We can classify anterior skull base approaches according to bone flap size into macrocraniotomy and minicraniotomy approaches. Macrocraniotomy approaches like the bifrontal, bicoronal, orbitozygomatic, and classic pterional approaches. Minicraniotomy approaches like the supraorbital keyhole approach. The bifrontal and bicoronal approaches are time consuming, extensive with complications related to large craniotomy flap, more blood loss, superior sagittal sinus violation, frontal air sinus opening leading to postoperative CSF leak, and postoperative behavioral changes from brain edema of bilateral brain retraction. They are sometimes associated with bad cosmetic results. The classic pterional approach of Yasargil was associated with temporalis muscle atrophy leading to postoperative mastication problems and bad cosmetic outcome due to complete subperiosteal temporalis dissection beside the risk of injury of frontotemporal branch of facial nerve [10,11,12,13].
Minicraniotomy approaches like the supraorbital keyhole approach had some limitations such as difficult application for vascular lesions due to difficult proximal control, impossible to operate in case of intraoperative aneurysm rupture, or brain swelling which occlude the surgical field. Also, difficulty to perform on large-sized neoplastic lesions, Hammad et al. operated on 22 patients in Ain Shams University, Egypt. They used the keyhole approach only in tumor sizes less than 4 cm. The eyebrow incision used frequently in this approach is historically associated with loss of supraorbital sensation or palsy of frontal branch of facial nerve [14, 15].
We operated on 50 patients having anterior skull base lesions (16 vascular and 34 neoplastic) through the lateral supraorbital approach, a medium-sized approach, more sub-frontal, and less temporal exposure. This approach is a less extensive modification of the classic pterional approach. The craniotomy size was fair enough to decrease the risk of large craniotomy associated problems but at the same time sufficient to reach the entire anterior skull base .
Incomplete clipping was done in one bilobed AcoA aneurysm where there was remnant neck; another surgery was performed, and one more clip was applied. Subtotal resection was done in 5 tumors (2 craniopharyngiomas, 2 tuberculum sellae meningiomas, and one olfactory grove meningioma). This was not related to operating through the lateral supraorbital approach neither for vascular nor large neoplastic lesions. We believe that many other factors had affected the surgical outcome such as aneurysm morphology, tumor consistency, anatomical extension, and attachment to neurovascular structures.
Mean flap size in our series was 3.5 × 5.4 cm while in the series of Prof. Hernesneimi it was 3 × 5 cm because in the early beginning we used larger flaps due to lack of confidence and need of assistant hand in the field especially in aneurysm cases. In large-sized tumors, we preferred to extend the bone flap 1 cm posteriorly [8, 9, 13].
The lateral supraorbital approach takes short time; this shortens the overall operative time. Mean approach time in our series was 20 min while in the series of Prof. Hernesneimi it was 14 min because he is a well-known fast surgeon; he has some facilities that saves the time needed for hemostasis as the Sugita frame used for head fixation with strong fishhook retractors, using rani clips in skin edge hemostasis and fibrin glue in epidural space hemostasis [8, 9, 13].
We had one case of postoperative CSF rhinorrhea that stopped spontaneously. One case had subcutaneous CSF collection that disappeared after single tapping and bandage. One case had periorbital edema that subsided spontaneously, and one diabetic case had superficial wound infection that improved with daily dressing and antibiotics.
The cosmetic results were assessed according to the patient and surrounding personnel opinion in follow-up visit despite depending on cultural background and expectation before surgery; the scar was accepted in all patients.
We used a curvilinear skin incision situated behind the hair-line (better for healing and can be sutured intradermally with small invisible linear scar) with better cosmetic results. The skin incision stops 1 cm above the zygoma with less trauma to temporalis muscle. The frontotemporal branch of the facial nerve is safe in this approach because we do not do superficial dissection. The temporalis muscle is split only in its anterior and superior parts, which decreases the incidence of postoperative temporalis wasting and mastication problems. Our cosmetic results were similar to Prof. Hernesneimi because we used the same technique. We did not use the eyebrow incision, which is historically associated with loss of supraorbital sensation or palsy of frontal branch of facial nerve. Beseoglu et al. had a series of 54 patients operated through the supraorbital keyhole approach reported. Forty-nine (90.7%) rated the cosmetic results as very good or good, and 5 patients had bad outcome [12, 17, 18].
Sánchez-Vázquez et al. reported hypesthesia of the frontal region appeared in all patients; however, it disappeared completely in all patients as early as the 2nd month after surgery. Inability to raise the eyebrow immediately after surgery was a complaint in all patients; however, in five, the defect disappeared during the 1st month after surgery; in eight others, it disappeared after the 2nd month, and in the remaining patients, it disappeared completely after the 3rd month following surgery .
All morbidities and mortalities in our approach were related to lesion pathology or clinical condition of our patients, and there were no approach-related morbidities or mortalities.
The lateral supraorbital approach cannot be done in the presence of angry brain with high intracranial pressure so we paid all efforts to have a slack brain from perfect positioning, perfect neuroanasthesia, and CSF release either from the lumbar subarachnoid space or basal cisterns with minimal brain retraction. The Sylvian fissure appears at the posterior edge of the dural flap and can be easily opened when necessary [8, 9, 13].