Brain

 The brain is the most complex part of the human body.

 The organ inside the head that controls all body functions of a human being.
 Made up of billions of nerve cells/neurons.
 The cranium protects the brain from injury.

Architecture of brain
The brain is composed of the cerebrum, cerebellum, and brainstem.

Cerebrum:
 It is the largest & front part of the brain.
 The cerebrum initiates and coordinates movement and regulates temperature.
 The cerebrum enable speech, judgment, thinking and reasoning, problem-solving, emotions and
learning.
 It relate to vision, hearing, touch and other senses.

Cerebellum:
 The portion of the brain in the back of the head between the cerebrum and the brain stem.
 Its function is to coordinate muscle movements, maintain posture, and balance.
 The cerebellum accounts for approximately 10% of the brain’s volume.( which is Latin for “little
brain”).
Brainstem:
 The brainstem is the structure that connects the cerebrum of the brain to the spinal cord and
cerebellum.
 Brainstem sends signals from brain to the rest of your body.
 Brain as CPU
Brain Vs CPU
Sl.No. Brain CPU
1 Biological Neurons or Nerve Cells Silicon Transistors
2 Neuron Size (10-6 m) Transistor Size (10-9 m)
3 200 billion neuron and 32 trillion 1 billion bite RAM, Trillion
interconnections of bytes of Disk.
4 Energy Consumption 6-10 Joules per operation Energy Consumption:10-16
per second Joules per operation per
second.
5 Learning Capacity Programmable Capacity
6 Input Tools: Human Sensory Organ Input tools: Keyboard,
Mouse, Touch Screen etc
7 Information Storage: Electrochemical & Information Storage: Bits
Electrical Signals.
8 High IQ No IQ

Nervous System:
 The nervous system is the highly complex network of an animal.
 It body’s command center.
 Nervous system transmits signals between the brain and the rest of the body.
 It processes sensory information from outside / inside the body and controls all behaviors
 It is divided into two parts (a) Central nervous system & (b) Peripheral nervous system.
 The basic building block of the nervous system is a nerve cell or neurons.
 Role:
 The Nervous system controls the movement.
 It controls the emotions.
 It controls sleeping, healing & aging.
 It controls the Digestion, breathing & heartbeat.
 It controls secretion of hormones & body temperature.
 It controls intelligence, memory, personality, sleeping and speech.
 It controls the response according to situation.
Note: Plants do not have a nervous system. They coordinate their behavior against environmental
changes with the help of Hormones.
Central nervous system(CNS): it is a part of nervous system consisting of brain and spinal
cord.
Reason for being referred to as CNS:
 The brain and spinal cord integrate the information received from the external environment via
the sensory nerves.
 They also coordinate the activities of the whole body of an organism by conducting motor
information to the effectors organs via the motor neurons.
 Hence, the brain and the spinal cord are called the central nervous system as they integrate
information got from the sensory receptors and coordinate activities of the organism through the
motor nerves.

Role of CNS
 sensory input.
 information processing.
 Memory and learning
 motor output. ( Brain has processed the information, impulses are then conducted from the brain
and spinal cord to muscles and glands, which is called motor output).

Architecture of the nervous system

 The nervous system can be divided into two parts.
 The central nervous system (CNS) includes the brain and spinal cord, working as an integrated
unit.
 Peripheral nervous system connect to the CNS via the spinal cord.
 Brain covered with shell of bone (the skull) and three layers of tough membranes.
 Cerebrospinal fluid that acts as a shock. that surrounds the brain and spinal cord of all
vertebrates.

.
 Peripheral nervous system (PNS): PNS is that part of your nervous system that lies outside the
brain and spinal cord. It consists all the nerves out side the brain and spinal card.
It is further divided into (a) Autonomic nervous system (ANS) & Somatic nervous system
(SNS):

(a) Autonomic nervous system: It is a part of peripherial nervous system, that control
unconscious processes( Sleep/Coma) of the body such as
 Blood pressure
 Heart and breathing rates
 Body temperature
 Digestion
 Metabolism
 The balance of water and electrolytes (such as sodium and calcium)
 The production of body fluids (saliva, sweat, and tears)
 Urination
 Defecation
 Sexual response.
 It is subdivided into (a) Parasympathetic nervous system & (b) Sympathetic nervous system.
( a) Parasympathetic nervous system: This can include control of your heart rate, blood
pressure, digestion, urination and sweating. It is responsible for the body's relaxation response.
(b) Sympathetic nervous system:
The sympathetic nervous system prepares the body for the “fight or flight” response during any
potential danger.
 It increases heart beat,
 Sweat increases
 Dilated (expand) mussels.
 Dilated of Pupils.
 Increased alertness.
Somatic Nervous system:
 They also carry commands from your brain to your muscles.
 Voluntary control of body movements via skeletal muscles.
 It also feeds information of senses — smell, sound, taste and touch.
Signal Transmission:
How nervous system transfer the information (Signal Transmission)

 Brain send the signals transmission through nervous system.

