NUCLEAR MEDICINE IMAGING IN SPONDYLOARTHROPATHIES:FROM SACROILIAC JOINT UPTAKE RATIO TO HYBRID IMAGING

John T. Koutsikos, MD, PhDDepartment of Nuclear Medicine401 General Military Hospital,Athens, Greece

INTRODUCTION

Spondylarthropathies (SpA) as a group have seronegative,

inflammatory arthritis with a relationship to HLA B27, characterized

by involvement of the spine, peripheral arthtitis and enthesitis.

Represent a variety of diagnoses, including ankylosing spondylitis

(AS), reactive arthritis, psoriasic arthritis (PsA), and enteropathic

arthritis.

It is now more important than ever to diagnose and treat SpA early,

since new therapeutic agents have yielded tremendous responses

not only in advanced disease but also in the early stages of the

disease.

IMAGING IImaging of the sacroiliac joints (SIJ) has an important role in the

diagnosis, classification and monitoring of patients with SpA.

Conventional radiography was given an outstanding role in the

development of classification New York (NY) criteria in 1961 and

modified NY criteria in 1984.

However, radiographic sacroiliitis reflects structural changes which

may appear late in the disease process at least in a subset of patients.

It has low specificity especially for patients at the early stages of the

disease.

To enable earlier diagnosis, highly reliable and sensitive imaging

techniques are needed.

IMAGING II

Magnetic resonance imaging (MRI) is used as a sensitive imaging

modality for the detection of sacroiliitis in early SpA.

MRI detects (early) inflammation such as bone marrow edema/osteitis,

synovitis, enthesitis and capsulitis associated with SpA

MRI has become a pivotal imaging tool for early diagnosis of axial SpA

(recently included as a major criterion in the ASAS classification

criteria)

SCINTIGRAPHY I

Four decades ago several reports about the diagnostic role of

scintigraphy to detect sacroiliitis were promising

SCINTIGRAPHY II

Four decades ago several reports about the diagnostic role of

scintigraphy to detect sacroiliitis were promising

Bone scintigraphy was the method of choice and quantification of SIJ

index has been used as a diagnostic procedure to detect early

sacroiliitis.

SCINTIGRAPHY IIIBone scintigraphy was the method of choice and quantification of SIJ

index has been used as a diagnostic procedure to detect early

sacroiliitis.

However, data about the diagnostic value of bone scan to detect

acute inflammatory changes in the SIJ are conflicting and many

studies suggest that scintigraphy of the SIJ is at most of limited

diagnostic value for the diagnosis of established SpA, including the

early diagnosis of probable/suspected sacroiliitis.

BONE SPECT

Single photon emission computed tomography (SPECT) of the bone,

compared with planar scintigraphy increases image contrast and

improves lesion detection and localization.

Studies have documented the unique diagnostic information provided

by SPECT in patients with back pain.

In several studies bone SPECT appears to be an excellent diagnostic

tool for active sacroiliitis.

2009 SNM Annual Congress

RADIOGRAPHIC SUSPICIOUS CHANGES IN THE SACROILIAC JOINTS: THE ROLE OF BONE SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY (SPECT) SCINTIGRAPHY

T. Pipikos1, J. Koutsikos1, S. Bakalis1, S. Episkopopoulou1, K. Athanasiou1, G. Koniaris1, D.

Kassimos2; 1 Nuclear Medicine dept., 2 Rheumatology dept.,401 General Military Hospital, ATHENS, GREECE

AIM To evaluate the role of bone single photon emission computed tomography (SPECT) scintigraphy in the detection of sacroiliitis in patients with SpA and suspicious changes of sacroiliitis on X-ray.

X-ray, MRI, and SPECT of the sacroiliac joints of 46 SpA patients (41 males, 5 females, mean age 28.2 y.o.) were evaluated retrospectively.

Fourteen patients were classified as grade 1

MRI detected features of sacroiliitis in 10/14 patients (71%)

SPECT FINDINGS

SPECT was (+)ve in all 10 MRI identified pts, as well as in

one more male with increased CRP and ECR.

In a 2-year follow up period, ankylosing spondylitis was

established for this patient.

(-)VE SPECT

(+)VE SPECT

SCINTIGRAPHY II

Other radiopharmaceuticals such as Ga-67, radiolabelled leucocytes, In-111

chloride, 99mTc labelled liposomes were demonstrated to accumulate in

inflamed area in arthritis

However these agents have not been used in routine clinical practice.

99mTc labeled nonspecific polyclonal human immunoglobulin (HIG)

accumulates in infection and sterile inflammatory processes. HIG being a

nonspecific marker of inflammation and infection may help to detect active

inflammation in SpA.

HIG SCINTIGRAPHY

HIG SCINTIGAPHY

EANM Annual Congress 2007

PET-CT

Inflammation tracersglucose analogue F-18 FDG

macrophage tracer C-11 PK11195

Bone tracerF-18 Fluoride