ostium

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Related to ostium: Ostium primum, Ostium secundum

os·ti·um

(ŏs′tē-əm)

n. pl. os·ti·a (-tē-ə)

1. A small opening or orifice, as in a body organ or passage.

2. Any of the small openings or pores in a sponge, through which water is drawn in.

[Latin ōstium, door, opening, from ōs, mouth; see ōs- in Indo-European roots.]

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

ostium

(ˈɒstɪəm)

n, pl -tia (-tɪə)

1. (Zoology) any of the pores in sponges through which water enters the body

2. (Zoology) any of the openings in the heart of an arthropod through which blood enters

3. (Biology) any similar opening

[C17: from Latin: door, entrance]

Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

os•ti•um

(ˈɒs ti əm)

n., pl. -ti•a (-ti ə)

a small opening or orifice of the body.

[1655–65; < Latin ōstium entrance, river mouth]

Translations

ostium

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References in periodicals archive ?

The term maxillo-ostio-choanal polyp was deemed appropriate in cases where it originates in the maxillary sinus ostium mucosa.

Maxillo Ostio Choanal Polyp

A single PV potential closely following or fused with an atrial potential in the ostium of the PVs is the most commonly observed pattern during sinus rhythm (SR) [7, 8].

Concealed Pulmonary Vein Bigeminy during Sinus Rhythm in Patients with Paroxysmal Atrial Fibrillation: A Useful Marker for Pulmonary Vein Firing

The presence of RCMs, osteomeatal complex obstruction (OMCO), an accessory ostium, and abnormalities of the middle turbinate (AMT) were evaluated independently for the right and left sides.

Paranasal Sinus Anatomic Variations Accompanying Maxillary Sinus Retention Cysts: A Radiological Analysis

An unusual medial ostium of a concha bullosa of the middle turbinate.

Endoscopic view of a drainage pathway of a concha bullosa

The aim of the present study is to assess the normal anatomy and variations of SA nodal artery by studying the number, origin, course, length and distance of its origin from the ostium of parent artery.

A study on anatomy and variations of sinoatrial nodal artery

The distance of an individual ostium from the base of cusps of aortic valve by using Vernier caliper (Figure 2).

A cadaveric study on the anatomical variations of origin of the coronary arteries in Gujarat state

In this case, the aneurysm extended into the coronary artery ostium. Coronary artery aneurysm, in contrast, is defined as coronary artery dilatation which exceeds the diameter of the largest normal coronary artery by 1.5 times.

Severe Dilatation of Coronary Artery Ostium Complicating Sinus of Valsalva Aneurysm: Differential Diagnosis and Review of the Literature

According to the Neri's definition of coronary malperfusion in aortic dissection,[sup][2] we differentiated among three types of lesions based upon operative findings: type A ( n = 23), ostial dissection is defined as a disruption of the inner layer limited to the area of the coronary ostium without disrupting coronary vessel; type B ( n = 8), dissection with a coronary false channel; and type C ( n = 5), circumferential detachment with an inner cylinder intussusception.

Surgical Treatment of Coronary Malperfusion with Acute Type A Aortic Dissection

DIAGNOSIS: Arm-lead reversal; normal sinus right atrial enlargement and right ventricular enlargement suggesting an ostium secundum atrial septal defect; acute inferior myocardial infarction.

ECG in a 44-year-old man with chest pain

Bony ostium was enlarged to an extent of approximately 1x1.5cm, bone overlying the upper part of nasolacrimal duct was also removed.

Outcome and complications of endoscopic dacryocystorhinostomy without stenting

The above abnormality was accompanied by an ostium secundum-type atrial septal defect.