 The nervous system s is made of neurons, it send signal transmission through neurons.
 Dendrites: are tree-like structures that extend away from the cell body to receive incoming
information (neurotransmitters) from other neurons. The dendrites receive electrical impulses in
the form of chemical signals through the synapse(Synapse is the junction between two neurons
 A synapse is made up of a presynaptic and postsynaptic terminal.
 The presynaptic terminal is at the end of an axon and is the place where the electrical signal (the
action potential) is converted into a chemical signal (neurotransmitter release).
 The postsynaptic terminal receive the neurotransmitter signal released from the presynaptic
terminal and transduce it into electrical Signals.
 Note: This information, acquired at the end of the dendritic tip of a nerve cell sets off a chemical
reaction that creates an electrical impulse. This impulse travels from the dendrite to the cell
body, and then along the axon to its end. At the end of the axon, the electrical impulse sets off
the release of some chemicals. These chemicals cross the gap, or synapse, and start a similar
electrical impulse in a dendrite of the next neuron. This is a general scheme of how nervous
impulses travel in the body.
 These signals are converted to electrical signals in the dendrites. A nerve impulse is transferred
through a neuron in the form of electrical signals from the dendrites to the axonal end or the
axonal terminal of the neuron.

Electroencephalogram (EEG):
.
Definition: It is a medical test used to measure the electrical activity of the brain. A number of
electrodes are applied to your scalp. EEG can help diagnose a number of conditions including
epilepsy, sleep disorders and brain tumors. It can help detect potential problems with brain cell
communication
Preparation
 The patient head should be free from hair, oils, sprays, and conditioner.
 The patient should not take caffeine products up to 8 hours before the test.
 Patient lie in a comfortable bed.
 A technician places about 23 electrodes on scalp with glue or paste.
 Patient relaxes with either open or closed eyes.
 Patient may look at a bright light or breathe differently to see if brain has changes during these
activation procedures.
 The technologist will note the activity in the record.
Working/Principles
 The billions of cells in brain produce very small electrical signals that form non-linear patterns
called brainwaves.
 23 electrodes( sensors) are placed on scalp; electrodes pick up and record the electrical activity
in the brain.
 EEG sensors can record up to several thousands of snapshots of the electrical activity generated
in the brain within a single second.
 The recorded brainwaves are sent to amplifiers, and appear as a graph on a computer screen.
 It measures electrical activity in the brain.
 The electrodes detect tiny electrical charges that result from the activity of your brain cells.
 Applications: EEG might also be helpful for diagnosing or treating the following disorders
 Brain damage from head injury.
 Stroke.
 Sleep disorders.
 Brain tumor.
 EEG is the diagnostic procedure to confirm epilepsy.
 EEG during brain surgery or to test the brain activity of someone in a coma.
 Brain dysfunction.
 Confusion
 Memory Loss.
 Fainting
 GLUT1 deficiency syndrome.
 Inflammation of the brain (encephalitis).
Types of EEG
 Routine EEG: Routine EEG scans take 23 minutes.
 Prolonged EEG: A prolonged EEG test usually takes one hour and 15 minutes, but some types
can last several days.
 Ambulatory EEG: Ambulatory EEGs last one to three days.
 Sleep EEG: A technician performs an EEG test while you sleep.
 A prosthesis is a device designed to replace a missing part of the body or to make a part of the
body work better.
 These limbs are usually designed according to the individual’s appearance and functional needs.
 It will boost the confidence level.
 Robotic arms are the advanced prosthetic devices that use robotics technology to restore
functionality to individuals with upper limb amputations.
 These devices typically use motors, actuators, and sensors to mimic the movements of a human
arm and hand.
 Myoelectric control of a robotic arm prosthetic involves using the electrical signals generated
by the wearer's remaining muscles to control the movement of the prosthetic. The system
typically involves electrodes placed on the skin over the remaining muscle that are used to
detect and interpret the electrical signals generated by the muscle contractions.
 Brain-machine interfaces (BMIs) are a type of technology that allows a user to control a robotic
arm prosthetic directly with their brain activity. The system typically involves electrodes placed
on the scalp or implanted directly into the brain to detect and interpret the user's brain signals.

