PARANASAL, PARANASAL, SINUS, PNS, RADIOLOGY, CT, SCAN, TUMOUR,CANCER,NOSE, INFECTION, TRAUMA, HEADACH,MRI,XRAY,X-RAY,DISORDER,DISEASE

1. PNS
A.
B.
C.
D.
NEOPLASM & METASTATIC
TRAUMA
INFECTION
CONGENITAL

2. (A) NEOPLASM
( 1 ) EPITHELIAL TUMORS
i. Papiloma
ii. Squamus Cell Carcinoma
iii. Sinonasal Undifferenciated
Carcinoma
iv. Adenocarcinoma
v. Adenoid Cyst Carcinoma

3. ( 2 ) NON EPITHELIAL TUMORS
i) Neuro Ecto-Dermal Tumour
ii ) Vascular
iii) Soft Tissue Tumors
iv) Osseous and Cartilaginous Tumors
v) Hematologic Tumors
vi) Fibro-Osseous Disease
vii) Metastasis

4. PAPILLOMA
Definition
Benign tumor of nasal cavity composed of vascular connective
tissue covered by well-differentiated stratified squamous
epithelium that tends to grow under and elevate mucosa
(inverted).
Clinical Features
▬ Less common than allergic polyps; less than 3% in general
population.
▬ Most common in males aged 40–70 years.
▬ Unilateral from lateral sinus wall near ethmoids.
▬ Nasal stuffiness or obstruction.
▬ Secondary bacterial sinusitis.
▬ Postoperative recurrence 35–40%.
▬ May be associated with malignancy (about 10%).

5. Imaging Features
▬ Small to extensive mass
▬ Bone remodeling that may deviate, not cross nasal septum
▬ Mass may extend into ethmoid or maxillary sinuses
▬ T1-weighted MRI: low or intermediate
▬ T2-weighted MRI: infermediate to high, usually high
▬ T1-weighted post-Gd MRI: some contrast enhancement

7. (A/1/i ) Papiloma (Inverted)

8. ( A/1/ii ) Squamus Cell Carcinoma
 50–80% of all malignant sinus masses.
 More than 60% originate in maxillary sinuses, followed
by nasal cavity, and ethmoid sinuses.
 Oral symptoms and signs may be initial; occasionally
considered an intraoral cancer clinically.
 SCC rarely arises from the ethmoid, frontal or sphenoid
sinus.
 Peak incidence is in the sixth and seventh decades,with
a male predominance (2:1).
 Occupational factors (including nickel, chromium,
thorotrast and radium exposure) are associated with an
increased risk.

9. Imaging Features
 Usually advanced when detected; bone destruction in 80%.
 Alveolar bone destruction reported in half of patients with
maxillary sinus carcinoma.
▬ Soft-tissue mass
▬ Bone radiolucency, secondary invasion of bone
▬ Border of bone destruction ill-defined
▬ Bone invasion frequent in gingival mandibular cancers,
generally considered to be about 50%,but up to 85% reported
in upper jaw; maxillary sinus frequently involved
▬ Floating teeth; tooth resorption uncommon
▬ Advanced stage: pathologic fracture
▬ T1-weighted MRI: intermediate–low signal
▬ T2-weighted and STIR MRI: high signal
▬ T1-weighted MRI: contrast enhancement

11. SCC does not show specific MSCT or MRI characteristics. The main goal
of imaging is to determine the submucosal extent of sinonasal
neoplasms.

12. ( A/1/iii )Sinonasal Undifferentiated Carcinoma
and Neuroendocrine Carcinoma
 SNUC is a malignant tumor with slight male predominance
 peak of incidence in the fifth and sixth decades.
 Short-time history of symptoms (mainly consisting of nasal
obstruction with epistaxys), largesize at presentation .
 high incidence of nodal metastases (15–20% of cases)
denote the aggressive nature of this neoplasm

14. ( A/1/iv ) Adenocarcinoma
Adenocarcinoma is a malignant neoplasm.
more frequently observed in the ethmoid
sinus.
predilection for men in the fifth to seventh
decade.
composed of epithelial cells, arranged in a
glandular or gland-like pattern.
Occupational ITAC is strongly related to
softwood dust and leather dust inhalation

15.  Imaging appearance
 ITAC may show a mixed solid–fluid pattern due to mucus
produced by tumoral cells .
 Mild discrimination occur between the lesion and
retained secretions (or mucocele) due to sinus blockage;
 meticulous attention should therefore be paid to the
presence of any solid component within a mucocele,
 combining the information provided by pre- and
postcontrast sequences and by diffusion-weighted
sequences (when not degraded by artifacts).

