DICOMファイルのコンテンツを理解することは、医療イメージの開発、トラブル解決、品質の確保に不可欠です このチュートリアルは、患者情報、研究の詳細、技術的なイメージパラメーターを抽出および表示するC#で総合的なディコムメタデータビューバーを構築する方法を示しています。
DICOMメタデータとは?
DICOM ファイルには 2 つの主要なコンポーネントが含まれています: ピクセルデータ (実際の画像) と メタデータ(画像に関する情報)。
- 患者人口学:名前、ID、出生日、性別
- 研究情報:日付、時間、説明、参照医師
- シリーズの詳細:モダリティ、身体部品、イメージプロトコル
- 画像パラメーター:サイズ、ピクセルスペース、ウィンドウ/レベル設定
- 機器情報:メーカー、モデル、ソフトウェア版
メタデータビューヤーは、開発者がデブギング、認証、データ分析のためにこれらの属性を検証するのに役立ちます。
基本メタデータ抽出
一般的なDICOM属性を抽出することから始めます:
using Aspose.Medical.Dicom;
public class DicomMetadataViewer
{
public DicomMetadata ExtractMetadata(string filePath)
{
DicomFile dicomFile = DicomFile.Open(filePath);
var dataset = dicomFile.Dataset;
return new DicomMetadata
{
// Patient Information
PatientName = dataset.GetString(DicomTag.PatientName),
PatientID = dataset.GetString(DicomTag.PatientID),
PatientBirthDate = dataset.GetString(DicomTag.PatientBirthDate),
PatientSex = dataset.GetString(DicomTag.PatientSex),
PatientAge = dataset.GetString(DicomTag.PatientAge),
// Study Information
StudyInstanceUID = dataset.GetString(DicomTag.StudyInstanceUID),
StudyDate = dataset.GetString(DicomTag.StudyDate),
StudyTime = dataset.GetString(DicomTag.StudyTime),
StudyDescription = dataset.GetString(DicomTag.StudyDescription),
AccessionNumber = dataset.GetString(DicomTag.AccessionNumber),
ReferringPhysician = dataset.GetString(DicomTag.ReferringPhysicianName),
// Series Information
SeriesInstanceUID = dataset.GetString(DicomTag.SeriesInstanceUID),
Modality = dataset.GetString(DicomTag.Modality),
SeriesDescription = dataset.GetString(DicomTag.SeriesDescription),
SeriesNumber = dataset.GetString(DicomTag.SeriesNumber),
BodyPartExamined = dataset.GetString(DicomTag.BodyPartExamined),
// Image Information
SOPInstanceUID = dataset.GetString(DicomTag.SOPInstanceUID),
SOPClassUID = dataset.GetString(DicomTag.SOPClassUID),
InstanceNumber = dataset.GetString(DicomTag.InstanceNumber),
ImageType = dataset.GetString(DicomTag.ImageType),
// Technical Parameters
Rows = dataset.GetString(DicomTag.Rows),
Columns = dataset.GetString(DicomTag.Columns),
BitsAllocated = dataset.GetString(DicomTag.BitsAllocated),
BitsStored = dataset.GetString(DicomTag.BitsStored),
PixelSpacing = dataset.GetString(DicomTag.PixelSpacing),
SliceThickness = dataset.GetString(DicomTag.SliceThickness),
// Equipment Information
Manufacturer = dataset.GetString(DicomTag.Manufacturer),
ManufacturerModelName = dataset.GetString(DicomTag.ManufacturerModelName),
StationName = dataset.GetString(DicomTag.StationName),
InstitutionName = dataset.GetString(DicomTag.InstitutionName),
SoftwareVersions = dataset.GetString(DicomTag.SoftwareVersions)
};
}
}
public class DicomMetadata
{
// Patient
public string PatientName { get; set; }
public string PatientID { get; set; }
public string PatientBirthDate { get; set; }
public string PatientSex { get; set; }
public string PatientAge { get; set; }
// Study
public string StudyInstanceUID { get; set; }
public string StudyDate { get; set; }
public string StudyTime { get; set; }
public string StudyDescription { get; set; }
public string AccessionNumber { get; set; }
public string ReferringPhysician { get; set; }
// Series
public string SeriesInstanceUID { get; set; }
public string Modality { get; set; }
public string SeriesDescription { get; set; }
public string SeriesNumber { get; set; }
