Authorised Indian Distributor
Saxsons Group
New Delhi, India · Since 1997
Delta4 Phantom+Patient QA System
The fastest 4D verification system for IMRT, VMAT, SRS, Radixact and TomoTherapy. Dual orthogonal detector planes give you per-fraction, per-beam, per-control-point confidence before every treatment.
Key Features
- Simultaneous 4D dose in two orthogonal planes (coronal + sagittal)
- Verifies IMRT, VMAT, Halcyon, SRS, SBRT, Radixact and TomoTherapy
- Single system for patient QA and daily machine QA
- Wireless Wi-Fi — no cables required during measurement
- Battery-operated (>4 h Li-ion) for free positioning
All Features
- Simultaneous 4D dose in two orthogonal planes (coronal + sagittal)
- Verifies IMRT, VMAT, Halcyon, SRS, SBRT, Radixact and TomoTherapy
- Single system for patient QA and daily machine QA
- Wireless Wi-Fi — no cables required during measurement
- Battery-operated (>4 h Li-ion) for free positioning
- No external trigger — fully autonomous acquisition
- Automatic temperature correction; no warm-up drift
- p-type silicon diodes: isotropic, FFF-beam compatible
- Detector stability: <0.1%/kGy (typ. 0.04%/kGy at 6 MV)
- DICOM RT plan, dose and structure import from any TPS
- Per-fraction, per-beam, per-control-point analysis
- Fast trolley delivery — no manual lifting needed
Technical Specifications
| Detector type | p-type silicon (p-Si) disc diode |
| Total detectors | 1,069 |
| Detector planes | Coronal and sagittal (dual orthogonal) |
| Detector dimensions | 1 mm diameter × 0.05 mm thick |
| Active volume | 0.04 mm³ |
| Resolution — central | 5 mm (6 × 6 cm² isocentric area) |
| Resolution — outer | 10 mm |
| Max field size | 20 × 38 cm² (merged); 20 × 20 cm² (single) |
| Phantom material | PMMA (optional Plastic Water DT) |
| Phantom diameter | 22 cm |
| Phantom length | 40 cm (total system 71 cm) |
| Total weight | 27 kg |
| Communication | Wi-Fi (wired Ethernet option available) |
| Power | Rechargeable Li-ion; >4 h per charge |
| Absolute calibration | Required; IC verification optional |
| TPS compatibility | Any TPS with DICOM RT (plan, dose, structures) |
| Modalities | Photon — with and without flattening filter (FFF) |
| Detector stability | <0.1%/kGy; typically 0.04%/kGy at 6 MV |
| Setup time | Seconds (trolley-mounted) |
Linac Compatibility
Varian
TrueBeam, Halcyon, Edge, Clinac
Elekta
Versa HD, Infinity, Synergy
Accuray
Radixact, TomoTherapy HDA, CyberKnife
ViewRay
MRIdian Linac
Siemens
Artiste, Oncor
Brainlab
Vero (with DICOM RT)
Any TPS with DICOM RT (plan, dose, structures) export is supported — including Pinnacle, Eclipse, Monaco, RayStation, Tomotherapy Hi-Art.
Delta4 Software Ecosystem
Core verification software included. Optional modules extend to machine QA, anatomy dose mapping, and statistical trending.
Delta4 Phantom+ Software
Core 4D verification suite. Instant pass/fail, gamma index, DTA, profile, isodose, per-control-point analysis. Customisable reporting. 21 CFR Part 11 audit trail.
Delta4 Machine QA
Daily machine QA: output constancy, flatness, symmetry, MLC position, couch rotation. One detector, two workflows.
Delta4 DVH Anatomy
Maps measured 4D dose onto patient CT anatomy. Delivers dose-volume histogram comparison for biological impact assessment.
Delta4 Statistics
Longitudinal QA trending across patients and machines. Identifies drift before it becomes a clinical issue. Network-compatible database.
Delta4 HexaMotion
6-DOF motion platform for moving-target verification — 4D SBRT and gating QA. Mounts directly under the phantom.
Clinical Applications
One system — the full scope of modern radiotherapy QA
Pre-treatment patient QA
Verify each IMRT and VMAT plan before first fraction. Complete gamma analysis and report in under 20 minutes.
SRS / SRBT verification
High-resolution 5 mm central detector grid meets sub-millimetre SRS spatial requirements with small-field corrections.
Radixact & TomoTherapy QA
Helical delivery QA — axial resolution expandable via merged measurement sets. Full rotational dose captured.
MR-Linac plan verification
Compatible with ViewRay MRIdian workflows via DICOM RT import and standard calibration chain.
Daily & monthly machine QA
Delta4 Machine QA module turns the same phantom into a linac QA tool — output, flatness, MLC leaf bank tests.
Moving-target / gating QA
Pair with Delta4 HexaMotion for 6-DOF motion, gated delivery verification and 4D SBRT dose reconstruction.
Why Delta4 Phantom+?
