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6 Minute Walk Test
The 6 Minute Walk Test (6MWT) is a simple and widely used measure of functional exercise capacity. It is often employed in clinical settings to assess the distance an individual can walk within a span of six minutes. The test is typically conducted in a hallway of a standardized length, and the individual is instructed to cover as much ground as possible in the given time frame. Learn more about 6 minute walk test.
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Acute Respiratory Distress Syndrome (ARDS)
Acute Respiratory Distress Syndrome (ARDS) is a severe and potentially life-threatening lung condition characterized by rapid onset of widespread inflammation in the lungs. This inflammation leads to increased permeability of the tiny air sacs in the lungs, called alveoli, causing fluid to leak into the lungs’ airspaces. As a result, oxygen levels in the bloodstream drop, leading to respiratory failure and difficulty breathing. Learn more about Acute Respiratory Distress Syndrome (ARDS).
Alpha-1 antitrypsin (AAT)
Alpha-1 antitrypsin (AAT) deficiency is a genetic disorder characterized by low levels of a protein called alpha-1 antitrypsin (AAT) in the blood. AAT is produced by the liver and serves a crucial role in protecting tissues from damage caused by enzymes released by white blood cells, especially in the lungs and liver. Click here to learn more about Alpha-1 antitrypsin (AAT).
Asthma
Asthma is a condition in which your airways narrow and swell and may produce extra mucus. This can make breathing difficult and trigger coughing, a whistling sound (wheezing) when you breathe out and shortness of breath. Learn more about Asthma.
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Bronchoscopy
Bronchoscopy is a medical procedure that allows a healthcare provider to examine the airways and lungs using a thin, flexible tube called a bronchoscope. The bronchoscope is typically inserted through the nose or mouth and then advanced through the trachea (windpipe) into the bronchi and smaller airways of the lungs. Learn more about Bronchoscopy.
Bruxism
Bruxism is the involuntary grinding or clenching of teeth, often occurring during sleep (sleep bruxism) or while awake (awake bruxism). It can lead to a range of dental and health issues. Click here to learn more.
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COPD
COPD stands for Chronic Obstructive Pulmonary Disease. It is a progressive lung disease that makes it difficult to breathe and is often characterized by persistent respiratory symptoms such as coughing, wheezing, shortness of breath, and chest tightness. COPD encompasses two main conditions:
Chronic Bronchitis: This involves inflammation and narrowing of the airways (bronchi) leading to excessive mucus production, chronic cough, and difficulty clearing the airways.
Emphysema: This condition damages the air sacs (alveoli) in the lungs, reducing their elasticity and surface area, which impairs the exchange of oxygen and carbon dioxide.
Learn more about COPD.
COVID-19
The virus is thought to spread mainly from person-to-person. Between people who are in close contact with one another (within about 6 feet). Through respiratory droplets produced when an infected person coughs or sneezes. Learn more about COVID-19.
CPAP
CPAP stands for Continuous Positive Airway Pressure. It is a non-invasive treatment for sleep apnea, a sleep disorder characterized by pauses in breathing or shallow breaths during sleep. CPAP therapy involves the use of a CPAP machine, which delivers a continuous stream of pressurized air through a mask that covers the nose and/or mouth, helping to keep the airway open and prevent obstruction. Learn more about CPAP.
Central Sleep Apnea (CSA)
This type occurs when the brain fails to send proper signals to the muscles that control breathing. Unlike OSA, there’s no physical blockage of the airway in CSA; instead, the problem originates in the respiratory control center of the brain.
Circadian rhythm disorders
Circadian rhythm disorders are a group of sleep disorders characterized by a misalignment between an individual’s internal biological clock and the external environment, specifically the light-dark cycle. These disorders disrupt the normal sleep-wake cycle, leading to difficulty falling asleep, waking up at the desired times, or maintaining a consistent sleep pattern. Learn more about Circadian rhythm disorders
Complex/Mixed Sleep Apnea
This type is a combination of obstructive and central sleep apnea, where individuals may experience features of both conditions. Learn more about Complex/Mixed Sleep Apnea.
