Experiences with hemangiopericytoma in cranial base surgery

BACKGROUND: Haemangiopericytomas are rare vascular neoplasms which show either slow local tumour growth or aggressive progression in size with a high tendency of recurrence and metastasis. Manifestations of haemangiopericytomas in the area of the nose and sinuses are supposed to have a relatively benign course. To date clinical and histological parameters for prognosis are uncertain. Therefore in a quite large number of cases only the clinical course allows to evaluate the dignity of a haemangiopericytoma. PATIENTS AND RESULTS: We present our experience with five haemanglopericytomas in contact with the skull base out of a total number of 457 skull base tumours. The site of origin of these five haemangiopericytomas were: nasal septum, pterygopalatine fossa, oronasopharynx, temporal bone, and parotid gland. All neoplasms showed primary or recurrent tumor in contact with the skull base and an intracranial extension was observed twice. One patient died postoperatively of a cerebral infarction. Three patients showed one or more recurrences which were treated surgically. In one case 5 recurrences occurred. Despite of 4 surgical procedures within a period of 15 months, the tumour could be controlled only for a short period of time, and the patient died 16 months after the first operation. CONCLUSION: One has to consider that haemangiopericytomas of the head and neck show a potential malignant course. The vascular tumor may recur decades later. Adequate therapy and life-long follow-up are therefore mandatory in haemangiopericytomas. Complete surgical resection of the tumour is usually the treatment of choice, in spite of the high degree of surgical skill required, especially in advanced tumour and in case of recurrence.     

Craniofacial computer-assisted surgical planning and simulation

Computer-assisted planning and simulation of craniofacial surgery has progressed from development, through validation, and into clinical use. CT scans are transferred from the radiology department to a graphics workstation in the surgeon's office or laboratory, where data postprocessing and visualization for anatomic evaluation and surgical simulation are performed. Quantitative and qualitative comparative analyses between the plan/simulation and the actual postoperative result provide the feedback that validates or refutes the preoperative assessment and simulated intervention. The optimum surgical solution can be chosen from many possibilities. Interactive computer-assisted surgical simulation is also useful for morbidity-free training of inexperienced surgeons.     

Complications of craniofacial surgery for tumors involving the anterior cranial base

OBJECTIVE: To evaluate the risk factors for postoperative complications among patients undergoing craniofacial resection for the treatment of anterior cranial base tumors, a retrospective analysis of patients treated in University of Tokyo Hospital between September 1987 and November 1996 was conducted. METHODS: Twenty-nine patients underwent 33 craniofacial resections for tumors involving the anterior cranial base. Twenty-three of the 29 patients had malignant tumors and 6 patients had benign tumors. Anterior craniofacial resection was performed using a combination of intracranial and extracranial approaches. Radiotherapy and neoadjuvant chemotherapy were administrated to some patients. RESULTS: Severe intracranial infections were more common among patients who underwent partial frontal lobectomies (P < 0.03). These infections occurred only in patients who had been treated previously with a craniotomy (P < 0.02) and a total radiation dose of > or =60 Gy (P = 0.06). Neither management of the extracranial structures nor methods of reconstruction of the cranial base showed significant correlation with major postoperative complications. CONCLUSION: Compared with previous reports, craniofacial resection has become a relatively safe and effective procedure for the treatment of tumors involving the anterior cranial base. However, additional care should be taken with patients who have experienced a previous craniotomy, frontal lobe involvement, or radiotherapy with a total dose of > or =60 Gy.     

Giant cranial base tumours

Thirty-three patients with giant (diameter > or = 4.5 cm) cranial base tumours who underwent surgery at the Hadassah Hospital over the last ten years are described. Twenty-three of the patients had meningiomas, 4 neurinomas, one giant cell tumour, one haemangiopericytoma, and 4 had malignant meningiomas. Four tumours were at the cerebellopontine angle, 9 within the anterior cranial fossa, 8 petroclival, 8 on middle fossa floor, and 4 along the sphenoid ridge. The average pre-operative symptom duration was 31 months, range 3-180 months. Nineteen patients had a radical tumour resection, 10 subtotal, and 4 a partial resection on an average 1.7 operations per patient. The mean follow-up period from the first operation was 39 months (range 2-120). There was no mortality peri-operatively or during the follow-up period. The mean pre-operative Karnofsky score was 68 and at the last follow-up 76. There was no correlation between histology and degree of resection, complications, or status at last follow-up. The best resections (92% radical) and outcome (mean Karnofsky 92) with the least number of operations (mean 1.4) were in the anterior fossa and along the sphenoid wing. The patients requiring the most operations (mean 2.1), having the smallest percentage of radical resections (25%) and the least favourable outcomes (mean Karnofsky 52) were those with petroclival tumours. Patients with giant cranial base tumours have a good overall long-term prognosis, but especially those with petroclival tumours challenge us to improve our techniques.     

