Lateral Supraorbital Approach Research Articles

Microscopic and endoscopic anterior communicating artery complex anatomy as seen through keyhole approaches

The purpose of this anatomical study is to illustrate the microscopic and endoscopic anatomy of the anterior communicating artery complex as viewed through three keyhole approaches (keyhole pterional, lateral supraorbital and supraorbital) and to compare them. Each approach was carried out once on each side in five glutaraldehyde-fixed human cadaveric heads. A microscope and microscope–endoscope combination were used to grade access and visualization of the structures qualitatively using a previously published surgical exposure grading system. All three approaches provided good access and visualization of ipsilateral structures in the anterior communicating artery complex, but the pterional keyhole and the lateral supraorbital approaches gave the best access. Exposure of contralateral structures was limited overall, but was enhanced somewhat by the use of the endoscope.

A New Methodology for Laboratory Evaluation of Neurosurgical Approaches Based on the Volume and Shape of the Surgical Space with a Mathematical Model to Quantify the Surgical Maneuverability in Laboratory Settings

We conducted this study to validate the volume/shape of the surgical exposure and to introduce a mathematical model to quantify the maneuverability in a surgical space. We executed the pterional and lateral supraorbital approach four times in fresh cadavers in skull base laboratory. The surgical volumes were filled with a computed tomography (CT)-imageable mixture; CT scans were obtained to evaluate the volume and shape of the surgical space. The volume of the surgical space was 23.60 and 32.90 mL for the lateral supraorbital and pterional approach, respectively, (p < 0.05). The three-dimensional shape of the lateral supraorbital approach was cylindrical and that of the pterional approach pyramidal. The volume of the surgical approach can be used to define, together with other variables, the maneuverability (maneuvering in a surgical volume) by using the following formula [Formula: see text] where M, A, V, and L represent the maneuverability, the degree of the surgical freedom, the volume of the surgical exposure, and the surgical depth, respectively. Volume and shape of the surgical exposure are two objective parameters that can be used to define and contrast different microsurgical approaches in a laboratory setting. The volume of the surgical exposure may be integrated into a mathematical formula defining maneuverability.

Lateral Supraorbital Approach Applied to Tuberculum Sellae Meningiomas

Various surgical approaches for the removal of tuberculum sellae meningiomas (TSMs) have previously been described. To assess the reliability and safety of the lateral supraorbital (LSO) approach to remove TSMs. We identified all TSM patients operated on at the Department of Neurosurgery at Helsinki University Central Hospital, Finland, by the senior author (J.H.) using the LSO approach between September 1997 and August 2010. We retrospectively analyzed the clinical data, radiological findings, surgical treatment, histology, and outcome of patients and discuss the operative technique. Apparent complete tumor removal was achieved in 45 patients (87%). Of 42 patients, preexisting visual deficit improved in 22, remained the same in 13, and worsened in 7, and de novo visual deficit occurred in 1 patient. At 3 months post-discharge, 47 patients (90%) had a good recovery, 4 (8%) were moderately disabled, and 1 (2%) died 40 days after surgery of unexplained cardiac arrest. Seven patients (13%) had minimal residual tumors, 2 of which required reoperation. During the median follow-up of 59 months (range, 1-133 months), tumor recurred in 1 of the patients who had undergone a second operation. TSMs of all sizes can be removed via the LSO approach with minimal morbidity and mortality. Low-power or no coagulation is recommended near the optic nerves and the optic chiasm to preserve their vascular support from the internal carotid artery perforators. Our results are comparable to those obtained using more extensive and time-consuming approaches. We recommend the LSO approach to remove TSMs.

Comparison between Lateral Supraorbital Approach and Pterional Approach in the Surgical Treatment of Unruptured Intracranial Aneurysms

ObjectiveThe lateral supraorbital (LSO) approach is a modified method of the classic pterional approach and it has advantages of short skin incision and small craniotomy compared with the pterional approach. This study was designed to compare the two approaches in the surgical treatment of unruptured intracranial aneurysms.MethodsWe retrospectively reviewed 122 patients with 137 unruptured intracranial aneurysms treated by clipping, from July 2009 to April 2011. Between August 2010 and April 2011, 61 patients were treated by clipping via the lateral supraorbital approach and the same number of patients treated by clipping via the pterional approach were retrospectively enrolled. We analyzed the two groups and compared demographic, radiologic and clinical variables.ResultsThe mean age of patients in the two groups was 54.6 years (LSO group) and 55.7 years (Pterion group). The mean duration of hospitalization was shorter in the LSO group than in the Pterion group (7.9 days vs. 9.0 days, p=0.125) and the mean operation time was also significantly shorter in the LSO group (117.1 minutes vs. 164.3 minutes, p<0.001). Furthermore, the mean craniotomy area was much smaller in the LSO group (1275.4 mm2 vs. 2858.9 mm2, p<0.001). The two groups showed similar distributions of aneurysm location and postoperative complications.ConclusionThe lateral supraorbital approach for the clipping of unruptured intracranial aneurysm could be a good alternative to the classic pterional approach.