Robotic arms for prosthesis:

 Programmable mechanical arm with similar functions to a human arm is called robotic arms.
 Prosrobotic arm which works on slightly movement of muscles for disabled persons to fulfill the
duty to assist in the daily activities likes playing chess with friends, drinking etc.,
 These prosthetics have the shape of a human hand.
 It can be attached to the bone joints and have the same functions as real arms.
Advantages:
 It strength their self confidence.
 It enhances the mobility.
 It makes individual independent.
 The hand will improve the quality of life.
 It is suitable for most ages.
 Durable with minimum technical errors.
Parkinson Disease:
 Parkinson's disease is a brain disorder that causes unintended or uncontrollable movements, such
as shaking, stiffness, difficulty with balance and coordination.
 Parkinson's disease is caused by a loss of nerve cells in the part of the brain.
 Parkinson's diagnosis is based on your medical history, a review of patients symptoms,
neurological and physical exam.
 Parkinson's disease does not directly cause people to die.
 There is no cure for Parkinson’s disease.
 Treatments are available to help relieve the symptoms and maintain the quality of life.

Engineering solutions for Parkinson disease.

 Deep brain stimulation (DBS): Implanting electrodes in the brain to regulate abnormal neural
impulses, has improved the lives of countless people with Parkinson’s disease.
 Parkinson mPower app: Developed by University of Rochester. It contains the iPhone’s
sensors to measure patients’ tremor, balance, and gait to track and store this information via
specially designed activities. To download, visit Parkinsonmpower.org.
 Sleepio: A sleep app People living with Parkinson's may experience sleep problems. Sleepio is
a CBT (Cognitive Behavioural Therapy) app that aims to help user conquer long-term sleep
problems.
 Breathe2Relax(stress management tool): Breathing exercises can decrease the body’s ‘fight-
or-flight’ (stress) response and help with mood stabilization, anger control and anxiety
management.
 Cove (Music for mental health): Clinician-approved app that helps the induvisual to express
how you feeling using the power of music.
 Deep Brain Stimulation (DBS): DBS involves the implantation of electrodes into specific
regions of the brain to deliver electrical stimulation, which can help to relieve symptoms such
as tremors, stiffness, and difficulty with movement.
 Exoskeletons: Exoskeletons are wearable devices that provide support and assistance for
individuals with mobility issues. Some exoskeletons have been developed specifically for
people with Parkinson's disease, and can help to improve balance, reduce tremors, and increase
overall mobility.
 Rehabilitation: Rehabilitation involves the use of telecommunication technology to provide
physical therapy and rehabilitation services to individuals with Parkinson's disease, without the
need for in-person visits to a therapist.
 Smartwatch Applications: Smartwatch applications can be used to monitor symptoms of
Parkinson's disease, such as tremors, and provide reminders and prompts for medication and
exercise.
 Virtual Reality: Virtual reality systems can be used for rehabilitation and therapy for
individuals with Parkinson's disease, providing interactive and engaging environments for
patients to practice movements and improve coordination and balance.

Eye
 Eyes are the most valuable organ of the human body.
 The eyes interpret size, shape, colour and distance of the objects and give a 3D picture of the
objects visible.
 Eyes are organs of the visual system.
 The eye can be considered as a living optical device.
 A human eye is roughly 2.3 cm in diameter.

Architecture

The eye is the specialized organ

 Orbit:

 It is a bone cavity(socket) in the skull, that house for eye and it accessories
 The orbit which protects the eye from mechanical injuries, supports, and maximizes the function
of the eye.
 It is a quadrilateral pyramid shape.

Eyelid:

 Eyelid is a foldable skin that closes over the eye. There are upper and lower eyelids
 The eyelid protects the front part of the eye. The lid helps keep the eye clean and moist by
opening and shutting several times a minute. This is called blinking.
 It cover the eyes during sleeping and prevent evaporation.
The pupil
 The pupil is a black hole located in the center of the iris of the eye
 It regulates the flow of light to the retina.
  The pupil reacts to external light and changes its size accordingly. The pupil becomes larger in
dark and smaller in light.
 In bright light, the pupil constricts to protect the sensitive retina from damage.
Iris
 It is the colour part of the eye that contains the pupil in the center.
 The colored tissue at the front of the eye.
 It has muscles that control the size of the pupil and the amount of light that reaches the retina.
Lens
 The lens is a curved structure in the eye.
 It transmit light to focusing it on the retina.
 It is a transparent biconvex structure.
 It is a single lens.

