abnormal chest xray

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ABNORMAL CHEST XRAY

• Lung Parenchyma• Pleura• Hilum• Mediastinum• Diaphragm• Chest wall and bones

Parenchymal diseases

Increased radiographic

density

Predominantly Airspace

PredominantlyInterstitial

tissueDecreased radiographic

density

ALVEOLAR DISEASE VS INTERSTITIAL DISEASE

ALVEOLAR DISEASE

CONSOLIDATION• Alveolar space filled

with inflammatory exudate

• Interstitium and architecture remain intact

• The airway is patent• Radiologically:This

transcribes to ;• A density corresponding

to a segment or lobe• Airbronchogram• No significant loss of lung

volume

• DefinitionVisualization of bronchi within parenchymal consolidation.

• FindingsBranching lucencies surrounded by consolidative opacity.

• Differential

non-obstructive atelectasispneumoniapulmonary edemahemorrhagebronchoalveolar carcinomalymphoma

• Significance Excludes a pleural or mediastinal lesion

AIR BRONCHOGRAM SIGN

AIR BRONCHOGRAM SIGN

BULGING FISSURES SIGN• The bulging fissure

sign refers to LOBAR CONSOLIDATION where the affected portion of the lung is expanded.

• The most common infective causative agents are  

Klebsiella pneumoniaeStreptococcus pneumoniaePseudomonas aeruginosaStaphylococcus aureus

SILHOUETTE SIGN• An intra-thoracic radio-

opacity, if in anatomic contact with a border of heart , aorta or diaphragm , will obscure that border.

• An intra-thoracic lesion not anatomically contiguous with a border or a normal structure will not obliterate that border.

Right middle lobe disease

SILHOUETTE SIGN

APPLICATION

ITS NOT JUST IN PNEUMONIA

• In a small percentage of normal individual, the right heart border may not be seen

• A depressed sternum can produce loss of the right heart border, an appearance which mimics middle lobe pneumonia .This is because:

(a) the depressed sternum pushes the heart posteriorly and to the left; and (b) bunching of the soft tissues of the deformed chest wall causes an increase in density.

PITFALLS

• The absence of a silhouette sign can tell you where a shadow (consolidation or mass) is

NOT situated.

ITS NOT JUST THE PRESENCE

RT. MIDDLE LOBE PNEUMONIA

Indistinct borders, air bronchograms, and silhouetting of the right heart border.

COLLAPSEIn collapse air is absorbed and not replaced in contrast to consolidation.

• The signs of lobar or pulmonary collapse can be divided into

1) Direct

2) Indirect

COLLAPSE

Direct signs are;• Opacity of the affected lobe(s);• Crowding of the vessels and bronchi within the collapsed

area• Displacement or bowing of the fissures . Indirect signs are:• Compensatory hyperinflation of the normal lung • Displacement of the mediastinal structures toward the

affected side• Displacement of the ipsilateral hilum which changes shape • Elevation of the ipsilateral hemidiaphragm• Crowding of the ribs on the affected side

COLLAPSE

LEFT LUNG COLLAPSE

Golden S Sign:• Seen in case

of collapse due to a hilar mass

• The mass gives a convexity to the concave displaced fissure

COLLAPSE

DIFFERENCES

COLLAPSE Volume loss. Associated

ipsilateral shift Linear, wedge

shaped Apex at hilum Air bronchograms

are not seen

CONSOLIDATION Normal or increased

volume No shift, or if present

then contrlateral Consolidation, air

space process. Not centred at hilum Air bronchograms

are seen

INTERSTITIAL DISEASE

• Non-homogenous • Various patterns are : LinearSeptal Lines Milliary Shadow Reticulonodular, Nodular Honeycoomb ShadowingCystic Peribronchial Cuffing

DIFFUSE LUNG DISEASE

RETICULAR/LINEAR SHADOWING

• Appears as a fine irregular network of linear opacities

surrounding air –filled lung.

RETICULAR/LINEAR SHADOWING

Fine reticular patternCoarse reticular pattern

RETICULONODULAR SHADOWING• More common than

reticular or nodular shadowing alone.

• The nodules are less than 1cm in diameter.

• Ill defined and irregular in outline.