public string BodyPartExamined { get; set; }
// Image
public string SOPInstanceUID { get; set; }
public string SOPClassUID { get; set; }
public string InstanceNumber { get; set; }
public string ImageType { get; set; }
// Technical
public string Rows { get; set; }
public string Columns { get; set; }
public string BitsAllocated { get; set; }
public string BitsStored { get; set; }
public string PixelSpacing { get; set; }
public string SliceThickness { get; set; }
// Equipment
public string Manufacturer { get; set; }
public string ManufacturerModelName { get; set; }
public string StationName { get; set; }
public string InstitutionName { get; set; }
public string SoftwareVersions { get; set; }
}
すべてのDICOMタグを閲覧
すべてのタグを完全な検査のためにDICOMファイルにリストする:
public class DicomTagBrowser
{
public List<DicomTagInfo> GetAllTags(string filePath)
{
DicomFile dicomFile = DicomFile.Open(filePath);
var tags = new List<DicomTagInfo>();
foreach (var element in dicomFile.Dataset)
{
var tagInfo = new DicomTagInfo
{
Tag = element.Tag.ToString(),
TagHex = $"({element.Tag.Group:X4},{element.Tag.Element:X4})",
Keyword = element.Tag.DictionaryEntry?.Keyword ?? "Unknown",
Name = element.Tag.DictionaryEntry?.Name ?? "Private Tag",
VR = element.ValueRepresentation.Code,
Length = element.Length,
Value = GetDisplayValue(element)
};
tags.Add(tagInfo);
}
return tags;
}
private string GetDisplayValue(DicomElement element)
{
try
{
// Handle different value representations
if (element.Length == 0)
return "(empty)";
if (element.Length > 256)
return $"(binary data, {element.Length} bytes)";
// Try to get string value
var values = element.Get<string[]>();
if (values != null && values.Length > 0)
{
return string.Join(" \\ ", values);
}
return "(unable to display)";
}
catch
{
return $"(binary data, {element.Length} bytes)";
}
}
}
public class DicomTagInfo
{
public string Tag { get; set; }
public string TagHex { get; set; }
public string Keyword { get; set; }
public string Name { get; set; }
public string VR { get; set; }
public long Length { get; set; }
public string Value { get; set; }
}
モデル特性メタデータ抽出
さまざまなイメージモダリティには、ユニークな属性があります:
public class ModalityMetadataExtractor
{
public object ExtractModalitySpecificData(string filePath)
{
DicomFile dicomFile = DicomFile.Open(filePath);
var dataset = dicomFile.Dataset;
string modality = dataset.GetString(DicomTag.Modality);
return modality switch
{
"CT" => ExtractCtMetadata(dataset),
"MR" => ExtractMrMetadata(dataset),
"CR" or "DX" => ExtractRadiographyMetadata(dataset),
"US" => ExtractUltrasoundMetadata(dataset),
"MG" => ExtractMammographyMetadata(dataset),
_ => ExtractGenericMetadata(dataset)
};
}
private CtMetadata ExtractCtMetadata(DicomDataset dataset)
{
return new CtMetadata
{
KVP = dataset.GetString(DicomTag.KVP),
XRayTubeCurrent = dataset.GetString(DicomTag.XRayTubeCurrent),
ExposureTime = dataset.GetString(DicomTag.ExposureTime),
SliceThickness = dataset.GetString(DicomTag.SliceThickness),
SpacingBetweenSlices = dataset.GetString(DicomTag.SpacingBetweenSlices),
ConvolutionKernel = dataset.GetString(DicomTag.ConvolutionKernel),
GantryTilt = dataset.GetString(DicomTag.GantryDetectorTilt),
TableHeight = dataset.GetString(DicomTag.TableHeight),
RotationDirection = dataset.GetString(DicomTag.RotationDirection),
CTDIvol = dataset.GetString(DicomTag.CTDIvol),
WindowCenter = dataset.GetString(DicomTag.WindowCenter),
