Osteoradionecrosis is a serious complication of radiotherapy to the jaws that results in chronic non-healing of irradiated bone. Radiotherapy damages the vasculature of bone tissue, impairing healing. Risk factors include higher radiation dose, larger irradiated mandibular volume, and dental extractions within the radiation field. Symptoms include pain, exposed bone, and pathologic fracture. Treatment involves controlling infection with antibiotics and debridement. Hyperbaric oxygen therapy increases healing by enhancing angiogenesis and is often used as an adjuvant. Reconstruction of large defects from osteoradionecrosis requires free tissue transfer due to poor healing in irradiated tissue.

1. OSTEORADIONECR
OSIS AND
HYPERBARIC
OXYGEN THERAPY
Guided by :
Dr G.K Thapliyal
Dr Ambika Luthra
Presented by :
Dr Meghali Diwaker

2. “The treatment of head and neck cancer remains a challenge. Despite
advances in surgical reconstructive techniques, about two thirds of
patients will require adjuvant therapy in the form of radiotherapy or
chemoradiotherapy to improve locoregional control.
The initial effects of radiotherapy to the oral tissues such as
mucositis and loss of taste are troublesome but short lived
resolving within a few weeks. Xerostomia may be more persistent
but can be managed with supportive therapy such as sialogogues
and artificial saliva. Osteoradionecrosis is the long term and most
serious side effect of radiotherapy.

3. What is osteoradionecrosis
Earlier was considered as an infection initiated by injury to irradiated
bone.
The first report on osteoradionecrosis of the mandible was published
in 1922 by Regaud.
3
Chronic, non-healing wound caused by hypoxia,
hypocellularity and hypovascularity of irradiated tissue.
(Marx)

4. EFFECTS OF IRRADIATION ON TISSUES
The
effects
of
radiation
depends
on :
Quality of radiation
Quantity of radiation
Size of the portals
Location and extent of the lesion
Condition of the teeth and periodontium

5. Effect on Soft Tissues
‐ Swelling Edema Exudation Ulceration necrosis
5

6. EFFECT ON BONE
‐ Effects of irradiation are due to the production of vascular
disturbances which result in decreased blood supply to the tumor.
Bone is similarly involved by a decrease in its circulation. (EWING)
‐ lack of osteoblasts along the inner surface of the periosteum.
‐ M’cCrorie - theorized that the lethal dose of irradiation was less for
osteoblasts than for osteoclasts allowing unopposed osteolysis.
‐ Endarteritis and periarteritis are constant findings.
David S Topazian – Prevention of osteoradionecrosis of the jaws, OS OM OP May 1959

7. Effect on teeth
‐ Sensitivity to heat, cold, and sweets
‐ A diminution in salivary secretion.
‐ Associated with caries like lesions at the cementoenamel
junction
7

8. ‐ Mandible is affected more commonly than the maxilla.
‐ Absence of dense cortical plates and the presence of
a more extensive vascular network in the maxilla
lessen its likelihood of radiation necrosis effects
compared with the mandible.
8
Ewing" described a loss of osteoblasts and
diminished vascularity in irradiated bone
resulting from endarteritis and perioarteritis.
Mcl.ennal found that the canaliculi and lacunae
were disrupted with a loss of lamellar bone
structure.
MacLennanl
83 % of the cases affect the mandible,
chiefly because its main blood supply is
composed of one large vessel.

9. 9
ORN
RADIATION
TRAUMAINFECTIONS

10. ‐ Radiation to the jaws in excesss of 50 Gy kills bone cells
‐ Progressive obliterative arteritis
‐ Vessels are affected
‐ Aseptic necrosis of the portion of the bone directly in the beam
of radiation
‐ Effective response to infection is diminished greatly
10
The viable radiation damaged cells are not replaced by the cells of
the same type, resulting in less cellular, more extra cellular
elements such as collagen. These tissues are susceptible to

11. Clinical presentation
 Pain
 Evidence of exposed bone with grey to
yellow colour
 Trismus
 Fetid breath
 Elevated temperature
 Intraoral and extraoral fistulae
 Pathological fractures may be present
 Tissues surrounding the bone may be indurated or
ulcerated
11

12. Radiological considerations
‐ Radiation damage to the mandible can lead to loss of bone mass with
resorption of the osseous trabeculae. On OPG, it is seen initially as
rarefaction of the affected bone, or later, as lytic areas within the
mandible.
‐ Sequestrum, which is defined as “dead bone”, may be seen as a
radiodense area amidst the affected rarefied portion of the mandible
‐ Progression of the disease can lead to pathological fracture in severe
cases, which is seen as a cortical break.
12

