function and executive dysfunction, etc.
, patients lack initiative and active communication ability, the above conditions may fluctuate, or short-term aggravation
.
Patients with reduced ability to perform daily living are one of the common types of dementia in clinical practice, and such patients have the possibility of recovery of cognitive dysfunction, so it is called reversible dementia
.
Urinary incontinence: bladder dysfunction of normal pressure hydrocephalus is neurogenic and accompanied by detrusor hyperactivity, which can be seen in the vast majority of patients with
normal pressure hydrocephalus.
Urinary frequency and urgency can occur early in the disease, and as the disease progresses, complete urinary incontinence may occur, even fecal incontinence, and urinary retention
may occur.
Diagnostic criteria
for normal pressure hydrocephalus are clinical findings and imaging findings that are necessary for the diagnosis of normal pressure hydrocephalus
.
However, given the complexity of diagnosing normal pressure hydrocephalus, there are three diagnostic levels of normal pressure hydrocephalus: clinically suspected, clinically diagnosed, and clinically confirmed
.
■ Clinically suspicious: (1) Adults have a slow onset and gradual worsening, and symptoms can fluctuate to aggravate or resolve; clinically present with at least 1 symptom of the triad of typical gait impairment, cognitive dysfunction, and urinary incontinence;
(2) Imaging shows ventricular enlargement, Evan's index > 0.
3, and no other causes of ventricular enlargement;
there may be (or) no low density around the ventricle (CT) or hyperintensity (T2-weighted image on MRI);
Coronal imaging shows signs of "subarachnoid incuncanes";
(3) Lumbar puncture (lateral decubitus position) or intracranial pressure monitoring in the ventricle confirmed that intracranial pressure ≤ 200mmH2O, and cerebrospinal fluid routine and biochemical examination were normal;
(4) Clinical, imaging and biochemical examinations exclude the existence of
other neurological and non-nervous system diseases that may cause the above clinical manifestations.
■ Clinical diagnosis: (1) Meet the diagnostic criteria for clinical suspicion of normal pressure hydrocephalus;
(2) Those who meet one of the following criteria at the same time:
(1) Symptoms improve after cerebrospinal fluid drainage test;
(2) Symptoms improved
after continuous cerebrospinal fluid drainage test.
■Clinical diagnosis:
Patients with clinical suspicion or clinical diagnosis, patients whose efficacy has improved significantly after surgical intervention of cerebrospinal fluid shunt surgery are confirmed
.
Differentiation
of normal pressure hydrocephalus and key points of normal pressure hydrocephalus and Alzheimer's disease:
Table 1 Identification points (as </b20 <b21>>Original)
Evaluation
of normal pressure hydrocephalus ■ Gait disorder evaluation:
(1) 10m walking test: according to the state of daily walking or auxiliary state, the time and number of
steps required for 10m straight line walking are measured.
After the drainage test, if one parameter is improved by more than 20%, or if both parameters are improved by more than 10%, it is positive
.
(2) 5m switchback walking test: measure the time and number of
steps required to stand up from the chair, walk in a straight line for 5m, and then return to sit.
After cerebrospinal fluid drainage or surgery, the regression walking test improves by more than 10% to be positive
.
In addition, it is difficult to close the eyes before releasing the liquid, or strengthen the test and evaluation
of closing the eyes and walking in a row.
■Cognitive impairment assessment:
MMSE or MoCA is recommended for cognitive dysfunction screening
。 This method is relatively rough, it is recommended to conduct connection test, number symbol, listening word memory test and jack test, and it is recommended to carry out emotional behavior evaluation and daily living ability evaluation to establish a comprehensive cognitive function evaluation, which is helpful to determine the degree of
cognitive function improvement.
An increase in MMSE score of more than 3 points is a positive result
.
■Voiding dysfunction: Voiding dysfunction questionnaire:
Patients and caregivers can be asked
about the questionnaire and scored according to the severity and frequency of occurrence.
■Overall Living Capacity Assessment:
Daily Living Abilities (ADL) is recommended Assessed
on scales and modified stroke quality of life rating scales.
Surgical treatment of normal pressure hydrocephalus At present, it has been confirmed that surgical treatment is an effective treatment
measure for normal pressure hydrocephalus, and various shunt surgeries, especially ventriculoperitoneal shunting, are the most common.
