Complications of anterior skull base surgery

The complications associated with anterior skull base surgery were reviewed in 49 consecutive patients treated between November 1986 and August 1993. All procedures involved a combined otolaryngologic and neurosurgical approach, and the senior otolaryngologist was the same. Fifty-two procedures were completed; 37 for malignant disease and 15 for benign disease. Twenty-one of the 52 procedures had postoperative complications, a 40% complication rate. One postoperative death occurred from a myocardial infarction, for a 2% mortality rate. Infections complications were the most common, occurring in 19% of cases. The one case of meningitis responded to antibiotic therapy, without neurologic sequelae. Seven cerebrospinal fluid leaks occurred (13%); five resolved with conservative management, and two required reoperation. There was no significant difference between complication rates for patients with previous craniotomy, radiation therapy, or chemotherany compared with those with no prior therapy (p > .05). More complications occurred in patients with malignant disease than in those with benign disease (46% vs 27%), but this was not statistically significant (p > .05). Anterior and anterolateral skull base resection as part of a multidisciplinary approach to diseases of this region may provide improved palliation and may offer possible improved survival with acceptable surgical mortality. Although only 6% of patients were left with permanent neurologic sequelse in this series, the risks of serious complications are considerable.     

Endoscopic endonasal skull base surgery: Part 1--The midline anterior fossa skull base.

OBJECTIVE: An endonasal endoscopic surgery to the anterior fossa skull base was developed in cadaver dissection as a minimally invasive surgical technique and, subsequently, used in patient treatment. METHODS: Six cadaver head specimens were used. Ideal head positioning and various surgical routes were studied. To estimate the extent of surgical exposure provided by this technique, the width of the exposed anterior cranial fossa was measured between the medial margin of the orbits, the optic nerves and the carotid arteries. Three demonstrative patient cases are presented. RESULTS: Ideal head positioning was discovered to be at 15-degree extension of the forehead-chin line. Paraseptal, middle meatal and middle turbinectomy approaches were developed. The average width between the medial orbits was measured to be 24 mm (range 22-29 mm) at the crista galli level, 27 mm (range 24-30 mm) at the planum sphenoidale, 18 mm (range 15-22 mm) between the optic nerves, and 17 mm (range 13-21 mm) between the rostral carotid siphons. This technique, when it was applied in patient care, proved to be minimally invasive. CONCLUSIONS: This endoscopic endonasal approach provided a direct "short-cut" access to the midline anterior fossa skull base. This technique can be used for the surgical treatment of cerebrospinal fluid (CSF) leak, meningiomas, craniopharyngiomas, pituitary adenomas, and other midline intracranial anterior skull base lesions. This is the first report in the English literature describing endonasal endoscopy for the surgical treatment of primary intracranial anterior fossa skull base lesions.     

Advances in endoscopic sinonasal and anterior skull base surgery

Endoscopic transnasal surgery is rapidly replacing more radical external 'open' procedures. At Groote Schuur Hospital, Cape Town, we performed 94 advanced endoscopic sinonasal and anterior skull base procedures over a 2-year period. Most of these would previously have been performed using large external incisions requiring more invasive surgery with significantly higher morbidity. Endoscopic surgery is more cost-effective than open procedures because it reduces duration of hospitalisation, operating time and theatre consumables and obviates the need for postoperative intensive care unit admission.We have had no complications other than 2 cerebrospinal fluid leaks, but the potential risks of endoscopic sinonasal and skull base surgery are significant and proper training is required.     

Transbasal approach to skull base tumors: evaluation and proposal of classification

A clinical study of the TBA was performed in 22 patients harboring tumors of the skull base. The follow-up ranged from 3 to 89 months (average, 30.5 months). The main complications were intracerebral hematoma, ptosis, and infection. One patient died (4.5%) because of an extradural hematoma. Eight patients died during the follow-up because of tumor complications. Among the survivals, the median of the Karnofsky index was 96.4. Based on this study, we propose a classification for the TBA, according to its extension.     