17. A/1/V - Adenoid Cystic Carcinoma
 There are 450–750 minor salivary glands scattered in the whole head and neck
area, including sinonasal cavities. Adenoid cystic carcinoma (ACC) is a variant of
adenocarcinoma arising from minor salivary glands.
IMAGING FINDINGS
 peculiar tendency of this tumor to grow submucosally and subperiosteally, thus
permeating bone and soft tissues.
 Invasion of muscles, vessels and fat tissue may be detected on imaging studies as
effacement and encasement with no or very limited mass effect.
 Similarly, replacement of spongiotic bone may occur with minimal changes of the
cortical bone; furthermore, tumor growth on both surfaces of a cortical bone (such
as the posterolateral maxillary sinus wall) may be seen with only focal bone
destruction.
 findings are much better demonstrated on MRI, because of its high contrast
resolution: plain SE T1 and 3D GE T1 with fat suppression are key sequences.

19. ( 2 ) NON EPITHELIAL TUMORS
i) Neuro Ecto-Dermal Tumour
ii ) Vascular
iii) Soft Tissue Tumors
iv) Osseous and Cartilaginous Tumors
v) Hematologic Tumors
vi) Fibro-Osseous Disease
vii) Metastasis

20. A/2/i - Neuro-Ectodermal Tumors
• Olfactory Neuroblastoma
• Ewing Sarcoma and Peripheral Neuroectodermal
Tumor
• Melanoma

21. Olfactory Neuroblastoma
 Esthesioneuroblastoma , is a rare malignant tumor (2% of all
sinonasal tumors) arising from the olfactory epithelium.
 normally found in the cribriform plate, the ethmoid roof, the
upper part of the nasal septum and the superior turbinates.
 on cross-sectional imaging ONB is often seen as a dumbbellshaped mass growing across the cribriform plate.
 MSCTshows the mass exhibits spontaneous hyperdensity
(reflecting high cellularity) and calcifications of variable size.
 MRI pattern is composed of intermediate T2 signal and T1
hypointensity;
 cystic areas may be found, capping the intracranial part of the
tumor.
 Both iodine and paramagnetic contrast enhancement is strong
sometimes making the differential diagnosis with vascular
tumors is difficult.

22. a–c Olfactory neuroblastoma. A strongly enhancing mass with intermediate TSE T2 signal
intensity originates from the left ethmoid roof and encases the superior turbinate (st).
The mass is limited to the nasal cavity; the paranasal sinuses and the anterior cranial fossa are
not invaded (Kadish stage A). Retained secretions are seen into the posterior ethmoid cells
(asterisks)

23. Ewing Sarcoma and Peripheral
Neuroectodermal Tumor
Definition
Malignant tumor with rather uniform histologic
appearance composed of densely packed, glycogenrich small cells with round nuclei but without
prominent nucleoli or distinct cytoplasmic outlines.
Tumor tissue is typically divided into irregular strands
or lobules by fibrous septa,but intercellular network
of reticulin fibers, which is a feature of malignant
lymphoma, is not seen. Mitoses are generally
infrequent. Hemorrhage and extensive areas of
necrosis are common (WHO).

24. Clinical Features
▬ Only 1–4% in head and neck area; most commonly
mandible
▬ Hard swelling, pain or pain-free
▬ Males more frequent than females
▬ Usually first and second decades, but may occur at any age
Imaging Features
▬ Soft-tissue mass
▬ ‘Moth-eaten’ bone destruction
▬ Bone production characteristic; periosteal ‘onion mskin’
reaction (usually in long bones), but not so typical in jaw

28. Ewing sarcoma, mandible; 24-year-old female with 10-year
history of Ewing sarcoma treated with radiotherapy and
chemotherapy, and a rather unchanged condition; now with
pain and swelling and new soft-tissue mass,possibly due to
infection.A Panoramic view shows bone production in entire
half of mandible (arrow).B Axial CT image shows bone
production both buccally and lingually (arrow)

29. Melanoma
 arises from melanocytes that migrated during embryonal
life from the neural crest to the mucosa investing the nasal
cavity and sinuses.
 nasal septum and lateral nasal wall are the most common
sites of origin, and maxillary sinus is the most frequently
involve.

