Fibrous dysplasia involving the skull base and temporal bone

OBJECTIVE

To gain a broader appreciation of the clinical presentation, operative treatment, and outcome of patients with fibrous dysplasia involving the skull base.

DESIGN

Retrospective review of a clinical case series.

SETTING

A single tertiary academic medical center.

PATIENTS

Twenty-one patients with histopathologically confirmed fibrous dysplasia involving the skull base cared for over a 15-year-period (1983-1998).

MAIN OUTCOME MEASURES

Clinical and radiographic location of the fibrous dysplasia lesions within the skull base, clinical presentation, surgical intervention, and clinical outcome were tabulated for each patient.

RESULTS

The ethmoids were most commonly involved (71%), followed by the sphenoid (43%), frontal (33%), maxilla (29%), temporal (24%), parietal (14%), and occipital (5%) bones. The most common presenting features included atypical facial pain and headache, complaints referable to the sinuses, proptosis and diplopia, hearing loss, and facial numbness. Surgical treatment, guided by clinical presentation, ranged from simple biopsy with conservative follow-up to craniofacial resection.

CONCLUSIONS

Fibrous dysplasia can present in myriad ways within the skull base. Modern imaging modalities and histopathologic analysis have made diagnosis relatively straightforward. Surgery, particularly in such a challenging region as the skull base, should be reserved for patients with functional impairment or a cosmetic deformity. Because of the benign nature of the condition, the surgery itself should be relatively conservative, with the primary goal being preservation of existing function.

Endoscopic transsphenoidal surgery

BACKGROUND

Endoscopic transsphenoidal surgery was developed under a minimally invasive surgical strategy. This endonasal transsphenoidal endoscopy eliminates a sublabial or transfixional incision, the use of a transsphenoidal retractor and any nasal packing.

MATERIALS AND METHOD

Reported are 160 patients who had undergone endoscopic transsphenoidal surgery from 1993 to 1999. Seventy were men and ninety women. Age ranged from 14 to 88 years (median 43 years). Among the 160 patients, 128 had pituitary adenomas, 9 had anterior fossa meningiomas, 7 had clival chordomas and 16 patients had other pathologies.

RESULTS

Among the 68 patients with hormone-none-secreting adenomas, 53 (78%) patients had gross total removal. Among the 35 patients with prolactinomas, 24 (71%) patients exhibited normalized prolactin levels postoperatively. Eleven (70%) patients among the 16 with Cushing's disease had normal postoperative cortisol levels. Among the 9 patients with acromegaly, 7 (78%) had normalized postoperative IGF-1 levels. Among the 9 patients with anterior cranial fossa meningiomas. 7 had gross total removal and 2 had subtotal removal. Among the 7 patients with clival chordomas, 5 had total removal and 2 had subtotal removal. One patient with a large calcified recurrent pituitary fibrosarcoma died postoperatively. Postoperative morbidities included cerebrospinal fluid (CSF) leak in 6%, meningitis in 1.2%, deterioration of anterior pituitary function in 11%, temporary diabetes insipidus in 4%, permanent diabetes insipidus in 3%, and sinusitis in 1.2%. Outpatient surgery was performed in 2 patients. One hundred and eleven patients (66%) stayed in the hospital only overnight. Postoperative discomfort was minimal.

CONCLUSION

Endoscopic endonasal transsphenoidal surgery in this series resulted with comparable surgical outcomes to conventional microscopic transsphenoidal surgery. Patients' quick recovery, short hospital stays, and minimal postoperative discomfort have been observed.

Transsphenoidal approaches for the extracapsular resection of midline suprasellar and anterior cranial base lesions

OBJECTIVE

The transsphenoidal approach is an effective method for treating tumors contained within the sella or extending into the suprasellar cistern. The technique of tumor dissection is predicated on preservation of the integrity of the diaphragma, i.e., intracapsular removal. Gross total extracapsular dissection may, however, be accomplished either by using a standard approach to the pituitary fossa or by extending the exposure to include removal of a portion of the planum sphenoidale and division of the superior intercavernous sinus.

METHODS

Included in this series were 14 patients with parasellar or sellar tumors with extension into the anterior fossa and/or suprasellar cistern. For 4 of 14 patients (29%), extracapsular access was gained by broaching the tumor capsule from within the pituitary fossa. For the remaining 10 of 14 patients (71%), the dura of the floor of the sella and the planum sphenoidale was exposed, using neuronavigation to verify the limits of bony dissection; extracapsular tumor resection was performed using the operating microscope and endoscopy as indicated. The dural defect was repaired with abdominal fat, the sellar floor and planum sphenoidale were reconstructed, and in selected cases a lumbar drain was placed.

RESULTS

Seven of 14 tumors (50%) were craniopharyngiomas, 3 of 14 (21%) were pituitary adenomas, and 2 of 14 (14%) were meningiomas. There was one case of lymphocytic hypophysitis and one yolk sac tumor. Gross total resection was possible in 11 of 14 cases (79%). Immediate postoperative visual function worsened in 2 of 14 cases (14%), improved in 3 of 14 cases (21%), and was stable in the remainder of cases. Postoperatively, 2 of 14 patients (14%) developed bacterial meningitis. Overt postoperative cerebrospinal fluid rhinorrhea was not observed.

CONCLUSION

Gross total extracapsular resection of midline suprasellar tumors via a transsphenoidal approach is possible but is associated with a higher risk of complications than is standard transsphenoidal surgery.

Histochemical studies of the masseter, the temporal and small zygomaticomandibular, and the temporomandibular masticatory muscles from aged male and female humans. Fiber types and myosin isoforms

The purpose of this study was to investigate the histology of two small masticatory muscles from females and males of more than 70 years of age. By using immuno- and enzyme histochemistry the muscles were characterized by their fiber types and myosin heavy chain pattern. The observations were compared with similar studies of the masseter and temporalis muscles. Previously the two small muscles have been described based solely upon their gross anatomy. One muscle originates from the anterior, deep surface of the temporal fascia and inserts in the temporal tendon: the temporo-mandibular muscle (TM). The other muscle originates from the upper part of the temporal surface of the frontal process of the zygomatic bone and the adjacent part of the frontal bone and inserts in the temporal tendon: the zygomaticomandibular muscle (ZM). In the masseter, TM, and ZM, most of the autopsy samples contained an abundant number of fibers containing neonatal myosin heavy chains while in the temporal muscle specimens, such fibers were sparse and scattered. Electrophoresis followed by immuno-staining of Western blots supported the histochemical findings. There was no obvious correspondence between fiber typing based upon ATPase activity and the neonatal myosin heavy chain content in the muscle fibers. Neither did the fibers show accordance in their content of adult slow and fast myosin heavy chains and in their content of neonatal myosin heavy chain.