WindowWidth = dataset.GetString(DicomTag.WindowWidth)
};
}
private MrMetadata ExtractMrMetadata(DicomDataset dataset)
{
return new MrMetadata
{
MagneticFieldStrength = dataset.GetString(DicomTag.MagneticFieldStrength),
SequenceName = dataset.GetString(DicomTag.SequenceName),
ScanningSequence = dataset.GetString(DicomTag.ScanningSequence),
SequenceVariant = dataset.GetString(DicomTag.SequenceVariant),
RepetitionTime = dataset.GetString(DicomTag.RepetitionTime),
EchoTime = dataset.GetString(DicomTag.EchoTime),
InversionTime = dataset.GetString(DicomTag.InversionTime),
FlipAngle = dataset.GetString(DicomTag.FlipAngle),
SliceThickness = dataset.GetString(DicomTag.SliceThickness),
EchoTrainLength = dataset.GetString(DicomTag.EchoTrainLength),
PixelBandwidth = dataset.GetString(DicomTag.PixelBandwidth),
ImagingFrequency = dataset.GetString(DicomTag.ImagingFrequency)
};
}
private RadiographyMetadata ExtractRadiographyMetadata(DicomDataset dataset)
{
return new RadiographyMetadata
{
KVP = dataset.GetString(DicomTag.KVP),
ExposureTime = dataset.GetString(DicomTag.ExposureTime),
XRayTubeCurrent = dataset.GetString(DicomTag.XRayTubeCurrent),
Exposure = dataset.GetString(DicomTag.Exposure),
ExposureIndex = dataset.GetString(DicomTag.ExposureIndex),
TargetExposureIndex = dataset.GetString(DicomTag.TargetExposureIndex),
DeviationIndex = dataset.GetString(DicomTag.DeviationIndex),
DistanceSourceToDetector = dataset.GetString(DicomTag.DistanceSourceToDetector),
DistanceSourceToPatient = dataset.GetString(DicomTag.DistanceSourceToPatient),
Grid = dataset.GetString(DicomTag.Grid),
ViewPosition = dataset.GetString(DicomTag.ViewPosition)
};
}
private UltrasoundMetadata ExtractUltrasoundMetadata(DicomDataset dataset)
{
return new UltrasoundMetadata
{
TransducerType = dataset.GetString(DicomTag.TransducerType),
TransducerFrequency = dataset.GetString(DicomTag.TransducerFrequency),
DepthOfScanField = dataset.GetString(DicomTag.DepthOfScanField),
MechanicalIndex = dataset.GetString(DicomTag.MechanicalIndex),
ThermalIndex = dataset.GetString(DicomTag.SoftTissueThermalIndex),
FrameTime = dataset.GetString(DicomTag.FrameTime),
NumberOfFrames = dataset.GetString(DicomTag.NumberOfFrames)
};
}
private MammographyMetadata ExtractMammographyMetadata(DicomDataset dataset)
{
return new MammographyMetadata
{
ViewPosition = dataset.GetString(DicomTag.ViewPosition),
ImageLaterality = dataset.GetString(DicomTag.ImageLaterality),
BreastImplantPresent = dataset.GetString(DicomTag.BreastImplantPresent),
CompressionForce = dataset.GetString(DicomTag.CompressionForce),
BodyPartThickness = dataset.GetString(DicomTag.BodyPartThickness),
AnodeTargetMaterial = dataset.GetString(DicomTag.AnodeTargetMaterial),
FilterMaterial = dataset.GetString(DicomTag.FilterMaterial),
KVP = dataset.GetString(DicomTag.KVP),
ExposureTime = dataset.GetString(DicomTag.ExposureTime),
OrganDose = dataset.GetString(DicomTag.OrganDose)
};
}
private GenericMetadata ExtractGenericMetadata(DicomDataset dataset)
{
return new GenericMetadata
{
Modality = dataset.GetString(DicomTag.Modality),
StudyDescription = dataset.GetString(DicomTag.StudyDescription),
SeriesDescription = dataset.GetString(DicomTag.SeriesDescription)
};
}
}
// Modality-specific metadata classes
public class CtMetadata
{
public string KVP { get; set; }