After it travels through the pupil, light reaches the lens. This is a transparent, convex structure.
The lens can change shape, helping the eye focus light accurately onto the retina. With age, the
lens becomes stiffer and less flexible, making focusing more difficult.
Ciliary muscle
 This is a muscular ring attached to the lens.
 It contracts or relaxes to changes the shape of the lens.
 This process is called accommodation.
Cornea
 The cornea is the transparent front part of the eye that covers the iris, pupil etc,
 It acts as a structural barrier and protects the eye against infections.
 It contributing to the refractive power of the eye and focusing light rays on the retina with
minimum scatter and optical degradation. It is the eye’s first defense against foreign objects and
injury.
 Tt has no blood vessels.
 The cornea is densely populated with nerve endings and is highly sensitive
Vitreous and aqueous fluid
 Two fluids circulate throughout the eyes to provide structure and nutrients. Vitreous fluid is thick
and gel-like and is present in the back of the eye. It makes up most of the eye’s mass.
The retina
The retina is a layer of photoreceptors cells and glial cells within the eye that captures incoming
photons and transmits them along neuronal pathways as both electrical and chemical signals for
the brain to perceive a visual picture. Photoreceptor cells in the retina contain protein molecules
called opsins that are sensitive to light.The two primary photoreceptor cells are called “rods” and
“cones.” When these sense light, they send electrical signals to the brain.
Eye as a Camera System:
The human eye can be analogized to a camera system, as both the eye and a camera capture light
and convert it in to an image.
The main component soft eye that correspond to a camera system include:
 The Cornea: This transparent outer layer of the eye functions like a camera lens, bending light
to focus it on to the retina.
 The Iris: There is functions like the diaphragmina camera, controlling the amount of light that
enters the eye.
 The Pupil: The pupil functions like the aperture in a camera, adjusting the size to control the
amount to flight entering the eye.
 The Retina: The retina functions like the camera film or sensor, capturing the light and
 converting it in to electrical signals that are sent to the brain Rods.
 The Optic Nerve: The optic nerve functions like the cable connecting the camera to a
computer, transmitting the electrical signals from the retina to the brain.
Rod:
 They are in cylindrical in shape.
 Rods are a type of photoreceptor cell in the retina.
 Rods are more sensitive than the cones.
 Rod cells are highly sensitive to light and function in night vision.
 Rods are not sensitive to color.
 Rods are more in number (i.e., 120 millions) than cones.
 They containa protein called rhodopsin
 Cones:
 Cones are conical shaped cell.
 Cones are capable of detecting a wide spectrum of light photons and are responsible for colour
vision.
 The human eye only has about 6 million cones.
 Cones are present in central part of the retina.
Optic nerve
 The optic nerve is a thick bundle of nerve fibers that transmits signals from the retina to the
brain.
 Thin retinal fibers called ganglion cells carry light information from the retina to the brain.
 The ganglion cells leave the eye at a point called the optic disc.
 Because there are no rods or cones here, it is also called the “blind spot.”
The brain
 The brain gives depth perception by coordinating the signals from both eyes.
 The signals generated by the retina end up in the visual cortex, a part of the brain that processes
visual information. The visual cortex brings together impulses from both eyes to create images.
Optical Correction:
 Methods used to improve blurred vision caused by refractive error.
 The most common methods of vision correction are wearing eyeglasses or contact lenses.
 Two of the most common vision problems are myopia and hyperopia.
Nearsightedness (myopia):
 It is a common vision condition in which near objects appear clear, but objects farther away look
blurry.
 It is a very common vision disorder.
 It affects about one third of people.
 Myopia is corrected by using concave lenses of suitable focal length.
 It can produce an additional diversion in the light rays and the final image is formed on the
retina.
 A concave lens is called a diverging lens because the incident rays are bent outward.
 Farsightedness(hyperopia):
 It is a common vision condition in which you can see distant objects clearly, but objects nearby
may be blurry.
 Farsightedness is due to the eye not bending light properly.
 Hyperopic should be treated with glasses or cataract surgery.
 It is corrected by convex lens.
 It affects one by fourth of peoples.

Here are the different types of corrective surgeries,

 LASIK (laser in-situ keratomileusis)
 PRK (photorefractive keratectomy)
 RLE (refractive lens exchange).

Cataract:
 A condition in which the lens of the eye becomes cloudy.
 Most cataracts develop when aging or injury changes the tissue that makes up the eye's lens.
 Age is the most common cause of cataracts.
 Crystallins are the most prevalent proteins in the lens.
 Lens proteins denature and degrade over time.
 The denaturation of lens protein is accelerated by diseases such as diabetes mellitus &
hypertension.
 The denaturation of lens protein is accelerated Environmental factors such as toxins, radiation
and ultraviolet light.
Symptoms: Blurred, cloudy, dim vision, double vision, sensitivity to light, difficulty seeing at
night, headache.
 Cataract surgery removes your clouded lens and replaces it with a clear artificial lens called an
IOL.
 Reason for cataracts: Smoking, diabetics, heavy sunlight, steroid use, Injuries etc.,

Types of cataract:
Aged cataracts: It happen because of normal changes in the eyes as the person get older.
Traumatic cataracts: These cataracts form when something injures your eye.
Pediatric cataracts: Babies may be born with cataracts
Secondary cataracts: Secondary cataracts can develop within months or years after cataract
surgery is completed.
Cataract surgery:
 Cataract leads blindness. Surgery is only the alternate.
 The natural cloudy lens is removed and the artificial lens is implanted during the same surgery.
 It is one of the safest, effective & fastest methods.
 Surgery involves swapping out the cloudy lens with a new lens.
 The surgery is not doing simultaneously for both the eyes.

