how to read imageDatastore for 4D-single.

Dear all,

My data is 4D-single. Anyone know how to read imageDatastore for 4D-single.

the code volds is for mage data set 3D MxNxN

clc
clear all
close all
%testDataimages
DATASetDir = fullfile('C:\Users\USER\Downloads\BrainTS\preprocessedDataset');
IMAGEDir = fullfile(DATASetDir,'imagesTr');
volReader = @(x) matRead(x);
volds = imageDatastore(IMAGEDir, ...
    'FileExtensions','.mat','ReadFcn',volReader); %THIS ONE IS DATA FOR MXNXN

% labelReader = @(x) matread(x);
matFileDir = fullfile('C:\Users\USER\Downloads\BrainTS\preprocessedDataset\labelsTr');
classNames = ["background", "tumor"];
pixelLabelID = [0 1];
% pxds = (LabelDirr,classNames,pixelLabelID, ...
%     'FileExtensions','.mat','ReadFcn',labelReader);
pxds = pixelLabelDatastore(matFileDir,classNames,pixelLabelID, ...
    'FileExtensions','.mat','ReadFcn',@matRead);