12-carotid_ultrasound

12 - carotid ultrasound

Carotid intima-media thickness (CIMT) measurement is an ultrasound-based technique used to assess the thickness of the innermost two layers of the carotid artery, known as the intima and media. These layers can become thickened due to atherosclerotic processes or due to age. The thickening of the intima-media layer can be throughout the length of the artery (increased IMT) or as local accumulation of fatty deposits that penetrate into the vessel interior known as plaques. Advanced plaques can cause stenosis of the artery. . Carotid IMT is increasingly used as an indicator of early atherosclerosis and a predictor for cardiovascular events and can be used for identifying asymptomatic patients at high risk who might be candidates for more intensive medical interventions. Measurement of CIMT with B-mode ultrasound is a noninvasive, sensitive, and reproducible technique for identifying and quantifying subclinical vascular disease and for evaluating CVD risk.

The ultrasound probe is placed on the skin over the carotid artery and high-frequency sound waves are used to produce images of the artery. These images are then analyzed using an automatic detection algorithm to measure the thickness of the intima and media layers.

Measurement protocol: Carotid US was performed using the Supersonic Aixplorer MACH 30 (Hologic, USA). Carotid Intima Media (CIMT) was measured using the L10-2 transducer from both carotid arteries while the subject in supine position with head rotated to the opposite side of the measured artery. Evaluation was performed using an automatic computerized system (Aixplorer Mach 30). The intima and media are automatically traced within the box of interest. Mean CIMT was recorded over a length of 1 cm at the far wall of each carotid artery. One measurement was obtained from each carotid artery. Only parts of the carotid artery without plaques were included in the IMT analysis.

The information is stored in 1 parquet file: carotid_us.parquet

from pheno_utils import PhenoLoader

dl = PhenoLoader('carotid_ultrasound', age_sex_dataset=None)
dl

DataLoader for carotid_ultrasound with
9 fields
1 tables: ['carotid_us']

dl.dict

	field_string	description_string	parent_dataframe	relative_location	value_type	units	sampling_rate	item_type	array	cohorts	data_type	debut	pandas_dtype
tabular_field_name
timezone	Timezone	Timezone	NaN	carotid_us.parquet	Text	NaN	NaN	Data	Single	10k	tabular	2021-08-16	string
collection_date	Collection date (YYYY-MM-DD)	Collection date (YYYY-MM-DD)	NaN	carotid_us.parquet	Date	None	NaN	Data	Single	10k	tabular	2021-08-16	datetime64[ns]
collection_timestamp	Collection timestamp	Collection timestamp	NaN	carotid_us.parquet	Time	NaN	Data	Data	Single	10k	tabular	2021-08-16	datetime64[ns, Asia/Jerusalem]
imt_left	Intima media thickness (left)	Intima Media Thickness	NaN	carotid_us.parquet	Continuous	mm	NaN	Data	Single	10k	tabular	2021-08-16	float
imt_right	Intima media thickness (right)	Intima Media Thickness	NaN	carotid_us.parquet	Continuous	mm	NaN	Data	Single	10k	tabular	2021-08-16	float
imt_window_width_left	IMT window width (left)	Indicates the width if the box of interest	NaN	carotid_us.parquet	Continuous	mm	NaN	Data	Single	10k	tabular	2021-08-16	float
imt_window_width_right	IMT window width (right)	Indicates the width if the box of interest	NaN	carotid_us.parquet	Continuous	mm	NaN	Data	Single	10k	tabular	2021-08-16	float
imt_fit_left	Intima media thickness Fit (left)	Percentage of the box of interest for which th...	NaN	carotid_us.parquet	Continuous	%	NaN	Data	Single	10k	tabular	2021-08-16	float
imt_fit_right	Intima media thickness Fit (right)	Percentage of the box of interest for which th...	NaN	carotid_us.parquet	Continuous	%	NaN	Data	Single	10k	tabular	2021-08-16	float