13. 13

14. 14

15. 15

16. Radiological differentiation of mandibular
ORN and tumour recurrence
‐ Tumour recurrence also commonly presents as
osteolytic
‐ lesions with associated soft-tissue mass. It may be
associated with pathological fracture.
‐ Tumour recurrence is usually encountered within 2
years of treatment of the primary tumour; whereas the
time to presentation of ORN can be variable (early or
late ORN).
16

17. Diffusion-weighted imaging
‐ DWI is a technique that capitalizes of the diffusion properties of
water protons in a given tissue.
‐ As tumour recurrence comprises densely cellular tissue with an
increased nuclear-to-cytoplasmic ratio and decreased intercellular
space, this restricts water motion, and hence, shows restricted
diffusion.
‐ However, post-treatment changes are less cellular and with
increased interstitial space. This forms the basis of differentiation of
ORN from tumour recurrence on DWI
17

18. PET
‐ Functional imaging technique, has been advocated to detect
tumour recurrence and differentiate it from ORN.
‐ FDG is known to accumulate in areas of inflammation, due to
uptake by the inflammatory cells. Dual-phase semi-quantitative
PET studies have been suggested, as the washout of FDG-6-
phosphate is delayed from malignant lesions as compared
with benign lesions. This may thus improve the specificity of
FDG-PET in differentiating recurrence from ORN.
18

19. 19
Treatment
Conservative
treatment
Surgical
treatment
HBO
Therapy

20. Conservative Treatment
 Initial treatment is directed at controlling infection.
 Hospitalization is recommended for patients who have
symptoms of toxicity and dehydration to allow supervised
administration of parenteral antibiotics and fluid.
 Penicillin plus metronidazole or clindamycin is
recommended.
 If abscess or fistula is present, aerobic and non-aerobic
cultures should be obtained for sensitivity testing.
 Supportive treatment with fluids and a liquid or semiliquid
diet, high in protein and vitamins.20

21. ‐ Irrigation of exposed bone should be performed ( high pressures
should be avoided)
‐ Exposed bone then should be mechanically debrided and
smoothed with large round burs and covered with a pack
saturated with zinc peroxide and neomycin.
‐ Irrigation and packing are repeated weekly until sequestration
occurs or the bone is penetrated by granulation tissue.
21

22. Surgical treatment - resection
22

23. 23

24. Prophylactic
measures
Before radiotherapy
24
Mouth should
be made as
clean as
possible
Infection of soft
tissues should
be eliminated
Infected and
nonvital teeth
should be
extracted
Teeth in the line
of irradiation
also should be
extracted
Antibiotics
before and after
extractions
No radiotherapy
after 7-10 days
of extraction
Fluoride therapy
Maintenance of
absolute
hygienic

25. After radiotherapy of the jaw
‐ Patients should be advised of the necessity for strict
oral hygiene and should be supervised
‐ Patients should be instructed that they must inform
the physician or dentist that their jaws have been
previously irradiated.
‐ No further extractions should be attempted in a
heavily irradiated jaw. If a tooth in the area of
irradiation has been left in situ and becomes involved
by caries, the extraction must be done as
atraumatically as possible and with the patient under
a course of antibiotics both preoperatively and
postoperatively.
25

26. Hyperbaric oxygen treatment
‐ Consists of breathing 100% oxygen
through a face mask in a monoplace
or a large chamber at 2.4 absolute
atmospheres pressure for 90 minute
sessions or dives for as many as 5
days a week totaling 30 or more
sessions often followed by 10 or
more sessions.
‐ HBO causes an increase in arterial
and venous oxygen tension, the
additional oxygen is carried in
26

27. ‐ Oxygen under increased tension enhances healing by a direct
bacteriostatic effect on microorganisms that renders them
susceptible to lower antibiotic concentrations and by
enhancing phagocytic killing.
‐ Also neoangiogenesis, fibroblastic proliferation and collagen
synthesis occurs.
‐ Proliferation of granulation tissue increases and advances
under increased oxygen tension from the nondiseased
periphery into necrotic bone.
‐ HBO treatment may account for marked decreases in pain
and trismus, closure of fistulas and complete clinical and
radiographic healing.
27

28. Marx University of Miami Protocol
28

29. Indication
s for
HBOT
29

30. Complications of HBO therapy
‐ Oxygen toxicity
‐ Seizures
‐ High pressure nervous syndrome
‐ Decompression sickness
‐ Pneumothorax
‐ Tooth and sinus pain
‐ Visual changes
‐ Gastric distress
30

31. Contraindications
Absolute contraindications
‐ Optic neuritis
‐ Immunosuppressive disorders
Relative contraindications
‐ COPD
‐ Claustrophobia
31