public string XRayTubeCurrent { get; set; }
public string ExposureTime { get; set; }
public string SliceThickness { get; set; }
public string SpacingBetweenSlices { get; set; }
public string ConvolutionKernel { get; set; }
public string GantryTilt { get; set; }
public string TableHeight { get; set; }
public string RotationDirection { get; set; }
public string CTDIvol { get; set; }
public string WindowCenter { get; set; }
public string WindowWidth { get; set; }
}
public class MrMetadata
{
public string MagneticFieldStrength { get; set; }
public string SequenceName { get; set; }
public string ScanningSequence { get; set; }
public string SequenceVariant { get; set; }
public string RepetitionTime { get; set; }
public string EchoTime { get; set; }
public string InversionTime { get; set; }
public string FlipAngle { get; set; }
public string SliceThickness { get; set; }
public string EchoTrainLength { get; set; }
public string PixelBandwidth { get; set; }
public string ImagingFrequency { get; set; }
}
public class RadiographyMetadata
{
public string KVP { get; set; }
public string ExposureTime { get; set; }
public string XRayTubeCurrent { get; set; }
public string Exposure { get; set; }
public string ExposureIndex { get; set; }
public string TargetExposureIndex { get; set; }
public string DeviationIndex { get; set; }
public string DistanceSourceToDetector { get; set; }
public string DistanceSourceToPatient { get; set; }
public string Grid { get; set; }
public string ViewPosition { get; set; }
}
public class UltrasoundMetadata
{
public string TransducerType { get; set; }
public string TransducerFrequency { get; set; }
public string DepthOfScanField { get; set; }
public string MechanicalIndex { get; set; }
public string ThermalIndex { get; set; }
public string FrameTime { get; set; }
public string NumberOfFrames { get; set; }
}
public class MammographyMetadata
{
public string ViewPosition { get; set; }
public string ImageLaterality { get; set; }
public string BreastImplantPresent { get; set; }
public string CompressionForce { get; set; }
public string BodyPartThickness { get; set; }
public string AnodeTargetMaterial { get; set; }
public string FilterMaterial { get; set; }
public string KVP { get; set; }
public string ExposureTime { get; set; }
public string OrganDose { get; set; }
}
public class GenericMetadata
{
public string Modality { get; set; }
public string StudyDescription { get; set; }
public string SeriesDescription { get; set; }
}
コンソールベースのビューアプリケーション
迅速なDICOM検査のためのコマンドラインツールを作成する:
public class DicomViewerConsole
{
public void DisplayMetadata(string filePath)
{
var viewer = new DicomMetadataViewer();
var metadata = viewer.ExtractMetadata(filePath);
Console.WriteLine("═══════════════════════════════════════════════════════════");
Console.WriteLine(" DICOM METADATA VIEWER ");
Console.WriteLine("═══════════════════════════════════════════════════════════");
Console.WriteLine($"File: {Path.GetFileName(filePath)}");
Console.WriteLine();
PrintSection("PATIENT INFORMATION");
PrintField("Patient Name", metadata.PatientName);
PrintField("Patient ID", metadata.PatientID);
PrintField("Birth Date", FormatDate(metadata.PatientBirthDate));
PrintField("Sex", metadata.PatientSex);
PrintField("Age", metadata.PatientAge);
PrintSection("STUDY INFORMATION");
PrintField("Study Date", FormatDate(metadata.StudyDate));
