Halo sign

Last updated
Halo sign
Differential diagnosis temporal arteritis

In radiology, the halo sign is a finding of a dark halo around the arterial lumen on ultrasound that suggests the diagnosis of temporal arteritis. [1] The standard diagnostic test for temporal arteritis is biopsy; however, ultrasound and MRI show promise for replacing it. [2]

The halo sign of temporal arteritis should not be confused with Deuel's halo sign, which is a sign of fetal death. [3]

The halo sign is also understood as a region of ground-glass attenuation surrounding a pulmonary nodule on an X-ray computed tomography (CT scan) of the chest. It can be associated with hemorrhagic nodules, tumors, or inflammatory processes, but is most commonly known as an early radiographic sign of invasive pulmonary infection by the fungus species Aspergillus.

In nursing, the halo sign is the result of a test to see if drainage from a head injury contains cerebrospinal fluid. When a Dextrostix or Tes-Tape test gives a positive reading for glucose, the drainage must be further tested because glucose is also found in the blood. To perform the test, the leaking fluid is dripped onto a 4x4 gauze or towel. Positive results are indicated by blood coalescing into the center, leaving an outer ring of cerebrospinal fluid.

Related Research Articles

<span class="mw-page-title-main">Amniocentesis</span> Sampling of amniotic fluid done mainly to detect fetal chromosomal abnormalities

Amniocentesis is a medical procedure used primarily in the prenatal diagnosis of genetic conditions. It has other uses such as in the assessment of infection and fetal lung maturity. Prenatal diagnostic testing, which includes amniocentesis, is necessary to conclusively diagnose the majority of genetic disorders, with amniocentesis being the gold-standard procedure after 15 weeks' gestation.

<span class="mw-page-title-main">Pulmonary embolism</span> Blockage of an artery in the lungs

Pulmonary embolism (PE) is a blockage of an artery in the lungs by a substance that has moved from elsewhere in the body through the bloodstream (embolism). Symptoms of a PE may include shortness of breath, chest pain particularly upon breathing in, and coughing up blood. Symptoms of a blood clot in the leg may also be present, such as a red, warm, swollen, and painful leg. Signs of a PE include low blood oxygen levels, rapid breathing, rapid heart rate, and sometimes a mild fever. Severe cases can lead to passing out, abnormally low blood pressure, obstructive shock, and sudden death.

<span class="mw-page-title-main">Lumbar puncture</span> Procedure to collect cerebrospinal fluid

Lumbar puncture (LP), also known as a spinal tap, is a medical procedure in which a needle is inserted into the spinal canal, most commonly to collect cerebrospinal fluid (CSF) for diagnostic testing. The main reason for a lumbar puncture is to help diagnose diseases of the central nervous system, including the brain and spine. Examples of these conditions include meningitis and subarachnoid hemorrhage. It may also be used therapeutically in some conditions. Increased intracranial pressure is a contraindication, due to risk of brain matter being compressed and pushed toward the spine. Sometimes, lumbar puncture cannot be performed safely. It is regarded as a safe procedure, but post-dural-puncture headache is a common side effect if a small atraumatic needle is not used.

<span class="mw-page-title-main">Pleural effusion</span> Accumulation of excess fluid in the pleural cavity

A pleural effusion is accumulation of excessive fluid in the pleural space, the potential space that surrounds each lung. Under normal conditions, pleural fluid is secreted by the parietal pleural capillaries at a rate of 0.6 millilitre per kilogram weight per hour, and is cleared by lymphatic absorption leaving behind only 5–15 millilitres of fluid, which helps to maintain a functional vacuum between the parietal and visceral pleurae. Excess fluid within the pleural space can impair inspiration by upsetting the functional vacuum and hydrostatically increasing the resistance against lung expansion, resulting in a fully or partially collapsed lung.

<span class="mw-page-title-main">Prenatal testing</span> Testing for diseases or conditions in a fetus

Prenatal testing consists of prenatal screening and prenatal diagnosis, which are aspects of prenatal care that focus on detecting problems with the pregnancy as early as possible. These may be anatomic and physiologic problems with the health of the zygote, embryo, or fetus, either before gestation even starts or as early in gestation as practicable. Screening can detect problems such as neural tube defects, chromosome abnormalities, and gene mutations that would lead to genetic disorders and birth defects, such as spina bifida, cleft palate, Down syndrome, Tay–Sachs disease, sickle cell anemia, thalassemia, cystic fibrosis, muscular dystrophy, and fragile X syndrome. Some tests are designed to discover problems which primarily affect the health of the mother, such as PAPP-A to detect pre-eclampsia or glucose tolerance tests to diagnose gestational diabetes. Screening can also detect anatomical defects such as hydrocephalus, anencephaly, heart defects, and amniotic band syndrome.