30. Imaging studies,
 Appears as a solid soft tissue mass with local invasion
and relatively high tendency to nodal spread.
 A T1 spontaneous hyper intensity, atypical for nearly all
other benign and malignant sinonasal tumors, is much
more requently exhibited by the melanotic variant;
(this is explained by the paramagnetic properties of
melanin as well as by intralesional hemorrhage. )
 Secondly, flow voids may be demonstrated on MRI
sequences at the periphery and into the lesion,
representing its rich vascular network; such finding
explains the frequent epistaxis occurring in patients
 affected by melanoma

32. A/2/ii -Vascular Tumors
•
•
•
•
Juvenile Angiofibroma
Lobular capillary hemangioma (LCH)
Angiomatous Polyp
Hemangiopericytoma (HPC)

33. Juvenile Angiofibroma
Juvenile angiofibroma (JAF) is a highly vascular
mass characterized by three distinctive
features:
exclusively in male adolescents;
originathe posterior nasal fossa,
close to the sphenopalatine foramen;
it is composed of irregular vessels set in a
fibrous stroma . The typical clinical symptoms
are nasal obstruction and epistaxistes.

34. Imaging Finding
 JAF appears as a solid, brightly enhancing lesion vegetating in the
posterior nasal cavity and nasopharynx and invading the
pterygopalatine and infratemporal fossa;
 A combination of TSE T2 and SE T1 (before and aftercontrast
administration) is essential, for characterization of JAF, and the
assessment of spongiotic bone invasion;
 when JAF approaches the cavernous sinus, submillimetric 3d GE T1
sequences allow to define the relationships between the lesion
and vascular or nervous structures.
 The role of MSCT is restricted by the issue of radiation exposure and
by the lack of contrast resolution in grading medullary bone
involvement; In selected cases, a volumetric data set acquired with
MSCT is the basis for intraoperative navigation systems, which allow
safer control of critical structures such as the internal carotid artery
and the optic nerve.

35. 14 year male, affected by juvenile angiofibroma. A large, intensely
enhancing mass (b, c) occupies the left nasal fossa laterally displacing
the nasal septum (arrowheads in a), nasopharynx and sphenoid sinuses.
TSE T2 (a) shows several vascular flow voids into the lesion. Through an
enlarged sphenopalatine foramen (arrows) the mass protrudes into the
PPF. The lesion encroaches the ethmoid planum and sphenoid sinus
roof, displacing the dura, appearing thickened and enhancing (arrows in
b, c)

36. Lobular Capillary Hemangioma
 Also referred to as pyogenic granuloma, is a benign vascular tumor
composed of capillaries arranged in lobules into an edematous and
fibroblastic stroma.
 Arises from the anterior nasal septum, although skin and oral
mucosa are the preferred head and neck sites of origin.
 On MSCT, LCH appears as a soft tissue density mass that may cause
bone remodeling and destruction;
 MRI pattern consists of T2 hyperintensity and spontaneous T1
hypointensity. Bright enhancement is obtained after contrast agent
JAF is the only differential diagnosis that can be readily ruled out,
based on the typical site of origin, pattern of growth, age and sex
of the patient.

37. 23 year male. A large mass with hyper TSE T2 signal (a) and bright contrast enhancement (b, c)
fills the ethmoid cells and protrudes into the frontal sinus (arrowhead).
The sharp interface between the lesion and both the orbital and intracranial content (arrows)
indicates low aggressiveness.
Pathologic examination of the surgical specimen revealed lobular capillary hemangioma

38. Angiomatous Polyp
 It is a sinochoanal polyp whose vascular pedicle is strangled
by the pressure exerted by the bony walls of the foramen
through which it exits sinus cavity of origin to reach the nasal
cavity.
 Such compression may trigger a cascade of dilatation and
stasis of feeder vessels, necrosis (which in some cases
prevails) and neovascularization.
 The site and pattern of growth of the lesion as well as its
mixed appearance (fluid-like intensity/density of the sinusal
component, intense enhancement of its vascular
compromised portion) are sufficient clues for the diagnosis on
imaging studies.

39. a, b 26 year female. Post contrast SE T1 shows an antrochoanal polyp. The vascular
compromised part of the lesion, strangled as it courses through an accessory ostium (arrows), is
referred to as angiomatous polyp.

40. Hemangiopericytoma
 Hemangiopericytoma (HPC) is a vascular tumor
 that can either be benign or malignant and may be found in any part of the
body; 15–20% of cases arise from the head and neck, 5% in the sinonasal
region. HPC originates from pericytes, mesenchymal cells covering the
outer surface of capillaries, implied in flow regulation and vasoconstriction.
 Interestingly, four cases ofoncogenic osteomalacia (a rare condition
manifesting with muscle weakness, bone pain and frailty)
 On both MSCT and MRI, HPC appears as an indistinct soft tissue mass with
moderate to bright contrast enhancement; bone changes (remodeling,
destruction) are generally also found. Lesions arising in the sinonasal tract do
not show aggressive behavior, distant metastases are rare.

