diff --git a/pkgs/by-name/ot/otb/itk_4_13/itk-1-fftw-all.diff b/pkgs/by-name/ot/otb/itk_4_13/itk-1-fftw-all.diff
deleted file mode 100644
index 8b7769bfb6b1..000000000000
--- a/pkgs/by-name/ot/otb/itk_4_13/itk-1-fftw-all.diff
+++ /dev/null
@@ -1,31 +0,0 @@
-diff -burN InsightToolkit-4.10.0.orig/CMake/FindFFTW.cmake InsightToolkit-4.10.0/CMake/FindFFTW.cmake
---- InsightToolkit-4.10.0.orig/CMake/FindFFTW.cmake	2016-06-16 14:21:15.226203872 +0200
-+++ InsightToolkit-4.10.0/CMake/FindFFTW.cmake	2016-06-16 14:23:48.966202670 +0200
-@@ -35,14 +35,12 @@
-   set(FFTW_LIB_SEARCHPATH
-     ${FFTW_INSTALL_BASE_PATH}/lib
-     ${FFTW_INSTALL_BASE_PATH}/lib64
--    /usr/lib/fftw
--    /usr/local/lib/fftw
-   )
- 
-   if(ITK_USE_FFTWD)
-     mark_as_advanced(FFTWD_LIB)
--    find_library(FFTWD_LIB fftw3 ${FFTW_LIB_SEARCHPATH}) #Double Precision Lib
--    find_library(FFTWD_THREADS_LIB fftw3_threads ${FFTW_LIB_SEARCHPATH}) #Double Precision Lib only if compiled with threads support
-+    find_library(FFTWD_LIB fftw3 ${FFTW_LIB_SEARCHPATH} NO_DEFAULT_PATH) #Double Precision Lib
-+    find_library(FFTWD_THREADS_LIB fftw3_threads ${FFTW_LIB_SEARCHPATH} NO_DEFAULT_PATH) #Double Precision Lib only if compiled with threads support
- 
-     if(FFTWD_LIB)
-       set(FFTWD_FOUND 1)
-@@ -55,8 +53,8 @@
- 
-   if(ITK_USE_FFTWF)
-     mark_as_advanced(FFTWF_LIB)
--    find_library(FFTWF_LIB fftw3f ${FFTW_LIB_SEARCHPATH}) #Single Precision Lib
--    find_library(FFTWF_THREADS_LIB fftw3f_threads ${FFTW_LIB_SEARCHPATH}) #Single Precision Lib only if compiled with threads support
-+    find_library(FFTWF_LIB fftw3f ${FFTW_LIB_SEARCHPATH} NO_DEFAULT_PATH) #Single Precision Lib
-+    find_library(FFTWF_THREADS_LIB fftw3f_threads ${FFTW_LIB_SEARCHPATH} NO_DEFAULT_PATH) #Single Precision Lib only if compiled with threads support
- 
-     if(FFTWF_LIB)
-       set(FFTWF_FOUND 1)
diff --git a/pkgs/by-name/ot/otb/itk_4_13/itk-2-itktestlib-all.diff b/pkgs/by-name/ot/otb/itk_4_13/itk-2-itktestlib-all.diff
deleted file mode 100644
index dc0b0cbdbb7e..000000000000
--- a/pkgs/by-name/ot/otb/itk_4_13/itk-2-itktestlib-all.diff
+++ /dev/null
@@ -1,35 +0,0 @@
-diff -burN InsightToolkit-4.12.0.orig/Modules/ThirdParty/VNL/src/CMakeLists.txt InsightToolkit-4.12.0/Modules/ThirdParty/VNL/src/CMakeLists.txt
---- InsightToolkit-4.12.0.orig/Modules/ThirdParty/VNL/src/CMakeLists.txt	2017-08-22 11:53:55.960938649 +0200
-+++ InsightToolkit-4.12.0/Modules/ThirdParty/VNL/src/CMakeLists.txt	2017-08-22 11:56:07.289820954 +0200
-@@ -18,10 +18,14 @@
- # Retrive the variable type to CACHE.