In medical or research imaging, an incidental imaging finding is an unanticipated finding which is not related to the original diagnostic inquiry. As with other types of incidental medical findings, they may represent a diagnostic, ethical, and philosophical dilemma because their significance is unclear. While some coincidental findings may lead to beneficial diagnoses, others may lead to overdiagnosis that results in unnecessary testing and treatment, sometimes called the "cascade effect".

Oligohydramnios is a medical condition in pregnancy characterized by a deficiency of amniotic fluid, the fluid that surrounds the fetus in the abdomen, in the amniotic sac. It is typically diagnosed by ultrasound when the amniotic fluid index (AFI) measures less than 5 cm or when the single deepest pocket (SDP) of amniotic fluid measures less than 2 cm. Amniotic fluid is necessary to allow for normal fetal movement, lung development, and cushioning from uterine compression. Low amniotic fluid can be attributed to a maternal, fetal, placental or idiopathic cause and can result in poor fetal outcomes including death. The prognosis of the fetus is dependent on the etiology, gestational age at diagnosis, and the severity of the oligohydramnios.

Radiology (X-rays) is used in the diagnosis of tuberculosis. Abnormalities on chest radiographs may be suggestive of, but are never diagnostic of TB, but can be used to rule out pulmonary TB.

<span class="mw-page-title-main">Choroid plexus cyst</span> Medical condition

Choroid plexus cysts (CPCs) are cysts that occur within choroid plexus of the brain. They are the most common type of intraventricular cyst, occurring in 1% of all pregnancies.

<span class="mw-page-title-main">Zygomycosis</span> Medical condition

Zygomycosis is the broadest term to refer to infections caused by bread mold fungi of the zygomycota phylum. However, because zygomycota has been identified as polyphyletic, and is not included in modern fungal classification systems, the diseases that zygomycosis can refer to are better called by their specific names: mucormycosis, phycomycosis and basidiobolomycosis. These rare yet serious and potentially life-threatening fungal infections usually affect the face or oropharyngeal cavity. Zygomycosis type infections are most often caused by common fungi found in soil and decaying vegetation. While most individuals are exposed to the fungi on a regular basis, those with immune disorders (immunocompromised) are more prone to fungal infection. These types of infections are also common after natural disasters, such as tornadoes or earthquakes, where people have open wounds that have become filled with soil or vegetative matter.

<span class="mw-page-title-main">Hydrops fetalis</span> Human disease of fetuses

Hydrops fetalis or hydrops foetalis is a condition in the fetus characterized by an accumulation of fluid, or edema, in at least two fetal compartments. By comparison, hydrops allantois or hydrops amnion is an accumulation of excessive fluid in the allantoic or amniotic space, respectively.

<span class="mw-page-title-main">Hemothorax</span> Blood accumulation in the pleural cavity

A hemothorax is an accumulation of blood within the pleural cavity. The symptoms of a hemothorax may include chest pain and difficulty breathing, while the clinical signs may include reduced breath sounds on the affected side and a rapid heart rate. Hemothoraces are usually caused by an injury, but they may occur spontaneously due to cancer invading the pleural cavity, as a result of a blood clotting disorder, as an unusual manifestation of endometriosis, in response to Pneumothorax, or rarely in association with other conditions.

<span class="mw-page-title-main">Thoracentesis</span> Medical procedure

Thoracentesis, also known as thoracocentesis, pleural tap, needle thoracostomy, or needle decompression, is an invasive medical procedure to remove fluid or air from the pleural space for diagnostic or therapeutic purposes. A cannula, or hollow needle, is carefully introduced into the thorax, generally after administration of local anesthesia. The procedure was first performed by Morrill Wyman in 1850 and then described by Henry Ingersoll Bowditch in 1852.