42. A/2/iii – soft tissue tomors
•
•
•
•
Peripheral Nerve Sheath Tumor
Nasal Glioma
Meningioma
Rhabdomyosarcoma

43. Peripheral Nerve Sheath Tumor
 generally benign in nature.
 Schwannoma more commonly affects the ethmoid
followed by the nasal septum and maxillary sinus,
usually as a solitary lesion.
 Neurofibroma is classically described as localized,
diffuse and plexiform.( Rarely malignant transformation
spindle cell sarcoma).
 Triton tumor is a neoplasm composed of peripheral
nerve fibers and well-differentiated striated muscle
fibers, described as either benign or malignant

44. Schwannoma
Definition
Benign nerve sheath tumor emanating from Schwann cells. (The terminology is confusing. The
following terms have been used for the same tumor: schwannoma, neuroma, neurinoma,
neurolemmoma, perineural fibroblastoma.)
Clinical Features
▬ Asymptomatic mass.
▬ About 13% of schwannomas are found in head and neck, most in the lateral cervical region.
▬ Almost half of oral schwannomas reported to occur in the tongue.
Imaging Features
▬ Well-defined homogeneous soft-tissue mass, enhancement, but variable appearance
because of cystic and solid components. Schwannoma is often cystic, as opposed to neuroma,
which is seldom cystic.
▬ Enlarged foramina.
▬ Atrophy of muscles.
▬ Associated with neurofibromatosis.
▬ T1-weighted MRI: isointense with muscle.
▬ T2-weighted MRI: hyperintense, homogeneous, both cystic and solid components, or
heterogeneous.
▬ T1-weighted post-Gd MRI: cystic nature with rim enhancement.

46. Nasal Glioma
 Nasal glioma is a congenital fronto-nasal mass composed of
dysplastic neuroglial tissue and fibrovascular tissue.
 This mass is thought of as a cephalocele that lost connection to the
skull base. It is found at birth or during infancy as a subcutaneous
lesion located on the nasal dorsum, typically at the glabella,,on the
midline (although this is not the rule)
 MRI should be considered the imaging technique of choice, because
its low invasiveness and better depicts the absence of connections
with the brain;
 the lesion displays hypointense T1 signal (as compared to gray
matter) and T2 hyperintensity (due to gliosis); no contrast
enhancement is expected.

48. Meningioma
 Meningioma may be found in the sinonasal cavities in four different
forms: as the direct extension of a lesion arising in anterior cranial
fossa; as a metastasis of an intracranial meningioma; as an
extracranial neoplasm arising from arachnoid cells located in the
sheath
 surrounding cranial nerves in their course through skull base
foramina; as an extracranial lesion with no connection with the
anterior cranial fossa .
 The nasal cavity is the most common site of sinonasal meningiomas.
 MSCT density is generally homogeneous, MRI signal is iso- to
hyperintense on T2 sequences and iso- to hypointense on T1,
compared with gray matter; contrast enhancement is bright. Bone
erosion, sclerosis and hyperostosis may be found.

50. Rhabdomyosarcoma
 Rhabdomyosarcoma is the most common sinonasal malignant
tumor in children,
 characteristic are aggressive local behavior and early
metastases. Three subtypes (embryonal, alveolar and
pleomorphic) are described, however the differentiation may
be difficultat histology.
 As the nasal symptoms produced by this tumor are similar to
allergic or infectious diseases, at the time of diagnosis
rhabdomyosarcoma is often a large mass invading adjacent
structures.
 On MRI, TSE T2 signal is hyperintense to muscle.
 Contrast enhancement is heterogeneous; necrosis,
calcifications and hemorrhage are rare (Hagiwara et al. 2001).

52. A/2/iv - Osseous and Cartilaginous
Tumors
• Osteosarcoma
• Chondrosarcoma
• Ameloblastoma

53. Osteosarcoma
Synonym: Osteogenic sarcoma
Definition
Malignant tumor characterized by direct formation of bone or osteoid by tumor cells
(WHO).
Clinical Features
▬ Most common primary malignancy in skeleton (apart from myeloma), usually in
bones around the knee and primarily in children and adolescents; pain common
▬ Only 5–10% in head and neck; mostly in jaws
▬ Usually painless swelling in jaws,but also pain and mental nerve paresthesia
▬ Mandible slight predominance
▬ Males slight predominance
▬ May occur in any age group; peak in fourth decade
▬ Jaw osteosarcomas have tendency to occur in older patients than osteosarcomas in
other bones and less likely to metastasize
▬ However, prognosis of jaw sarcoma is poor and does not seem to have improved
with chemotherapy in a similar way to sarcomas in other bones