Competing systems measure in one plane. Delta4 Phantom+ captures the full 4D dose distribution simultaneously — coronal and sagittal — giving a complete volumetric picture without stitching or sequential acquisitions.
Add the Delta4 Machine QA software module and the same phantom handles daily output constancy, flatness, symmetry and MLC tests — reducing capital spend without switching equipment.
From trolley placement to signed-off PDF report in under 20 minutes. No cables, no warm-up, no manual lifting. The wireless Li-ion system is ready the moment you wheel it into the treatment room.
Delta4 Phantom+
More for this product
Each card opens a focused post for a specific specialty — peer-reviewed evidence and clinical workflow, written for the persona you select.
For Medical Physicist
Sensitivity to introduced plan errors
At what magnitude of MLC, gantry, collimator or MU error does the Delta4 gamma passing rate cross the 95 % action threshold? Per Udee 2024, J Med Phys.
Read thisMedical Physicist50 nGy per-pulse integration — why it matters for FFF and FLASH
Ion chambers under-respond and many diodes drift at high dose-per-pulse. What changes when the detector integrates one pulse at a time at 50 nGy resolution?
Read thisMedical PhysicistOne phantom — TG-218 patient QA and TG-142 machine QA
Departments routinely run separate equipment for patient-specific QA and routine machine QA. What changes when the same 1,069-detector array runs both workflows under one software ecosystem?
Read thisFAQ
IMRT / VMAT patient QA — questions we hear from Indian medical-physicist teams
Why patient-specific QA is a TG-218 requirement, what 2D arrays miss on VMAT arcs, how the 4D detector geometry catches gantry-angle-dependent errors, and how Delta4 Phantom+ is supplied across India.
Q.Why is patient-specific QA needed at all for IMRT and VMAT plans?
IMRT and VMAT plans use hundreds of small, dynamically-shaped fields whose combined dose distribution comes together only at the patient isocentre. The TPS calculates the intended distribution, but the actual delivered distribution depends on MLC leaf response, gantry-speed / dose-rate synchronisation, beam symmetry and a dozen other machine-side variables. AAPM TG-218 mandates pre-treatment patient-specific QA — an independent measurement that verifies the linac actually delivers what the plan calculated, before the patient is treated.
Q.What limitation of 2D detector arrays does Delta4 Phantom+ address?
Planar 2D arrays measure dose in a single coronal or sagittal plane, so an error that only reveals itself at 45° gantry — a leaf that lags on the return sweep, a jaw that mis-tracks in a VMAT arc — can pass the 2D gamma analysis but fail the patient. Delta4 Phantom+ resolves the delivered dose in 4D (three spatial dimensions plus time) using 1 069 p-Si detectors arranged in two orthogonal planes, so gantry-angle-dependent errors are visible in the gamma map, not masked by planar averaging.
Q.Does Delta4 Phantom+ work on TomoTherapy and Radixact deliveries?
Yes. Delta4 Phantom+ was designed for helical-delivery platforms as well as C-arm linacs — TomoTherapy, Accuray Radixact, Varian TrueBeam / Halcyon / Ethos and Elekta Versa HD / Infinity. The 5 mm isocentre resolution reads the small-field sub-arc pattern of a Radixact tomodelivery without spatial averaging.
Q.How does Delta4 Phantom+ fit AAPM TG-218 pass/fail workflows?
TG-218 sets action-level and tolerance-level 3 %/2 mm and 2 %/2 mm gamma criteria for IMRT/VMAT patient QA. Delta4 Phantom+ software runs the gamma analysis in both criteria automatically, reports the per-plan pass/fail against the TG-218 threshold, and stores the result in the per-patient QA archive that AERB and NABH inspection expect to see.
Q.How is Delta4 Phantom+ supplied and supported in India?
Delta4 Phantom+ is distributed across India by Saxsons Group under SKU RT-005. The package covers the phantom, dosimetry electronics, analysis software, commissioning training against the department's existing TPS beam data, and ongoing applications support — the department signs one PO and can start running pre-treatment IMRT/VMAT QA within the commissioning cycle.
Delta4 Phantom+ supplier in India — Saxsons Group
Saxsons Group has supplied radiotherapy equipment to over 1,000 Indian hospitals since 1988. Every consignment of Delta4 Phantom+ ships with cold-chain logistics, AERB import documentation, CDSCO registration references and a Certificate of Analysis delivered before dispatch — the paperwork your radiation-safety and procurement teams need, pre-assembled.
- Nationwide delivery footprint — every metro and tier-2 city in India, scheduled to your treatment / procedure calendar.
- AERB & CDSCO documentation — import licence, radiation-safety paperwork and RSO briefing pre-assembled for the audit file.
- 40+ years in Indian oncology — long-standing supply relationships with AIIMS, Tata Memorial, and hundreds of tertiary-care centres.
- Single point of accountability — one purchase order, one delivery contact, one after-sales team across the whole product family.
Also supplied by Saxsons Group across India
Ready to bring Delta4 to your department?
Contact Saxsons Group for pricing, demo scheduling, AERB import documentation and installation support.