32. 32

33. 34

34. Possibilities of a surgical solution to prevent
osteoradionecrosis
‐ Important task during surgery is to maintain as far as possible the
integrity of the bone, and to leave the periosteum intact.
‐ An effort must be made not to bare the mandible then after the
intervention it should be covered in several layers with tissues with
a good blood supply.
‐ Operations interrupting the continuity of the mandible involve the
necessity of immediate reconstruction.
‐ Following irradiation, surgery must in all cases be performed only
under protection with broad-spectrum antibiotics.
35

35. Possibilities for the oncoradiologist to prevent
osteoradionecrosis
‐ The probability of osteoradionecrosis can be minimized if
special attention is paid in the course of the planning and
performance of the irradiation to exclusion of the mandible from
the target volume as far as possible, and to ensuring that the
bone is subjected to the lowest possible dose.
‐ This can currently be achieved with the greatest reliability
following the most modern, CT-guided, 3D irradiation planning,
with conformal irradiation via a Multi-Leaf-Collimator.
36

36. ‐ The dose that can be tolerated by the bone tissue depends on
the nature of the radiation applied, on its fractionation, and on the
dose per fraction
‐ The radiation therapy should be provided, if possible, with an
ultrapotential radiation source (telecobalt source and linear
accelerator) since the amount of radiation absorbed by the bone
tissue is then less than for radiation of lower energy.
37

37. ‐ Because of the steep fall in dose, irradiation with interstitial
brachytherapy is similarly suitable for the avoidance of
osteoradionecrosis. Via this method, by appropriate location of
the implants and by means of the X-ray pictures of this the
computerized planning system allows selection of the reference
points so that the radiation affecting the bone should be
minimized, or even eliminated
38

38. ‐ Newer RT techniques, such as intensity-modulated radiation
therapy (IMRT), have been introduced, which reduce the overall
incidence of ORN. IMRT is a high-precision technique, which
uses computer-controlled linear accelerators to deliver precise
radiation doses to a malignant tumour or specific areas within the
tumour. It thus allows higher radiation doses to be focused on the
tumour, while minimizing the dose to the adjacent normal
structures.
39
Peterson et al.11 reviewed 18-years of
literature regarding the impact of cancer
therapies on the
prevalence of ORN, and reported a weighted
ORN prevalence
of 7.4% for conventional RT, 6.8% for
chemoradiotherapy,
5.3% for brachytherapy, and 5.1% for IMRT
Deshpande SS, et al., Osteoradionecrosis of
the mandible: through a radiologist’s eyes,
Clinical Radiology (2014)

39. 40
FACTORS THAT MAY BE ASSOCIATED WITH THE RISK OF ORN
TREATMENT-RELATED
DOSE
IRRADIATED
MANDIBULAR
VOLUME
FIELD SIZE
BRACHYTHERAPY
+ EXTERNAL
BEAM
IRRADIATION
PATIENT-RELATED
ORAL HYGIENE
ALCOHOL +
TOBACCO ABUSE
EXTRACTIONS
TUMOUR-RELATED
SIZE
PROXIMITY TO
BONE
ANATOMIC SITE

40. DOSE
41
Fujita et al. observed a significant increase in
the incidence of bone complications when 60
Gy of brachytherapy at a dose rate of 0.55 Gy/h
or higher was combined with conventionally
fractionated external beam irradiation at a dose
above 30 Gy. Certainly, when combined
treatment is applied the dose threshold depends
on the brachytherapy dose rate.
All 20 events of ORN observed by
Glanzmann and Gratz among 189 patients
treated for oral cavity or pharyngeal cancer
were seen in patients treated with a total
target dose higher than 66 Gy.

41. Irradiated mandibular volume, radiotherapy field
size
and other technical aspects of treatment
‐ The analyses of the volume irradiated includes field
size (calculation of the part of the mandible within the
100% isodose) and the volume of the mandible
receiving the dose prescribed to the target.
42
Glanzmann et al. scored the irradiated mandible volume from 1
(radiotherapy field including only ramus ascendens) to 7 (whole
ramus horizontalis,chin region and angle included in the
radiotherapy field). On the basis of this score showed that inclusion
of more than a half of the horizontal ramus significantly increases
the risk of necrosis

42. Tumour-related factors
‐ A higher incidence of ORN was observed in tumours of
tonsillar or retromolar region as compared to other tumour
locations.
‐ Tumour size has also been found to be correlated with the
risk of ORN. However, this can partly be explained by the
higher radiation dose administered in higher stage
tumours.
‐ A higher risk of ORN has also been seen when the tumour
is in close proximity to bone.
43

43. Prevention
44
The optimization of the dose
distribution within the
irradiated volume through
the use of tissue
compensators and wedge
filters may allow both a
decrease in the maximum
dose absorbed by the
mandible and a reduction in
the proportion of the
mandible encompassed by
the high dose volume.
A further decrease in the
mandible dose may be
achieved by the use of
innovative techniques such
as intensity modulated
radiation therapy (IMRT).
In patients managed with interstitial
brachytherapy, particular attention
has to be paid to the distance
between the radioactive source and
the mandible. Direct infiltration of the
mandible or adjacent tumour are well
known contraindications for
brachytherapy due to the potential for
high dose exposure to the bone. This
limitation can be overcome with the
use of intraoral protective spacers