Benefits of early aneurysm surgery: Southern Iran experience

Background:Neurovascular surgery has been practiced in Shiraz, the main referral center of the Southern Iran, for over 30 years; however, the trend has accelerated tremendously in recent years following subspecialization of neurovascular surgery in Shiraz, Department of Neurosurgery. Over 100 patients are operated each year, and nearly all are addressed during the first 72 hours after presentation.Methods:In this paper, we focus on the description of techniques we apply for early clipping of ruptured intracranial aneurysms in the anterior circulation. Improvements in outcome, mortality, and rebleeding rates are also discussed.Results:Mortality and rebleeding rates have declined significantly since the institution of new techniques.Conclusion:The establishment of early surgery for ruptured anterior circulation aneurysms through the lateral supraorbital approach along with specific anesthetic protocol has resulted in significant improvement of morbidity, mortality, and rebleeding rates at our department.

Lateral Supraorbital Approach vs Pterional Approach: An Anatomic Qualitative and Quantitative Evaluation

Several minimally invasive modifications of the standard pterional approach have been proposed recently. The lateral supraorbital approach is one of these modifications. To provide a qualitative and quantitative anatomic comparison of the surgical exposure and the operability afforded by the standard pterional approach and the lateral supraorbital approach. Eight pterional approaches and 8 lateral supraorbital approaches were used in 8 fresh human cadaver heads. One qualitative and 2 quantitative tools were used to assess the surgical exposure. Qualitatively, the lateral supraorbital approach has the advantages of reduced trauma to the temporalis muscle and exposure that is comparable to that provided by the standard pterional approach to the sellar and suprasellar regions. This approach offers limited exposure of the interpeduncular fossa compared with the pterional one. Quantitatively, the pterional approach provides a greater surgical volume than the lateral supraorbital approach (32.90 mL vs 23.60 mL with P < .05). Also, the pterional approach provides a greater associated surgical operability than the lateral supraorbital approach (exposure score of 66 and 53, respectively). However, the lateral supraorbital approach offers an equivalent access to the anterior communicating artery complex, optic nerve, optic chiasm, and sellar area (the exposure scores were 19 for both approaches). From an anatomic point of view, both approaches provide similar exposure to the sellar, suprasellar, and anterior communicating artery areas. The pterional approach provides better exposure of the retrosellar area. The ability to operate in the retrosellar area, as judged by our model, was higher with the pterional than with the lateral supraorbital approach.

Lateral Supraorbital Approach Applied to Anterior Clinoidal Meningiomas: Experience With 73 Consecutive Patients

Anterior clinoidal meningiomas (ACMs) are a subgroup of meningiomas accounting for less than 10% of supratentorial meningiomas. To assess the reliability and safeness of the lateral supraorbital approach (LSO) to remove ACMs. Between September 1997 and October 2009, a total of 73 ACM patients were operated on at the Department of Neurosurgery, Helsinki University Central Hospital, by the senior author (J.H.). We retrospectively analyzed the clinical data, radiological findings, surgical treatment, histology, and outcome of patients, and discuss the operative technique. Seventy-three patients were operated on by applying the LSO approach. Apparently complete removal was achieved in 57 patients (78%). Anterior clinoidectomy was performed in 21 cases. Preexisting visual deficit improved in 11 of 39 patients and worsened in 4; 3 had de novo visual deficit. At 3 months after discharge, 60 (82%) patients had a good recovery, 9 (12%) patients were moderately disabled, 1 presented with severe disability, and 3 (4%) patients died of surgery-related causes. Sixteen (22%) patients had residual tumors, 6 of which required reoperation. During the median follow-up of 36 months (range, 3-146), tumor recurred in 3 patients: 2 were followed-up and 1 was reoperated on. ACMs can be removed via the LSO approach with relatively low morbidity and mortality. Anterior clinoidectomy is required only in selected cases, and we prefer the intradural approach during the LSO approach. High-power coagulation should be avoided in proximity of the optic nerve.