Protective coating of cranial nerves with fibrin glue (Tissucol) during cranial base surgery: technical note

OBJECTIVE: Cranial nerve deficit, either transient or permanent, is a common postoperative complication after cranial base surgery. Frequently, this occurs because intracranial nerves are directly involved in the cranial base lesion. However, any cranial nerve adjacent to the lesion can be damaged because of direct or indirect manipulation during surgery, leading to severe morbidity. We describe a new technique in which the adjacent intracranial nerves are protected from surgical trauma by coating the nerves with a biological two-component fibrin glue (Tissucol; Immuno A.G., Vienna, Austria). SURGICAL TECHNIQUE: The technique was performed in patients who underwent cranial base surgery for different types of lesions. After exposure of the operating field, the cranial nerves that were at risk of operative trauma were coated with a thin layer of fibrin glue using a double lumen catheter within a traditional suction device. RESULTS: With the application of fibrin glue, a protective layer of a rubbery consistency is formed around the nerve. No intraoperative complications or adverse effects of the application were noted. Moreover, no surgical injury of the nerves occurred and no or minimal postoperative cranial nerve deficit was noted in the coated nerves. CONCLUSION: Although it is difficult to compare the postoperative cranial nerve deficit in the coated nerves with a control group, we think that this technique is a valuable method to minimize or avoid intraoperative cranial nerve injury during cranial base surgery.     

Effects of annular cranial vault modification on the cranial base and face

Artificial modification of the cranial vault was practiced by a number of prehistoric and protohistoric populations, frequently during an infant's first year of life. We test the hypothesis that, in addition to its direct effects on the cranial vault, annular cranial vault modification has a significant indirect effect on cranial base and facial morphology. Two skeletal series from the Pacific Northwest Coast, which include both nonmodified and modified crania, were used: the Kwakiutl (62 nonmodified, 45 modified) and Nootka (28 nonmodified, 20 modified). Three-dimensional coordinates of 53 landmarks were obtained using a diagraph, and 36 landmarks were used to define nine finite elements in the cranial vault, cranial base, and face. Finite element scaling was used to compare average nonmodified and average modified crania, and the significance of the results were evaluated using a bootstrap test. Annular modification of the cranial vault produces significant effects on the morphology of the cranial base and face. Annular modification in the Kwakiutl resulted in restrictions of the cranial vault in the medial-lateral and superior-inferior dimensions and an increase in anterior-posterior growth. Similar dimensional changes are observed in the cranial base. The Kwakiutl face is increased anterior-posteriorly and reduced anterior-laterally to posterior-medially. Similar effects of modification are observed in the Nootka cranial vault and cranial base, though not in the face. These results demonstrate the developmental interdependence of the cranial vault, cranial base, and face.     

Reconstruction of upper cranial and cranial base defects utilizing the scalping flap

Reconstruction of midfacial defects by means of a scalping flap has been widely practiced and described in the literature. The advantages of the flap are familiar to surgeons who perform extirpations and reconstruction of the head and neck and include contiguous availability, simplicity of application, and a robust and redundant blood supply. Despite these merits, the flap has not been widely used for reconstructions of large anterior cranial defects or defects of the cranial base. A retrospective review of 11 patients who underwent reconstructions between 1990 and 1995 was performed. In each case, a reconstruction of a large anterior cranial or cranial base defect was carried out. The resulting soft-tissue defect was restored via the scalping flap. In six cases, this was carried out in a single procedure. In five cases, flap division and insetting were carried out in a subsequent procedure, following a 1- to 2-week delay. In all cases, the extirpation and reconstruction were well tolerated, and the average time of hospitalization was 5.9 days and ranged from 3 to 11 days. No major surgical complications occurred. One of 11 patients had a minor complication not requiring surgical intervention. There was one recurrence of a cranial base tumor approximately 2 years following the initial resection and reconstruction. In all cases, the final aesthetic and functional results were acceptable to excellent. Follow-up ranged from 11 months to 5 years. In conclusion, the scalping flap can be effectively utilized for soft-tissue coverage in the reconstruction of anterior cranial and cranial base defects. Use of this simple and versatile flap in craniofacial reconstruction is well tolerated and is associated with a low morbidity, a good aesthetic result, and a short hospital stay.     