Pleomorphic adenoma of the pterygopalatine fossa: a case report

Pleomorphic adenoma (PA) is the most common benign tumor of the major salivary glands. It can also Occur in the minor salivary glands, mainly in the oral cavity, and in other sites in the head and neck region. We present a very rare case of PA in the pterygopalatine fossa. Surgical resection of the tumor was performed via the transmaxillary approach. The patient has experienced neither surgical complications nor recurrence in the past 3 years. This case suggests that a localized benign tumor in the pterygopalatine fossa can be removed safely and efficaciously via a transmaxillary approach.

Using simulated neuronal cell models for detection of epileptic seizures in foramen ovale and scalp EEG

OBJECTIVE

To demonstrate a novel approach for real-time and automatic detection of epileptic seizures in EEG recorded with foramen ovale (Fov) or scalp electrodes.

METHODS

Our seizure detection method is based on simulated leaky integrate and fire units (LIFU), which are classical simple neuronal cell models. The LIFUs are connected to a signal preprocessing stage and increase their spiking rates in response to rhythmic and synchronous EEG signals as typically occur at the onset and during seizures.

RESULTS

We analyzed 22 short-term (10+/-3 min) and 4 long-term (18+/-7 h) Fov or scalp EEGs of 10 patients with drug resistant partial epilepsy. Seizures (n=36) were marked by increases of the LIFUs spiking rates above a preset threshold. The durations of increased spiking rates due to seizures were always longer than 10 s (36+/-21 s) and allowed separation from artifacts, which caused only short durations (1.2+/-0.6 s) of high spiking rates. The LIFUs correctly detected all the seizures and produced no false alarms. In the long term Fov EEGs seizure detection occurred before the onset of clinical signs (41+/-22 s).

CONCLUSIONS

By using simulated neuronal cell models it is possible to automatically detect epileptic seizures in scalp and Fov EEG with high sensitivity and specificity.

Endonasal endoscopic removal of growth-hormone-secreting pituitary adenomas

Trans-sphenoidal removal of pituitary tumours using the endonasal endoscopic technique, a novel application, is herein reported in five consecutive patients with growth-hormone-secreting pituitary adenomas seen at a teaching hospital in Hong Kong. All five patients demonstrated complete tumour removal on postoperative imaging and hormonal assessment following the procedure. Surgical morbidity and symptoms were minimal; postoperative obstructive nasal packing was not required with this technique, which greatly improved patient comfort. Preliminary experience suggests that the endonasal endoscopic approach is a safe and effective alternative to the conventional trans-septal microscopic method for the treatment of pituitary tumour. A randomised controlled trial comparing these two approaches is currently underway at this institution.

Surgical management of meningioma en plaque of the sphenoid ridge

BACKGROUND

Meningioma en plaque represents a morphological subgroup within the meningiomas defined by a carpet or sheet-like lesion that infiltrates the dura and sometimes invades the bone. Differential diagnosis includes fibrous dysplasia, osteoma, and osteoblastic metastasis. This study was conducted to obtain pathological information on patients with meningioma en plaque and to correlate with the surgical management.

METHODS

A retrospective review of all the adult operative cases at the University Hospital in a seven and a half-year period from July 1, 1990 to December 31, 1997 identified 150 patients who were operated on for intracranial meningiomas. The medical records were reviewed to identify cases of meningioma en plaque. Forty-seven patients had involvement of the sphenoid ridge and 6 of them fulfill the criteria for meningioma en plaque.

RESULTS

All 6 patients with meningiomas en plaque were female and had hyperostosis of the sphenoid bone. In 5 of them, the bone was sent for histopathological examination. Four of those had infiltration of the bone by meningioma cells. Proptosis was the most common presentation. Half of the patients presented with visual disturbances that improved after surgery. All patients were operated using a fronto-temporal approach with orbital decompression.

CONCLUSION

All the involved bone should be removed to prevent recurrence. In those cases with involvement of the cavernous sinus and/or the orbital apex, a subtotal but extensive removal combined with bony decompression of the cranial nerves at the superior orbital fissure and optic canal frequently produces good functional and cosmetic results.

Surgical management of clinoidal meningiomas

OBJECTIVE

Surgical outcome has been less than desirable in the management of patients with clinoidal meningiomas in the past, and little attention has been directed at improving their visual function. The purpose of this article is to advocate an available cranial base technique for removing these difficult tumors and to delineate the technique's advantages that aid in achieving an improved extent of tumor resection and enhancing the patients' overall outcome, particularly their visual outcome.

METHODS

A retrospective analysis was performed on 15 consecutive patients with clinoidal meningiomas (including a patient with hemangiopericytoma) who underwent surgical resection at the Cleveland Clinic Foundation between June 1995 and January 2000. A cranial base technique consisting of extradural anterior clinoidectomy, coupled with optic canal unroofing and optic sheath opening, was used in 13 patients, and standard pterional craniotomy was used in 2. Eight of 15 patients had significant visual deficits preoperatively. All patients had thorough preoperative and postoperative ophthalmological evaluations. The follow-up period ranged from 6 to 60 months (mean, 37.2 mo).

RESULTS

Total resection was achieved in 13 (86.7%) of the 15 patients in this series, and the majority of the patients with preoperative visual impairment experienced significant improvement (6 of 8 patients; 75%).

CONCLUSION

In the majority of patients with clinoidal meningiomas, total resection may be achieved with minimal complications. For large tumors encasing the optic nerve and internal carotid artery, or for those tumors causing preoperative visual impairment, use of the cranial base technique delineated in this study may lead to significant improvement in the patients' visual and overall outcomes.