- set(BUILD_EXAMPLES ${BUILD_EXAMPLES} CACHE BOOL "Build the examples from the ITK Software Guide." FORCE)
- 
--foreach(lib itkvcl itkv3p_netlib itktestlib itkvnl itkvnl_algo itknetlib)
-+foreach(lib itkvcl itkv3p_netlib itkvnl itkvnl_algo itknetlib)
-   itk_module_target(${lib} NO_INSTALL)
- endforeach()
- 
-+if(BUILD_TESTING)
-+  itk_module_target(itktestlib NO_INSTALL)
-+endif()
-+
- foreach(exe
-     netlib_integral_test
-     netlib_lbfgs_example
-diff -burN InsightToolkit-4.12.0.orig/Modules/ThirdParty/VNL/src/vxl/core/CMakeLists.txt InsightToolkit-4.12.0/Modules/ThirdParty/VNL/src/vxl/core/CMakeLists.txt
---- InsightToolkit-4.12.0.orig/Modules/ThirdParty/VNL/src/vxl/core/CMakeLists.txt	2017-08-22 11:53:55.960938649 +0200
-+++ InsightToolkit-4.12.0/Modules/ThirdParty/VNL/src/vxl/core/CMakeLists.txt	2017-08-22 11:56:56.410150930 +0200
-@@ -131,8 +131,10 @@
-   set(CORE_VIDEO_FOUND OFF CACHE INTERNAL "VXL core video libraries built")
- endif ()
- 
--# common test executable
--add_subdirectory(testlib)
-+# common test executable if testing enabled
-+if(BUILD_TESTING)
-+  add_subdirectory(testlib)
-+endif()
- 
- # Tests that check and output the vxl configuration
- # NOTE: some external projects remove the tests directory (aka ITK)
diff --git a/pkgs/by-name/ot/otb/itk_4_13/itk-3-remove-gcc-version-debian-medteam-all.diff b/pkgs/by-name/ot/otb/itk_4_13/itk-3-remove-gcc-version-debian-medteam-all.diff
deleted file mode 100644
index 4ee283976202..000000000000
--- a/pkgs/by-name/ot/otb/itk_4_13/itk-3-remove-gcc-version-debian-medteam-all.diff
+++ /dev/null
@@ -1,104 +0,0 @@
---- a/Modules/ThirdParty/VNL/src/vxl/vcl/vcl_compiler.h
-+++ b/Modules/ThirdParty/VNL/src/vxl/vcl/vcl_compiler.h
-@@ -43,85 +43,7 @@
- #endif
- 
- #if defined(__GNUC__) && !defined(__ICC) // icc 8.0 defines __GNUC__
--# define VCL_GCC
--# if (__GNUC__ < 4)
--#  error "forget it."
--# elif (__GNUC__==4)
--#  define VCL_GCC_4
--#  if (__GNUC_MINOR__ > 0 )
--#   define VCL_GCC_41
--#  else
--#   define VCL_GCC_40
--#  endif
--# elif (__GNUC__==5)
--#  define VCL_GCC_5
--#  if (__GNUC_MINOR__ > 2 )
--#   define VCL_GCC_53
--#  elif (__GNUC_MINOR__ > 1 )
--#   define VCL_GCC_52
--#  elif (__GNUC_MINOR__ > 0 )
--#   define VCL_GCC_51
--#  else
--#   define VCL_GCC_50
--#  endif
--# elif (__GNUC__==6)
--#  define VCL_GCC_6
--#  if (__GNUC_MINOR__ > 2 )
--#   define VCL_GCC_63
--#  elif (__GNUC_MINOR__ > 1 )
--#   define VCL_GCC_62
--#  elif (__GNUC_MINOR__ > 0 )
--#   define VCL_GCC_61
--#  else
--#   define VCL_GCC_60
--#  endif
--# elif (__GNUC__==7)
--#  define VCL_GCC_7
--#  if (__GNUC_MINOR__ > 2 )
--#   define VCL_GCC_73
--#  elif (__GNUC_MINOR__ > 1 )
--#   define VCL_GCC_72
--#  elif (__GNUC_MINOR__ > 0 )
--#   define VCL_GCC_71
--#  else
--#   define VCL_GCC_70
--#  endif
--# elif (__GNUC__==8)
--#  define VCL_GCC_8
--#  if (__GNUC_MINOR__ > 2 )
--#   define VCL_GCC_83
--#  elif (__GNUC_MINOR__ > 1 )
--#   define VCL_GCC_82