Snell's law gives the degree of refraction and relation between the angle of incidence, the
angle of refraction and refractive indices of a given pair of media.
 Due to the higher refractive index of water (1. 33) than air (1. 0003), the air bubble acts as a
diverging lens (Concave lens).
Lens material

An intraocular lens (or IOL) is a tiny, artificial lens for the eye. It replaces the eye's natural
lens that is removed during cataract surgery.
Artificial lenses are made of inert (or non-reactive) materials, such as PMMA, silicone, and
acrylic.
As like natural lens artificial lenses have refractive power or the ability to bend light, which
helps to focus light rays and images on the retina.
It is possible to correct nearsightedness and farsightedness with artificial lenses.
Monofocal Lenses
The monofocal lens only enables focus at just one distance – either near or distance.
Most patients who select monofocal lenses choose to have good distance vision and use reading
glasses to help with near visual tasks, such as reading, computer work, or sewing.
Multifocal Lenses
Multifocal lenses provide more than one type of focused, or clear, vision. They attempt to
provide clear vision both at distance and near simultaneously.
Because multifocal lenses correct both distance and reading vision, they can reduce the patient’s
dependence on eyeglasses and contact lenses.

Lens Material:
 Columbia Resin 39(CR-39):
 A plastic polymer commonly used in the manufacture of eyeglass lenses.
 It is light weight.
 I do not allow UV radiation (It is opaque to UV radiations).
 It has scratch resistance.
 It is resistance to most of the solvents & chemicals.
 Its index of refraction only slightly lower than that of crown glass.
 Plastic lenses tend to have a lower index of refraction, which require thicker lenses.
Polycarbonate (impact-resistant):
 These lenses are shatter-proof ( break into pieces) and provide 100% UV protection.
 These are durable lenses & provide an extra degree of safety for your eyes.
 Abrasion resistance is poor, but anti scratch coating will reduce slightly abrasion resistance.
 They are thinner & light weight.
Trivex:
 Trivex is a urethane-based pre-polymer.
 which are good optics, light weight and strength. Due do these properties, it is named as Trivex.
 It block (opaque) to UV light.
 It is the most light weight lens.
Bionic Eye:
 It is an device implanted into the human eye to restore functional vision in partial or total
blindness.
 The device typically consists of a camera, a processor, and an electrode array that is attached to
the retina. The camera captures images and sends signals to the processor, which then transmits
electrical stimulation to the electrodes in the retina to stimulate the remaining healthy cells and
restore vision. There stored vision is not perfect, but it can help people with vision loss to
perform daily tasks more easily and safely.
 The bionic eye is powered by a battery that is typically implanted behind the ear. The battery is
recharged through a device that is held near the eye, which transmits power wirelessly to the
battery. The device is typically rechargeable and can be used for several years before it needs to
be replaced.
Advantages:
 It helps to correct the vision.
 There is no surgical complications.
 Can be easily implanted
 No battery implanted within the body.
Disadvantages:
 Repairing is difficult if the device get damaged.
 Those who last vision due to other reason could not use the device.
 Electrical prosthesis is a surgically implanted into a human eye in order to allow for the
transduction of light in people who have sustained severe damage to the retina.
Retinal prosthesis
 A retinal prosthesis acts as artificial retina. It works to replace the function of photoreceptors
that have been lost during retinal degeneration.
Cortical prosthesis
 Some visual prostheses are not placed near the retina at all. These include devices that are
implanted on the optic nerve or parts of the brain such as the thalamus or the visual cortex
 Note: Retinitis pigmentosa (RP) is a group of rare eye diseases that affect the retina (the light-
sensitive layer of tissue in the back of the eye). RP makes cells in the retina break down slowly
over time, causing vision loss. RP is a genetic disease that people are born with. Symptoms
usually start in childhood, and most people eventually lose most of their sight.
 There’s no cure for RP. But vision aids and rehabilitation (training) programs can help people
with RP make the most of their vision.
Eye Brain
It is the living organism sight I is the device used to record images
Three dimension (3D) view is possible Two dimension view is possible.
The region covered is about 180 degree The region covered is about 60 dgree
Focal Length of the lens is fixed Focal length of the Lens can be Changed
The Pupil adjust the size while focusing Camera Lens move to change the fousing
 Architecture of Heart
 The heart is located in chest cavity (Thoracic cavity) between the two lungs.
 Heart has four chambers, two relatively small upper chambers called atria and two larger lower
chambers called ventricles.
 The ventricles are the chambers that pump blood and atrium are the chambers that receive blood.
 Right heart consists of right atrium and right ventricle. Left heart consists of left atrium and left
ventricle.
 The right and the left region of the heart are separated by a wall of muscle called the septum.
 The right atrium receive the deoxygenated blood from different parts of the body & pumps it to
the right ventricle. The right ventricle pumps the de-oxygenated blood to the lungs to pick up a
fresh supply of oxygen.