Combined use of sphenoidal electrodes and the dipole localization method for the identification of the mesial temporal focus

We attempted to sub-classify four cases who show temporal spikes on standard scalp electroencephalogram (EEG), using sphenoidal electrodes and the dipole localization

METHOD

In a case with mesial temporal epilepsy, spikes showed phase reversal in a sphenoidal electrode, and the spike dipoles were estimated to be in the mesial temporal lobe. In a case with lateral temporal epilepsy, spikes showed no phase reversal in a sphenoidal electrode, and the spike dipoles were estimated to be in the lateral temporal lobe. In two cases out of four, spikes showed phase reversal in sphenoidal electrodes, whilst the dipoles were estimated to be in the frontal lobe. Clinical features also suggested a diagnosis of frontal lobe epilepsy. In one of the two cases in which frontal lobe epilepsy was suspected, ictal dipoles as well as interictal spike dipoles indicated participation of the frontal lobe in the genesis of seizures. Nevertheless, only mesial temporal lobectomy was performed based on results obtained by invasive subdural electrodes. As a result, seizures were not controlled. Although sphenoidal electrodes were useful for differentiating between mesial and lateral temporal lobe foci, it is advisable to use them in combination with the dipole localization method to identify frontal lobe foci.

[The Interesting Case No. 42. Differential diagnosis of epistaxis]

Epistaxis is a symptom and one of the most frequent medical emergencies. In most cases haemorrhages concern the anterior parts of the septum, in particular the Locus Kiesselbachi. Thus they are harmless and therapy is easy to handle. We report a case of a 55-year-old lady with relapsing epistaxis due to a pseudoaneurysm after surgery of a meningioma of the sphenoid bone. This type of epistaxis is rare and may culminate into a life-threatening event. The case demonstrates the importance of an exact differential diagnostic evaluation by use of modern imaging techniques for severe and life-threatening symptomatic nose-bleeding.

Transsphenoidal hypophysectomy for treatment of pituitary-dependent hyperadrenocorticism in 7 cats

OBJECTIVE

Evaluation of microsurgical transsphenoidal hypophysectomy for the treatment of pituitary-dependent hyperadrenocorticism (PDH) in cats.

STUDY DESIGN

Prospective clinical study.

ANIMALS OR SAMPLE POPULATION

Seven cats with PDH.

METHODS

Urinary cortisol/creatinine ratios, pituitary-adrenocortical function tests, and computed tomography (CT) were performed on 7 cats that presented with a provisional diagnosis of hyperadrenocorticism. All cats underwent microsurgical transsphenoidal hypophysectomy with histologic examination of the excised specimen. Follow-up consisted of clinical evaluation, repeat adrenocortical function testing, and CT.

RESULTS

Four cats had concurrent diabetes mellitus. In all cats, the urinary cortisol/creatinine (C/C) ratios were elevated. The dexamethasone screening test showed that 2 cats did not meet the criterion for hyperadrenocorticism. The response of the cats' plasma concentrations of cortisol and adrenocorticotrophic hormone to a high dose of dexamethasone varied from very sensitive to completely dexamethasone resistant. Basal plasma alpha-melanocyte-stimulating hormone concentrations were elevated in 2 cats with a pars intermedia adenoma and in 3 cats with an adenoma that originated from the anterior lobe. Preoperative CT enabled accurate assessment of pituitary size (5 nonenlarged pituitaries with a height <4 mm and 2 enlarged pituitaries with a height >5 mm) and localization relative to intraoperative anatomic landmarks. Two cats died within 4 weeks after surgery of a nonrelated disease. In the remaining 5 cats, the hyperadrenocorticism went into both clinical and biochemical remission. Hyperadrenocorticism recurred in 1 cat after 19 months, but no other therapy was given and the cat died at home 28 months after surgery. CT evaluation of this cat had identified pituitary remnants 6 weeks after surgery. The main postoperative complications were oronasal fistula (1 cat), complete dehiscence of the soft palate (1 cat), and transient reduction of tear production (1 cat). One cat died at 6 months (undefined anemia), and another cat at 8 months (recurrent nose and middle ear infection secondary to soft palate dehiscence) after surgery. In the surviving 2 cats, the remission periods at the time of writing were 46 and 15 months. In the 2 cats with sufficient follow-up time, the concurrent diabetes mellitus disappeared, ie, insulin treatment could be discontinued at 4 weeks and 5 months after hypophysectomy. In all 7 cats, the histologic diagnosis was pituitary adenoma.

CONCLUSIONS

Microsurgical transsphenoidal hypophysectomy is an effective method of treatment for feline PDH in specialized veterinary institutions having access to advanced pituitary imaging techniques. Concurrent diabetes mellitus is usually reversible after hypophysectomy. Thorough presurgical screening for coexisting diseases is imperative.

CLINICAL RELEVANCE

PDH in cats can be effectively treated by hypophysectomy. The neurosurgeon performing hypophysectomy must master a learning curve and must be familiar with the most frequent complications of the operation to treat them immediately and effectively. Urinary C/C ratios are sensitive indicators for the assessment of remission and recurrence of hyperadrenocorticism.

[Syringomyelia associated with intracranial tumors. Case report and literature review]

A case of 39 years old woman with two intracranial meningiomas and syringomyelia is presented. Large right-sided tentorial meningioma in cerebellopontine angle and middle cranial fossa and small left sided sphenoid wing meningioma co-existed with secondary tonsillar herniation and large syringomyelic cavity in cervical and thoracic spinal cord. The patient had dissociated sensory loss on trunk and upper left extremity, muscle atrophy, left hand paresis, long tracts signs. After having done atlanto-occipital decompression, the intramedullary cavity collapsed and neurological symptoms resolved. Two months later large tentorial meningioma was successfully removed via occipito-suboccipital craniotomy with tentorial transsection. A review of the literature concerning syringomyelia secondary to intracranial tumours was done. To our knowledge this is the first such case described in which syringomyelia syndrome was the prominent symptom of the disease and two staged surgical procedure, first oriented at treatment of syringomyelia itself, was applied.

Neurofibromatosis type 1 and McCune-Albright syndrome occurring in the same patient

A patient with both neurofibromatosis type 1 (NF-1) and McCune-Albright syndrome is described. NF-1 and McCune-Albright are separate entities and this is the first report of a patient with clear evidence of both conditions.