Endoscopic anterior skull base surgery: intraoperative considerations of the crista galli

We sought to measure the anatomic dimensions of the crista galli in a consecutive series of patients undergoing the endoscopic transcribriform approach for anterior skull base tumors at a tertiary academic university hospital. We performed a retrospective chart review of patients undergoing purely endoscopic transcribriform surgery for sinonasal and skull base lesions. Main outcome measures included radiological dimensions of the crista galli. A total of 12 patients were identified and treated by the senior authors at the University of Pennsylvania. The average crista galli dimensions were 12.7 ± 2.4 mm (anterior-posterior) and 12.9 ± 2.5 mm (cranial-caudal dimension). Knowledge of the dimensions of the crista galli is important in preoperative planning for both instrumentation and access.     

Nasal reconstruction in surgery of the anterior skull base.

OBJECTIVES: We sought to evaluate the effectiveness of a number of surgical maneuvers in nasal reconstruction of a diverse population of patients undergoing skull base surgery.Study design We conducted a retrospective review of a cohort of patients undergoing nasal reconstruction during surgery of the anterior skull base and craniovertebral junction. METHODS: All patients undergoing skull base surgery and nasal reconstruction by the senior author (Y.D.) with a minimum follow-up of 12 months from 1997 to 2001 were evaluated. Preoperative and postoperative photographs and clinical evaluation were examined in detail with particular attention focused on the nasal complex. RESULTS: A total of 47 patients were evaluated for this study, including those who had undergone anterior craniofacial resections (n = 14), Le Fort osteotomies (n = 5), subcranial approaches (n = 10), maxillotomies (n = 8), and midfacial disassemblies (n = 10). Primary calvarial bone graft reconstruction of the anterior craniofacial group was facilitated with the use of positioning plates and resuspension of the upper lateral cartilages when available. In contradistinction to secondary bone grafting, dorsal grafts in this group extended to the native nasal bone length. A small overlay bone graft was thought to be necessary when the nasal root was osteotomized in conjunction with the orbital and/or maxillary segments to maintain dorsal height in the long term. Le Fort osteotomy patients require refixation of the septum to the anterior nasal spine region for stability. CONCLUSIONS: Use of the techniques outlined in this article appears to be associated with gratifying long-term nasal form in reconstruction of the anterior skull base.     

MRI vs. high-resolution CT scanning: evaluation of the anterior skull base

While magnetic resonance imaging (MRI) is no longer a tool of the future, its availability is limited. Most hospitals still use high-resolution computed tomography (CT) scanning as their major imaging modality. Although numerous articles point to the improved diagnostic uses of MRI--as compared to high-resolution CT--a change from high-resolution CT scanning to MRI scanning throughout the United States would cost billions of dollars. We should, therefore, delineate those clinical situations in which magnetic resonance imaging is distinctly superior to high-resolution CT scanning. It is already an accepted fact that MRI provides improved imaging of the central nervous system, but, while recent articles maintain the superiority of MRI head and neck imaging, the advantages to the clinician are less clear. We present representative cases of large malignant tumors of the frontal, ethmoid, and sphenoid sinuses, in which the full extent of the disease which involved intracranial structures and the orbit was better defined on the MRI scan than it was on the high-resolution CT scan. Decisions concerning the involvement of the infratemporal fossa, the cavernous sinus, the optic chiasm, the pituitary, and the frontal lobes were more easily made when based upon magnetic resonance imaging, while the tumor involvement as evaluated by CT scanning was much less clear. Establishment of the problem regions of the head and neck--when magnetic resonance imaging is superior to high-resolution CT scanning--will assist in identification of the true need for this tool in the practice of the otolaryngologist--head and neck surgeon.     

Ophthalmological outcome after orbital entry during anterior and anterolateral skull base surgery

OBJECT: Partial resection of the orbital bones is not uncommon during the excision of anterior and anterolateral skull base tumors. Controversy exists regarding the need for and extent of reconstruction after this procedure. The authors studied this factor in a series of patients. METHODS: The authors conducted a retrospective review of 56 patients in whom resection of 57 anterior or anterolateral skull base tumors and partial excision of the orbital bone were performed. Adverse ophthalmological outcomes were noted in 16 patients, in nine of whom adverse outcomes were believed to be directly related to resection of the orbital walls. Some degree of orbital reconstruction was performed during 23 of the 57 procedures. An adverse orbital outcome was strongly associated with resection of the orbital floor and resection of two thirds or more of two or more orbital walls, but not with the presence or absence of orbital reconstruction. The later finding, however, is likely a function of selection bias. CONCLUSIONS: In most patients elaborate orbital reconstruction is not necessary after partial excision of the orbital bones. Isolated medial and lateral orbital wall defects, or combined superior and lateral orbital wall defects, especially in cases in which the periorbita is intact, probably do not require primary reconstruction. In cases of orbital floor defects, whether isolated or part of a multiple-wall resection, primary reconstruction is recommended.     

