PARANASAL SINUSES

CT has become a useful diagnostic modality in the evaluation of the paranasal sinuses and an integral part of surgical planning. It is also used to create intraoperative road maps.

The use of CT scanning combined with functional endoscopic sinus surgery (FESS) has empowered the modern sinus surgeon

SINUSITIS

Sinusitis (or rhinosinusitis) is defined as an inflammation of the mucous membrane that lines the paranasal sinuses

due to infection, allergy, or autoimmune issues.

FUNGAL SINUSITIS

WHAT IS A FUNGUS ?

Fungi are plant-like organisms that lack chlorophyll fungi must absorb food from dead organic matter. Fungi are supposed to "eat" only dead things, but sometimes they start eating when the organism is still alive.

Fungi share with bacteria the important ability to break down complex organic substances of almost every type (cellulose) and are essential to the recycling of carbon and other elements in the cycle of life.

CANCER

Paranasal sinus and nasal cavity cancer is a disease in which malignant (cancer) cellsform in the tissues of the paranasal sinuses and nasal cavity.

The most common type of paranasal sinus and nasal cavity cancer is squamous cell carcinoma.

Melanoma : The cells that give skin its natural color. Sarcoma : Cancer that starts in muscle or connective tissue Inverting papilloma : Benign tumors that form inside the nose Midline granulomas : Cancer of tissues in the middle part of the face

How paranasal sinus cancer is diagnosed

X-rays These may be taken to show the size and position of the cancer, and to check the bones of the face.

CT (computerised tomography) scan A CT scan takes a series of x-rays that build up a three-dimensional picture of the inside of the body. The scan is painless and takes 10-30 minutes.

MRI (magnetic resonance imaging) scan This test is similar to a CT scan but uses magnetism instead of x-rays to build up a detailed picture of areas of your body.

Nasopharyngoscopy

During this procedure a fine tube with a light at the end (nasendoscope) is guided through the nose into the sinus area.

TNM staging The most commonly used staging system is called the TNM system:

T refers to the size or position of the primary tumour (where the cancer first starts in the body). N refers to which lymph nodes are affected, if any M refers to metastatic disease

Cancer stage grouping

Stage 0:This is a very early cancer (Tis) with no spread to lymph nodes (N0) or distant metastasis (M0).

Stage I:This is a noninvasive cancer (T1) with no spread to lymph nodes (N0) and no distant metastasis (M0)

Stage II:This is an invasive cancer (T2) that has not spread to lymph nodes (N0) or to distant parts of the body (M0).

Stage III:This includes invasive cancer (T3) with no spread to regional lymph nodes (N0) or metastasis (M0), as well as invasive cancer (T1, T2, T3) that has spread to regional lymph nodes (N1) but shows no sign of metastasis (M0).

Stage IVA:This is an invasive cancer (T4a) that either has no lymph node involvement (N0) or has spread to only one same-sided lymph node (N1) but with no metastasis (M0). It is also used for any cancer (any T) with more significant nodal involvement (N2) but with no metastasis (M0).

tage IVB:This is an invasive cancer (any T) that has spread to lymph nodes (any N) but has no metastasis (M0). It is also used for any cancer (any T) that is found in lymph nodes and is larger than 6 cm (N3) but has no metastasis (M0).

Stage IVC:This refers to any tumor (any T, any N) when there is evidence of distant spread (M1).

RadiographyCTBony erosionLimitations with periorbita involvementMRI94 -98% correlation with surgical findingsInflammation/retained secretions: low T1, high T2Hypercellular malignancy: low/intermediate on bothEnhancement with Gadolinium

Staging of Maxillary Sinus TumorsT1: limited to antral mucosa without bony erosionT2: erosion or destruction of the infrastructure, including the hard palate and/or middle meatusT3: Tumor invades: skin of cheek, posterior wall of sinus, inferior or medial wall of orbit, anterior ethmoid sinusT4: tumor invades orbital contents and/or: cribriform plate, post ethmoids or sphenoid, nasopharynx, soft palate, pterygopalatine or infratemporal fossa or base of skull

SurgeryUnresectable tumors:Superior extension: frontal lobesLateral extension: cavernous sinusPosterior extension: prevertebral fasciaBilateral optic nerve involvement

Current indications for orbital exenterationInvolvement of the orbital apexInvolvement of the extraocular musclesInvolvement of the bulbar conjunctiva or scleraLid involvement beyond a reasonable hope for reconstructionNon-resectable full thickness invasion through the periorbita into the retrobulbar fat

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