Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_4548_Библиотеки_им_академика_М_И_Перельмана

Good radiology, better-quality visualization, advances in technology and in-depth anatomical knowledge allows removal of central skull base lesion by transnasal route. CECT and MRI scan in all planes at 1mm interval is required to map the extent of the lesion. The diagnostic cerebral angiography (DSA) is indicated in selected cases, to obtain information regarding vascularity of the lesion and possible involvement of surrounding major neurovascular bundle. Extended endo­scopic approaches are divided into median and paramedian type. Median approaches are for midline lesions. It is further divided on the basis of site of involvement such as frontal sinus, crib­riform plate, planum sphenoidalis, etc. Paramedian approaches are for lateral lesions. It is further divided into anterior, middle and poste­rior approaches. Intraorbiral and transorbital comes under the anterior subtype. Cavernous sinus, petrous apex and infratemporal area lesions are managed by the middle approach. Condylar, hypoglossal canal and jugular fossa lesions are delt by posterior approach. Pituitary gland lies behind and above the sphenoid sinus. Number of hormones are secreted by the pituitary gland. Pituitary adenomas are dealt by both medical and surgical ways. These adenomas are the most common lesions managed by extended endo­scopic approaches. Tumours involving the skin, extending beyond the mid-pupillary line, tumour inltration into the orbital tissue and palatal bone erosion are the indications for open approaches. Open extra-cranial approaches are further subdi­vided into soft tissue and bony approaches. Moure’s Lateral Rhinotomy Incision and Weber– Ferguson incisions are the most commonly used soft tissue approaches. Transcranial approaches to the anterior skull base are divided into anterior and anterolateral approaches depending upon the tumour extensions. The lacrimal system is for sucking the tears. The obstruction of nasolacri­mal duct requires the creation of new communi­cation between the sac and nasal cavity. Dacryocystorhinostomy is of two types: endo­scopic and external. The endoscopic method pro­vides almost equal results with an open approach. The endoscopic approach is devoid of complica­tions of external approach such as lacrimal pump

Extended endoscopic endonasal approaches (EEAs) have come up as a good substitute to tra­ditional open approaches. Advance technology allows superior visualization and better control of instruments with precision in disease clear­ance. The extent of EEAs is from cribriform plate to clivus and C2 vertebrae. The major drawback of open approaches is the manipulation of the cerebrum, blood vessels and cranial nerves. The other disadvantages of traditional approaches are

(A) Transfrontal Approach (Fig. 7.2)

(i) Debulking of intranasal mass may

(vi) Dura mater is cauterized peri-

(vii) The nal defect is from the median