Titanium in reconstructive surgery of the skull and face

Titanium is widely used as an implant material. This report describes its use for cranioplasty and malar defects and the technique used to fashion these prostheses in a centre which does not have the facility for producing computer-generated full-size craniofacial models. The use of these prostheses has produced very satisfactory results with minimal morbidity and no complications.     

Extended pericranial flap and bone graft reconstruction in anterior skull base surgery.

OBJECTIVES: The objectives of this study was to establish a rationale for repairing large anterior skull base defects with an extended pericranial flap and split calvarial bone graft; to define large anterior skull base defects as those spanning the anterior cranial measuring at least 3.0 x 4.0 cm; and to describe the surgical technique and compare it with alternative strategies.Study design Thirty-four patients underwent anterior craniofacial resection of anterior skull-based tumors of varying histology with reconstruction using an extended pericranial flap and split calvarial bone graft. RESULTS: The survival of the pericranial flap and bone graft was maintained in 33 of 34 patients. There was 1 episode of postoperative cerebrospinal fluid leak, 1 episode of osteomyelitis of the bone graft and an epidural abscess, and 1 episode of asymptomatic pneumocephalus. CONCLUSION: Split calvarial bone graft with an extended pericranial flap is an effective technique for reconstructing large anterior skull base defects.     

Avoidance of postoperative epistaxis and anosmia in endonasal endoscopic skull base surgery: a technical note

Background

Most endoscopic transsphenoidal approaches jeopardize the sphenopalatine artery and septal olfactory strip (SOS), increasing the risk of postoperative anosmia and epistaxis while precluding the ability to raise pedicled nasoseptal flaps (NSF). We describe a bilateral “rescue flap” technique that preserves the mucosa containing the nasal-septal vascular pedicles and the SOS. This approach can reduce the risk of postoperative complications, including epistaxis and anosmia.

Methods

A retrospective analysis was conducted of all patients who underwent endoscopic transsphenoidal surgery with preservation of both sphenopalatine vascular pedicles and SOS. In a recent subset of patients, olfactory assessment was performed.

Results

Of 174 consecutive operations performed in 161 patients, bilateral preservation of the sphenopalatine vascular pedicle and SOS was achieved in 139 (80 %) operations, including 31 (22 %) with prior transsphenoidal surgery. Of the remaining 35 operations, 18 had a planned formal NSF and 17 had prior surgery or extensive lesions precluding use of this technique. Of pituitary adenomas, RCCs or sellar arachnoid cysts, 118 (94 %) underwent this approach, including 91 % of patients who had prior surgery. Preoperative olfaction function was maintained in 97 % of patients that were tested. None of the patients had postoperative arterial epistaxis.

Conclusion

Preservation of bilateral sphenopalatine vascular pedicles and the SOS is feasible in over 90 % of patients undergoing endonasal endoscopic surgery for pituitary adenomas and RCCs. This approach, while not hindering exposure or limiting instrument maneuverability, preserves the nasoseptal vasculature for future NSF use if needed and appears to minimize the risks of postoperative arterial epistaxis and anosmia.     