Slack brain in meningioma surgery through lateral supraorbital approach

Background:Surgery of skull base meningiomas by the lateral supraorbital (LSO) approach requires relaxed brain. Therefore, we assessed combined effects of the elements of neuroanesthesia on neurosurgical conditions during craniotomy.Methods:The anesthesiological and surgical charts of 66 olfactory groove, 73 anterior clinoidal, and 52 tuberculum sellae meningioma patients operated on by the senior author (J.H.) at the Department of Neurosurgery of Helsinki University Central Hospital, Helsinki, Finland, between September 1997 and August 2010, were retrospectively analyzed.Results:One-hundred fifty-four (82%) patients had good surgical conditions, and this was achieved by (1) elevating the head 20 cm above the cardiac level in all patients with only slightly lateral turn or neck flexion, (2) administering mannitol preoperatively in medium or large meningiomas (n = 60), (3) maintaining anesthesia with propofol infusion (n = 46) or volatile anesthetics (n = 107) also in patients with large tumors (n = 37), and (4) controlling intraoperative hemodynamics. Brain relaxation was satisfactory in 18 (10%) and poor in 15 (8%) patients. The median intraoperative blood loss was 200 (range, 0-2000) ml. Only 9% of patients received red blood cell transfusion. The median time to extubation was 18 (range, 8-105) min after surgery. Extubation time correlated with the patients’ preoperative clinical status and the size of tumor but not with the modality of anesthesia.Conclusions:Slack brain during the LSO approach is achieved by correct patient positioning, preoperative mannitol, either by propofol or in small tumors inhaled anesthetics, and optimizing cerebral perfusion pressure. Under these circumstances, intraoperative brain swelling is prevented, bleeding is minimal, and no blood transfusions are needed.

REPAIR OF AN ALARMING INTRAOPERATIVE INTRACAVERNOUS CAROTID ARTERY TEAR WITH ANASTOCLIPS

Surgical treatment of an intracavernous carotid aneurysm (ICCA) is difficult because of the close relationship to bone, dura, and neurovascular structures. Intraoperative rupture of an ICCA is challenging, especially if the site of rupture is at the base of the aneurysm. We present a case of intraoperative rupture of an ICCA caused by clinoidectomy. We repaired it by using a single-clamp applicator (AnastoClip Vessel Closure System, 1.4 mm; LeMaitre Vascular, Burlington, MA). In April 2007, a 40-year-old woman underwent neurosurgical treatment at another institution for a ruptured basilar bifurcation aneurysm, with good recovery. Digital subtraction angiography performed at this time showed the presence of left internal carotid artery aneurysms, 1 at the anterior wall of the paraclinoidal segment and 1 at the lateral wall of the intracavernous segment. In February 2008, the patient was referred from outside Finland to our department for microsurgical treatment of both aneurysms. A lateral supraorbital approach was used, and during extradural removal of the anterior clinoid with a rongeur, the ICCA ruptured. The base of the intracavernous aneurysm was involved in the rupture, and we used a single-clamp applicator to repair the internal carotid artery. Intraoperative digital subtraction angiography, indocyanine green video angiography, and Doppler ultrasonography showed a good flow in the artery. The paraclinoid aneurysm was uneventfully clipped during the same intervention. Intraoperative rupture of ICCA was repaired quickly and effectively by using a single-clamp applicator. Our case and experimental data from other microsurgical vascular experiences suggest that the future of intracranial vessel repair/anastomoses will be using microclips and other simpler devices more, allowing the neurosurgeon to perform fast and effective vessel repair.

LATERAL SUPRAORBITAL APPROACH APPLIED TO OLFACTORY GROOVE MENINGIOMAS

The lateral supraorbital approach for safely and completely removing olfactory groove meningiomas was assessed. Between September 1997 and June 2008, a total of 656 meningiomas were operated on by the senior author (JH) at the Department of Neurosurgery, Helsinki University Central Hospital; 66 were olfactory meningiomas. We retrospectively analyze the clinical data, radiological findings, surgical treatment, histology, and outcome of all the olfactory groove meningioma patients and discuss the operative techniques used. Sixty-six patients were operated on by the lateral supraorbital approach. The median preoperative Karnofsky Performance Scale score was 80 (range, 40-100). Three patients were redo cases in which the primary operation had been performed elsewhere. Seemingly complete tumor removal was achieved in 60 patients (91%); there was no surgical mortality. Postoperatively, 6 patients (9%) had cerebrospinal fluid leakage, 5 (8%) had new visual deficits, 4 (6%) had wound infections, 4 (6%) had cotton granulomas, and 1 (2%) had a postoperative hematoma. The median Karnofsky score at discharge was 80 (range, 40-100). Six patients had recurrent tumors; 3 underwent reoperations after an average of 21 months (range, 1-41 months); 1 was treated with radiosurgery, and 2 were only followed. During the median follow-up time of 45 months (range, 2-128 months), there were 4 recurrences (6%) diagnosed on average 32 months (range, 17-59 months) after surgery. The lateral supraorbital approach can be used safely for olfactory groove meningiomas of all sizes with no mortality and relatively low morbidity. Surgical results and tumor recurrence with this fast and simple approach are similar to those obtained with more extensive, complex, and time-consuming approaches.