Flap selection in cranial base reconstruction

We have compared our local, pedicled, and free-flap reconstructions for 90 skull base defects performed over the past 10 years. The pericranial flap was found to provide a reliable dural seal. Free-flap reconstructions exhibited a significantly higher incidence of uncomplicated primary wound healing (95 versus 62.5 percent) and a much lower incidence of flap loss (0 percent), cerebrospinal fluid leak (5 percent), meningitis, and abscess (0 percent) when compared with defects reconstructed with pedicled myocutaneous flaps. We conclude that microvascular free-tissue transfer is the safest, most economical procedure when faced with moderate to large composite defects of the cranial base.     

Three-dimensional computed tomographic reconstruction: planning tool for surgery of skull base pathologies

Maintenance of homeostasis in the upper small bowel is a vital process for the body and therefore highly controlled. The enteric nervous system and the endocrine system are the regulators in this process influencing each other. The endocrine system in the gut consists of the classical hormones [cholecystokinin (CCK) secretin] to evoke motility or secretion. They are under control of releasing factors which are probably influenced by the enteric nervous system. Diazepam binding inhibitor and luminal CCK-releasing factor are likely candidates for CCK-releasing peptides in the negative feedback process in the absence of pancreatic juice. Experimental evidence suggests a secretin-releasing peptide. Further studies will be needed to determine the physiological role of each of these peptides. Monitor peptide in the pancreatic juice seems to function as a specific positive enhancement for CCK release. All these peptides are inactivated by the proteolytic enzymes during the interdigestive period. The discovery of additional releasing peptides and factors is very likely.     

Large arachnoid cysts at the cranial base

Two infants who presented with macrocephaly had very large noncommunicating cysts at the cranial base that were displacing the brain. Only one of the patients was hydrocephalic; he eventually underwent ventriculoperitoneal shunting after craniotomy and attempted internal drainage of the cyst. The other infant had a cystoperitoneal shunt. Both have done well after 4 and 6 years of follow-up, respectively. These large arachnoid cysts are bilateral lesions with the potential for severe surgical complications and a questionable possibility of cure. The authors recommend systematic radiological investigation to decide the appropriate therapy, including an analysis of the patency of the subarachnoid pathways with radionuclide cisternography and cystography. Simple cystoperitoneal shunting may be the appropriate therapy for most of these large lesions. (Neurosurgery, 6: 76--81, 1980).     

Anesthesiological support, postoperative care and the results of the surgical treatment of patients with tumors of the base of the posterior cranial fossa

Problems of anesthesiological maintenance, measures of the postoperative management and results of surgical treatment of 76 patients with an oncological process on the base of the posterior cranial fossa are discussed. An analysis of informative-regulatory and adaptational reactions of organism is made on the basis of the intervalogram in the course of operative interventions near by the cerebral trunk. The results are estimated.     

Transnasal endoscopic excision of midline nasal dermoid from the anterior cranial base

We recommend that every patient with a midline nasal dermoid be evaluated preoperatively by fine-cut CT scan, in the axial and coronal planes, using both bone and soft-tissue algorithms. Because of CT limitations for assessing soft tissue at the cranial base, a complementary thin-section, high-resolution, multiplanar MRI scan should be considered. Transnasal endoscopic excision of midline nasal dermoid should be used if the dermoid is located within the nasal cavity, and there is minimal or no cutaneous involvement. This approach can be combined with a short vertical midline lenticular excision of a cutaneous punctum. Vertical cutaneous excision should be limited; the best location is the nasal tip. Vertical nasal scars over the bony pyramid invariably widen no matter what intradermal suture is used. Endoscopic removal should be considered even if preoperative radiologic studies show extension to the anterior cranial fossa. Endoscopic excision could also be used to resect a dermoid extending between the dural leaves of anterior fossa. However, a combined intra-extracranial approach is necessary if the dermoid is in the falx cerebri. We agree with other authors that frozen sectioning the superior margin of the specimen should be done to ensure that there is no intracranial extension. Valsalva maneuver during endoscopic visualization of the cranial base is a valuable means of ruling out a cerebral spinal fluid leak.     

Complications and sequelae of nasal base and tip surgery

A considerable body of recent evidence shows that preattentive processes can carve visual input into candidate objects. Borrowing and modifying terminology from Kahneman & Treisman (1984), this paper investigates the properties of these preattentive object files. Experiments 1-3 show that preattentive object files are loose collections of basic features. Thus, we can know preattentively that an object has the attributes "red" and "vertical" and yet have no idea if any part of the object is red and vertical. Experiment 4 shows that some information about the structure of an object is available preattentively, but Experiments 5-12 search for and fail to find any preattentive representation of overall shape. Appreciation of the overall shape of an object appears to require the binding together of local form features--a process that requires attention.