Early surgery can significantly improve the patient's condition and prognosis
.
Indications: Once the diagnosis of normal pressure hydrocephalus is made, it can be treated with surgery as soon as possible
after full evaluation and clinical diagnosis.
Contraindications: severe underlying diseases that cannot tolerate surgery, coagulation dysfunction that cannot be clinically corrected, intracranial infection, shunt channel infection, abdominal infection, etc
.
Surgical methods: mainly include: ventriculoperitoneal shunt, ventricular atrial shunt, lumbar pool abdominal shunt, etc
.
Ventriculoperitoneal shunting is the main operation
.
Figure 3 (from literature [1]) Meta-analysis
of the Japanese Society of Neurosurgery [4].
It was noted that symptom improvement in patients with normal pressure hydrocephalus ranged from 31% to 2 years after shunt surgery, and 61% to 91% improved symptoms in patients with follow-up for 3 to 5 years
.
Among them, the improvement rate of gait instability reached 58%-90%, the improvement rate of cognitive dysfunction was 29%-80%, and the improvement rate of urinary incontinence was 20%-78%.
US guidelines for idiopathic normal pressure hydrocephalus [5] indicate that symptoms such as dementia, gait instability, and urinary incontinence can be significantly improved
in 72% to 80% of patients after shunting.
It is clinically difficult to determine the course of normal pressure hydrocephalus due to comorbidities, but patients with normal pressure hydrocephalus who do not receive treatment tend to progress rapidly
.
In short, the symptoms of dementia and urinary incontinence often caused by normal intracranial pressure hydrocephalus are very similar to Alzheimer's disease, and many people are easily confused
.
Alzheimer's disease is an irreversible Alzheimer's disease, and normal pressure hydrocephalus can be treated surgically, and CT is repeated after 3 months, and if symptoms do not improve and the ventricles are still enlarged, a lower pressure shunt can be considered
.
After treatment, the patient's quality of life will also be significantly improved, and cognitive function will gradually improve
.
In general, the earlier the diagnosis, the greater
the chances of successful treatment.
Where to see more Alzheimer's knowledge?
Come to the "Doctor Station" and take a look 👇
Are cognitive decline, bradykinesia, and urinary incontinence dementia? Don't miss this cause!
In fact, what we often call "Alzheimer's disease", that is, Alzheimer's disease, is the main type of
dementia.
However, there is a disease that is very similar to the symptoms of Alzheimer's disease, and it is easy to misdiagnose due to lack of experience, so let's take a look
together.
Let's look at the case data first
The patient, Zhou, female, 74 years old, retired worker
.
- Complaints: Delayed movement for more than 5 years, aggravated by 3 months
.
- Current medical history: the patient's family complained that 5 years ago the patient found that the patient was slow to move, mainly manifested as slow walking, and easy to fall, and then had difficulty turning over, difficulty getting up, and could not take care
of himself.
3 years ago, he began to have incontinence, long-term bed rest, apathy, unresponsiveness, manifested as memory, calculation, time, space and orientation decline, once in the local hospital to consider "Parkinson's disease", given dopasrazide tablets, carvodopa controlled-release tablets and other drugs, symptoms have not improved
significantly.
The above symptoms began to worsen 3 months ago, salivation at the corners of the mouth, choking on water, and difficulty
swallowing.
Because the symptoms continued to not alleviate, he was admitted to our department
.
Physical examination: T 36.
3 °C, P 66 times/min, R 20 times/min, BP 160/86mmHg
.
Clear, speechless, bilateral pupils are equally large, 3.
0mm in diameter, light response exists, binocular movement in all directions, no diplopia and nystagmus, bilateral nasolabial folds are symmetrical, tongue extension is not cooperative, lower limbs have a little autonomous movement, high muscle tone in the limbs, heavier upper limbs than lower limbs, high trunk muscle tone, active bilateral tendon reflexes, positive bilateral Pap sign, negative meningeal stimulation sign, Glasgow score (GCS) score 8 points
。 The step base is slightly wider, one step can be completed, and the post-pull test is negative
.