PrintField("Study Time", FormatTime(metadata.StudyTime));
PrintField("Description", metadata.StudyDescription);
PrintField("Accession #", metadata.AccessionNumber);
PrintField("Referring MD", metadata.ReferringPhysician);
PrintField("Study UID", metadata.StudyInstanceUID);
PrintSection("SERIES INFORMATION");
PrintField("Modality", metadata.Modality);
PrintField("Description", metadata.SeriesDescription);
PrintField("Series #", metadata.SeriesNumber);
PrintField("Body Part", metadata.BodyPartExamined);
PrintField("Series UID", metadata.SeriesInstanceUID);
PrintSection("IMAGE INFORMATION");
PrintField("Instance #", metadata.InstanceNumber);
PrintField("Image Type", metadata.ImageType);
PrintField("Dimensions", $"{metadata.Columns} x {metadata.Rows}");
PrintField("Bits Stored", metadata.BitsStored);
PrintField("Pixel Spacing", metadata.PixelSpacing);
PrintField("SOP Instance", metadata.SOPInstanceUID);
PrintSection("EQUIPMENT");
PrintField("Manufacturer", metadata.Manufacturer);
PrintField("Model", metadata.ManufacturerModelName);
PrintField("Station", metadata.StationName);
PrintField("Institution", metadata.InstitutionName);
PrintField("Software", metadata.SoftwareVersions);
Console.WriteLine("═══════════════════════════════════════════════════════════");
}
private void PrintSection(string title)
{
Console.WriteLine();
Console.WriteLine($"─── {title} ───");
}
private void PrintField(string label, string value)
{
string displayValue = string.IsNullOrEmpty(value) ? "(not specified)" : value;
Console.WriteLine($" {label,-15}: {displayValue}");
}
private string FormatDate(string dicomDate)
{
if (string.IsNullOrEmpty(dicomDate) || dicomDate.Length != 8)
return dicomDate;
return $"{dicomDate.Substring(0, 4)}-{dicomDate.Substring(4, 2)}-{dicomDate.Substring(6, 2)}";
}
private string FormatTime(string dicomTime)
{
if (string.IsNullOrEmpty(dicomTime) || dicomTime.Length < 6)
return dicomTime;
return $"{dicomTime.Substring(0, 2)}:{dicomTime.Substring(2, 2)}:{dicomTime.Substring(4, 2)}";
}
}
Web API for メタデータリリーバル
メタデータへのアクセスのためのRESTエンドポイントを構築する:
[ApiController]
[Route("api/[controller]")]
public class DicomMetadataController : ControllerBase
{
private readonly string _uploadPath = Path.Combine(Path.GetTempPath(), "dicom_uploads");
public DicomMetadataController()
{
Directory.CreateDirectory(_uploadPath);
}
[HttpPost("upload")]
public async Task<IActionResult> UploadAndExtract(IFormFile file)
{
if (file == null || file.Length == 0)
return BadRequest("No file provided");
var filePath = Path.Combine(_uploadPath, $"{Guid.NewGuid()}.dcm");
try
{
using (var stream = new FileStream(filePath, FileMode.Create))
{
await file.CopyToAsync(stream);
}
var viewer = new DicomMetadataViewer();
var metadata = viewer.ExtractMetadata(filePath);
return Ok(metadata);
}
finally
{
if (System.IO.File.Exists(filePath))
System.IO.File.Delete(filePath);
}
}
[HttpPost("tags")]
public async Task<IActionResult> GetAllTags(IFormFile file)
{
if (file == null || file.Length == 0)
return BadRequest("No file provided");
var filePath = Path.Combine(_uploadPath, $"{Guid.NewGuid()}.dcm");
try
{
using (var stream = new FileStream(filePath, FileMode.Create))
{
await file.CopyToAsync(stream);
}
var browser = new DicomTagBrowser();
var tags = browser.GetAllTags(filePath);
return Ok(tags);
}
finally
{