Fetal venous circulation--an update on hemodynamics

The refinements of modern ultrasound techniques permit a renewed examination of old concepts of fetal circulation. The concept of preferential streaming of umbilical blood through the foramen ovale is verified by animal experiments, and ultrasound studies have confirmed that a similar mechanism operates in human fetuses. However, the normalized umbilical flow appears to be less in the human than in fetal sheep, and decreases with advancing gestational age (115 ml min-1 kg-1 at 20 and 64 mL min-1 kg-1 at 40 weeks). Compared to the 50% shunting of umbilical blood through the ductus venosus found in animal experiments, the degree of shunting in the human fetus under physiological conditions is considerably less, 30% at 20 weeks, which decreases to 18% at 32 weeks, suggesting a higher priority of the fetal liver than previously realized. Augmented pulsatility in the precordial veins, ductus venosus, and umbilical vein is an important clinical sign that is poorly understood. Recent fluid dynamic studies show that, apart from the pressure generated in the atria, it is the stiffness of the vessel wall, compliance, and notably, impedance which modify these waves. Particularly the substantial shift in impedance at the ductus venosus-umbilical vein junction causes wave reflection and reduced transmission of waves, the result being diminished or absent pulsation in the umbilical vein.

Presurgical evaluation: current role of invasive EEG

Our purpose was to review the current role of invasive and semi-invasive EEG in the presurgical evaluation of candidates for epilepsy surgery. The use of stereotactically implanted intracranial depth (stereo-EEG), subdural strip and grid, and foramen ovale electrodes, as well as intraoperative electrocorticography and electrical brain stimulation ("functional mapping") at the Epilepsy Center University Hospital Zurich, from 1984 to 1998, is analyzed. Advantages and disadvantages of the various intracranial EEG techniques are critically discussed. Out of 422 selective amygdalohippocampectomies performed in Zurich, 54% had non-invasive, 32% had semi-invasive, and 14% had invasive presurgical EEG evaluation. Because patients currently referred to our center increasingly present with a complex history of disease, i.e., constitute so-called "difficult cases", there is trend to combine several invasive and semi-invasive, pre- and intraoperative neurophysiological techniques.

Results of transsphenoidal surgery for Cushing's disease in patients with no histologically confirmed tumor

OBJECTIVE

Pathological confirmation of surgical resection of an adenoma for Cushing's disease is not always achieved. We reviewed our experience to determine the prognostic significance of this lack of confirmation regarding outcome, and we evaluate explanations for this situation.

METHODS

The records of all patients undergoing transsphenoidal surgery for Cushing's disease from 1992 to 1998 were reviewed, and those with no histological confirmation of tumor were identified. Information regarding preoperative and postoperative hormonal levels and clinical symptoms, preoperative magnetic resonance imaging data, intraoperative findings, and the number of reoperations were recorded.

RESULTS

There were 29 patients with no confirmation of tumor. Nineteen (66%) of these patients were cured with surgery and only one had a recurrence of disease, with an average follow-up of 38 months. An abnormality thought to represent an adenoma at the time of surgery was removed in 26 patients (90%). Preoperative magnetic resonance imaging suggested a discrete lesion in 21 patients (72%). Neither intraoperative impression nor magnetic resonance imaging appearance was correlated with outcome.

CONCLUSION

Patients with no histological confirmation of tumor after transsphenoidal surgery for Cushing's disease are likely to have a good outcome. The results do not differ significantly from reported cure rates in patients with confirmed adenomas. Possible explanations for this situation are discussed.

Expression of cathepsin K in chordoma

Invasive growth of chordoma is accompanied by severe destruction of adjacent bone tissue, a fact that requires high proteolytic activity at the tumor invasion fronts. In this context, cathepsin K is a candidate molecule. It is a protease with high collagenolytic and elastinolytic activity and previously thought to be restricted to osteoclasts and osteoclast-mediated bone resorption. In this study, 44 cases of chordoma of sphenooccipital localization, and 10 embryo-fetal specimens including chorda dorsalis were studied immunohistochemically for their expression of cathepsin K. In 4 additional snap-frozen chordoma cases, the enzyme expression was investigated by reverse transcription polymerase chain reaction and enzyme histochemistry. Ten chondrosarcomas of the skull base served as controls. Various concentrations of cathepsin K mRNA could be seen in all snap-frozen chordoma specimens. The protease was immunohistochemically expressed by the tumor cells. The immunoreactions were accentuated at the tumor invasion fronts. Enzyme histochemistry indicated a strong tumor cell-associated cathepsin K activity in invasive tumor components. In contrast to chordoma, cathepsin K was not significantly expressed in chorda dorsalis and chondrosarcoma of the skull base. In chondrosarcoma, protease expression was limited to osteoclastic cells localized between infiltrative tumor components and regular bone trabeculae. This study shows the significant expression and activity of cathepsin K in chordoma and implicates an important and direct role of this protease in the infiltrative growth of this tumor. This protease expression occurred during neoplastic transformation and did not appear in chorda dorsalis.

Complications of trans-sphenoidal surgery: the Wellington experience

BACKGROUND

All patients who underwent trans-sphenoidal surgery between January 1984 and December 1998 were reviewed to assess morbidity resulting from this operation.

METHODS

There were 185 operations on 165 patients. The operative approach was sublabial in 80 cases and transnasal in 105. One surgeon (VB) performed the vast majority of operations.

RESULTS

Complications included nasal perforation (7.6%), transient diabetes insipidus (4.9%), permanent diabetes insipidus (3.8%), cerebrospinal fluid fistula (4.3%), donor site haematoma (2.2%) and residual tumour haemorrhage (1.6%) causing ophthalmoplegia (1.1%) and loss of vision (1.1%). Other complications included epistaxis (1.1%), meningitis (0.5%) and sinusitis (0.5%). Injury to the anterior superior alveolar nerve also occurred in the sublabial approach in 6.3% of patients. There were no perioperative deaths.

CONCLUSIONS

There is a small but significant risk of a number of complications that should be considered for informed consent of this procedure.

Precise cannulation of the foramen ovale in trigeminal neuralgia complicating osteogenesis imperfecta with basilar invagination: technical case report

OBJECTIVE AND IMPORTANCE

Trigeminal neuralgia is a rare feature of basilar invagination, which is itself a complication of osteochondrodysplastic disorders. Microvascular decompression is an unattractive option in medically refractory cases. The conventional percutaneous approach to the trigeminal ganglion is anatomically impossible because the foramen ovale points inferiorly and posteromedially. We report a new technique for image-guided trigeminal injection in a patient with basilar invagination complicating osteogenesis imperfecta.

CLINICAL PRESENTATION

A 26-year-old woman with osteogenesis imperfecta presented with a 3-year history of typical left maxillary division trigeminal neuralgia, which was poorly controlled by carbamazepine at the maximum tolerated dose. She had obvious cranial deformities, left optic atrophy, delayed left eye closure, tongue atrophy, but normal facial sensation and corneal reflexes. A computed tomographic scan and magnetic resonance imaging confirmed severe basilar invagination.