 The left atrium receives oxygenated blood from the lungs and pumps it to the left ventricle. The
left ventricle pumps the oxygen-rich blood to the body.
 Arteries carry oxygenated blood from heart to different parts of the body. Veins carry
deoxygenated blood from different parts of the body to heart.
 The pulmonary arteries carry blood from your heart to your lungs. The pulmonary artery is
located at the exit of the right ventricle & extending upwards. The right semilunar valves close
and prevent the blood from flowing back into the heart
 The aorta is the main vessel through which oxygen-rich blood travels from the heart to the rest of
the body. It also delivers nutrients and hormones.. The aorta begins at the left ventricle of the
heart & extending upward.
Note: The difference is that the word 'atrium' is the singular form of the structure and
'atria' is the plural form.
 The heart weighs between 7 and 15 ounces (200 to 425 grams)
 The human heart is about the size of a human fist
 Heart may have beat (expanded and contracted) more than 3.5 billion times at the end of long life
person.
 Each day, the average heart beats 100,000 times, pumping about 2,000 gallons (7,571 liters) of
blood.
 The upper chambers are called the left and right atria, and the lower chambers are called the left
and right ventricles.
 It has a normal pyramidal shape in adults.
Pacemaker:
 Pacemaker is a small battery operated device.
 A small incision (cut) is made. Most often, the cut is on the left side (patients are right handed)
of the chest below the collarbone.
 A pacemaker is implanted under the skin.
 This procedure takes about 1 hour in most cases. Patient will be given a sedative to help to relax
& will be awake during the procedure.
 A pacemaker is used to control or increase the heartbeat.
 A pacemaker only works when it senses trouble with the heartbeat.
 It stimulates the heart as needed to keep it beating regularly.
 Pacemakers send electrical signals to help the heart beat at a normal rate and rhythm.
 An electrical signal to the heart typically controls the heartbeat. Electrical signals are called
impulses, move through the heart chambers. This help the heart beat at a normal rate and rhythm.
 Pacemakers can also be used to help the heart chambers beat in sync, so heart can pump blood
more efficiently to different parts of the body.
When Pacemaker needed
 The patient have a slow or irregular heartbeat that lasts for a long time, also called chronic.
 The patient have heart failure.
There are three types of pacemakers.
 Single chamber pacemaker. A single-chamber pacemaker delivers electrical impulses to
either the right atrium or the right ventricle e of the heart to regulate its rhythm.
 Dual chamber pacemaker. A dual-chamber pacemaker delivers electrical impulses to both the
right atrium and the right ventricle of the heart tor egulate its rhythm.
 Biventricular pacemaker. This type also is called a cardiac resynchronization pacemaker.
Patient have heart failure and a slow heartbeat. The device stimulates both ventricle (lower heart
chambers). It helps make the heart muscle stronger.
 Newer pacemakers weigh as little as 1 ounce (28 grams). Most pacemakers have 3 parts:
 A pulse generator: Which contains the battery and generate electric signals to control the
heartbeat.
 Leads: Consists of one to three insulated wires these are connected to the pulse generator on
one end & other end placed inside the one or more heart's chambers. Leads transmit electrical
impulses from the pulse generators to the heart muscle to assist and support synchronized blood
flow to the rest of the body.
 An electrode on each lead: The electrode on the end of a lead and touches the heart wall. The
electrodes delivers the electrical impulses to the heart. It also senses the heart's electrical activity
and relays this information back to the pulse generator.
 Note: Artery supply oxygenated blood from heats to different parts of the body.
 veins carry blood towards the heart.
 Plaque:1. An semi-hardened accumulation of substances from fluids in artery.
 Sinoatrial (SA) node: The sinoatrial node (SAN) is the natural pacemaker of the heart that
determines heart rate in mammals
 An electrical stimulus is generated in a special part of the heart muscle called the sinusnode. It's
also called the sinoatrial node(SA node). Thesinus nodeisa small mass of special tissue in the
right upper chamber of the heart(right atrium). It Sends the signals that make heart beat.
 In an adult, the sinus node sends out a regular electrical pulse 60 to 100 times per minute. This
electrical pulse travels down throughthe conduction pathways and causes the heart's lower
chambers (ventricles) to contract and pumpoutblood.
 The right and left atria are stimulated first and contract to push blood from the atria in to the
ventricles. The ventricles then contract to push blood out in to the blood vessels of the body.
Reason for blockage Blood vessels.
 Blocked arteries is known as Atherosclerosis .
 It is the build-up of fibrous and fatty material inside the arteries.
 Arterial plaque occurs when cholesterol builds up in the inner lining of the artery.
 High cholesterol levels can increase the rate of plaque buildup.
 There is no easy way to unclog an artery once plaque has built up.
 Ischemia is a condition in which blood flow (and thus oxygen) is restricted or reduced in a part
of the body.
 Clogged peripheral arteries in the lower part of the body (peripheral artery disease or PAD) most
often cause pain and cramping in the legs.
Other Reason for blockage are
 Modern life style
 Junk food ( Unhealth diet)
 Physical inactivity
 Overweight
 unrelieved stress
 Smoking
 Diabetic