Cognitive function is significantly reduced and cannot be measured
with the Miniature Mental Status Test (MMSE) or the Montreal Cognitive Assessment (MOCA) scale.
Anamnesis: history of hypertension for more than 10 years
.
The highest hypertension is 199/100mmHg, and nifedipine controlled-release tablets are taken 30mg 1/day to control blood pressure
.
Cerebral infarction for more than 10 years, take aspirin enteric-coated tablets 0.
1g 1 / day, atorvastatin 20mg 1 / day
.
Auxiliary examination:
1.
Head MRI showed that the third ventricle was enlarged, the lateral fissure was widened, and the frontal angle ratio (Evan's index) was > 0.
33
.
2.
Cerebrospinal fluid pressure 140mmH2O, cerebrospinal fluid colorless, clear and transparent, white blood cells 0.
001 x109/L, L 0.
70, M 0.
30, protein qualitative (-), sugar 4.
33mmol/L, total protein 0.
4g/L, chloride 120.
1mmol/L
.
- Diagnosis: normal pressure hydrocephalus
.
Fig.
1 CT of the head before the visit showed that the third ventricle was enlarged, and the lateral fissure widened
, so the cerebrospinal fluid drainage test was performed, and 40ml
of fluid was discharged.
Compared with before discharge, the patient's mental state improved after discharge, verbal communication increased, muscle tone decreased compared with before, gait speed and stride length increased, stride width decreased, and slowness of movement improved compared with before
.
Fig.
2 (from literature [1]) Common
causes of
hydrocephalus ▌Cerebrospinal fluid circulation channel is blocked
- Congenital causes:
Congenital malformations (the most common cause in term infants): congenital occlusion of the midbrain aqueduct caused by X chromosome gene deletion, arachnoid granulosis hypoplasia, cerebellar tonsillar hernia obstruction of the fourth ventricle outflow, fourth ventricular foramen occlusion syndrome obstruction of the fourth ventricle outflow tract, spina bifida
。
Post-inflammatory adhesions: arachnoid
caused by toxoplasmosis or viral bacterial infection during pregnancy.
Mass lesion compression: congenital cysts / tumors, etc
.
- Acquired causes:
Post-hemorrhagic adhesions: fibroplasia or arachnoid adhesions after trauma or spontaneous ventricular/subarachnoid hemorrhage can affect cerebrospinal fluid circulation and cause hydrocephalus
.
Post-inflammatory adhesions: such as purulent meningitis, tuberculous meningitis, ventriculitis, etc.
, due to the proliferation of fibrous tissue blocking the circulatory pores of cerebrospinal fluid, especially in the fourth ventricular foramen and subarachnoid adhesions at the bottom of the brain and hydrocephalus
.
Compression of mass lesions: Mass lesions such as intracranial cysts/tumors/hemorrhages can block any part of the cerebrospinal fluid circulation pathway, and are more common near
the fourth ventricle.
▌Cerebrospinal fluid secretion is
rare and mostly congenital
.
Common causes: choroid plexus hyperplasia, choroid plexus papilloma, or carcinoma
.
Special findings: radiographic hyperplasia of the choroid plexus or significant intraventricular mass.
▌Cerebrospinal fluid absorption disorders
such as fetal meningitis and cerebrospinal fluid absorption disorders occur due to hydrocephalus
.
The classification
of hydrocephalus "Expert consensus on the diagnosis and treatment of idiopathic normal pressure hydrocephalus in China (2016 edition)" classifies hydrocephalus as follows : According to pathological classification:
obstructive hydrocephalus, communicating hydrocephalus, external hydrocephalus
.
Classified according to etiology: traumatic hydrocephalus, otogenic hydrocephalus, infectious hydrocephalus, mass hydrocephalus, hemorrhagic hydrocephalus
.
Classified according to the rate of onset: acute hydrocephalus, chronic hydrocephalus, normal pressure hydrocephalus, resting hydrocephalus
.
Classification by age: infantile hydrocephalus
, older children and adults.
Clinical manifestations of normal pressure hydrocephalus Typical clinical manifestations
of normal pressure hydrocephalus are gait disturbance, cognitive impairment, and urinary incontinence
。 Among them, gait disorders are the most common, cognitive impairment and urinary incontinence also occur to varying degrees, and about half of patients have triad at the same time
.