Risk of incisional recurrence after midface and anterior skull base surgery in sinonasal malignancies

We sought to determine the risk of tumor incisional recurrence in patients receiving surgery and postoperative radiation therapy for locally advanced sinonasal malignancies. Medical records for 70 patients newly diagnosed with nonmetastatic American Joint Committee on Cancer stage II to stage IV sinonasal malignancies between 1991 and 2003 were retrospectively reviewed. Patient demographics and tumor variables were recorded. All patients underwent upfront surgical resection with postoperative three-dimensional conformal proton beam radiotherapy. Recurrence and survival-related outcomes were recorded. Two patients with squamous cell carcinoma had pathologically confirmed tumor recurrence at the incision site. The actuarial risk of incisional recurrence for the entire group at 1 year was 3%. One of the two patients had a maxillary sinus tumor and developed isolated skin recurrence along the transfacial incision. The other patient with an ethmoid sinus tumor developed isolated dural recurrence along the craniotomy incision. Both patients underwent multiple courses of salvage surgery and radiation therapy. One was successfully salvaged locally but developed distant metastases and the other died of local recurrence. Tumor seeding following transfacial and craniotomy surgery can occur, especially for squamous cell carcinoma. Sound oncological surgical technique, even when utilizing these difficult surgical approaches, is important to minimize incisional recurrence.     

Safety of drilling for clinoidectomy and optic canal unroofing in anterior skull base surgery

Background

Skull base drilling is a necessary and important element of skull base surgery; however, drilling around vulnerable neurovascular structures has certain risks. We aimed to assess the frequency of complications related to drilling the anterior skull base in the area of the optic nerve (ON) and internal carotid artery (ICA), in a large series of patients.

Methods

We included anterior skull base surgeries performed from 2000 to 2012 that demanded unroofing of the optic canal, with extra- or intradural clinoidectomy and/or drilling of the clinoidal process and lateral aspect of the tuberculum sella. Data was retrieved from a prospective database and supplementary retrospective file review. Our IRB waived the requirement for informed consent. The nature and location of pathology, clinical presentation, surgical techniques, surgical morbidity and mortality, pre- and postoperative vision, and neurological outcomes were reviewed.

Results

There were 205 surgeries, including 22 procedures with bilateral optic canal unroofing (227 optic canals unroofed). There was no mortality, drilling-related vascular damage, or brain trauma. Complications possibly related to drilling included CSF leak (6 patients, 2.9 %), new ipsilateral blindness (3 patients, 1.5 %), visual deterioration (3 patients, 1.5 %), and transient oculomotor palsy (5 patients, 2.4 %). In all patients with new neuropathies, the optic and oculomotor nerves were manipulated during tumor removal; thus, new deficits could have resulted from drilling, or tumor dissection, or both.

Conclusion

Drilling of the clinoid process and tuberculum sella, and optic canal unroofing are important surgical techniques, which may be performed relatively safely by a skilled neurosurgeon.     

Free tissue transfer and local flap complications in anterior and anterolateral skull base surgery

BACKGROUND: Advances in reconstructive techniques over the past two decades have allowed the resection of more extensive skull base tumors than had previously been possible. Despite this progress, complications related to these cases remain a concern. METHODS: Univariate and multivariate analyses were used to determine the relationship of host, tumor, defect, treatment, and reconstructive variables to wound and systemic complications after anterior and anterolateral skull base resections. The study included 67 patients receiving local flap (LF) or free tissue transfer (FTT) reconstructions during an 8-year period. RESULTS: Overall, 28% of patients had a major wound complication, and 19% had a major systemic complication. LF and FTT flaps had similar rates of wound complications. LF reconstructions were associated with late wound breakdown problems, and FTT flap complications were primarily acute surgery-related problems. CONCLUSIONS: The surgical reconstruction of skull base defects should be planned on the basis of the ability of the technique to attain safe closure and maintain integrity after radiation therapy.     

Prevention of postoperative facial edema with steroids after facial surgery

A one-bolus (dose) of 1 g of methylprednisolone was administered intravenously to patients undergoing facial surgery or craniofacial surgery, before the termination of the operative procedure. The degree of facial edema noted was reduced, and when it occurred, it was mild and of shorter duration. These observations were made on the experimental design first, and later in the clinical setting. No adverse effects were noted, and patients given this treatment required less pain medication in the immediate postoperative period. The mechanism of action of the steroids is multifactorial, related to decrease in the accumulation of fluid at the capillary level, and reduction of flow at the venoarterial sphincters. The use of steroids is safe when used with caution in selected patients, and by experienced surgeons.Based on presentation at the seventeenth annual meeting of the American Society for Aesthetic Plastic Surgery, Washington, D.C., March, 1984