TECHNIQUE

Frameless stereotactic glycerol injection of the left trigeminal ganglion was performed under general anesthesia using the infrared-based EasyGuide Neuro system (Philips Medical Systems, Best, The Netherlands) with magnetic resonance imaging and computed tomographic registration. The displaced and distorted left foramen ovale was cannulated via a true frameless stereotactic method with the trajectory determined by virtual pointer elongation. The needle placement was confirmed with injection of contrast medium into the trigeminal cistern. The path needed to enter the foramen traversed the right cheek, soft palate, and left tonsil. The patient went home pain-free with a preserved corneal reflex and no complications.

CONCLUSION

Frameless stereotaxy allows customization to individual patient anatomy and may be adapted to a variety of percutaneous procedures used in areas where the anatomy is complex.

[Temporo-spheno-orbital meningioma. An unusual cause of exophthalmos. Report of one case]

We report the case of a 48-year-old woman with no prior medical history who developed headache and unilateral exophthalmos for 6 months. Clinical and radiographic findings detailed the intracranial extension of a temporo-spheno-orbital meningioma. Histological diagnosis was established after curative neurosurgery. This case recalls the characteristic features of temporo-spheno-orbital meningiomas.

Pre-and post-operative respiratory assessment of acromegalics with sleep apnea--bedside oximetric study for transsphenoidal approach

PURPOSE

Although routine mechanical nasal packing after transsphenoidal surgery (TS) is thought to increase respiratory disorders during sleep, there has been little in the literature about the pre- and post-operative airway assessment of acromegalics with sleep apnea (SA). We describe 4 acromegalic patients with SA, who underwent transsphenoidal surgery. METHODS AND CASES: The patients were all men, aged from 47 to 59 years. The pre- and post-operative sleep study consisted with a computer calculated oximetry parameter of oxygen desaturation index (ODI), which was defined as the number/hour of oxygen desaturation episodes exceeding 4% from the base line (normal range < 15). The postoperative (postop.) sleep study was carried out from the 1st postop. day to the 8th day, for 1 to 8 days, varying for each patient.

RESULTS

Only the worst postop. result is shown. Patient 1 had 2 operations, 2 years apart. ODI was 39.6 before the 1st operation and 45.9 postop.. In the second operation ODI was 21.8 preoperatively (preop.) and 57.9 postop.. Preop. and postop. ODI was 18.1 and 22.2 in patient 2, 21.6 and 22.5 in patient 3 and 45.5 and 18.9 in patient 4, respectively. ODI of patient 4 was 39.6, 3 weeks later.

CONCLUSION

Our data showed that the postop. oxymetric study commonly showed worse results in acromegalics with nasal packing. The better result of patient 4 was probably due to a postop. sleepless state. REM sleep usually increases in the first several postop. days, when cardiopulmonary complications are more likely to occur. Since acromegalics with severe SA and postop. nasal packing may more readily suffer from cardiopulmonary complications, postoperative meticulous respiratory monitoring and care should be mandatory.

Cranial base surgical techniques for large sphenocavernous meningiomas: technical note

OBJECTIVE

Large meningiomas arising from the dura covering the sphenoid ridge present surgical challenges because of frequent involvement of the carotid artery and its branches, the optic nerve and tract, the superior orbital fissure, and cavernous sinus structures. To circumvent the inherent difficulties of a traditional approach strategy, cranial base approaches were applied to: 1) isolate and interrupt the major blood supply as an initial step, 2) minimize brain retraction, and 3) isolate the neurovascular structures exiting the tumor at the cranial base to protect and better separate them.

METHODS

Six patients were treated with such a strategy in the past 2 years (five women and one man, ages 34-69 yr). All tumors measured at least 5 cm in their greatest diameter and arose at the sphenoid ridge. All tumors extended posteriorly to involve the cavernous sinus to varying degrees. In two patients a frontotemporal bone flap was used; in two patients, a transzygomatic approach was used; and in the remaining two patients, an orbitozygomatic strategy was used. Extensive bone removal at the cranial base was performed in all cases.

RESULTS

Four patients had gross total resections, and two were subtotal owing to invasion of the cavernous sinus or the middle cerebral artery. There were no permanent cranial nerve deficits; however, two patients sustained transient IIIrd nerve paresis. Two patients postoperatively developed transient cerebral edema that required intensive treatment. All six patients had good outcomes, resuming independent activity by 3 months after surgery.

CONCLUSION

Contemporary cranial base surgical techniques have a role in the treatment of large sphenoid ridge meningiomas. These strategies result in safe resection with low morbidity and obviate the need in most cases for preoperative embolization. The anatomic foundation for using these approaches is discussed.

[Sphenotemporal aneurysmal bone cyst. A new case and review of the literature]

Aneurysmal bone cysts (ABC) are benign tumors of the bones, formed by multiple cysts filled with blood and eroding the bone. They are rarely located at the skull. We report a case of a right temporal ABC in a 5-year-old girl. On admission, the physical examination showed a tough and fixed tumor, with no inflammatory signs nor vascular characteristics. The neurological examination was normal. Imaging studies showed an heterogeneous extracerebral mass, eroding the temporal bone and the greater wing of the sphenoid bone. The treatment consisted in an extensive tumor resection, associated with reconstructive surgery. The outcome was uneventful (follow-up 27 months). We underline the pathogenetic, diagnostic and therapeutic features of this condition.

Inflammatory pseudotumor of the fossa pterygopalatina: diagnosis and treatment

Pseudotumor is a term used to describe a space-occupying inflammatory lesion of unknown etiology that clinically simulates a neoplastic process. Pseudotumors of the fossa pterygopalatina and fossa infratemporalis are very rare. In this paper, we describe a patient who developed a pseudotumor in the left fossa pterygopalatina, secondary to an unclassified autoimmune disease, which caused progressive left-sided facialdynia and swelling. The tumor was detected with somatostatin receptor scintigraphy. The lesion was refractory to steroids, also in combination with azathioprine, as well as to surgical intervention. An excellent clinical response was observed after cyclosporine was added. This case is presented here in order to draw attention to the use of somatostatin receptor scintigraphy as a diagnostic tool in visualizing pseudotumors and to document a case that responded excellently to treatment with a combination of low-dose cyclosporine and steroids.