--#  elif (__GNUC_MINOR__ > 0 )
--#   define VCL_GCC_81
--#  else
--#   define VCL_GCC_80
--#  endif
--# elif (__GNUC__==9)
--#  define VCL_GCC_9
--#  if (__GNUC_MINOR__ > 2 )
--#   define VCL_GCC_93
--#  elif (__GNUC_MINOR__ > 1 )
--#   define VCL_GCC_92
--#  elif (__GNUC_MINOR__ > 0 )
--#   define VCL_GCC_91
--#  else
--#   define VCL_GCC_90
--#  endif
--# elif (__GNUC__==10)
--#  define VCL_GCC_10
--#  if (__GNUC_MINOR__ > 2 )
--#   define VCL_GCC_103
--#  elif (__GNUC_MINOR__ > 1 )
--#   define VCL_GCC_102
--#  elif (__GNUC_MINOR__ > 0 )
--#   define VCL_GCC_101
--#  else
--#   define VCL_GCC_100
--#  endif
--# else
--#  error "Dunno about this gcc"
--# endif
-+# define VCL_GCC_73
- #endif
- 
- #if defined(_WIN32) || defined(WIN32)
---- a/Modules/ThirdParty/VNL/src/vxl/vcl/tests/test_preprocessor.cxx
-+++ b/Modules/ThirdParty/VNL/src/vxl/vcl/tests/test_preprocessor.cxx
-@@ -64,6 +64,12 @@
-   ++minor_count;
- #endif
- 
-+#ifdef VCL_GCC_73
-+  ++compiler_count;
-+  ++major_count;
-+  ++minor_count;
-+#endif
-+
- #ifdef VCL_VC
-   ++compiler_count;
- #endif
diff --git a/pkgs/by-name/ot/otb/itk_4_13/package.nix b/pkgs/by-name/ot/otb/itk_4_13/package.nix
deleted file mode 100644
index 7de4254392ad..000000000000
--- a/pkgs/by-name/ot/otb/itk_4_13/package.nix
+++ /dev/null
@@ -1,147 +0,0 @@
-{
-  lib,
-  stdenv,
-  fetchFromGitHub,
-  cmake,
-  expat,
-  fftw,
-  fftwFloat,
-  hdf5-cpp,
-  libjpeg,
-  libtiff,
-  libpng,
-  libuuid,
-  xz,
-  vtk,
-  zlib,
-}:
-# this ITK version is old and is only required for OTB package
-# https://gitlab.orfeo-toolbox.org/orfeotoolbox/otb/-/blob/develop/SuperBuild/CMake/External_itk.cmake?ref_type=heads#L149
-stdenv.mkDerivation (finalAttrs: {
-  pname = "itk";
-  version = "4.13.3";
-
-  src = fetchFromGitHub {
-    owner = "InsightSoftwareConsortium";
-    repo = "ITK";
-    rev = "v${finalAttrs.version}";
-    hash = "sha256-lcoJ+H+nVlvleBqbmupu+yg+4iZQ4mTs9pt1mQac+xg=";
-  };
-
-  # https://gitlab.orfeo-toolbox.org/orfeotoolbox/otb/-/tree/develop/SuperBuild/patches/ITK?ref_type=heads
-  patches = [
-    ./itk-1-fftw-all.diff
-    ./itk-2-itktestlib-all.diff
-    ./itk-3-remove-gcc-version-debian-medteam-all.diff
-  ];
-
-  # https://gitlab.orfeo-toolbox.org/orfeotoolbox/otb/-/blob/develop/SuperBuild/CMake/External_itk.cmake?ref_type=heads
-  cmakeFlags = [
-    "-DBUILD_TESTING=OFF"
-    "-DBUILD_EXAMPLES=OFF"
-    "-DBUILD_SHARED_LIBS=ON"
-    "-DITK_BUILD_DEFAULT_MODULES=OFF"
-    "-DITKGroup_Core=OFF"
-    "-DITK_FORBID_DOWNLOADS=ON"
-    "-DITK_USE_SYSTEM_LIBRARIES=ON" # finds common libraries e.g. hdf5, libpng, libtiff, libjpeg, zlib etc
-    "-DModule_ITKCommon=ON"
-    "-DModule_ITKFiniteDifference=ON"
-    "-DModule_ITKGPUCommon=ON"
-    "-DModule_ITKGPUFiniteDifference=ON"
-    "-DModule_ITKImageAdaptors=ON"
-    "-DModule_ITKImageFunction=ON"
-    "-DModule_ITKMesh=ON"
-    "-DModule_ITKQuadEdgeMesh=ON"
-    "-DModule_ITKSpatialObjects=ON"
