European Forearm Phantom

The standard for quality control in peripheral bone mineral densitometry by DXA and QCT.

 

QRM-EFP, a phantom consisting of water- and bone-equivalent solid materials was devised to test peripheral bone densitometry systems. A prime design consideration of the forearm phantom was to use the same material as is used for the European Spine Phantom QRM-ESP-04 . This not only allows for the comparision of trabecular bone examinations at different locations and different machines, but also to compare axial with peripheral bone measurements. 
A circular cross section with a diameter of 60 mm was chosen, with the sides flattened by 10 mm to model the forearm. The inserts simulate trabecular bone and provide the basis for linearity checks of QCT systems. Density and thickness of the simulated compact bone is selected such that the phantom can be used to calibrate DXA and SPA machines as well. 
The phantom should allow one to test reproducibility and accuracy of machines, both in clinical installations and at manufacturers’ sites. 

The following quantities can be determined: 
(i) bone area in cm², 
(ii) thickness of cortical bone in mm, 
(iii) trabecular and cortical mineral density in g/cm³, 
(iv) bone mineral content (BMC) in g/cm, 
(v) bone mineral area density (BMD) in g/cm². 

The three inserts of the phantom simulating large, medium and small bone have diameters of 28 mm, 21 mm and 14 mm, respectively. The calcium hydroxyapatite (HA) density of the simulated trabecular bone was selected according to the densities used in the European Spine Phantom QRM-ESP-04, namely 200, 100 and 50 mg HA/cm³. 
1.2 mm was selected as the thickness of the cortical bone for section I + III and 0.6mm for section II. Its HA density was chosen as 800 mg HA/cm³. 
In addition to the three inserts a fourth insert was added to also enable valida-tions of SPA (single photon absorptiometry) systems. 
Quality control with CT guarantes a homogeneously distributed trabecular bone density with an average that deviates less than 1mg/cm³ from linearity.

Specifications

Base material:	water-equivalent resin
Phantom cross section:	60 mm x 40 mm
Phantom length:	100 mm
Phantom weight:	140 g
Cortical bone:	800 mg HA/cm3
Trabecular bone:
Section I:	200 mg HA/cm3
Section II:	100 mg HA/cm3
Section III:	50 mg HA/cm3
Section IV to VI:	water-equivalent resin

 

Forearm Phantom

A Phantom for Quantitative Computed Tomography (QCT) measurements of the forearm to calibrate CT values to Bone Mineral Density (BMD).

 

The QRM-Forearm-Phantom was developed for calibrating CT values to BMD. Its shape is optimized to the anatomy of an adult forearm. It is placed between the forearm and the CT coach pet directly. 
The phantom consists of two solid cylindrical rods, of water-equivalent and boneequivalent material, respectively.

Specifications

Base material:	tissue-equivalent resin
Phantom cross section:	70 x 25 mm2
Phantom length:	150 mm
Phantom weight:	225 g
Bone eqv insert specified:	200 mg HA/cm3
Water equivalent insert:	0 HU (80 - 140 kV)

 

Hip Calibration Phantom

A Phantom for Computed Tomography (CT) measurements of the hip-region. Different inserts, e.g. titan implants are available.

 

The Hip-Phantom comprises a water-equivalent phantom body, made from CTWater®, and two cylinders with a specified bone mineral density of 800 (cortical bone) and 100 mg (cancellous bone) hydroxyapatite (HA) per cm³ respectively.

The bone-simulating cylinders have an outer diameter of 30 mm and a wall thickness of 5 mm (cortical bone), the inner part is 20 mm in diameter (spongious/cancellous bone) and is available in different HA concentrations (typically 100 mg HA / cm³). 


The finished phantom will be scanned to confirm the quality of all manufacturing steps and the homogeneity and water equivalence of the phantom body. 
All CT measurements are performed on a state of the art CT scanners

Specifications

Mineral Density:	800.0 and 100.0 mg HA/cm3 ±1.5 %
Mechanical Dimensions:	Outer diameter: 30.0 mm ±0.1 mm  Wall thickness: 5.0 mm ±;0.1 mm
Water-equivalent phantom body:
Average CT number at 80 to 140 kV tube voltage:	0 HU ±5 HU (max.), typically ±3 HU
Mechanical Dimensions:	Cross section: 360 mm x 160 mm Thickness: 60 mm