3. Case: Habtamu Aklilu 30yr/M
O Hx:
O Presented with RTA of 1 week durtion.
O Has no vomiting, seizure, loc but Has
headache since trauma that continued
worsening.
O No ear and nasal discharge.
O Referred from DBH.
O No previous surgery & known medical
illness.
3/26/2021 3
4. Pertinent P/E
O v/s: normal
O HEENT: has bilateral raccon eye &
subconjunctival hrge. No open wound.
O Neuro exam:
O GCS:15/15
O Pupil: mid sied & reactive to light
bilaterally.
O CN: all intact.
O Meningeal signs: +ve
O Lab Ix: normal 3/26/2021 4
6. Introduction
O Frontal sinus fractures account for 5–15%
of facial fractures.
O The thick cortical bone of the anterior
table of the frontal sinus is more resistant
to fracture than any other facial bone [2].
O 2*mandible and 5* maxilla:
pneumatization & thick anterior wall.
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7. Basics of Frontal Sinus
O The only paranasal sinus not present at birth
O Bilateral agenesis : 4%
O Pneumatization : begins after the 2nd yr.
O Radiologicaly evident at 8 yrs
O Adult size attained at 15 yrs.
O Anterior and posterior wall: 4-12 & 0.1-4.8
mm.
O Ciliated pseudostratified columnar
O Opens into the middle nasal meatus
3/26/2021 7
8. FS fractures pattern: four
Categories
O Isolated anterior table fractures:50%
O Isolated posterior table fractures
uncommon,
O Combined anterior and posterior
table fractures:most common
O Fractures with involvement of the NFD
or NFOT.
3/26/2021 8
9. Ix
O High-resolution 0.5 mm CT:gold standard
i. Axial : presence and degree of
displacement of anterior and posterior table
fractures;
ii. Coronal : floor of the sinus and orbital roof;
iii. Sagittal : NFOT injuries
O Endoscopic evaluation
O Methylene blue/fluorescine dye
O CT cisternography: fistula accurate
localization
3/26/2021 9
10. Why is FS # important?
i. Chronic frontal headache due to injury to the
supraorbital nerve
ii. Chronic CSF leak
iii. Chronic frontal sinusitis
iv. Mucocele
v. Mucopyocele
vi. Subdural empyema
vii. Frontal bone osteomyelitis
viii. Meningitis
ix. Brain abscess (due to spread of infection from the
FS
intracranially via foramina of Breschet)
x. Residual forehead contour defects and deformities.
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11. Mgt
Factors
O Location of the fracture, (Involvement of anterior,
posterior or both walls of the sinus.)
O Presence and degree of displacement of the
fractured fragments,
O Status of the NFOT,
O Degree of injury to the dura mater and brain (CSF
leak),
O The presence of other associated
craniomaxillofacial injuries, and
O Associated neurological injuries
3/26/2021 11
12. Treatment options
O Observation,
O Reconstruction of the sinus walls /ORIF/
O obliteration
O osteoneogenesis
O cranialization.
O ablation/exenteration
3/26/2021 12
13. Conservative treatment
O Bed rest
O Oral acetazolamide 250 mg every 8
hours,
O Laxatives and
O Prophylactic
antibiotics/vaccination???
O Avoidance of breath holding and straining.
O LP
3/26/2021 13
14. Principles in mgt of FS #
O Restoration of normal sinus mucosa with a patent
drainage system
O Eradication of the sinus cavity if the normal
mucosa or drainage system cannot be
reestablished,
O Creation of a permanent barrier between the
intracranial and extracranial systems to px
infection
O Protection of the intracranial contents
O Protection of the orbital contents
O Control CSF leakage/rhinorrhea,
O Prevention of posttraumatic wound infection
O Restoration of an esthetic 3/26/2021 14
19. Approach
O Bicoronal: work horse of frontal sinus
surgery
O suprabrow approach
O upper eyelid approach
O Subbrow
O Transnasal
3/26/2021 19
20. Choice of graft for Obliteration
of the frontal sinus
O Autogenous fat
O Autogenous muscle
O Autogenous bone
O Pericranial flap
O Allografts like lyophilized cartilage
O Alloplastic materials: E.g Hydroxyapatite
O Spontaneous obliteration
3/26/2021 20
25. References
O Greenburg 9th edition
O Youman 7th edition
O ENT journals
O Craniofacial journals
O Neurosurgery journal
3/26/2021 25
Editor's Notes
y 1/3 is isolated to the anterior table and 2/3 are a combination of anterior table, frontal recess, and posterior table [1]. Isolated posterior table fractures are rare
The posterior wall provides attachment for SSS (vulnerable in fractures of the posterior wall but is rare).
rupture is uncommon because the dura is tough and unyielding, and the sinus is often atretic for some distance from its origin, close to the frontal sinus.