54. Imaging Features
▬ Soft-tissue mass, may grow aggressively and rapidly
▬ Radiolucent or most frequently, a combination of radiolucent
and radiopaque appearance; bone production may be extensive
▬ Border of bone destruction ill-defined
▬ Bone production may typically have ‘sunburst’ appearance, best
seen on CT images
▬ T1-weighted MRI: heterogeneous (intermediate–low) signal
▬ T2-weighted and STIR MRI: heterogeneous signal (variable high
to intermediate–low) epending on bone production and cellular
content
▬ T1-weighted post-Gd MRI: heterogeneous (intense to low)
contrast enhancement

57. Chondrosarcoma
 Chondrosarcoma generally affects long bones, ribs and pelvis;
 60% of cases occurring in the alveolar process of the maxilla, although several
cases of nasal septal chondrosarcoma are reported.
 Sinonasal chondrosarcoma tend to be high grade lesions,.
Imaging feature
 MSCT appearance consists of a soft tissue matrix with scattered calcifications
(which may represent a helpful hint for the differential diagnosis) and bone
destruction.
 On MRI, chondrosarcoma exhibits bright T2 signal and T1 hypointensity with
variable, heterogeneous contrats enlacement .
 Typically, scalloped margins and intralesional septa display enhancement, resulting
in a peculiar rings and arcs pattern.
 Although calcifications are less evident than on MSCT, the T2 hyperintensity
(uncommon for neoplasms) and pattern of enhancement may suggest
chondrosarcoma on MRI.

59. Ameloblastoma
 benign but locally aggressive neoplasm
 originate from remnants of the odontogenic epithelium,
from the lining of odontogenic cysts or from the basal
membrane of the overlying oral mucosa.
 The mandible and maxilla as common site of origin (80 vs.
15–20% of cases),
 fifth and sixth vs. second and third decade
 to show more aggressive behavior than those originating
from the jaw.

60.  Imaging feature
 On cross-sectional imaging, appear as a uni- or multilocular cystic and
solid lesion arising from the alveolar ridge.
 Bone remodeling and destruction are often seen, along with maxillary
sinus and nasal cavity invasion.
 A peripheral (generally incomplete) bony shell may surround the lesion
the presence of multiple septa within the lesion may result in a
honeycomb appearance;
 In 10% of cases a dental element may be embedded into the lesion .
 MRI appearance of plexiform ameloblastoma may be similar to the
columnar pattern of inverted papilloma: this is due to the presence of
thin septa and papillary projections of solid tissue within the lesion,
both enhancing after contrast administration

61. a–c 73 year male. The left maxillary sinus is occupied by a mass protruding in the nasal fossa.
Although the upper part of the mass (arrows) shows a columnar pattern resembling inverted
papilloma, the destruction of the posterolateral sinus wall (b) indicates a more aggressive
pattern of growth. Involvement of the alveolar process of maxillary bone (arrowheads)
suggests odontogenic origin. Pathology proved the lesion to be ameloblastoma

62. A/2/V - Hematologic Tumors
•
•
•
•
•
Lymphoma
Granulocytic Sarcoma
Plasmacytoma
Fibro-Osseous Disease
Metastasis

63. Non-Hodgkin’s Lymphoma
Definition
Malignant neoplasm of cells from the lymphatic system.
Clinical Features
▬ Lymph node disease most common
▬ Non-Hodgkin’s lymphoma of involves extranodal sites (as
opposed to Hodgkin’s lymphoma which is predominantly
nodal)
▬ Extranodal involvement may include maxillary sinus and
maxilla or, less frequently, mandible
▬ All age groups, adults in particular (except Burkitt’s
lymphoma)
▬ Burkitt’s lymphoma was initially described as African jaw
lymphoma; affects children; shows rapid growth and may
involve one or both jaws

64. Imaging Features
▬ Soft-tissue mass
▬ Radiolucency
▬ Border of bone destruction ill-defined
▬ Non-Hodgkin’s lymphoma, and rarely Hodkin’s lymphoma, may
present with necrofic lymph nodes
▬ However, it is not possible to definitely distinguish between nonHodgkin’s,Hodgkin’s and metastatic lymph nodes based on CT and
MRI
▬ T1-weighted MRI: intermediate–low signal
▬ T2-weighted and STIR MRI: intermediate signal
▬ T1-weighted MRI: contrast enhancement

68. Granulocytic Sarcoma
 Also known as chloroma, granulocytic sarcoma is a rare tumor
composed of precursors of the granulocyte series, including
myeloblasts, promyelocytes and myelocytes.
 develop during the course of, or as a presenting sign of a variety of
myeloproliferative disorders among which is acute myelogenous
leukemia; seldom, granulocytic sarcoma may even precede leukemia
by weeks or months.
 Although more commonly described in the orbit
 (actually it was first described as a green ocular tumor hence the
name chloroma),
 Imaging shows a homogeneously enhancing soft tissue mass.

