This dataset contains 20 labeled COVID-19 CT scans:

https://zenodo.org/record/3757476#.XtQBz1QzZdg

They are saved in .nii format (nifti) and you can find several tools for loading nifti images in MATLAB:

http://blogs.cuit.columbia.edu/bl2490/2012/10/08/tools-for-nifti-and-analyze-image-in-matlab-examples/

https://www.mathworks.com/matlabcentral/fileexchange/8797-tools-for-nifti-and-analyze-image

Here is an open dataset of 100 segmented axial CT slices from ~60 Italian patients:

http://medicalsegmentation.com/covid19

There is a good source of CT dataset in the following links hope it would be useful:

https://github.com/UCSD-AI4H/COVID-CT

https://www.kaggle.com/allen-institute-for-ai/CORD-19-research-challenge

https://www.news-medical.net/news/20200508/Worlds-largest-CT-scan-database-with-COVID-19-features-collected-in-Russia.aspx

https://github.com/ieee8023/covid-chestxray-dataset

Many thanks Fatemeh Abdolali for the very useful information.

Thank you Vahidreza Gharehbaghi for sharing the datasets.

thank you for sharing the dataset