Gait disorders: gait disorders are often manifested as slow walking, unstable rocking, small stride distance, widening of foot spacing, smaller foot height, starting and turning obstacles, but normal
arm swing function when walking.
In the early stages of the disease, gait disturbances are mild and imperceptible, often complaining
of "dizziness".
As the disease progresses, typical gait disturbances manifest gradually
.
In advanced disease, patients need assistance to walk, or even not at
all.
Some patients have clinical manifestations similar to parkinsonism.
Cognitive impairment: Cognitive impairment of normal stress hydrocephalus is part of neuropsychological impairment and involves cognitive, emotional, and psychobehavioral aspects
.
Clinical manifestations are psychomotor retardation, apathy, emotional apathy, attention, memory, calculation, visuospatial function and executive dysfunction, etc.
, patients lack initiative and active communication ability, the above conditions may fluctuate, or short-term aggravation
.
Patients with reduced ability to perform daily living are one of the common types of dementia in clinical practice, and such patients have the possibility of recovery of cognitive dysfunction, so it is called reversible dementia
.
Urinary incontinence: bladder dysfunction of normal pressure hydrocephalus is neurogenic and accompanied by detrusor hyperactivity, which can be seen in the vast majority of patients with
normal pressure hydrocephalus.
Urinary frequency and urgency can occur early in the disease, and as the disease progresses, complete urinary incontinence may occur, even fecal incontinence, and urinary retention
may occur.
Diagnostic criteria
for normal pressure hydrocephalus are clinical findings and imaging findings that are necessary for the diagnosis of normal pressure hydrocephalus
.
However, given the complexity of diagnosing normal pressure hydrocephalus, there are three diagnostic levels of normal pressure hydrocephalus: clinically suspected, clinically diagnosed, and clinically confirmed
.
■ Clinically suspicious: (1) Adults have a slow onset and gradual worsening, and symptoms can fluctuate to aggravate or resolve; clinically present with at least 1 symptom of the triad of typical gait impairment, cognitive dysfunction, and urinary incontinence;
(2) Imaging shows ventricular enlargement, Evan's index > 0.
3, and no other causes of ventricular enlargement;
there may be (or) no low density around the ventricle (CT) or hyperintensity (T2-weighted image on MRI);
Coronal imaging shows signs of "subarachnoid incuncanes";
(3) Lumbar puncture (lateral decubitus position) or intracranial pressure monitoring in the ventricle confirmed that intracranial pressure ≤ 200mmH2O, and cerebrospinal fluid routine and biochemical examination were normal;
(4) Clinical, imaging and biochemical examinations exclude the existence of
other neurological and non-nervous system diseases that may cause the above clinical manifestations.
■ Clinical diagnosis: (1) Meet the diagnostic criteria for clinical suspicion of normal pressure hydrocephalus;
(2) Those who meet one of the following criteria at the same time:
(1) Symptoms improve after cerebrospinal fluid drainage test;
(2) Symptoms improved
after continuous cerebrospinal fluid drainage test.
■Clinical diagnosis:
Patients with clinical suspicion or clinical diagnosis, patients whose efficacy has improved significantly after surgical intervention of cerebrospinal fluid shunt surgery are confirmed
.
Differentiation
of normal pressure hydrocephalus and key points of normal pressure hydrocephalus and Alzheimer's disease:
Table 1 Identification points (as </b20 <b21>>Original)
Evaluation
of normal pressure hydrocephalus ■ Gait disorder evaluation:
(1) 10m walking test: according to the state of daily walking or auxiliary state, the time and number of
steps required for 10m straight line walking are measured.
After the drainage test, if one parameter is improved by more than 20%, or if both parameters are improved by more than 10%, it is positive
.
(2) 5m switchback walking test: measure the time and number of
steps required to stand up from the chair, walk in a straight line for 5m, and then return to sit.
After cerebrospinal fluid drainage or surgery, the regression walking test improves by more than 10% to be positive
.
In addition, it is difficult to close the eyes before releasing the liquid, or strengthen the test and evaluation
of closing the eyes and walking in a row.