Prophylactic antibiotics/vaccination
Controversial even in the presence of a CSF fistula
However, most ENT physicians recommend treating fractures through the nasal sinuses as open contaminated fractures, and they use broad spectrum antibiotics (e.g. ciprofloxacin) for 7–10 days.
If there is a CSF leak pneumococcal vaccine is recommended for adults age 2–65 years
difficult to diagnose even on CT scans.
sagittal reconstruction of the paranasal sinuses besides axial and coronal CT image.
Naso-orbitoethmoid (NOE) complex fractures, anterior skull base injuries near the junction of the posterior table and cribriform plate of ethmoid, fractures involving the floor of the FS, depressed or inferiorly located fractures of the posterior table of the FS, etc., are strongly suggestive of the possibility of NFOT injuries
The presence of sinus opacity or air‑fluid level within the FS persisting for more than 7–10 days following the trauma/injury.
A unilateral air‑fluid level indicates patency of the contralateral NFD.
Removal of the intersinus septum (intersinus septectomy), using the osteoplastic flap approach, the so-called “Lothrop procedure,” or
When disruption of both the nfds is evident upon exploration or suspected due to persistent bilateral air‑fluid levels, complete fs obliteration is the treatment of choice.
Endoscopic frontal sinusotomy /dilatation of NFD with stent/ for NFOT recanalization too is prone to failure.
FS exclusion either by its obliteration or cranialization.
CSF leak with minimally displaced posterior table fracture, an initial conservative approach by observation for 5–7 days with administration of intravenous antibiotics, bed rest, head elevation, and if indicated, lumbar drainage at 10cc/h may be employed.
if there is a persistent CSF leak beyond 8–10 days, FS obliteration via either osteoplastic flap approach or bifrontal craniotomy is indicated.
When disruption of the posterior table is more than 25%, and there is associated dural tear and CSF leak, cranialization of the sinus with dural repair is indicated. Cranialization
is the most radical method of FS management.
It is obliteration with complete removal of the posterior table.
A number of autogenous and alloplastic materials have been used as fillers in FS obliteration. Autogenous fat is probably the most widely used and has the longest tradition [47]. The advantages of fat grafts include ease of harvest, minimal donor site morbidity, ample available volume, and favorable handling characteristics. However, complication rate was reported as high as 18% [48]. Magnetic resonance study 24 months post-operatively found vital fatty tissue in only 6 out of 11 cases of obliteration of FS via an osteoplastic approach. Fatty necrosis occurred five times; whereas in four cases a transformation into granulation tissue and in one case into connective tissue could be seen [49].The harvest of the fat is performed using sterile technique: the surgeon will rescrub and a separate set of instruments that have not come in contact with the infected field is used. A transverse incision is made in the left lower abdominal quadrant, and subcutaneous fat is removed. Alternatively, a periumbilical incision can also be made. Bleeding is controlled using monopolar cautery, but excessive cauterization should be avoided because it may harm the fat cells and result in graft failure. Drainage of the abdomen is usually not necessary. [46] Autogenous muscle graft harvested from temporalis muscle has advantage of being located within the operative field and being available in adequate volume. Like autogenous fat graft, this nonvascularized graft undergoes necrosis and eventual replacement by fibrous tissue. Donor site morbidity, including temporal hollowing and trismus, is unacceptable. [37] Autogenous bone graft for FS obliteration was first described in 1969 [50]. Since then, cancellous bone grafts, most often harvested from the ilium, have been widely used as a filler material. Cancellous bone promotes re-ossification from both the periphery of the defect and centrally. The main contributions of the grafts are their osteoconductive properties and osteoinductive factors that are released from them during the process of resorption. [51] Another advantage of cancellous bone over adipose or muscle tissue for obliteration is that it Contemporary Management of Frontal Sinus Injuries and Frontal Bone Fractures http://dx.doi.org/10.5772/59096 451 is easier to distinguish radiographically in postoperative period between resorption, infection, and mucocele formation.[13,37] The greatest disadvantage to the use of cancellous bone grafts lies with the potential donor site morbidity. [52] Much more comfortable and safer is to harvest bone chips from adjacent calvarium. It can be done using bone scraper. In case the harvested amount of bone is not sufficient for filling of a large sinus, it can be augmented by admixture of bone substitute such as demineralized bone matrix (Figure 10) [53].
