Estimate your stroke recovery prognosis with the NIH Stroke Scale
Usually, doctors cannot tell you the exact stroke recovery prognosis because every stroke is different.
This means that every recovery and prognosis will also be different for each patient.
Luckily, there’s a way to estimate the impact and prognosis for your stroke using the NIH Stroke Scale (National Institutes of Health Stroke Scale).
It helps determine the impact of stroke by assessing your stroke side effects.
Before we dive into the stroke scale, let’s quickly address what a stroke is:
What Is a Stroke?
A stroke occurs when the supply of blood in the brain is compromised by a clogged artery (ischemic stroke) or a burst artery (hemorrhagic stroke).
The area where the stroke occurred will become damaged due to the lack of oxygen, causing various stroke side effects.
The location of the stroke will have a large impact on recovery. Here are some guides for your stroke location:
Determining Your Stroke Recovery Prognosis Using the NIH Stroke Scale
As soon as possible after stroke, a medical professional will assess the impact of the stroke using the NIH Stroke Scale.
The NIH Stroke Scale is a neurologic assessment that determines the severity of a stroke.
It assesses your bodily functions to determine how much and which part of the brain was damaged and the likelihood of recovery.
The areas of assessment are:
1. Level of consciousness
This evaluates the level of alertness and responsiveness of the stroke patient.
- A mild stroke may leave a patient totally responsive
- A severe stroke may leave a patient totally unresponsive
2. Horizontal extraocular movements
This assesses how well a patient can move their eyes horizontally.
- A mild stroke may not affect eye movement
- A moderate stroke may affect peripheral or central vision
- A severe stroke may result in the gaze being fixed to one side
3. Visual fields
This tests a patient’s ability to see what’s not directly in front of them (peripheral vision). Each eye is tested separately.
- A mild stroke may result in no vision loss
- A severe stroke may result in blindness in one eye
4. Facial palsy
Facial palsy is partial or complete paralysis of portions of the face. Symmetry is inspected while patients make various facial expressions.
(One of the indicators that someone is having a stroke is that half their face begins to droop.)
- A mild stroke may leave a patient with normal, symmetric movement
- A severe stroke may leave a patient with total paralysis on one side of the face
5. Motor Arm
This tests a patient’s ability to hold their arm up (at a 90 or 45 degree angle) for a certain amount of time.
- A mild stroke may result in slight arm drift where the arm slowly starts to drift down
- A severe stroke may result in total arm paralysis
6. Motor Leg
The leg is also tested for mobility by asking the patient to lift their leg and keep it lifted for a certain amount of time.
- A mild stroke may result in slight leg drift where the leg begins to drift downward
- A severe stroke may result in total leg paralysis
7. Limb Ataxia
Ataxia refers to the loss of bodily movement and control. It manifests as rigid or inaccurate movement.
All four limbs are assessed for ataxia to see if there was damage to the cerebellum, which is the motor center of the brain.
- A mild stroke may result in mild ataxia in one limb
- A severe stroke may result in ataxia in 2+ limbs
A sensory test is performed using pinpricks on all 4 limbs.
This tests a patient’s ability to feel sensation.
- A mild stroke may result in no sensory loss
- A moderate stroke may result in a difference in sensation on the affected side
- A severe stroke may result in total sensory loss on one side of the body
This assesses a patient’s language skills.
If language is affected by stroke, it can result in a stroke side effect called aphasia.
- A mild stroke may result in no speech impairment
- A moderate stroke may result in slight aphasia
- A severe stroke may result in severe aphasia
This measures the amount of dysarthria in a patient. Dysarthria is the lack of motor skills required to talk. It is purely a motor problem, not a language problem.
- A mild stroke may leave a patient with normal, clear speech
- A moderate stroke may leave a patient with some slurring of the speech
- A severe stroke may leave a patient with intense slurring of speech that makes it hard to understand
11. Extinction and Inattention
This part of the NIHSS further assesses a patients’ visual, tactile (touch/feeling), auditory, spatial, or personal attention.
While tactile and auditory abilities have already been assessed, this section allows the practitioner to assess a patient’s spatial awareness (i.e. awareness of their body and environment).
We will discuss this in greater detail later.
- A mild stroke may result in no extinction or inattention
- A severe stroke may result in lack of attention on one side of the body (one-sided neglect) or both sides of the body
How Your Stroke Recovery Prognosis Is Assessed
Based on these factors, patients are given a score between 0-4 for each test. All scores are then added up and used to determine the severity of the stroke as follows:
- 0 = no stroke symptoms
- 1-4 = minor stroke
- 5-15 = moderate stroke
- 16-20 = moderate to severe stroke
- 21-42 = severe (or “massive”) stroke
You can use this NIHSS calculator to get your score and stroke recovery prognosis.
Stroke Prognosis More Accurate for Left Hemisphere Strokes
The NIHSS has a particular focus on language and speech, which are left-brain tasks.
This implies that the NIHSS is more accurate for predicting outcomes of left-brain strokes.
One study showed the the NIHSS inaccurately predicts outcomes for upper extremity.
This implies that the NIHSS is less accurate for assessing upper extremity outcomes.
Now, Let’s Start Working on Healing These Side Effects
The NIH Stroke Scale gave you a good idea of how stroke side effects are measured.
But you may still be wondering how to treat these side effects.
So we’ll end this article with some useful guides for stroke recovery:
- Stroke recovery timeline: how long will recovery take?
- Best stroke treatment options
- How to recover from stroke