[Association of spheno-orbital dysplasia with plexiform neuroma in von Recklinghausen's neurofibromatosis]

We report a case of plexiform neurofibroma of the upper eyelid associated with spheno-orbital dysplasia in a 18-year-old woman with von Recklinghausen neurofibromatosis. Visual acuity was 20/40 in the right eye and 20/20 in the left. Plexiform neurofibroma involving the right upper eyelid was associated with mild ptosis and ipsilateral facial hypertrophy. Biomicroscopic examination showed lisch nodules. Funduscopic examination, visual field and neurologic examinations were normal. Café au lait spots involved the trunk with neck plexiform neurofibroma. Computed tomography disclosed spheno-orbital dysplasia. The patient's status remained unchanged at 6 months follow-up. Cranial features of von Recklinghausen neurofibromatosis are found in 3 to 7% of patients. In patients with plexiform neurofibroma of the eyelid the ophthalmologist should look for associated spheno-orbital dysplasia.

Direct postoperative and follow-up results of transsphenoidal surgery in 19 acromegalic patients pretreated with octreotide compared to those in untreated matched controls

In this study 19 patients were preoperatively treated with octreotide for 1-17 months (mean, 5 months), with doses from 150-1500 microg daily, and those patients were matched to 19 untreated patients with comparable tumor classification and preoperative serum GH concentrations. Octreotide was started at 300 microg daily by s.c. injections or continuous sc infusion using a pump in increasing doses, depending on the responses of the serum GH and insulin-like growth factor I (IGF-I) concentrations. During pretreatment, seven patients achieved a serum GH concentration below 5 mU/L, whereas six patients normalized their serum IGF-I. Postoperatively, a serum GH concentration below 5 mU/L was achieved in 15 pretreated and 14 untreated patients, a normal serum IGF-I level (<2 SD) was achieved in 10 pretreated and 15 untreated patients, and normal serum GH suppression during GTT was reached in 12 treated and 14 control patients. No differences were found in complication rate or incidence of hypopituitarism caused by surgery. Adjuvant therapy was required in 7 treated and 5 untreated patients. At follow-up examination, 5.7 and 4 yr postoperatively, 10 pretreated and 12 control patients could be considered cured by surgery only, according to our criteria for remission (serum GH, <5 mU/L; normal GH suppression and normal serum IGF-I). In summary, we found no difference in direct postoperative and follow-up results of transsphenoidal surgery between pretreated patients and untreated patients. This finding is in discordance with other studies, which have claimed a beneficial effect of octreotide pretreatment.

Giant cell reparative granuloma: a case report

Giant cell reparative granuloma (GCRG) is an infrequent benign lesion with undetermined etiopathogenesis affecting the maxillary and mandibular bone and, rarely, the skull. It is also extremely rare in the sphenoid bone. GCRG is usually diagnosed by histologic examination of bone lesions. We report a case of GCRG originating from the sphenoid bone. Computerized tomography revealed an expansile lesion with thinning or destruction of the cortical bone. The lesion itself was slightly hyperdense with good but inhomogeneous contrast enhancement. Reported magnetic resonance image findings showed hyperintensity on both T1-weighted and T2-weighted images and variable contrast enhancement. Plain skull radiographs usually reveal a lytic lesion within the bone.

[Giant cell tumor originating in the sphenoid bone: a case report]

The authors report a case of giant cell tumor originating in the sphenoid bone. A 29-year-old woman presented with headache and diplopia. Bilateral ophthalmoplegia developed and MRI showed rapid growth of the tumor in spite of transnasal removal and conventional radiation therapy. The second transnasal surgery was performed 3 weeks after completion of radiotherapy. The symptoms were relieved except for right abducens palsy. Chemotherapy with cisplatin and etoposide was started after the second operation. The patient regained full ocular movement several months after the operation. Clinical remission has continued for four years. We conclude that the combination of repeated operations in the initial phase of rapid tumor growth, irradiation and chemotherapy is important to achieve tumor control.

Anterior clinoidal meningiomas: report of a series of 33 patients operated on through the pterional approach

Between 1985 and 1995, 33 cases of clinoidal meningioma were surgically treated by pterional approach. In 6 cases, according to the grading scale of Al-Mefty, the lesions were group I, having originated from the lower part of the clinoid; in 22 cases, the lesions were group II, having originated from the upper or lateral part of the clinoid process; and in 5 cases, the lesions were group III since they arose from the optic foramen. Postoperatively, 17 patients showed an improvement, 4 were unchanged, and 6 presented further deficits. Five patients died after surgery: two from pulmonary thromboembolism, one from myocardial infarction, one from hematoma of the operative field, and one from cerebral ischemia after severe vasospasm of the internal carotid artery (unresponsive to treatment). The mean follow-up was 53.7 months (range 12-108 months) and included 19 patients. During this period, there were five recurrences, and three patients underwent resection again and showed no signs of tumor regrowth 1 year later; one patient who did not undergo resection again due to his age and poor general conditions died 3 years after onset of the recurrence; the last patient has so far refused a second operation. The clinical, diagnostic, and therapeutic aspects of this not infrequent pathology are discussed in the light of our experience and the pertinent literature.

Mucocele involving the anterior clinoid process: MR and CT findings

We report two patients with surgically proved mucoceles involving the anterior clinoid process. One patient had a mucocele of an Onodi cell and the other had a mucocele isolated to the anterior clinoid process. The MR signal was increased on both T1- and T2-weighted images in the first patient but was isointense on both sequences in the second patient, a finding that resulted in misdiagnosis. The developmental and anatomic features, as well as the diagnostic pitfalls, are discussed.

Primary spheno-orbital angiosarcoma: case report and review of the literature

OBJECTIVE

Angiosarcoma is a rare neoplasm that uncommonly involves the cranium. We report the second case in the literature of a primary right spheno-orbital malignant angiosarcoma.

CLINICAL PRESENTATION

This 43-year-old man experienced a 3-month history of rapid growing temporal mass. The results of his neurological examination were normal. Neuroimaging revealed an intensively enhanced right spheno-orbital lesion, with destruction of the greater wing of the sphenoid bone and extension into the orbit, the infratemporal fossa, and the temporal fossa with infiltration of the dura mater but without parenchymal abnormality.