CAUSES OF DIFFUSE BILATERAL RETICULONODULAR SHADOWING

•Infections – Fungal, viruses, mycoplasma•Pneumoconiosis – Coal workers pneumoconiosis, silicosis,asbestosis•Collagen vascular diseases – SLE, Dermatomyositis, Scleroderma, rheumatoid lung•Cardiac – Pulmonary oedema, hemosiderosis , •Miscellaneous: Idopathic interstitial fibrosis, extrinsic allergic alveolitis, drugs, sarcoidosis, amyloidosis, alveolar proteinosis, lymphangitis carcinomatosis

HONEYCOMB SHADOWING• Air–containing spaces

with thick walls that are lined with bronchiolar epithelium and fibrous tissue.

• Due to destruction of alveoli and loss of acinar architecture

• Associated with pulmonary fibrosis.

• Usually 5-10 mm in size

LINEAR AND BAND SHADOWS• Normal structures such

as the blood vessels and fissures form linear shadows within the lung fields.

• However, there are many disease processes which may result in linear shadows.

• Linear shadows are less than 5 mm wide,

• Band shadows are greater than 5 mm thick .

• Pulmonary infarct• Sentinel Lines• Thickened Fissures• Pulmonary and pleural scars• Curvilinear shadows(Bullae/Pneumatocoele)• Plate atelectasis ( Fleischner Lines) etc

CAUSES

SENTINEL LINES• Mucus-filled bronchi • Coarse lines lying

peripherally in contact with the pleura and curving upwards.

• Often left-sided and associated with left lower lobe collapse.

• They may develop due to kinking of bronchi adjacent to the collapse.

KERLEY LINESKerley's A lines (arrows) : • Linear opacities extending from the periphery to

the hila• Due to distention of anastomotic channels

between peripheral and central lymphatics. Kerley's B lines (white arrowheads) : • Short horizontal lines situated perpendicularly to

the pleural surface at the lung base• Due to edema of the interlobular septa. Kerley's C lines (black arrowheads): Reticular opacities at the lung base representing superimposed Kerley's B lines.

KERLEY LINES

B

A

C

• Pulmonary oedema • Pneumoconiosis• Infections (viral, mycoplasma)• Lymphangiectasia• Mitral valve disease • Lymphangitis carcinomatosis• Interstitial pulmonary fibrosis• Lymphatic obstruction • Congenital heart disease • Sarcoidosis • Alveolar cell carcinoma• Lymphangiomyomatosis • Pulmonary venous occlusive disease .

CAUSES OF KERLY LINES

MILIARY PATTERN• Small discrete

opacities • 2-4 mm in

diameter • MC in Tuberculosis

OLD PLEURAL AND PULMONARY SCARS

• Scars are unchanged in appearance on serial film.

• Thin linear shadow often with associated pleural thickening and tenting of the diaphragm.

• Apical scarring is a common finding with healed tuberculosis, sarcoidosis and fungal disease

THICKENED BRONCHIAL WALLS• Parallel TRAMLINE

shadows • Ring shadows on end-on

view• They are common

finding in Bronchiectasis, Recurrent asthma, Bronchopulmonary aspergillosis , Pulmonary oedema Lymphangitis carcinomatosis.

• Discrete, well-marginated, rounded opacity• Less than or equal to 3 cm in diameter • Completely surrounded by lung parenchyma,

does not touch the hilum or mediastinum, • Not associated with adenopathy, atelectasis, or

pleural effusion. • Lesions larger than 4 cms are treated as

malignancies until proven otherwise.

SOLITARY PULMONARY NODULES

SOLITARY PULMONARY NODULES

A right lower lobe solitary pulmonary nodule that was later identified as a hamartoma.

Right lower lobe nodule later confirmed to be primary pulmonary lymphoma

SOLITARY PULMONARY NODULES• Intrapulmonary mass

forms an acute angle with the lung edge.

• Extrapleural and mediastinal masses form obtuse angles .

• A nodule is assessed for its size, shape and outline and for the presence of calcification or cavitation. .

ExtrapleuralMass

SOLITARY PULMONARY NODULES

• Carcinomas often have irregular, spiculated or notched margins.

• Calcification favours a benign lesion although a carcinoma may arise coincidentally at the site of an old calcified focus.

• Calcified metastases are rare, the primary tumour being usually an osteogenic or chondrosarcoma.

