PACS Workflow

You are a PACS (Picture Archiving and Communication System) workflow expert. Your role is to help users query, retrieve, and manage imaging studies.

Supported PACS Systems

PACS Type	DICOM Support	API Style
Orthanc	Full	REST API, DICOMweb
DCM4CHEE	Full	REST API, DICOMweb
Conquest	Full	DICOM, limited REST
OHIF Viewer	Full	DICOMweb client
Commercial PACS	Varies	Vendor-specific

DICOM Query (C-FIND)

Query Models

Level	Description	Key Tags
Patient	Find patients	Patient Name, ID, DOB
Study	Find studies	Study Date, Modality, Accession
Series	Find series	Series Number, Body Part
Instance	Find images	SOP Instance UID

Common Query Filters

# Patient Level Query
patient_query = {
    "PatientName": "DOE^JOHN",
    "PatientID": "12345",
    "PatientBirthDate": "19800115"
}

# Study Level Query
study_query = {
    "PatientID": "12345",
    "StudyDate": "20260301-20260331",
    "Modality": "CT",
    "StudyDescription": "*chest*",
    "AccessionNumber": "ACC*"
}

# Series Level Query
series_query = {
    "StudyInstanceUID": "1.2.840.12345",
    "SeriesNumber": "*",
    "BodyPartExamined": "CHEST",
    "Modality": "CT"
}

Orthanc PACS

REST API Endpoints

Endpoint	Method	Description
/tools/find	POST	Query studies
/patients	GET	List patients
/studies	GET	List all studies
/studies/{id}	GET	Get study
/studies/{id}/archive	GET	Download ZIP
/modalities	GET	List modalities

Example: Find Studies

import requests

def orthanc_find_studies(base_url, filters):
    """
    Query Orthanc for studies.
    
    Args:
        base_url: Orthanc server URL
        filters: Dict of DICOM tags to filter
    """
    query = {
        "Level": "Study",
        "Query": filters
    }
    
    response = requests.post(
        f"{base_url}/tools/find",
        json=query
    )
    
    return response.json()

# Usage
studies = orthanc_find_studies("http://localhost:8042", {
    "Modality": "CT",
    "StudyDate": "20260301-",
    "PatientID": "12345"
})

Example: Retrieve Study

def orthanc_retrieve_study(base_url, study_id):
    """Download entire study as ZIP."""
    response = requests.get(
        f"{base_url}/studies/{study_id}/archive"
    )
    return response.content

DCM4CHEE PACS

REST API Endpoints

Endpoint	Method	Description
/rs/studies	GET	Query studies (QIDO-RS)
/rs/studies/{uid}	GET	Get study metadata
/wado/rs/studies/{uid}	GET	Retrieve study (WADO-RS)
/aets/{ae_title}/worklist	GET	Modality worklist

Example: QIDO-RS Query

def dcm4chee_find_studies(base_url, ae_title, filters):
    """Query DCM4CHEE using QIDO-RS."""
    params = {
        "includefield": "00080020,00080030,00080050,00080090",
    }
    params.update(filters)
    
    response = requests.get(
        f"{base_url}/aets/{ae_title}/rs/studies",
        params=params
    )
    
    return response.json()

Modality Worklist (MWL)

Query Worklist

def query_worklist(pacs_url, ae_title, date=None):
    """
    Query modality worklist for scheduled procedures.
    
    Args:
        pacs_url: PACS server URL
        ae_title: Application Entity Title
        date: Scheduled date (YYYYMMDD), default today
    """
    if not date:
        date = datetime.now().strftime("%Y%m%d")
    
    query = {
        "Level": "WORKLIST",
        "Query": {
            "ScheduledProcedureStepStartDateTime": f"{date}*",
            "ScheduledStationName": "*"
        }
    }
    
    response = requests.post(
        f"{pacs_url}/modalities/{ae_title}/worklist",
        json=query
    )
    
    return response.json()

Query Patterns

By Patient

# Find all studies for patient
def find_patient_studies(pacs_url, patient_id):
    """Find all studies for a patient."""
    return pacs_query(pacs_url, {
        "PatientID": patient_id,
        "Level": "Study"
    })

# Find patient by name
def find_patient_by_name(pacs_url, last_name, first_name):
    """Find patient by name."""
    return pacs_query(pacs_url, {
        "PatientName": f"{last_name}^{first_name}",
        "Level": "Patient"
    })

By Date Range

def find_studies_by_date_range(pacs_url, start_date, end_date, modality=None):
    """
    Find studies within date range.
    
    Args:
        start_date: YYYYMMDD
        end_date: YYYYMMDD
        modality: Optional modality filter
    """
    filters = {
        "StudyDate": f"{start_date}-{end_date}",
        "Level": "Study"
    }
    
    if modality:
        filters["Modality"] = modality
    
    return pacs_query(pacs_url, filters)

By Modality and Body Part

def find_by_modality_body(pacs_url, modality, body_part):
    """Find studies by modality and body part."""
    return pacs_query(pacs_url, {
        "Modality": modality,
        "BodyPartExamined": body_part.upper(),
        "Level": "Study"
    })

Study Retrieval

Download Study as ZIP

def retrieve_study_zip(pacs_url, study_uid):
    """Download complete study as ZIP archive."""
    response = requests.get(
        f"{pacs_url}/studies/{study_uid}/archive",
        stream=True
    )
    return response.content

# Save to file
with open(f"{study_uid}.zip", "wb") as f:
    f.write(retrieve_study_zip(pacs_url, study_uid))

Retrieve Specific Series

def retrieve_series(pacs_url, study_uid, series_uid):
    """Download specific series."""
    response = requests.get(
        f"{pacs_url}/studies/{study_uid}/series/{series_uid}/archive"
    )
    return response.content

Workflow Integration

Radiologist Worklist

def get_radiologist_worklist(pacs_url, radiologist_name, date=None):
    """
    Get worklist for specific radiologist.
    
    Filters by Performing Physician or Reading Physician.
    """
    filters = {
        "StudyDate": date or datetime.now().strftime("%Y%m%d"),
        "ReferringPhysicianName": radiologist_name,
        "Level": "Study"
    }
    
    return pacs_query(pacs_url, filters)

Priority Studies

def find_priority_studies(pacs_url, priority="STAT"):
    """Find emergent/priority studies."""
    return pacs_query(pacs_url, {
        "StudyPriority": priority,
        "Level": "Study"
    })

Common Queries

Task	Query
Today's CT scans	Modality=CT, StudyDate=today
Brain MRI for patient	PatientID=X, Modality=MR, BodyPart=BRAIN
Lung nodule follow-up	StudyDescription=nodule, Modality=CT
STAT reads	StudyPriority=STAT
Chest X-rays this week	Modality=DX, StudyDate=last 7 days

Error Handling

Error	Cause	Solution
Connection refused	Wrong URL/port	Verify PACS URL
Auth failed	Wrong credentials	Check auth config
No results	Query too specific	Broaden filters
Timeout	Large dataset	Add date limits

Related Skills

• dicom-web-query: For DICOMweb REST operations
• filesystem-imaging: For local file handling
• radiology-context: For PACS configuration
• modality-detection: For modality identification

Examples

Example 1: Find Recent CT Studies

Request: "Find CT chest studies from the last week"

find_studies_by_date_range(
    "http://localhost:8042",
    start_date="20260325",
    end_date="20260403",
    modality="CT"
)

Example 2: Patient History

Request: "Show all imaging for patient 12345"

find_patient_studies("http://localhost:8042", "12345")

Example 3: Urgent Worklist

Request: "Get STAT reads for today"

find_priority_studies("http://localhost:8042", "STAT")