Confusional Arousals
Confusional arousals are a type of parasomnia, which is a disorder characterized by abnormal behaviors, movements, or experiences occurring during sleep. Learn more about Confusional Arousals.
Cough
A cough is a reflex action that helps clear the airways of irritants, mucus, or foreign particles. It is a common symptom of various respiratory conditions, infections, allergies, and environmental factors. Coughing is a protective mechanism designed to prevent substances from entering or obstructing the respiratory system and to expel substances that are already present in the airways. Learn more about Coughing.
Cystic Fibrosis (CF)
Cystic Fibrosis (CF) is a genetic disorder that primarily affects the lungs and digestive system. It is caused by mutations in the CFTR (Cystic Fibrosis Transmembrane Conductance Regulator) gene, which leads to the production of thick, sticky mucus in various organs, particularly the lungs and pancreas. Learn more about Cystic Fibrosis (CF)
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Delayed sleep phase syndrome
Delayed Sleep Phase Syndrome (DSPS) is a type of circadian rhythm disorder where an individual’s sleep-wake cycle is significantly delayed compared to the conventional sleep-wake schedule. This means that people with DSPS have difficulty falling asleep at a typical bedtime and consequently have trouble waking up at a desired or socially acceptable time. Click here to learn more about Delayed sleep phase syndrome.
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Emphysema
Emphysema is a type of chronic obstructive pulmonary disease (COPD) characterized by damage to the air sacs (alveoli) in the lungs. These air sacs gradually become weakened and stretched out, leading to permanent enlargement and loss of elasticity. This structural damage impairs the ability of the air sacs to effectively exchange oxygen and carbon dioxide during breathing. Learn more about Emphysema.
Excessive daytime sleepiness (EDS)
Excessive daytime sleepiness (EDS) refers to a condition where a person experiences persistent drowsiness and a strong urge to sleep during the day, even after having a full night’s sleep. This excessive sleepiness can interfere with daily activities, work, and social interactions, leading to impaired functioning and reduced quality of life. Learn more about Excessive daytime sleepiness (EDS).
Exploding Head Syndrome
Exploding head syndrome (EHS) is a type of parasomnia characterized by the perception of loud noises or a sensation of a sudden explosion in the head while falling asleep or waking up. Click here to learn more about Exploding Head Syndrome.
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Home Sleep Apnea Test (HSAT)
A Home Sleep Apnea Test (HSAT) is a diagnostic tool used to evaluate sleep-disordered breathing, particularly obstructive sleep apnea (OSA), from the comfort of a patient’s own home. This test is typically prescribed for individuals who are suspected of having sleep apnea but don’t require more complex monitoring in a sleep laboratory setting. Click here to learn more about Home Sleep Apnea Test (HSAT).
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Idiopathic hypersomnia
Idiopathic hypersomnia is a sleep disorder characterized by excessive daytime sleepiness despite getting a sufficient amount of sleep at night. Click here to learn more about Idiopathic hypersomnia.
In-lab Sleep Study
An in-lab sleep study, also known as polysomnography (PSG), is a diagnostic test conducted in a sleep center or laboratory to evaluate and monitor various physiological factors during sleep. It is often used to diagnose sleep disorders and assess the quality of sleep. During an in-lab sleep study, a patient stays overnight in a sleep clinic where their sleep patterns and related activities are monitored. Learn more about In-lab Sleep Study.
Influenza
Influenza, commonly known as the flu, is an infectious disease caused by influenza viruses. It primarily affects the respiratory system, including the nose, throat, and lungs. Symptoms of the flu typically include:

Fever
Cough
Sore throat
Runny or stuffy nose
Muscle or body aches
Headaches
Fatigue
Sometimes, gastrointestinal symptoms like nausea, vomiting, or diarrhea. Click here to learn more about Influenza.