In addition to chest pain, symptoms of a clogged artery may include:

 Dizziness.
 Feeling like your heart is racing (heart palpitations)
 Nausea.
 Shortness of breath.
 Sweating.
 Weakness.
 Smoking
Stent: A stent is a small mesh tube inserted in the blocked area to allow the blood to flow. The
stent restores the flow of blood or other fluids.

Types of Coronary Stents

1. Bare metal stents (BMS)
2. Drug-eluting stents (DES)
3. Bioresorbable scaffold system (BRS)
4. Drug-eluting balloons (DEB
Procedure for stents insertion
It is called angioplasty.
 The stent, which is collapsed around a balloon at the tip of the catheter, is guided through the
artery to the blockage.
 At the blockage, the balloon is inflated and the spring-like stent expands and locks into place
inside the artery.
 The stent is left in place permanently to allow blood to flow more freely(more than one stent
may be needed to open a blockage).
 It is not considered as major surgery
 Advantages of stents include:
 They help blood flow better through the artery where they're placed.
 Along with angioplasty, they can stop a heart attack.
 They improve the symptoms, such as shortness of breath and chest pain (when yprovider places a
stent in your coronary artery).
Disadvantages
 In some patients, it leads to stent thrombosis.
Design of Stents
Shape: Stents can be designed in a variety of shapes, including cylindrical, helical, and spiraled
to match the shape of the blood vessel and provide adequate support.
Materials:
 The physical design of a wire mesh structure made from the nitinol alloy(Nitinol is typically
made from 55% nickel and 45% titanium.).
 Stainless steel: this is the most common material used for stents. Its advantages include good X-
ray visibility; a fairly elastic and resistant consistency; and good biocompatibility.
 Metal stents are made of bare metal or covered with another material such as silicone. Hybrid
stents contain a mixture of materials.
 Silicone stents are made of a material that can be molded to a certain shape. They are used
more often if the stent is temporary.
 Expansion mechanism: Stents can be designed to expand in different ways, such as by balloon
inflation or self-expansion, depending on the type of stent and the specific medical condition it
is used to treat.
 Overall, the design of stents plays an important role in their effectiveness and safety. Stents
must be designed to provide adequate support to the blood vessel, prevent restenosis, and
minimize the risk of complications such as blood clots.
 Stents range from 8 to 38 mm in length and from 2.5 to 4.0 mm in diameter.
 Coil stents are made of wires that are formed into a circular coil to form the stent scaffold, while
the slotted tube stents are constructed from a metallic tube and then laser etching is used to cut
out the design.
Electrocardiogram(ECG): Records the electrical signal from the heart to check for different
heart conditions.
 Uses: An electrocardiogram (ECG) is a simple, non-invasive test that records the electrical
activity of the heart. An ECG can help diagnose certain heart conditions, including abnormal
heart rhythms and coronary heart disease (heart attack and angina).
If the test is normal, it should show that your heart is beating at an even rate of 60 to 100 beats
per minute.
An ECG Can Recognize the Signs of Blocked Arteries. But for further accurecy a CT coronary
angiogram can reveal plaque buildup and identify blockages in the arteries, which can lead to a
heart attack
Working
 Small sticky dots (electrodes) and wire leads are placed on your chest, arms and legs.
 The leads attach to the ECG machine (electrocardiograph) which records the electrical activity of
the heart muscle and displays this as a trace on a screen or on paper.
 It involves attaching electrodes (small, skin-sticking plastic patches) to specific areas of the
chest, arms, and legs to record the electrical signals produced when your heart beats.
 These electrical signals are represented on an ECG as 12 leads depicting different sections of the
heart.
 The electrode picks up the current and transmit them to an amplifier inside the
electrocardiograph.
 Then electrocardiograph amplifies the current and records them on a paper as a wavy line.