if (System.IO.File.Exists(filePath))
System.IO.File.Delete(filePath);
}
}
[HttpPost("modality-specific")]
public async Task<IActionResult> GetModalityMetadata(IFormFile file)
{
if (file == null || file.Length == 0)
return BadRequest("No file provided");
var filePath = Path.Combine(_uploadPath, $"{Guid.NewGuid()}.dcm");
try
{
using (var stream = new FileStream(filePath, FileMode.Create))
{
await file.CopyToAsync(stream);
}
var extractor = new ModalityMetadataExtractor();
var data = extractor.ExtractModalitySpecificData(filePath);
return Ok(data);
}
finally
{
if (System.IO.File.Exists(filePath))
System.IO.File.Delete(filePath);
}
}
}
メタデータ輸出レポート
さまざまな形式でメタデータレポートを生成する:
public class MetadataReportGenerator
{
public void GenerateCsvReport(string dicomDirectory, string outputPath)
{
var viewer = new DicomMetadataViewer();
var records = new List<string>();
// Header
records.Add("FileName,PatientID,PatientName,StudyDate,Modality,SeriesDescription,Rows,Columns");
var files = Directory.GetFiles(dicomDirectory, "*.dcm", SearchOption.AllDirectories);
foreach (var file in files)
{
try
{
var metadata = viewer.ExtractMetadata(file);
var record = string.Join(",",
EscapeCsv(Path.GetFileName(file)),
EscapeCsv(metadata.PatientID),
EscapeCsv(metadata.PatientName),
EscapeCsv(metadata.StudyDate),
EscapeCsv(metadata.Modality),
EscapeCsv(metadata.SeriesDescription),
metadata.Rows ?? "",
metadata.Columns ?? "");
records.Add(record);
}
catch (Exception ex)
{
Console.WriteLine($"Error processing {file}: {ex.Message}");
}
}
File.WriteAllLines(outputPath, records);
}
public void GenerateJsonReport(string dicomDirectory, string outputPath)
{
var viewer = new DicomMetadataViewer();
var metadataList = new List<object>();
var files = Directory.GetFiles(dicomDirectory, "*.dcm", SearchOption.AllDirectories);
foreach (var file in files)
{
try
{
var metadata = viewer.ExtractMetadata(file);
metadataList.Add(new
{
FileName = Path.GetFileName(file),
Metadata = metadata
});
}
catch (Exception ex)
{
metadataList.Add(new
{
FileName = Path.GetFileName(file),
Error = ex.Message
});
}
}
var json = JsonSerializer.Serialize(metadataList, new JsonSerializerOptions
{
WriteIndented = true
});
File.WriteAllText(outputPath, json);
}
private string EscapeCsv(string value)
{
if (string.IsNullOrEmpty(value))
return "";
if (value.Contains(",") || value.Contains("\"") || value.Contains("\n"))
{
return $"\"{value.Replace("\"", "\"\"")}\"";
}
return value;
}
}
使用例
class Program
{
static void Main(string[] args)
{
// Activate license
Metered metered = new Metered();
metered.SetMeteredKey("your-public-key", "your-private-key");
string dicomFile = @"C:\DICOM\sample.dcm";
// Console viewer
var consoleViewer = new DicomViewerConsole();
consoleViewer.DisplayMetadata(dicomFile);
// Browse all tags
var browser = new DicomTagBrowser();
var tags = browser.GetAllTags(dicomFile);
Console.WriteLine($"\nTotal tags: {tags.Count}");
// Generate report for directory
var reportGenerator = new MetadataReportGenerator();
reportGenerator.GenerateCsvReport(@"C:\DICOM\Studies", @"C:\Reports\metadata.csv");
}
}
結論
DICOMメタデータビューヤーの構築は、医療イメージの開発に不可欠な能力を提供します. 迅速なコマンドラインインスペクター、統合のためのWeb API、またはバッチレポートツールを必要としているかどうかにかかわらず、Aspose.Medical for .NETはDICOの特性を抽出し分析するための基礎を備えています. これらのテクニックはトラブル解決、品質保証、および医療画像アプリケーションの建設に有益です。
DICOMファイルの作業に関する詳細については、こちらをご覧ください。 メディカル・ドキュメンタリー.