<span class="mw-page-title-main">Ventriculomegaly</span> Increased size of the lateral ventricles

Ventriculomegaly is a brain condition that mainly occurs in the fetus when the lateral ventricles become dilated. The most common definition uses a width of the atrium of the lateral ventricle of greater than 10 mm. This occurs in around 1% of pregnancies. When this measurement is between 10 and 15 mm, the ventriculomegaly may be described as mild to moderate. When the measurement is greater than 15mm, the ventriculomegaly may be classified as more severe.

<span class="mw-page-title-main">Nuchal scan</span> Routine ultrasound done between 11 and 14 weeks pregnancy

A nuchal scan or nuchal translucency (NT) scan/procedure is a sonographic prenatal screening scan (ultrasound) to detect chromosomal abnormalities in a fetus, though altered extracellular matrix composition and limited lymphatic drainage can also be detected.

<span class="mw-page-title-main">Focused assessment with sonography for trauma</span> Fluid accumulation screening

Focused assessment with sonography in trauma is a rapid bedside ultrasound examination performed by surgeons, emergency physicians, and paramedics as a screening test for blood around the heart or abdominal organs (hemoperitoneum) after trauma. There is also the extended FAST (eFAST) which includes some additional ultrasound views to assess for pneumothorax.

<span class="mw-page-title-main">Thyroid nodule</span> Medical condition

Thyroid nodules are nodules which commonly arise within an otherwise normal thyroid gland. They may be hyperplastic or tumorous, but only a small percentage of thyroid tumors are malignant. Small, asymptomatic nodules are common, and often go unnoticed. Nodules that grow larger or produce symptoms may eventually need medical care. A goitre may have one nodule – uninodular, multiple nodules – multinodular, or be diffuse.

<span class="mw-page-title-main">Velamentous cord insertion</span> Velamentous placenta

Velamentous cord insertion is a complication of pregnancy where the umbilical cord is inserted in the fetal membranes. It is a major cause of antepartum hemorrhage that leads to loss of fetal blood and associated with high perinatal mortality. In normal pregnancies, the umbilical cord inserts into the middle of the placental mass and is completely encased by the amniotic sac. The vessels are hence normally protected by Wharton's jelly, which prevents rupture during pregnancy and labor. In velamentous cord insertion, the vessels of the umbilical cord are improperly inserted in the chorioamniotic membrane, and hence the vessels traverse between the amnion and the chorion towards the placenta. Without Wharton's jelly protecting the vessels, the exposed vessels are susceptible to compression and rupture.

Rheumatoid lung disease is a disease of the lung associated with RA, rheumatoid arthritis. Rheumatoid lung disease is characterized by pleural effusion, pulmonary fibrosis, lung nodules and pulmonary hypertension. Common symptoms associated with the disease include shortness of breath, cough, chest pain and fever. It is estimated that about one quarter of people with rheumatoid arthritis develop this disease, which are more likely to develop among elderly men with a history of smoking.

<span class="mw-page-title-main">Ground-glass opacity</span> Radiologic sign on radiographs and computed tomography scans

Ground-glass opacity (GGO) is a finding seen on chest x-ray (radiograph) or computed tomography (CT) imaging of the lungs. It is typically defined as an area of hazy opacification (x-ray) or increased attenuation (CT) due to air displacement by fluid, airway collapse, fibrosis, or a neoplastic process. When a substance other than air fills an area of the lung it increases that area's density. On both x-ray and CT, this appears more grey or hazy as opposed to the normally dark-appearing lungs. Although it can sometimes be seen in normal lungs, common pathologic causes include infections, interstitial lung disease, and pulmonary edema.

References

  1. Schmidt W, Kraft H, Vorpahl K, Völker L, Gromnica-Ihle E (1997). "Color duplex ultrasonography in the diagnosis of temporal arteritis". N Engl J Med. 337 (19): 1336–42. doi: 10.1056/NEJM199711063371902 . PMID   9358127.
  2. Bley TA, Brink I, Reinhard M (April 2006). "[Imaging procedures for giant cell arteritis (Horton's disease)]". Ophthalmologe (in German). 103 (4): 308–16. doi:10.1007/s00347-006-1323-x. PMID   16538476.
  3. Shaff MI (April 1975). "An evaluation of the radiological signs of fetal death". S. Afr. Med. J. 49 (18): 736–8. PMID   1169818.