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18 results found

Brain tumour protocol (MRI)

MRI protocol for brain tumour assessment is a group of MRI sequences put together to best approach CNS tumours in general. Note: This article is intended to outline some general principles of protocol design. The specifics will vary depending on MRI hardware and software, radiologist's and refe...

Calvarial doughnut lesion

Calvarial doughnut lesions are radiolucent ring-like skull defects, with surrounding sclerotic halo, which may have central bone density, and may occur in any part of the skull. Epidemiology Most of these lesions occur in middle life and old age, but it also may happen in juvenile skulls 1,2. ...

Cerebral angiography

Cerebral angiography is an interventional procedure for the diagnosis and/or treatment of intracranial pathology. Indications Cerebral digital subtraction angiography (DSA) is indicated in a variety of settings including: diagnosis and treatment of: aneurysms acute ischaemic stroke vascula...

CT head (technique)

CT head technique describes how a CT head is performed. Technique The technique for performing a CT of the head depends on the scanner available and fall into two broad camps:  step-and-shoot volumetric acquisition (most common) Step-and-shoot Step-and-shoot scanning was the first describe...

Hair artifact

Hair artifact and hair-product artifacts are artifacts produced by the presence of the patient's hair across the field of view during acquisition of an image, which can affect all modalities to varying degrees. For example, in mammography, hair may appear as curvilinear white lines or may simula...

Intraosseous pseudomeningocele

An intraosseous pseudomeningocele is an intradiploic CSF collection communicating with the subarachnoid space. Epidemiology Intraosseous pseudomeningoceles are rare sequelae of a skull fractures of traumatic or iatrogenic ethology occurring in infants and young children. They can be seen in an...


Lipiodol® (also known as ethiodized oil) is an oil-based iodinated contrast medium that was historically used for myelography and hysterosalpingography. It was later superseded by newer, less hazardous, agents, and now is used primarily as a therapeutic agent. Guerbet is now the sole manufacture...

Normal brain imaging examples

This article lists examples of normal imaging of the brain and surrounding structures, divided by modality and protocol. CT CT (routine) example 1: C- axial, coronal, sagittal example 2: C- axial, coronal, sagittal & axial bone example 3: C- axial, C+ axial, coronal, sagittal example 4: C-...

Normal head and neck imaging examples

This article lists examples of normal imaging of the head and neck and surrounding structures, divided by region and modality. Neck For normal spinal imaging, please see: normal spinal imaging Plain radiographs soft tissue: example 1, example 2 Ultrasound example 1 CT soft tissue contra...

Normal spine imaging examples

This article lists examples of normal imaging of the spine and surrounding structures, divided by region and modality. Cervical spine plain films example 1: AP, lat, obliques only example 2: PEG view example 3: flexion and extension views only example 4: paediatric - 12 years old example ...

Orbitomeatal line

The orbitomeatal line, also known as the canthomeatal line, was the traditional axial plane used for CT of the brain. It was easily identified on the inspection of the patient's head when tilting the gantry or patient's head to achieve a standard axial plane.  The orbitomeatal line was defined ...

Pineal and tectal plate protocol (MRI)

MRI protocol for the pineal and tectal plate assessment is a group of MRI sequences put together to best approach tumours involving this region.  The pineal region is best imaged with MRI although CT, angiography, and ultrasound (in infants) also play a role. Please refer to the article pineal ...

Radionuclide cisternography

Radionuclide cisternography is a nuclear medicine imaging technique that uses intrathecal 111In-DTPA (diethyletriaminepentaacetic acid; pentetate) to visualise the flow of cerebrospinal fluid (CSF). There are few indications 1: localisation of CSF leak, such as in spontaneous intracranial hypo...

Skull (AP view)

The skull AP view is a nonangled AP radiograph of the skull. This view provides an overview of the entire skull rather than attempting to highlight any one region. Patient position the back of patient's head is placed against the image detector Technical factors anterior-posterior projection...

Skull (lateral view)

The skull lateral view is a nonangled lateral radiograph of the skull. This view provides an overview of the entire skull rather than attempting to highlight any one region. Patient position the sagittal midline of the patient's head is parallel to the image detector sella turcica in profile ...

Skull (PA view)

The skull PA view is a non-angled PA radiograph of the skull. This view provides an overview of the entire skull rather than attempting to highlight any one region. Patient position the patient is erect the patient's forehead is placed against the image detector allowing for the nose to be in...

Skull radiography

Skull radiography is the radiological investigation of the skull vault and associated bony structures. Seldom requested in modern medicine, plain radiography of the skull is often a last resort in trauma imaging in the absence of a CT. However, it is still utilised in the setting of skeletal sur...

Transcranial Doppler sonography (ultrasound)

Transcranial​ ​Doppler​ ​(TCD)​, also known as transcranial colour-coded duplex sonography (TCCS) is a sonographic study of intracranial structures and blood vessels, used most commonly to identify the haemodynamic state present in the vertebrobasilar circulation and the circle of Willis.  Term...

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