70. Plasmacytoma
 Plasmacytoma is a soft tissue mass composed of monoclonal plasma
cells.
 most commonly affecting the sinonasal cavities, followed by the
nasopharynx and oropharynx, and manifesting in 90% of cases as a
solitary mass .
 15–20% of plasmacytomas convert into multiple myeloma, although
such transformation is thought to occur in intramedullary lesions,
whereas extramedullary lesions (such as sinonasal plasmacytoma)
are generally solitary lesions.
 Imaging findings (soft tissue mass, bone destruction) are completely
nonspecific

73. Fibrous Dysplasia
Definition
Genetically based sporadic disease of bone that may affect single or
multiple bones monostotic or polyostotic). Fibrous dysplasia occurring
in multiple adjacent craniofacial bones is regarded as monostotic
(craniofacial fibrous dysplasia).May be part of the McCune-Albright
syndrome (WHO). Non-neoplastic, self-limiting but non-capsulated
lesion occurring mainly in young subjects, showing replacement of
normal bone by cellular tissue containing islands or trabeculae of
metaplastic bone.
Clinical Features
▬ Monostotic most common (70–80%, femur, ribs)
▬ Craniofacial bones up to 25% of monostotic forms
▬ Maxilla, lateral region in particular,more frequent than mandible
▬ Painless swelling, jaw asymmetry
▬ Second and third decades
▬ No sex predilection
▬ McCune-Albright syndrome; polyostotic

74. Imaging Features
▬ Radiolucency
▬ Mixture of radiolucency and radiopacity
▬ Radiopacity; ground-glass appearance
▬ Unilocular or multilocular
▬ Border poorly defined; blend into normal bone, but may be more
well defined (and thus difficult to distinguish from ossifying fibroma;
same histopathology)
▬ Usually expanded bone
▬ May displace teeth, walls of nasal cavity, paranasal sinuses, orbits
▬ Mandibular canal may be displaced cranially
▬ Tooth resorption rare
▬ T1-weighted MRI: intermediate signal
▬ T2-weighted MRI and STIR: heterogeneous low signal
▬ T1-weighted MRI: contrast enhancement

75. Fibrous dysplasia and ossifying fibroma share overlapping histologic features, making the
differential diagnosis challenging, particularly when biopsy does not achieve an adequate
sample. Some imaging findings may be helpful for the characterization of the lesion (Fig. 23).

78. Metastasis
 Rarely, the nose and Paranasal sinus are the site of a
distant metastasis, mostly of renal cell, breast or lung
carcinoma.
 Signs and symptoms are similar to those caused by benign
and malignant lesions.
 Imaging appearance is nonspecific, although intense
enhancement is expected in hypervascular metastases,
such as those produced by renal cell carcinoma and
melanoma.
 Maxillary sinus (33%) is the most commonly involved site
followed by sphenoid sinus (22%), ethmoid (14%) and
frontal sinus (9%); simultaneous involvement of more than
one cavity occurs in as many as 22% of cases.

81. TRAUMA
CT is the superior imaging modality to assess bone structures and routinely the
examination will include axial and coronal sections.With multidetector CT, high-quality
images can be obtained in any desired plane and 3D reconstruction can be very
valuable in the evaluation of the complex facial skeleton.

83. The buttress system of the midface.
The buttress system of the midface is formed by the strong frontal, maxillary, zygomatic,
and sphenoid bones and their attachments to one another.
The central midface consists of several fragile bones that easily ‘‘crumple’’ when
subjected to strong forces. These more fragile bones are surrounded by the thicker
bones of the buttress system, which provide structure and absorb the forces applied to
the face. Most of the forces absorbed by the face are masticatory, therefore the vertical
buttresses are the most well developed. These include the medial nasomaxillary buttres
and the lateral zygomaticomaxillary buttress. Three horizontal buttresses interconnect
and provide support for the vertical buttresses: the frontal bone and supraorbital rims
(frontal bar), the nasal bones and inferior orbital rims, and the maxillary alveolus. (From
Linnau KF, Stanley RB Jr, Hallam DK, et al. Imaging of high-energy midfacial trauma: what
the surgeon needs to know. Eur J Radiol 2003;48:17–32;
with permission.)