44. Reconstruction in ORN
‐ Free tissue transfer has become the established surgical
treatment of advanced ORN.
‐ Factors complicating outcomes in free flap reconstruction of
ORN defects include soft tissue radiation injury, infection,
extensive bony involvement, depleted recipient vessels
from previous neck dissection, and free flap reconstruction.
Therefore, postoperative complication rates in ORN
reconstructions are expected to be higher than in primary head
and neck resections/reconstructions.46

45. ‐ The reported complication rates for free flap reconstruction of
ORN defects range from 24% to 44%.
‐ Sandel and Davison report the fistula, hematoma, and flap
loss in ORN reconstructions are higher than ablative head and
neck free flap reconstructions.
‐ Reconstruction of ORN defects is usually more difficult due to
radiation damage, severe fibrosis, and a complex wound
environment
‐ Recipient vessel choices can be limited and dissection of carotid
artery branches can be difficult and risky.
47

46. 48
The goals
of surgical
intervention
for ORN
are
To relieve intractable pain
Control infection with thorough debridement
of infected necrotic bone and soft tissue
Provide bone continuity if possible
Improve overall function and quality of life
Repair soft tissue defects

47. 49

48. 50

49. ‐ Longer time intervals between radiation and ORN development led to
higher flap failure and overall complication rates.
‐ Studies suggest that these patients’ bodies have been most affected
by radiation therapy at the vascular level and had the most time to
develop soft tissue fibrosis. Both of these conditions would make the
patient more susceptible to flap failure and general wound
complication risks.
‐ The effect of chronic radiation on medium to large vessels is caused
by injury to the vasa vasorum owing to a greater incidence of
atherosclerosis within these vessels, a major concern in the use of
microvascular free flaps. 51

50. Vessel depleted neck and the choice of neck
vessels
‐ Treatment for cancer with surgery and/or RT results in
a vessel depleted neck adding to the challenges of
reconstruction of the ORN defect.
52
D’Souza J, Batstone M and Rogers S. Surgical Challenges in the Management
of Advanced Osteoradionecrosis of the Mandible. Austin J Otolaryngol.
2015;2(4): 1037.

51. 53
FACIAL ARTERY, FACIOLINGUAL TRUNK,
SUPERIOR THYROID ARTERIES
Damaged
Ligated
Lack pedicle
length
Utilized in the
previous free flap
Discrepancy in
caliber
TRANSVERSE CERVICAL OR INTERNAL
MAMMARY OR THE CONTRALATERAL
NECK VESSELS
ARTERIES

52. 54
VEINS
INTERNAL JUGULAR VEIN
EXTERNAL JUGULAR VEIN
In preparation for anastomoses, the authors recommend
minimal dissection of the IJV, as it tends to be friable and
prone for perforations and tears.
The availability of the IJV however cannot be guaranteed in the
previously operated neck, as noted in a study by Hanaso et al.
[25] reporting on the need to seek vessels other than IJV and
EJV in 16% cases.
A composite RFFF or a fibula FF affording good pedicle length
may be the only option in such cases.
Other techniques such as use of the cephalic vein located in the
deltopectoral groove and thoracoacromial/cephalic system have
been described.

53. Soft tissues defect and management of the
fistula
55
The extra-oral skin overlying an area of ORN is particularly susceptible to breakdown. Depending on
the quality of the external skin, consideration needs to be given to in inside and outside paddle.
Achieving primary closure at the skin incision site is
difficult. This may indicate the need for regular
dressings, skin grafts or provision of pedicled flaps or
free flaps with a soft tissue component.
A transverse incision in the supraclavicular fossa is
made to expose the transverse cervical vessels and
lower end of IJV for anastomoses. The pedicle is
tunneled through to the supraclavicular fossa to
facilitate anastomoses. It should be emphasized that
with this technique, the use of a free flap with a long
pedicle is mandatory.
As the oral fistula is frequently small,
and neck skin closure is problematic,
an alternative used frequently by the
authors is to obturate the oral fistula
with muscle) and the use of skin
paddle from the FF in the neck.

54. CONCLUSION
‐ ORN can lead to intolerable pain, fracture,
sequestration of devitalized bone and fistulas, which
makes oral feeding impossible. ORN is an expensive
disease to manage no matter what course of
treatment is used. Effective management of any
disease process initially requires diagnosis before
treatment. Criteria used to identify ORN vary even
among identical authors at different points in time. So,
it is important to make a correct diagnosis before
initiating a treatment. 56

55. THANK YOU
57