C# Definition:

    [StructLayout(LayoutKind.Sequential)]
    public struct IMAGE_NT_HEADERS
    {
        public UInt32 Signature;
        public IMAGE_FILE_HEADER FileHeader;
        public IMAGE_OPTIONAL_HEADER32 OptionalHeader;
    }

VB Definition:

    <StructLayout(LayoutKind.Sequential)> _
    Public Structure IMAGE_NT_HEADERS
       Public Signature As UInt32
        Public FileHeader As IMAGE_FILE_HEADER
        Public OptionalHeader As IMAGE_OPTIONAL_HEADER32
    End Structure

User-Defined Field Types:

None.

Notes: