الفهرس 
Anatomy of skull base:
Internal carotid artery (ICA):Only 14 pages are availabe for public view
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Abstract
Juvenile nasopharyngeal angiofibroma is a highly vascular, benign but locally aggressive tumor affecting young adolescents with exclusive male predominance. It originates in the nasopharynx near the sphenopalatine foramen and may then extend to the nasal cavity, paranasal sinuses, infratemporal fossa, orbit and intracranially. Affected patients usually present with recurrent painless epistaxis, nasal obstruction and discharge. Facial swelling, proptosis, diplopia, cranial nerve palsy may develop at later stages. Diagnosis is based upon clinical suspicion in the specific population. Unfortunately, clinical examination doesn‘t add much to diagnosis in the early stages of the disease. Endoscopy would reveal a nasopharyngeal mass. Taking biopsy from JNA is considered risky and should be avoided. Imaging is the clue to such diagnostic dilemma due to its characteristic findings. CT and MRI show a mass with typical location at the sphenopalatine foramen, widening of the PPF and having variable degrees of extension. It shows intense enhancement after IV contrast administration. Catheter angiography accurately delineates the arterial supply for the mass, which is essential for operative approach planning. Surgery, either open or endoscopic, remains the treatment of choice. But the associated potentially fatal intraoperative hemorrhage and the risk of postoperative complications are the main drawbacks of open surgery. Endoscopic surgery is being more widely employed in JNA surgery, with less bleeding and less postoperative complications. Other treatment options underwent trials in the past, but were ineffective or with inferior results to surgery. Those include chemotherapy, hormonal therapy or radiotherapy. Multiple options have been explored to reduce intraoperative blood loss, including external carotid ligation and preoperative embolization. The aim of this study was to evaluate the impact of preoperative embolization of Juvenile Nasopharyngeal Angiofibroma on the surgical outcome (Including intraoperative blood loss & amount of blood transfusion). Patients and Methods: In this study, 20 male patients with JNA underwent preoperative transarterial angiography and embolization 1-3 days prior to surgery. The embolization procedures were carried out at Department of Interventional Radiology, Cairo University, Cairo, Egypt. While surgery was carried out at the Department of Otolaryngology and Head and Neck Surgery, Cairo University, Cairo, Egypt. All patients were subjected to: 1- Full history taking. 2- General and local examination. 3- Pre procedure laboratory and imaging investigations. 4- Transarterial angiography and embolization procedure of the tumor‘s supplying arteries. 5- The patients then underwent surgery, either open or endoscopic, and their operative data was recorded. Evaluation of the effect: It was done by: Evaluation of effect of angiography and embolization: 1- Determination of supplying and embolized arteries. 2- Whether ICA is contributing to the tumor supply or not. 3- Percent residual tumor blush after embolization. 4- Any complication encountered due to angiography or embolization. Evaluation of surgical outcome: 1- Operative approach used. 2- Amount of intraoperative blood loss. 3- Amount of intraoperative blood transfusion. Different correlations were made between blood loss and various other parameters e.g. tumor supplying vessels, tumor residual blush, operative approach used… etc. The results of this study are summarized as following: According to University of Pittsburg Medical Center (UPMC) for staging of JNA, this study included 5 patients (25%) with stage I, 3 patients (15%) with stage II, one patient (5%) with stage III, 7 patients (35%) with stage IV and 4 patients (20%) with stage VM (medial extension). The angiography and embolization procedures were technically successful in all included patients. Polyvinyl Alcohol (PVA) particles were used in all patients, while microcoils were used in 1 patient. Either general anesthesia or conscious sedation was used according to the patient age and cooperation. No intraprocedural or neurological complications were encountered. Minor post procedure complications were encountered in 6 patients (30%) and were managed successfully by medical treatment. Those complications included groin pain, facial pain, headache and hematoma at the groin puncture site. Surgery was done at a mean of 35.4 hours after embolization. 13 patients (65%) underwent pure endoscopic surgery, 4 patients (20%) underwent open surgery, and 3 patients (15%) underwent combined open and endoscopic surgery. The mean intraoperative blood loss for all procedures in this study was 665 ml. The mean intra operative blood loss for endoscopically performed procedures was 388.46 ml compared to 1275 ml for surgical procedures. While for combined surgical and endoscopic procedures, the mean intraoperative blood loss was 1050 ml. In the current study, only 7 patients (35%) required blood transfusion. The mean amount of blood transfusion was 928.57 ml. Transfusion was required only in procedures performed in advanced stages of the tumor (UPMC stage VI and V). Also, transfusion was required in some open or combined procedures, but none of the endoscopic procedures. There was a significant negative correlation between endoscopic use and the amount of intraoperative blood loss. Also, a significant correlation was found between the amount of blood loss and ICA tumor supply, UPMC staging of the tumor and residual tumor blush. Various vascularization patterns were found depending upon the stage and direction of tumor spread. The most common pattern was the isolated ipsilateral ECA supply, found in 9 patients (45%). Vascular supply from the ipsilateral or contralateral ICA or ECA in addition to the ipsilateral ECA was found in differing proportions. The Ipsilateral internal maxillary artery was found to supply the tumor in all cases (100%), followed by ipsilateral ascending pharyngeal artery in 13 patients (65%). Other ipsilateral or contralateral branches may be involved according to tumor pattern of spread. ICA supply of the tumor was seen in 11 patients (55%). The vidian artery is the most involved ICA branch in JNA supply, found in 10 out of 11 patients (90.1%). Other involved ICA branches include the artery of foramen rotundum, ophthalmic artery and meningohypophyseal trunk. Complications were encountered in 6 patients (30%). These included groin pain in 2 patients (10%), facial pain in 2 patients (10%), headache in 1 patient (5%) and groin hematoma in 1 patient (5%). However, they were minor and treated medically with no need for surgical intervention or leaving permanent sequelae. None of the patients experienced major complications, stroke, blindness or necrosis of skin or soft tissue of the face as previously reported in some literature. Epistaxis was found to be the most common presenting symptom, affecting 17 patients (85%), followed by nasal obstruction in 16 patients (80%). Other symptoms included rhinorrhea, headache & facial pain, proptosis, diplopia, nasal mass, facial swelling, recurrent otitis media.