Insomnia
Insomnia is a sleep disorder characterized by difficulty falling asleep, staying asleep, or both, despite having the opportunity and environment for sleep. It can lead to daytime fatigue, irritability, difficulty concentrating, and overall impaired functioning. Learn more about Insomnia.
Interstitial lung diseases (ILD)
Interstitial lung diseases (ILD) also called Diffused parenchymal lung diseases (DPLD) are a group of diseases which are characterized by bilateral, patchy pulmonary fibrosis. In these diseases mainly the alveoli, interstitial spaces, basement membrane, alveolar epithelium, interstitial vasculature, perivascular and perilymphatic tissues are affected. Damage to concerned sites lead to abnormal ventilation-perfusion ratio which further leads to hypoxia. In such conditions, the physicians conduct a chest radiograph to observe typical ground-glass shadows. The characteristic pathologic and histologic features categorize the diseases falling under ILD. If prompt measures are not taken the condition of patient can worsen causing scarring and gross destruction of lung. Respiratory failure, pulmonary hypertension and cor pulmonale are common complications. In end stage, the lung is called honey-comb due to its gross appearance. Learn more about Interstitial lung diseases (ILD).
Interstitial lung diseases (ILD)
Interstitial lung diseases (ILD) also called Diffused parenchymal lung diseases (DPLD) are a group of diseases which are characterized by bilateral, patchy pulmonary fibrosis. In these diseases mainly the alveoli, interstitial spaces, basement membrane, alveolar epithelium, interstitial vasculature, perivascular and perilymphatic tissues are affected. Damage to concerned sites lead to abnormal ventilation-perfusion ratio which further leads to hypoxia. In such conditions, the physicians conduct a chest radiograph to observe typical ground-glass shadows. The characteristic pathologic and histologic features categorize the diseases falling under ILD. If prompt measures are not taken the condition of patient can worsen causing scarring and gross destruction of lung. Respiratory failure, pulmonary hypertension and cor pulmonale are common complications. In end stage, the lung is called honey-comb due to its gross appearance. Learn more about Interstitial lung diseases (ILD).
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Lung Cancer
Lung cancer is one of the most aggressive cancers which is rapidly becoming the most fatal cancer worldwide. The occurrence of lung cancer is nearly equal in both men and women. It seems that lung cancer and breast cancer have quite tough competition to rank first in being lethal among women. There is strong evidence that tobacco smoking and other environmental carcinogens are responsible for driving mutations that result in transformation of benign progenitor cells in the lung into neoplastic cells possessing all hallmarks of cancer. Although quitting smoking lowers the risk of lung cancer yet the irreversible damage to the baseline and genetic changes favor the development of lung cancer. Passive smoking is also equally responsible for its development. Learn more about lung cancer.
Lung Cancer Screening
Lung cancer screening is typically done using a low-dose computed tomography (CT) scan. This imaging test allows healthcare providers to visualize the lungs and detect any abnormalities, such as nodules or tumors, at an early stage when treatment may be more effective. Click here to learn about lung cancer screening.
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Narcolepsy
Narcolepsy is a chronic neurological disorder that affects the brain’s ability to regulate sleep-wake cycles. People with narcolepsy experience excessive daytime sleepiness and may have sudden, uncontrollable episodes of falling asleep during the day. These episodes can occur at inappropriate times, such as during work or conversations, and can last from a few seconds to several minutes. Learn more about Narcolepsy.
Nightmare Disorders
Nightmare disorder, also known as dream anxiety disorder, is a condition characterized by recurrent nightmares that cause significant distress or impairment in daily functioning. Click here to learn more about nightmare disorders.
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Obstructive Sleep Apnea (OSA)
This is the most common type, where the throat muscles relax excessively during sleep, causing the airway to narrow or close completely. This leads to reduced airflow or complete blockage, resulting in disrupted breathing patterns. Learn more about Obstructive Sleep Apnea (OSA).