INTERVENTION

The tumor was first biopsied and then totally removed, with exenteration of the right eye. The histological features were typical of angiosarcoma with immunohistochemical evidence of Factor VIII-related antigen produced by tumor cells. Neither radiotherapy nor chemotherapy was performed. The patient remained well during 16 months of follow-up, without evidence of recurrence on magnetic resonance images.

CONCLUSION

We emphasize the benefit of wide surgical resection without systematic complementary treatment (radiotherapy and/or chemotherapy) in a case of primary angiosarcoma of the cranium. The literature is reviewed.

Truncal anaesthesia of the maxillary nerve for outpatient surgically assisted rapid maxillary expansion

We present our experience of transcutaneous truncal anaesthesia of the maxillary nerve in association with transmucosal anaesthesia of the sphenopalatine ganglion in surgically assisted rapid maxillary expansion. Twelve patients with a skeletal transverse discrepancy of the maxilla were treated in our department from 1994 to 1995. Maxillary transcutaneous nerve block was done with a Quincke 8 cm spinal needle together with transmucosal anaesthesia of the sphenopalatine ganglion. Mepivacaine without adrenaline and sodium bicarbonate 1/10 was used for truncal anaesthesia and lidocaine-prilocaine cream for transmucosal anaesthesia. A Le Fort I osteotomy, lateral nasal wall osteotomy, pterygomaxillary osteotomy, and a palatal osteotomy were done for all patients before the maxillary expansion. Total anaesthesia of the maxillary area facilitated the operations and appreciably reduced the amount of postoperative pain. The ease of achieving effective anaesthesia before and after operation and the absence of side-effects make this form of anaesthetic particularly useful in surgically assisted rapid maxillary expansion.

Topographical reliability of mesio-temporal sources of interictal spikes in temporal lobe epilepsy

PURPOSE

Localization of hippocampal paroxysmal activities in temporal lobe epilepsy (TLE) by means of dipole modeling has often been criticized because of the supposed inaccuracy of this technique in localizing deep sources of EEG signals. This study aimed at assessing the relevance of mesio-temporal dipoles, as identified by modeling of scalp recorded spikes in TLE.

METHODS

Surface and depth EEG activities were simultaneously recorded using scalp and intracranial electrodes implanted through the foramen ovale (FO) in 3 patients with refractory TLE seizures. Intracranial FO spikes were used as triggers for scalp EEG averaging. The averaged signals were modeled by current dipoles, the localization of which were fused with patients' 3D-MRI.

RESULTS

Individual FO spikes were undetectable on visual analysis of raw scalp EEG but were reflected by low-amplitude scalp EEG transients on averaged signal. Dipole modeling of this EEG deflection consistently identified a mesio-limbic source in a position close to that of the FO pole recording the intracranial spike with its maximal amplitude.

CONCLUSION

This result suggests that mesio-temporal sources can be accurately localized by modeling the signals recorded on the scalp, thus validating the anatomical and clinical relevance of hippocampal sources identified by modeling scalp interictal averaged spikes in TLE.

Neuronal complexity loss in interictal EEG recorded with foramen ovale electrodes predicts side of primary epileptogenic area in temporal lobe epilepsy: a replication study

PURPOSE

To investigate whether a correct lateralization of the primary epileptogenic area by means of neuronal complexity loss analysis can be obtained from interictal EEG recordings using semi-invasive foramen ovale electrodes. In a previous study with recordings from intrahippocampal depth and subdural strip electrodes it was shown that the dynamics of the primary epileptogenic area can be characterized by an increased loss of neuronal complexity in patients with unilateral temporal lobe epilepsy (TLE).

METHODS

Neuronal complexity loss analysis was applied. This analysis method is derived from the theory of nonlinear dynamics and provides a topological diagnosis even in cases where no actual seizure activity can be recorded. We examined interictal EEG recorded intracranially from multipolar foramen ovale electrodes in 19 patients with unilateral TLE undergoing presurgical evaluation.

RESULTS

The primary epileptogenic area was correctly lateralized in 16 of the 19 investigated patients. The misclassification of the side of seizure onset in three patients might be attributed to the larger distance between the foramen ovale electrodes and the mesial temporal structures as compared to intrahippocampal depth electrodes.

CONCLUSIONS

Our results confirm the previous findings and provide further evidence for the usefulness of nonlinear time-series analysis for the characterization of the spatiotemporal dynamics of the primary epileptogenic area in mesial temporal lobe epilepsy.

Anatomical considerations on the discomalleolar ligament

A study was carried out on the discomalleolar ligament by dissection of adult human cadavers. The ligament corresponds to the most internal portion of the superior lamina of the temporomandibular joint capsule. It extends from the posterointernal portion of the temporomandibular joint disc, penetrates the petrotympanic fissure and reaches the malleus of the middle ear. Because of its morphology and anatomical arrangement the discomalleolar ligament should be considered as an intrinsic ligament of the temporomandibular joint and distinguished from the tympanic portion of the sphenomandibular ligament (anterior ligament of the malleus).

Giant cell tumor of the sphenoid bone: long-term follow-up of two cases after chemotherapy

BACKGROUND

Giant cell tumors rarely occur in the sphenoid bone. When they do occur in the base of the skull, surgical treatment is frequently difficult and therefore, the use of adjuvant therapy is important. However, there remains no optimal management regimen for giant cell tumors of the sphenoid bone.

CASE DESCRIPTION

Two cases of a giant cell tumor involving the sphenoid bone that responded well to chemotherapy using adriamycin after a partial removal of the tumor are presented. In the first patient, the tumor was partially removed via a transcranial subfrontal approach and a transnasal transsphenoidal approach. In the second patient, the tumor was partially removed through a transcranial subfrontal approach. Both tumors demonstrated histologic features typical of giant cell tumors. The patients subsequently received adjuvant chemotherapy using adriamycin alone in the first patient, and chemotherapy combined with radiotherapy in the second patient. Partial regression of the tumors was later confirmed on a computed tomography (CT) scan after chemotherapy. In both patients, tumors have been stable for more than 12 years despite an incomplete removal of the tumors.

CONCLUSION

Based on the above findings, postoperative adjuvant chemotherapy using adriamycin may be effective for incompletely resected giant cell tumors of the sphenoid bone.