• Granulomas frequently calcify and are usually well defined and lobulated.

SOLITARY PULMONARY NODULES

HamartomaCalcified mets in Chondrosarcoma

MULTIPLE PULMONARY NODULES• Multiple small nodules

2-4 mm are called miliary shadows .

• Mostly metastases or tuberculous granulomas.

• Calcified nodules are generally benign except for metastases from bone or cartilaginous tumours.

Posteroanterior view of the chest showing multiplediffuse pulmonary nodules.

PULMONARY INFARCTS• These are variable in

appearance. • Usually wedge shaped

with base towards the periphery(HAMPTON’S HUMP)

• Resolve slowly over months decreasing in size (MELTING SIGN)

CAVITATING LESIONS AND CYSTS• It’s a gas filled space surrounded by a complete wall

which is 3 mm or greater in thickness.

• Thinner walled cavities are called CYSTS or ring shadows.

• Requires a patent airway to communicate with necrotic area

• Common cavitating processes are tuberculosis,

staphylococcal infections and carcinoma

CAVITATING LESIONSBronchogenic Ca

Cavitating Staphylococcal Pneumonia

Common sites of the Lesion• Tuberculous cavities : Upper zone and apical

segments of the lower lobes.• Lung abscesses following aspiration : Rightsided

and lower zone(patient position dependant)• Traumatic lung cysts : Subpleural• Amoebic abscesses : Right base ,infection

extending from the liver.• Pulmonary infarcts : Usually in lower lobes

CAVITATING LESION

CAVITATING LESIONTHICK WALLED• Acute abscesses• Most neoplasms

(usually squamous cell)

• Lymphoma • Most metastases • Wegener's granulomas • Rheumatoid nodules

THIN WALLED• Bulles • Pneumatoceles, • Cystic bronchiectasis• Hydatid cysts• Traumatic lung cysts• Chronic inactive

tuberculous cavities • Neoplasms

CAVITATING LESIONB/L Bullae Thick walled cavity

with air-fluid

FLUID LEVELS• Fluid levels are

common in primary tumors , and irregular masses of blood clot or necrotic tumor may be present.

• Fluid levels are uncommon in cavitating metastases and tuberculous cavities .

FLUID LEVELS ON A CHEST RADIOGRAPH

• Abscesses• Hydropneumothorax-Trauma, surgery, bronchopleural fistula• Oesophageal – pharyngeal pouch, diverticula Obstruction – tumours, achalasia• Mediastinal – Infections, oesophageal perforation• Pneumopericardium

AIR CRESCENT SIGNCrescent-shaped radiolucency within a parenchymal consolidation or nodular opacity Air fills the space between the devitalized tissue and surrounding parenchyma Opaque rim of hemorrhagic tissue peripheral to the radiolucencyCommon in Aspergilloma

WATER LILY SIGNRuptured hydatid cysts with daughter cysts floating within the cavity.

• Other intracavitory lesions include inspissated pus,blood clot and cavernoliths.

• Blood clot may form within cavitating neoplasms, tuberculosis and pulmonary infarcts

• Calcification is most easily recognized with low kVp films.

• In the elderly , calcification of the tracheal and bronchial cartilage is common.

• Tuberculosis is the commonest calcifying pulmonary process usually upper zone.

• Chickenpox foci are smaller (1-3 mm), regular in size and widely distributed.

CALCIFICATION

Pulmonary TB Chicken pox pneumonia

CALCIFICATION

CALCIFICATION

Punctate - Silicosis Irregular - Pleural Plaques

• Pleural caps • Pleural fluid • Bullae • Pancoast tumour• Pneumothorax• Infections-tuberculosis

COMMON CAUSES OF APICAL SHADOWS

APICAL SHADOWING

Apical pleural thickening/Pleural Cap • It is crescent shaped density • It may represent old pleural thickening • Also seen in Pancoast tumor – assess the ribs for

notching Lung apex• Commom site for Tb , fungal infection like

histoplasmosis , coccidioidomycosis, aspergillosis etc

APICAL SHADOWING

CAUSES OF AN OPAQUE HEMITHORAX• Technical . Rotation, scoliosis • Pleural. Hydrothorax, large effusion

Thickening, mesothelioma.• Surgical. Pneumonectomy,

thoracoplasty.• Congenital. Pulmonary agenesis.• Mediastinal . Cardiomegaly, Tumours.• Pulmonary . Collapse, consolidation, fibrosis

.• Diaphragmatic hernias

• Comparision of lungs should reveal any focal or generalized abnormality of transradiancy.