Pericranial flap has been widely used in anterior cranial fossa repair, reconstruction of the middle third of face defects, full-thickness scalp defects, and orbital defects. It is composed of the skull periosteum and the subgaleal fascia. The anteriorly based flap receives its blood supply from the supraorbital and supratrochlear arteries. Branches of the superficial temporal 452 A Textbook of Advanced Oral and Maxillofacial Surgery Volume 2 artery supply the laterally based flap. In contrast to all other avascular grafts used for sinus obliteration, the anteriorly based pericranial flap is composed of a well-vascularized tissue. The high vascularity makes this flap less prone to infections and turns it into an ideal method for obliteration of an infected cavity in a contaminated surgical field. [54] Allografts like lyophilized cartilage [55] have the advantage of unlimited availability and lack of donor site morbidity. They are easy to handle, well adaptable to the defect, and thus reduce the operative time. Nevertheless, a failure in revascularization or subsequent osseointegration may occur, with associated risk of infection and extrusion [56]. Allogenic transplantation may be associated with increased risk of transmitting such diseases as hepatitis, AIDS or bovine spongiform encephalopathy. Alloplastic materials.Methyl methacrylate has been widely used alloplastic material since its introduction in 1940. It is well tolerated by soft tissues and has a density similar to bone, low thermal conductivity, and acceptable strength. However, the material produces a significant exothermic reaction during polymerization and foreign body reaction has been noted when it is polymerized in contact with tissue. [57] Hydroxyapatite is a nonceramic calcium phosphate substance (BoneSource, Stryker Leibinger). It has osteoconductive properties, may be contoured to a defect, adheres to adjacent bone, has the ability to resist mucosal ingrowth, is resistant to infection, and is gradually replaced by native bone without a loss of volume. It has been investigated in experimental and clinical frontal sinus obliteration, but no long term observation results were reported [58]. Currently the use of hydroxyapatite cement in FS is not recommended. Significant problems related to material failure have been reported. [37] Glass-ionomer cement is a hybrid glass polymer composite consisting of inorganic glass particles in an insoluble hydrogel matrix and bonded by ionic cross-links, hydrogen bridges, and chain entanglements. It is widely used in dentistry and also has been used in frontal sinus reconstruction [59]. However, because of severe complications after using glass ionomer cement next to dura mater this material has been taken off the market. [51] Proplast, a polytetrafluoroethylene (Teflon) polymer with vitreous carbon fibers with pore sizes of 200 to 500 μm, is extremely porous to body fluids. Fibrous tissue ingrowth occurs rapidly and acts to mechanically stabilize the material. The material can cause a mild foreign body reaction. [51, 60] Glass ceramic(bioactive glass) has proved biocompatible, non-toxic and bone conducting material for occlusion of bone cavities. Total accurate obliteration of the sinus is achieved with different sizes of granules and blocks. Uneventful recovery and clinical outcome were seen in 92% of patients. Histopathological samples revealed a healing process progressing from the fibrous tissue phase to bone formation with scattered fibrous tissue and granule remnants. Bone produced by replacement of material was similar to natural frontal bone. Microbiologic cultures obtained with histological samples revealed no growth of bacteria. [61, 62] Spontaneous obliteration was reported long ago by Samoilenko (1913), who found oblitera‐ tion by osteofibrous ingrowth in an experimental study on cats and dogs. His results were Contemporary Management of Frontal Sinus Injuries and Frontal Bone Fractures http://dx.doi.org/10.5772/59096 453 confirmed by later experimental studies that found subsequent replacement of obliterated FSs by cancellous bone to a variable degree. [51] Because FS after removal of all of its mucosa and occluding the nasofrontal duct is nothing more than an isolated bone cavity, it is not irrational to expect its gradual ossification. [63]