■Cognitive impairment assessment:
MMSE or MoCA is recommended for cognitive dysfunction screening
。 This method is relatively rough, it is recommended to conduct connection test, number symbol, listening word memory test and jack test, and it is recommended to carry out emotional behavior evaluation and daily living ability evaluation to establish a comprehensive cognitive function evaluation, which is helpful to determine the degree of
cognitive function improvement.
An increase in MMSE score of more than 3 points is a positive result
.
■Voiding dysfunction: Voiding dysfunction questionnaire:
Patients and caregivers can be asked
about the questionnaire and scored according to the severity and frequency of occurrence.
■Overall Living Capacity Assessment:
Daily Living Abilities (ADL) is recommended Assessed
on scales and modified stroke quality of life rating scales.
Surgical treatment of normal pressure hydrocephalus At present, it has been confirmed that surgical treatment is an effective treatment
measure for normal pressure hydrocephalus, and various shunt surgeries, especially ventriculoperitoneal shunting, are the most common.
Early surgery can significantly improve the patient's condition and prognosis
.
Indications: Once the diagnosis of normal pressure hydrocephalus is made, it can be treated with surgery as soon as possible
after full evaluation and clinical diagnosis.
Contraindications: severe underlying diseases that cannot tolerate surgery, coagulation dysfunction that cannot be clinically corrected, intracranial infection, shunt channel infection, abdominal infection, etc
.
Surgical methods: mainly include: ventriculoperitoneal shunt, ventricular atrial shunt, lumbar pool abdominal shunt, etc
.
Ventriculoperitoneal shunting is the main operation
.
Figure 3 (from literature [1]) Meta-analysis
of the Japanese Society of Neurosurgery [4].
It was noted that symptom improvement in patients with normal pressure hydrocephalus ranged from 31% to 2 years after shunt surgery, and 61% to 91% improved symptoms in patients with follow-up for 3 to 5 years
.
Among them, the improvement rate of gait instability reached 58%-90%, the improvement rate of cognitive dysfunction was 29%-80%, and the improvement rate of urinary incontinence was 20%-78%.
US guidelines for idiopathic normal pressure hydrocephalus [5] indicate that symptoms such as dementia, gait instability, and urinary incontinence can be significantly improved
in 72% to 80% of patients after shunting.
It is clinically difficult to determine the course of normal pressure hydrocephalus due to comorbidities, but patients with normal pressure hydrocephalus who do not receive treatment tend to progress rapidly
.
In short, the symptoms of dementia and urinary incontinence often caused by normal intracranial pressure hydrocephalus are very similar to Alzheimer's disease, and many people are easily confused
.
Alzheimer's disease is an irreversible Alzheimer's disease, and normal pressure hydrocephalus can be treated surgically, and CT is repeated after 3 months, and if symptoms do not improve and the ventricles are still enlarged, a lower pressure shunt can be considered
.
After treatment, the patient's quality of life will also be significantly improved, and cognitive function will gradually improve
.
In general, the earlier the diagnosis, the greater
the chances of successful treatment.
References:
[1] Zhang Hongdian (main translation), Essentials of Neurosurgery.
Tianjin Publishing and Media Group.
October 2022, 1st Edition.
[2] Sun Zhenxiao, Yu Xiangfen.
Normal stress hydrocephalus with mental disorder as the first symptom: 1 case.
Journal of Clinical Psychiatry.
2017,27(03).
[3] Shang Jiaju, Yu Tao.
A case of acupuncture rehabilitation after normal pressure hydrocephalus flow surgery was reported.
Hunan Journal of Traditional Chinese Medicine.
2016,32(10).
[4] Madoka N，Shigeki Y，Masakazu M.
Guidelines for Management of Idiopathic Normal Pressure Hydrocephalus（Third Edition）：Endorsed by the Japanese Society of Normal Pressure Hydrocephalus.
Neurol Med Chir（Tokyo），2021.
61（2）：63-97.
[5] Abstracts of Presentations at the Association of Clinical Scientists 143rd Meeting Louisville，KY May 11-14，2022.
Ann Clin Lab Sci.
.
2022.
52（3）：511-525.
Where to see more Alzheimer's knowledge?
Come to the "Doctor Station" and take a look 👇