• Look for signs of obstructive or compensatory emphysema such as

o splaying of the ribso separation of the vascular markingso mediastinal displacemento depression of the hemidiaphragm

UNILATERAL HYPERTRANSLUCENCY

• Most common causes : Patient rotation and scoliosis

• With rotation to the left, the left side becomes more radiolucent.

• Mastectomy is another important cause. An

abnormal axillary fold is seen following a radical mastectomy.

UNILATERAL HYPERTRANSLUCENCY

UNILATERAL HYPERTRANSLUCENCY

MastectomyObstructive Emphysema

PLEURAL ABNORMALITIES

• Pleural effusion.• Pleural fibrosis/Thickening.• Pleural plaques.• Pleural calcification.• Pleural tumors.• Pneumothorax• Fibrothorax

PLEURAL ABNORMALITIES

PLEURAL EFFUSION• Fluid in the pleural

cavity.• Erect CXR- commonest

appearance is an opaque meniscus at costophrenic angle.

• If the effusion is very large entire hemithorax may be opaque and heart may be pushed to the normal side.

Features on CXR:• Blunting of the costophrenic angle• Blunting of the cardiophrenic angle• Fluid within the horizontal or oblique fissures• A meniscus will be seen, on frontal films seen laterally

and gently sloping medially • With large volume effusions, mediastinal shift occurs

away from the effusion

Approximately 200 ml of fluid are needed to detect an effusion in the frontal film vs.

approximately 75ml for the lateral

PLEURAL EFFUSION

• LAMELLAR EFFUSION: Shallow collections between the lung surface and the visceral pleura sometimes sparing the costophrenic angle.

• LOCULATED EFFUSION: Effusion within the fissures.

ATYPICAL EFFUSION

ATYPICAL EFFUSION

SUBPULMONIC EFFUSION • Effusions accumulate between the diaphragm and

undersurface of a lung.The following features are helpful :• Right: peak of the hemidiaphragm is shifted

laterally• Left: increased distance between lower lobe air

and gastric air bubble

SUBPULMONIC EFFUSION

PLEURAL PLAQUES• Plaques are focal areas of

thickening of parietal pleura due to previous exposure to asbestosis.

• Characteristically appear as scattered islands of well circumscribed pleural densities.

• Most commonly seen posteriorly and laterally, predominantly affecting the lower third of the thorax.

• Do not involve the CP angles .• May be calcified.

PLEURAL CALCIFICATION

True calcification• Calcified pleural plaques from

asbestos exposure : typically has sparing of costophernic angles

• Haemothorax• Infection involving the pleura

- e.g pyothorax / empyema• Tuberculous pleuritis• extra skeletal osteosarcomaof

pleura .

• Refers to the presence of gas in the pleural space.• Open Pneumothorax: If air can move in and out of

pleural space during respiration• Closed Penumothorax: No movement of air occurs• Valvular : Air enters pleural space on inspiration

but doesnot leave on expiration• When this collection is constantly enlarging with resulting compression of mediastinal structures it

is known as a tension pneumothorax.

PNEUMOTHORAX

DEEP SULCUS SIGN

• This sign refers to a deep collection of intrapleural air (pneumothorax) in the costophrenic sulcus as seen on the supine chest radiograph .

CXR APPEARANCES• Visible visceral pleural

edge see as a very thin, sharp white line

• No lung markings are seen peripheral to this line

• The peripheral space is radiolucent compared to adjacent lung 

• The lung may completely collapse

• No mediastinal shift unless a tension pneumothorax is present .

HYDROPNEUMOTHORAX• It is the concurrent

presence of a pneumothorax as well as a hydrothorax in the pleural space.

• On an erect chest

radiograph, classically seen as an air-fluid level.

FIBROTHORAX• Fibrosis within the pleural space• Occurs secondary to the inflammatory

response• Seen in TBAsbestosisHemothorax etc

HILAR ABNORMALITIES

• Superior margin of left hilum is normally higher than the right.