Note:
Note: Coronary arteries supply blood to the heart muscle.
Coronary angioplasty is also performed as an emergency treatment during a heart attack.
During the procedure a small balloon is inserted to push the fatty tissue in the narrowed artery
outwards. This allows the blood to flow more easily.
Defibrillator: A defibrillator is a device that gives a high energy electric shock to the heart of
someone has cardiac arrest.
Defibrillators can help get a person out of sudden cardiac arrest by restoring their normal rhythm
so that they will start breathing again and blood flow starts up once more through the body's vital
organs.
 A defibrillator works by de-polarising the cardiac muscle with a short electrical shock. This
allows the cells in the heart to recharge at the same time, reestablishing the sinus rhythm in the
process.
A defibrillator can help you survive sudden cardiac arrest.

Types
 Manual external defibrillator
 Manual internal defibrillator
 Semi-automatic eternal defibrillator
 Automated external defibrillator (AED)
 Implantable cardioverter-defibrillator (ICD)
 Wearable cardiac defibrillator

cardiopulmonary resuscitation (CPR) provides temporary assistance, a defibrillator can help you
survive sudden cardiac arrest.
User annual
 Put two defibrillator paddles or sticky pads (connected to the defibrillator) on your chest.
 One paddle or pad goes below your right shoulder and the other below your left nipple.
 To prevent burns, conducting material is already in the pads. However, your provider will need
to put conducting material on your chest before using paddles.
 For sticky pads, push a button on the machine to give the shock. For handheld paddles, push the
button on each paddle at the same time.
 Step 1: Turn the defibrillator on by pressing the green button and follow its instructions.
 Step 2: Peel off the sticky pads and attach them to the patient’s skin, one on each side of the
chest, as shown in the picture on the defibrillator.
 Step 3: Once the pads have been attached, stop CPR and don’t touch the patient. The
defibrillator will then check the patient’s heart rhythm.
 Step 4: The defibrillator will decide whether a shock is needed and if so, it will tell you to press
the shock button. An automatic defibrillator will shock the patient without prompt. Don’t touch
the patient while they are being shocked.
 Step 5: The defibrillator will tell you when the shock has been delivered and whether you need
to continue CPR.
 Step 6: Continue with chest compressions until the patient shows signs of life or the defibrillator
tells you to stop so it can analyse the heartbeat again.
What is the difference between a defibrillator and a pacemaker?
A pacemaker is an implantable device that keeps a person’s heartbeat steady throughout their
daily activities with a very low dose of electricity. It helps the heart to speed up during physical
exertion or keep a heart going when the heart muscle is weakened from something like a heart
attack.
 A defibrillator, on the other hand, administers a stronger electrical pulse when it detects irregular
heart behavior. Instead of a regulator like a pacemaker, a defibrillator is an emergency response
device.

 Heart related issues / diseases:

 Arrhythmias: Abnormalities in the heart's rhythm or rate can be detected using an ECG.
 Heart disease: Changes in the heart's electrical activity can indicate the presence of heart
disease, such as coronary artery disease or heart attacks.
 Heart attack: An ECG can help diagnose a heart attack by detecting changes in the heart's
electrical activity that indicate a lack of blood flow to the heart.
 Heart enlargement :The term "cardiomegaly" refers to an enlarged heart seen on any imaging
test, including a chest X-ray.If the heart weakens, as it can with heart failure
 Genetic heart defects:
 Familial Hypertrophic Cardiomyopathy: Familial hypertrophic cardiomyopathy is a fairly
common inherited heart condition that can affect people of any age. This disease can thicken part
or all of the heart muscle. In extreme cases, it can even cause sudden death.
 Familial Dilated Cardiomyopathy: While hypertrophic cardiomyopathy causes the heart
muscle to thicken, the opposite is true of dilated cardiomyopathy: the heart muscle becomes thin
and weak.
 Familial hypercholesterolemia is an inherited cause of coronary heart disease. If it is untreated,
leads stroke or suffer from a heart attack.
Poor blood supply to heart:
Myocardial ischemia occurs when blood flow to the heart is reduced, preventing the heart
muscle from receiving enough oxygen. The reduced blood flow is usually the result of a partial
or complete blockage of your heart's arteries (coronary arteries).
Heart inflammation (myocarditis): Myocarditis occurs when the heart muscle becomes
inflamed. When your heart muscle is inflamed, it can affect the heart’s electrical system.

Questions.
Discuss the architecture of Brain.
Explain the role of Central nervous system in animals.
Explain the role of Peripheral nervous system.
Write a note on signal transition through nervous system.
Write a note on EEG or Explain the function & applications of EEG.