Occupational Lung Disease
Occupational lung diseases are conditions caused by inhaling certain substances in the workplace over a prolonged period. These substances can include dust, chemicals, fumes, and other airborne particles. Occupational lung diseases can vary widely in severity and presentation, depending on the type of exposure, duration of exposure, and individual susceptibility. Learn more about Occupational Lung Disease.
Oral Appliance Therapy
Oral appliance therapy (OAT) is a treatment option primarily used for sleep-related breathing disorders, particularly obstructive sleep apnea (OSA). This therapy involves the use of a custom-fitted dental device that you wear during sleep. The appliance helps to reposition the jaw and tongue to keep the airway open, reducing or preventing the airway blockages that characterize OSA. Click here to read more.
Overnight oximetry
Overnight oximetry is a medical test that measures the levels of oxygen in a person’s blood during the night while they sleep. It is commonly used to assess and monitor individuals with respiratory or sleep-related disorders, such as sleep apnea.
Oxygen Evaluation Test
Oxygen evaluation test could encompass various assessments aimed at evaluating oxygen levels in the blood or the body’s ability to absorb and transport oxygen. Learn more about Oxygen Evaluation Test.
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Pulmonary Embolism
A pulmonary embolism (PE) is a serious medical condition that occurs when a blood clot (usually originating in the veins of the legs or pelvis) travels to the lungs and blocks one of the pulmonary arteries or one of its branches. This blockage can reduce or completely cut off blood flow to a portion of the lung, leading to potentially life-threatening consequences. Learn more about Pulmonary Embolism.
Pulmonary Function Test (PFT) 
A pulmonary function test (PFT) is a series of non-invasive breathing tests that measure how well your lungs are functioning. Learn more about Pulmonary Function Test (PFT).
Pulmonary Hypertension (PH)
Pulmonary hypertension (PH) is a condition characterized by high blood pressure in the arteries of the lungs. This increased pressure in the pulmonary arteries can strain the heart and lead to various complications over time. Learn about Pulmonary Hypertension (PH).
Pulmonary fibrosis
Pulmonary fibrosis is a progressive lung disease characterized by the formation of scar tissue (fibrosis) in the lungs. This scar tissue thickens and stiffens the lung tissue, making it difficult for the lungs to function properly and efficiently exchange oxygen and carbon dioxide with the bloodstream. Learn about Pulmonary fibrosis.
Pulmonologist
A pulmonologist is a medical doctor who specializes in the field of pulmonology, which focuses on the respiratory system. Pulmonologists diagnose and treat conditions and diseases affecting the lungs and respiratory tract, such as asthma, chronic obstructive pulmonary disease (COPD), pneumonia, tuberculosis, lung cancer, and pulmonary hypertension. They are trained to perform procedures such as bronchoscopy, which involves examining the airways using a thin, flexible tube with a camera, and they may also interpret various pulmonary function tests to evaluate lung function. Pulmonologists often work closely with other healthcare professionals, including primary care physicians, respiratory therapists, and thoracic surgeons, to provide comprehensive care for patients with respiratory issues.
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REM Sleep Behavior Disorder (RBD)
REM Sleep Behavior Disorder (RBD) is a sleep disorder characterized by the acting out of dreams during the Rapid Eye Movement (REM) sleep stage. Normally, during REM sleep, the body experiences a temporary paralysis of the muscles (known as REM atonia) which prevents people from physically acting out their dreams. In RBD, this muscle paralysis is absent or incomplete, leading to potentially violent or dangerous behaviors during sleep. Click here to learn more about REM Sleep Behavior Disorder (RBD).