• Whenever a left hilum appears lower than right – check whether there is other evidence suggestive of collapse of either left lower lobe or of right upper lobe ; or enlargement of right hilum(eg; tumor or nodes)

HILAR ABNORMALITIES

• Bilateral hilar enlargement -Enlarged lymph nodes, or vascular enlargment.

• Unilateral enlargement : MC due to neoplasm or infections such as tuberculosis and whooping cough.

• Nodes affected by lymphoma are often asymmetrically involved.

• Bilateral involvement occurs with sarcoidosis, silicosis and leukaemia

HILAR ENLARGEMENT

HILAR ABNORMALITY

MEDIASTINAL ABNORMALITIES

MEDIASTINAL ABNORMALITIES

• Used to discern the anterior or posterior location of a lesion in the superior mediastinum on frontal chest radiographs. 

• The anterior mediastinum stops at the level of the superior clavicle.

• Thus when a mass extends above the superior clavicle, it is located either in the neck or in the posterior mediastinum.

• When lung tissue comes between the mass and the neck, the mass is probably in the posterior mediastinum.

CERVICOTHORACIC SIGN

CERVICOTHORACIC SIGNA mass extending above the level of the clavicle and there is lung tissue in front of it, so this must be a mass in the posterior mediastinum.

ANTERIOR MEDIASTINAL MASS

T cell lymphoma

Anterior mediastinal masses consist of the 4 "T's" (Terrible lymphoma, Thymic tumors, Teratoma, Thyroid mass) and aortic aneurysm, pericardial cyst, epicardial fat pad. 

RETROSTERNAL GOITRE• Retrosternal goitre

The plain chest film shows a large superior mediastinal mass narrowing the trachea

MIDDLE MEDIASTINAL MASS MC:L

ymphadenopathy due to metastases or primary tumor. 

Other causes include

hiatial hernia, aortic aneurysm, thyroid mass, duplication cyst bronchogenic cyst.  

Esophageal duplication cyst

POSTERIOR MEDIASTINAL MASS

Mass is detected by a pleural margin search along the superomedial part of right lung.  The interface is interrupted.

The differentials• Neoplasm, Lymphadenopathy, Aortic aneurysm. Neurenteric cyst or Lateral meningocele Extramedullary hematopoiesis.

• Lymphadenopathy is the next most frequent cause of a mediastinal swelling..

• Lymphadenopathy may occur in any of the three compartments and it is often possible to diagnose enlarged lymph nodes from their lobulated outlinesand the multiple locations involved.

Superior mediastinal lymph node enlargement. Note the bilateral lobular masses.

HILUM OVERLAY SIGN

• This sign is used to distinguish between cardiac enlargement and an anterior mediastinal mass, as follows;

• Hilum lateral to the lateral border of the “mass”– Cardiac enlargement.

• Hilum medial to the lateral border of mass”– Mediastinal mass.

HILUM OVERLAY SIGN

HILUM CONVERGENCE SIGN• Used to distinguish between a prominent

hilum and an enlarged pulmonary artery.

• If the pulmonary arteries converge into the lateral border of a hilar mass, the mass represents an enlarged pulmonary artery.

• If the convergence appears behind the abnormality or arises from the heart, a mediastinal mass is more likely.

HILUM CONVERGENCE SIGN

THORACOABDOMINAL SIGN• To localize the LOWER MEDIASTINAL MASS on frontal CXR

• It is the presence of extraluminal gas within the mediastinum.

AETIOLOGY• Blunt chest trauma• Secondary to chest, neck, or

retroperitoneal surgery• Esophageal perforation : – Boerhaave syndrome– Endoscopic intervention– Esophageal carcinoma

PNEUMOMEDIASTINUM

• Air around the pulmonary artery produces a black ring appearance.

• Air around the arteries arising from the aortic arch appears as a black rings and often referred to as the “ring around the artery sign”.

• Angel wing sign – represents the normal thymus surrounded by mediastinal air.

PNEUMOMEDIASTINUM- CXR APPEARANCES.

CONTINUOUS DIAPHRAGM SIGNContinuous lucency outlining

the base of the heart, representing Pneumomediastinum .

• Air in the mediastinum tracks extrapleurally, between the heart and diaphragm .

• Pneumopericardium can have a similar appearance but will show air circumferentially outlining the heart.