Cost-efficient localization of seizures of mesiotemporal onset with foramen-ovale electrodes

Foramen ovale (FO) electrodes can identify mesiotemporal lobe (MTL) seizure onsets but are infrequently used in the USA. Ten patients with presumed MTL ictal onset, unlocalized noninvasively, had FO electrodes inserted during long term monitoring for epilepsy. Placement was facilitated by intraoperative use of oblique submental and modified Caldwell view fluoroscopy. Eighty percent of patients had ictal localization by FO electrodes. This led to anterior temporal lobectomy in six with 83% being seizure free after follow-up of 20-32 months. The mean total costs of placing these electrodes was approximately half that of subdural strips and a quarter that of depth electrodes. Foramen ovale electrodes represent a cost-effective and efficient method of seizure localization when noninvasive workup suggests but is not definitive for MTL origin.

Blocks of the foramen rotundum and the oval foramen: a reappraisal of extraoral maxillary and mandibular nerve injections

OBJECTIVE

To present our experience of regional anaesthesia with blocks of the foramen rotundum and the oval foramen.

DESIGN

Open study.

SETTING

University Hospital, Beograd, Yugoslavia.

SUBJECTS

107 patients who underwent 58 maxillary and 49 mandibular nerve blocks.

INTERVENTIONS

Injection of 2% lignocaine with adrenaline 1/80,000 with an 18 G venflon or 20 G spinal needle.

MAIN OUTCOME MEASURES

Quality of anaesthesia and morbidity.

RESULTS

49 of the 58 maxillary (84%) and 45 of the 49 mandibular (92%) nerve blocks were successful (no sensitivity to pinprick in the distribution of the injected nerve and a painless operation). There were 17 complications (26%), 8 in the maxillary and 9 in the mandibular group. All complications were minor and transient, and 6 could be attributed to anhydrous glycerol rather than the injection technique itself.

CONCLUSION

Blocks of the foramen rotundum and the oval foramen achieve good regional anaesthesia in the maxillofacial region.

[Temporo-sphenoidal giant cell tumors, apropos of a case]

The authors report an extremely rare case: a bony giant cell tumour in the temporo-sphenoidal region presenting with hearing loss and vertigo. The main characteristics of these tumours are given, together with a literature review. This is the 5th published case of this tumour in the temporo-sphenoidal region. The treatment of these tumours is essentially surgical, and the authors emphasise the use of Sekhar's approach.

[Assessment of prognosis factors in the cure of Cushing's disease surgically treated via a +septotransphenoidal approach]

INTRODUCTION

In Cushing's disease (CD) pituitary surgery or radiotherapy has been proposed by some authors, when plasmatic cortisol after surgery is not clearly low.

AIM

To assess if the different prognostic factors, specially plasmatic cortisol seven days after surgery and/or hypocortisolism phase are predictive of the CD outcome.

METHODS

From 1988, 11 women with CD underwent 13 transsphenoidal microsurgery, because two patients relapsed. The mean age of patients was 27 years (11-52). Plasmatic cortisol was measured seven days after pituitary surgery, and since 45 days, every three-six months, basal plasmatic cortisol and after ACTH and urinary free cortisol were determined.

RESULTS

Follow-up evaluations ranged from 18-84 months (median, 38 months). After pituitary surgery in 13 cases the cumulative remission was 100%, two cases relapsed. In 10 cases plasmatic cortisol seven days after surgery was less than 137 nmol/l and in three cases higher than 137 nmol/l. Three cases did not presented hypocortisolism phase. The two patients who relapsed, one was after eight months of pituitary surgery an previously showed low plasmatic cortisol and the other relapse 25 months after pituitary surgery without low cortisol plasmatic levels.

CONCLUSION

Remission in CD can happen either low or normal plasmatic cortisol levels seven days posttreatment or without hypocortisolism phase. Ours findings ascribe new importance to the different presentations after treatment of CD, and patients with these findings are not a risk for relapse and pituitary surgery or irradiation would not be early indicated.

Endoscopic endonasal transsphenoidal surgery: experience with 50 patients

An endoscope was used in transsphenoidal surgery and eventually replaced the operating microscope as the tool for visualization. This study focuses on 50 patients (28 females and 22 males) with a median age of 38 years (range 14-88 years). Initially, four patients underwent operation via a sublabial-transseptal approach using a rigid endoscope in conjunction with an operating microscope. The 48 subsequent operations were performed through a nostril using only rigid endoscopes. Forty-four patients had pituitary adenomas and six had various other lesions. Thirteen patients had microadenomas, 16 had intrasellar macroadenomas, nine had macroadenomas with suprasellar extension, and six had invasive macroadenomas involving the cavernous sinus. Seven patients had recurrent pituitary adenomas and 25 had hormone-secreting adenomas (eight patients with Cushing's disease and 17 patients with prolactinomas). Among the eight patients with Cushing's disease, seven had resolution of hypercortisolism clinically and chemically. Of the 17 patients with prolactinomas, 10 improved clinically with normal serum prolactin levels, four improved clinically with elevated serum prolactin levels, and three had residual tumors in the cavernous sinus. Among the 19 patients with nonsecreting adenomas, 16 underwent total resection and three subtotal resection leaving residual tumor in the cavernous sinus. Postoperatively, all patients who had undergone endonasal endoscopic surgery had unobstructed nasal airways with minimal discomfort. More than half of the patients required only an overnight hospitalization.

[Cushing disease in children and in adolescents. Therapeutic results]

BACKGROUND

Trans-sphenoidal surgery is currently the treatment of choice for Cushing's disease in children.

PATIENTS AND METHODS

The results obtained in 20 consecutive patients referred to the Pediatric Endocrinology Department of hôpital Saint-Vincent-de-Paul are reported.

RESULTS

A remission of Cushing's disease was observed in 12/16 (75%) patients in whom surgery was the first treatment. Among these 12 patients, three relapsed (25%) 21 to 80 months after surgery. Four patients were initially treated with steroid synthesis inhibitors: three of those patients were subsequently operated on and their disease remitted. Among the seven patients in whom surgery failed (primary failure or relapse), two were reoperated and also remitted. Taken together, 21 operations were performed and resulted in four immediate failures (19%), three relapses (14%) and 14 long-term remissions (67%, follow-up 40 +/- 35 months). None of the biological, radiological or operative criteria were predictive of the therapeutic results.

CONCLUSION

Our results illustrate the efficacy and limits of trans-sphenoidal surgery for Cushing's disease of children and emphasize the need for a very long follow-up of these patients. Treatment of patients in whom surgery has failed (initially or secondarily) is particularly difficult and requires a multidisciplinary approach.