Restless Legs Syndrome (RLS)
Restless Legs Syndrome (RLS), also known as Willis-Ekbom Disease, is a neurological disorder characterized by uncomfortable sensations in the legs and an uncontrollable urge to move them. These sensations typically occur during periods of rest or inactivity, such as when sitting or lying down, and can disrupt sleep and daily activities. Learn more about Restless Legs Syndrome (RLS)
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Sarcoidosis
Sarcoidosis is a rare inflammatory disease that can affect multiple organs in the body, but it most commonly involves the lungs and lymph nodes. In sarcoidosis, small collections of inflammatory cells, called granulomas, form in various tissues and organs. These granulomas can affect the normal structure and function of the affected organs.

The exact cause of sarcoidosis is unknown, but it is believed to result from an abnormal immune response triggered by exposure to certain environmental factors in genetically susceptible individuals. Sarcoidosis can occur at any age and affects people of all races and ethnicities, but it is most commonly diagnosed in adults between the ages of 20 and 40. Learn more about Sarcoidosis.
Seasonal Allergies
Seasonal allergies, also known as allergic rhinitis or hay fever, are allergic reactions that occur at specific times of the year when certain outdoor allergens are most prevalent. These allergens typically include pollen from trees, grasses, and weeds, although mold spores can also contribute to seasonal allergy symptoms. Click here to learn more about seasonal allergies.
Shift Work Sleep Disorder
Shift Work Sleep Disorder (SWSD) is a condition that affects people who work non-traditional hours, such as night shifts or rotating shifts. It is characterized by difficulties in sleeping and staying awake due to the misalignment between the body’s internal circadian rhythm and the external work schedule. This misalignment can lead to significant sleep disturbances and related health problems. Click here to learn more about Shift Work Sleep Disorder.
Sleep Apnea
Sleep apnea is a sleep disorder characterized by pauses in breathing or shallow breaths during sleep. These pauses can last from a few seconds to minutes and can occur multiple times throughout the night. Learn more about Sleep Apnea.
Sleep Terrors
Sleep terrors, also known as night terrors, are a type of parasomnia, which are disruptive sleep disorders. They are characterized by sudden episodes of intense fear, screaming, and other physical or vocal manifestations that occur during the transition from deep non-REM sleep to lighter stages of sleep or wakefulness. Unlike nightmares, which occur during REM sleep and can be remembered upon waking, sleep terrors happen during non-REM sleep, typically in the first third of the night, and are often not remembered by the person experiencing them. Click here to learn more about sleep terrors.
Sleepwalking
Sleepwalking, also known as somnambulism, is a sleep disorder characterized by complex behaviors that occur during deep sleep, usually during the non-rapid eye movement (NREM) stages. These behaviors can range from simple actions like sitting up in bed to more complex activities like walking around the room or even leaving the house. Learn more about sleepwalking.
Snoring
Snoring is a common sleep-related phenomenon characterized by noisy breathing during sleep, typically caused by vibrations of the soft tissues in the upper airway. It is often considered a nuisance for both the person who snores and their sleep partners, as it can disrupt sleep quality and lead to daytime fatigue and irritability. Learn more about snoring.
Spirometry
Spirometry is a common pulmonary function test that measures the amount and speed of air that a person can inhale (breathe in) and exhale (breathe out). This test provides important information about lung function and is often used to assess respiratory conditions such as asthma, chronic obstructive pulmonary disease (COPD), and other lung diseases. Learn more about Spirometry.
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Tuberculosis (TB)
Tuberculosis (TB) is an infectious disease caused by the bacterium Mycobacterium tuberculosis. It primarily affects the lungs but can also affect other parts of the body, such as the kidneys, spine, and brain. TB is a serious global health concern, with millions of new cases reported each year. Learn more about Tuberculosis (TB).
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Whooping cough
Whooping cough, also known as pertussis, is a highly contagious respiratory infection caused by the bacterium Bordetella pertussis. It is characterized by severe coughing spells that are often followed by a “whooping” sound when the person tries to inhale air after coughing. Learn more about Whooping cough.
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