84. Fractures
Definition
Traumatic cortical discontinuity with or without dislocation
Clinical Features
▬ See Non-fracture Traumas
▬ Abnormal morphology such as
flattening
▬ Palpable step-off of bone
▬ Crepitation due to emphysema
▬ Paresthesia, anesthesia
▬ Hemorrhage
Imaging Features
▬ See Non-fracture Traumas
▬ Cortical discontinuity, defect
▬ Abnormal angulation
▬ Absent or displaced bone
▬ Abnormal linear density
▬ Bone overlap (“double
radiopacity”)
▬ Green-stick in young patients
▬ “Empty fossa” sign on axial CT
images
▬ Localized air collection

86. LeFort Fractures
Definition
LeFort 1 is characterized by fracture just above the floor of the nasal cavity with
separation of the entire palate and maxillary alveolar process; fractures through the
lower nasal septum, lower walls of maxillary sinuses, and lower pterygoid plates
(“horizontal fracture”). “Floating palate” (LeFort 1)

88. LeFort 2
Characterized by fracture of the root of the nose, bilateral fractures of
the lacrimal bones and medial orbital walls, the floor of the orbits near
the infraorbital canals, zygomaticomaxillary sutures and anterior walls of
maxilla (“pyramidal fracture”) and posteriorly, infratemporal surfaces of
the maxilla and lower pterygoid plates.
Wassmund 1 fracture does not include the nasal bones but is otherwise
identical.
“Dish face”, hemorrhage, edema, emphysema, and in near 80%
anesthesia of infraorbital nerve(s) (LeFort 2)

90. LeFort 3
characterized by separation of the entire viscerocranium from
the skull base (“craniofacial dysjunction”); fracture of the root
of the nose, bilateral fractures of the lacrimal bones and
medial orbital walls, the floor of the orbits to the inferior
orbital fissure,where one fracture line extends to the lateral
orbital wall and another down across the posterior maxilla to
the lower pterygoid plates and additionally, fractures of the
zygomatic arches. Wassmund 3 fracture does not include the
nasal bones but is otherwise identical.
“Dish face”, CSF rhinorrhea, hemorrhage, edema,
emphysema, damage to lacrimal apparatus, and in near 70%
anesthesia of infraorbital nerve(s) (LeFort 3)

92. Tripod Fracture
Synonyms: Trimalar or zygomatic fracture
Definition
Fracture through
(1) lateral orbital wall with fracture site at zygomaticofrontal suture,
(2) zygoma and maxilla with fracture site at zygomaticomaxillary
suture,
(3) zygomatic arch with fracture site at zygomaticotemporal suture.
Clinical Features
▬ Most common fracture of facial skeleton after nasal and mandibular
fractures
▬ About half of all midfacial fractures (more than two-thirds in one
study), either alone or in combination with other midfacial fractures
▬ Infraorbital nerve paresthesia or anesthesia in almost 95%

95. Blow-out Fracture
Definition
Fracture of orbital floor, usually not orbital rim (classic); but also of medial or
other orbital walls.
Clinical Features
▬ Only 3–5% of all midfacial fractures
▬ Diplopia
▬ Enophthalmos, exophthalmos

99. Acute Rhinosinusitis
Definition
Acute inflammation in nose and paranasal sinuses.
Clinical Features
▬ One of most common medical afflictions.
▬ Viral rhinosinusitis most common (common cold, influenza).
▬ Bacterial rhinosinusitis may develop secondarily (Haemophilus
influenzae, Streptococcus pneumoniae).
▬ Pain over sinuses; cheek, frontal, between eyes, or suboccipital.
▬ Toothache, teeth tenderness to percussion; more than one tooth of
maxillary lateral segment(s).
▬ Headache seldom.
▬ Dental etiology in 10–20%; larger frequencies have been reported
depending on patient materials.