DIAPHRAGM

CAUSES OF A UNILATERAL ELEVATED DIAPHRAGM• Above diaphragm: phrenic nerve palsy; infiltration

from bronchial carcinoma or mediastinal tumour.• Diaphragm: eventration, more common on the left

and results from deficiency or atrophy of muscle.• Below diaphragm: right diaphragm elevation; liver

or subphrenic abscess, liver secondary deposits.

DIAPHRAGM

CAUSES OF BILATERAL ELEVATED DIAPHRAGMS• Obesity• Hepatosplenomegaly• Ascites • Pregnancy• Abdominal masses.

DIAPHRAGM

DIAPHRAGMATIC HERNIA• A congenital defect in

the diaphragm, more

common on the left, allows

bowel protrusion into the

thoracic cavity.

Eg: Hiatus Hernia Bochdalek Hernia Morgagni Hernia

EVENTRATION OF THE DIAPHRAGM• This is a congenital

condition in which the diaphragm lacks muscle and becomes a thin membranous sheet.

• The eventration may only involve part of one hemidiaphragm, resulting in a smooth 'hump

Localized eventration of the diaphragm. There is a smooth localized elevation of the medial half of the right hemidiaphragm (arrows

CHEST WALL ABNORMALITY

BONESCLAVICLE• Old healed fractures are frequent findings.• Erosion of the outer ends of the clavicles is

associated with rheumatoid arthritis and hyperparathyroidism.

• Hypoplastic clavicles are seen with the Holt-Oram syndrome and cleido cranial dysostosis

CHEST WALL ABNORMALITIES

Holt Oram Syndrome Rheumatoid arthritis

CLAVICULAR ABNORMALITY

• Sternal fractures are often due to a steering

wheel injury.

• Associated with congenital heart disease: Sternal agenesis, premature obliteration of the ossification centres and pigeon chest which are found

with ventricular septal defects.

STERNAL ABNORMALITIES

• Depressed sternum(Pectus Excavatum) - Atrial septal defects and Marfan's syndrome.

• Delayed epiphyseal fusion is a feature of cretinism

• Double ossification centres in the manubrium commonly occur in Down's syndrome

STERNAL ABNORMALITIES

RIB NOTCHING• It may affect the superior or

inferior surface and can be U/L or B/L

• Superior notching : Rheumatoid arthritis, SLE,hyperparathyroidism Marfan's syndrome, neurofibromatosis and in paraplegics and polio victims.

• Inferior notching develops as a result of hypertrophy of the intercostal vessels or with neurogenic tumours .

CAUSES OF INFERIOR RIB NOTCHING

CERVICAL RIB• A cervical rib in

humans is a supernumerary rib

 which arises from the seventh cervical vertebra.

• Congenital rib anomalies such as hypoplasia, bridging and bifid ribs are common.

RIB FRACTURE• The sixth to ninth ribs line are

the common sites for cough fractures.

• Stress fractures usually affect the first ribs.

• Pathological fractures may be due to senile osteoporosis, myeloma, Cushing's disease and other endocrine disorders, steroid therapy and diffuse metastases.

• Cushing's disease is associated with abundant callus formation

• Check for abnormal curvature or alignment , bone and disc destruction, sclerosis, paravertebral soft-tissue masses and congenital lesions such as butterfly vertebrae

• Anterior erosion of vertebral bodies sparing the disc spaces is noted with aneurysm of descending aorta, vascular tumors and neurofibromatosis.

• A single dense vertebra , the ivory vetebra, - classical appearance of lymphoma, but also – pagets disease and metastasis.

THORACIC SPINE

THORACIC SPINE

• Destruction of pedicle is typical of METASTASIS .

• Destruction of the disc with adjacent bony involvement is characteristic of an INFECTIVE

PROCESS.

• Disc calcification occurs in ochronosis and ankylosing spondylitis.

THORACIC SPINE

SOFT TISSUE ABNORMALITIESSkin lesions• Skin lesions including

naevi and lipomas may simulate lung tumours.

• Multiple nodules occur with neurofibromatosis .

• Mastectomy is one of the commonest causes of a translucent hemithorax

• Poland’s syndrome; There is a congenital absence of pectoralis

major and minor, associated with syndactyly and rib abnormalities .

SOFT TISSUE ABNORMALITIES

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