-    "-DModule_ITKTransform=ON"
-    "-DModule_ITKTransformFactory=ON"
-    "-DModule_ITKIOTransformBase=ON"
-    "-DModule_ITKIOTransformInsightLegacy=ON"
-    "-DModule_ITKIOTransformMatlab=ON"
-    "-DModule_ITKAnisotropicSmoothing=ON"
-    "-DModule_ITKAntiAlias=ON"
-    "-DModule_ITKBiasCorrection=ON"
-    "-DModule_ITKBinaryMathematicalMorphology=ON"
-    "-DModule_ITKColormap=ON"
-    "-DModule_ITKConvolution=ON"
-    "-DModule_ITKCurvatureFlow=ON"
-    "-DModule_ITKDeconvolution=ON"
-    "-DModule_ITKDenoising=ON"
-    "-DModule_ITKDisplacementField=ON"
-    "-DModule_ITKDistanceMap=ON"
-    "-DModule_ITKFastMarching=ON"
-    "-DModule_ITKFFT=ON"
-    "-DModule_ITKGPUAnisotropicSmoothing=ON"
-    "-DModule_ITKGPUImageFilterBase=ON"
-    "-DModule_ITKGPUSmoothing=ON"
-    "-DModule_ITKGPUThresholding=ON"
-    "-DModule_ITKImageCompare=ON"
-    "-DModule_ITKImageCompose=ON"
-    "-DModule_ITKImageFeature=ON"
-    "-DModule_ITKImageFilterBase=ON"
-    "-DModule_ITKImageFusion=ON"
-    "-DModule_ITKImageGradient=ON"
-    "-DModule_ITKImageGrid=ON"
-    "-DModule_ITKImageIntensity=ON"
-    "-DModule_ITKImageLabel=ON"
-    "-DModule_ITKImageSources=ON"
-    "-DModule_ITKImageStatistics=ON"
-    "-DModule_ITKLabelMap=ON"
-    "-DModule_ITKMathematicalMorphology=ON"
-    "-DModule_ITKPath=ON"
-    "-DModule_ITKQuadEdgeMeshFiltering=ON"
-    "-DModule_ITKSmoothing=ON"
-    "-DModule_ITKSpatialFunction=ON"
-    "-DModule_ITKThresholding=ON"
-    "-DModule_ITKEigen=ON"
-    "-DModule_ITKNarrowBand=ON"
-    "-DModule_ITKNeuralNetworks=ON"
-    "-DModule_ITKOptimizers=ON"
-    "-DModule_ITKOptimizersv4=ON"
-    "-DModule_ITKPolynomials=ON"
-    "-DModule_ITKStatistics=ON"
-    "-DModule_ITKRegistrationCommon=ON"
-    "-DModule_ITKGPURegistrationCommon=ON"
-    "-DModule_ITKGPUPDEDeformableRegistration=ON"
-    "-DModule_ITKMetricsv4=ON"
-    "-DModule_ITKPDEDeformableRegistration=ON"
-    "-DModule_ITKRegistrationMethodsv4=ON"
-    "-DModule_ITKClassifiers=ON"
-    "-DModule_ITKConnectedComponents=ON"
-    "-DModule_ITKDeformableMesh=ON"
-    "-DModule_ITKKLMRegionGrowing=ON"
-    "-DModule_ITKLabelVoting=ON"
-    "-DModule_ITKLevelSets=ON"
-    "-DModule_ITKLevelSetsv4=ON"
-    "-DModule_ITKMarkovRandomFieldsClassifiers=ON"
-    "-DModule_ITKRegionGrowing=ON"
-    "-DModule_ITKSignedDistanceFunction=ON"
-    "-DModule_ITKVoronoi=ON"
-    "-DModule_ITKWatersheds=ON"
-  ];
-
-  nativeBuildInputs = [
-    cmake
-    xz
-  ];
-  buildInputs = [ libuuid ];
-  propagatedBuildInputs = [
-    # similar to 5.2.x, we propagate these inputs for OTB
-    expat
-    fftw
-    fftwFloat
-    hdf5-cpp
-    libjpeg
-    libpng
-    libtiff
-    zlib
-  ];
-
-  meta = {
-    description = "Insight Segmentation and Registration Toolkit";
-    homepage = "https://www.itk.org";
-    license = lib.licenses.asl20;
-    maintainers = with lib.maintainers; [ daspk04 ];
-    platforms = with lib.platforms; linux;
-  };
-})