100. Imaging Features
▬ Nodular or smooth mucosal thickening or complete sinus
opacification
▬ Contrast-enhanced inflamed mucosa lining; variable
amounts of submucosal edema and surface secretions
▬ Air-fluid level, most frequent in maxillary sinus, due to
bacterial sinusitis with obstruction of ostium, but only in 25–
50% of patients with this disease
▬ T1-weighted MRI: low to intermediate
▬ T2-weighted MRI: high signal of inflamed mucosa and
fluid
▬ T1-weighted post-Gd MRI: intense enhancement of
inflamed mucosa; no enhancement of fluid

104. Chronic Sinusitis
Definition
Develops from either persistent acute inflammation
or repeated episodes of acute or subacute sinusitis.
▬ Allergic sinusitis
▬ Vasomotor rhinitis
▬ Fungal sinusitis (90% Aspergillus fumigatus; may
be fulminant and invasive in immunosuppressed
patients)
Clinical Features
▬ Anaerobic microorganisms frequently isolated

105. Imaging Features
▬ Varying mucosal swelling, smooth or irregular swelling due to edema
and secretion.
▬ Thickened, sclerotic, fibrotic sinus walls, particularly of maxillary
sinuses.
▬ Dystrophic calcification.
▬ T1-weighted MRI: low to intermediate.
▬ T2-weighted MRI: usually high signal of inflamed mucosa, low signal
of sclerosis and fibrosis. Inspissated mucus can be dark on all sequences
resulting in false-negative MR diagnosis of chronic sinusitis

110. Mucosal Imaging Findings in Asymptomatic Individuals
MRI findings of paranasal sinuses in patients with brain imaging.
▬ Mucosal thickening up to 3 mm may be present in clinically normal
individuals.
▬ Clinically silent focal areas of mucosal thickening occur from about
one-fourth and up to two-thirds of asymptomatic individuals.
Retention Cysts,Mucous and Serous
Definition
Mucous retention cyst: obstruction of submucosal mucinous gland, thus
cyst wall of duct epithelium and gland capsule. Serous retention cyst:
accumulation of serous fluid in submucosal layer of sinus mucosa, thus
cyst lining of elevated mucosa.

111. Imaging Features
▬ Smooth, spherical soft tissue mass.
▬ Retention cysts found incidentally in 10–35% of patients,
most commonly in maxillary sinus, but
can occur in any sinus.
▬ Frequently small, may become large but always
some air.
▬ Almost in every case normal bone.
▬ T1-weighted MRI: usually low to intermediate signal, but
may show high signal if cyst has high
protein content.
▬ T2-weighted MRI: high signal

113. Polyps
Definition
Expansion of fluids in deeper lamina propria of Schneiderian mucosa in nasal fossa and
paranasal sinuses.
Clinical Features
▬ Most common expansile condition in nasal cavity; about 4% in general population.
▬ Nasal polyps most often associated with allergy, and frequently multiple and symmetric,
but may result from infectious rhinosinusitis, vasomotor rhinitis, cystic fibrosis, diabetes
mellitus, aspirin intolerance, and nickel exposure.
▬ In patients with polyps up to about 70% with asthma.
▬ Nasal stuffiness.
▬ When seen in children, cystic fibrosis should be ruled out.
Imaging Features
▬ Smooth, spherical soft tissue mass
▬ If multiple, complete opacification of nasal cavity and sinuses
▬ T1-weighted MRI: low to intermediate signal
▬ T2-weighted MRI: high signal
▬ Heterogeneous MR signal characteristic in chronic polyps; can also enhance

118. Mucoceles
Definition
Collection of mucoid secretions surrounded by mucus-secreting respiratory
epithelium.
Both retention and mucocele cysts consist of mucous secretions surrounded by
epithelial lining, but are distinguished by their clinical and imaging features.
Mucocele develops due to obstruction of sinus ostium or a compartment of a
sinus with the sinus mucosa as the mucocele wall and always with expandedsinus
walls.
Clinical Features
▬ Most common expansile condition in paranasal sinuses.
▬ Most frequent in frontal sinuses (60–65%); only 5–10% in sphenoid as well as
in maxillary sinuses.
▬ Both sexes,wide range of age: 20 to 60 years.
▬ Classic mucocele is sterile with signs and symptoms from mass effect.
▬ Pain uncommon.
▬ If infected, pain; mucopyocele or pyocele.
▬ Ostial obstruction may be caused by inflammatory scar, trauma, or tumor.

119. Imaging Features
▬ Initially, intact but remodeled, expanded surrounding
bone.
▬ With progressive growth sinus wall will be destroyed.
▬ Completely airless sinus.
▬ T1-weighted and T2-weighted MRI: variable MR signals
depending on protein content, state of dehydration, and
viscosity of content; most frequently observed patterns are
moderate-to-marked high signal on T1 and T2, or moderateto-marked
low signal on T1 and T2, usually low to intermediate T1 and
high T2.
▬ T1-weighted post-Gd MRI: no enhancement except of thin
peripheral rim.