diff --git a/third-party/imgui/impl/imgui_impl_vulkan.cpp b/third-party/imgui/impl/imgui_impl_vulkan.cpp
index aa6a3dd..d75a8e3 100644
--- a/third-party/imgui/impl/imgui_impl_vulkan.cpp
+++ b/third-party/imgui/impl/imgui_impl_vulkan.cpp
@@ -123,12 +123,12 @@ void ImGui_ImplVulkanH_CreateWindowCommandBuffers(VkPhysicalDevice physical_devi
 
 // Vulkan prototypes for use with custom loaders
 // (see description of IMGUI_IMPL_VULKAN_NO_PROTOTYPES in imgui_impl_vulkan.h
-#ifdef VK_NO_PROTOTYPES
+#if defined(VK_NO_PROTOTYPES) && !defined(VOLK_HEADER_VERSION)
 static bool g_FunctionsLoaded = false;
 #else
 static bool g_FunctionsLoaded = true;
 #endif
-#ifdef VK_NO_PROTOTYPES
+#if defined(VK_NO_PROTOTYPES) && !defined(VOLK_HEADER_VERSION)
 #define IMGUI_VULKAN_FUNC_MAP(IMGUI_VULKAN_FUNC_MAP_MACRO) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkAllocateCommandBuffers) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkAllocateDescriptorSets) \
@@ -1011,7 +1011,7 @@ bool    ImGui_ImplVulkan_LoadFunctions(PFN_vkVoidFunction(*loader_func)(const ch
     // You can use the default Vulkan loader using:
     //      ImGui_ImplVulkan_LoadFunctions([](const char* function_name, void*) { return vkGetInstanceProcAddr(your_vk_isntance, function_name); });
     // But this would be equivalent to not setting VK_NO_PROTOTYPES.
-#ifdef VK_NO_PROTOTYPES
+#if defined(VK_NO_PROTOTYPES) && !defined(VOLK_HEADER_VERSION)
 #define IMGUI_VULKAN_FUNC_LOAD(func) \
     func = reinterpret_cast<decltype(func)>(loader_func(#func, user_data)); \
     if (func == NULL)   \
diff --git a/third-party/imgui/impl/imgui_impl_vulkan.h b/third-party/imgui/impl/imgui_impl_vulkan.h
index c770d0c..08e3214 100644
--- a/third-party/imgui/impl/imgui_impl_vulkan.h
+++ b/third-party/imgui/impl/imgui_impl_vulkan.h
@@ -40,7 +40,7 @@
 #if defined(IMGUI_IMPL_VULKAN_NO_PROTOTYPES) && !defined(VK_NO_PROTOTYPES)
 #define VK_NO_PROTOTYPES
 #endif
-#include <vulkan/vulkan.h>
+#include "volk/volk.h"
 
 // Initialization data, for ImGui_ImplVulkan_Init()
 // [Please zero-clear before use!]