Surgical Treatment of Spinal Meningiomas in the Elderly (≥75 Years): Which Factors Affect the Neurological Outcome? An International Multicentric Study of 72 Cases

(1) Background: With the increasing life expectancy in the Western world, an increasing number of old patients presents with spinal meningioma. Considering the benign nature of these tumors, the functional outcome remains of great importance, since more people reach old age in general conditions of well-being and satisfactory autonomy. (2) Methods: We conducted an international multicenter retrospective study to investigate demographic, clinical and radiological data in a population of elderly patients (≥75 years of age) undergoing surgery for SM from January 2000 to December 2020 in four European referral centers. The aim was to identify prognostic and predictive factors for a good postoperative functional outcome. (3) Results: 72 patients were included in the study. Complete tumor resection (Simpson I or II) was achieved in 67 (95.7%) cases. Intraoperative complications were reported in 7 (9.9%) patients while postoperative complications were found in 12 (16.7%). An excellent general postoperative status (McCormick I and II) was achieved in 65.3%. Overall, surgical resection had a good impact on patients’ functional outcome (86.1% either showing an improvement or maintaining a good preoperative status). Uni- and multivariate analyses found that both age and preoperative modified McCormick independently correlated with relative outcome (coeff = −0.058, p = 0.0251; coeff = 0.597, p < 0.0001) and with postoperative status (coeff = 0.058, p = 0.02507; coeff = 0.402, p = 0.00027), respectively. (4) Conclusions: Age and preoperative modified McCormick were found to be independent prognostic factors. Nevertheless, advanced age (≥75), per se, did not seem to contraindicate surgery, even in those with severe preoperative neurological deficits. The functional results sustain the need for surgical resection of SM in the elderly.

The "STARS-CASCADE" Study: Virtual Reality Simulation as a New Training Approach in Vascular Neurosurgery

OBJECTIVE

Surgical clipping has become a relatively rare procedure in comparison to endovascular exclusion of cerebral aneurysms. Consequently, there is a declining number of cases where young neurosurgeons can practice clipping. For this reason, we investigated the application of a new 3-dimensional (3D) simulation and rehearsal device, Surgical Theater, in vascular neurosurgery.

METHODS

We analyzed data of 20 patients who underwent surgical aneurysm clipping. In 10 cases, Surgical Theater was used to perform the preoperative 3D planning (CASCADE group), while traditional imaging was used in the other cases (control group). Preoperative 3D simulation was performed by 4 expert and 3 junior neurosurgeons (1 fellow, 2 residents). During postoperative debriefings, expert surgeons explained the different aspects of the operation to their younger colleagues in an interactive way using the simulator. Questionnaires were given to the surgeons to get qualitative feedback about the simulator, and the junior surgeons' performance at simulator was also analyzed.

RESULTS

There were no differences in surgery outcomes, complications, and surgical duration (P > 0.05) between the 2 groups. Senior neurosurgeons performed similarly when operating at the simulator as compared with in the operating room, while junior neurosurgeons improved their performance at the simulator after the debriefing session (P < 0.005).

CONCLUSIONS

Surgical Theater proved to be realistic in replicating vascular neurosurgery scenarios for rehearsal and simulation purposes. Moreover, it was shown to be useful for didactic purposes, allowing young neurosurgeons to take full advantage and learn from senior colleagues to become familiar with this demanding neurosurgical subspecialty.

Is Contrast Medium Really Needed for Follow-up MRI of Untreated Intracranial Meningiomas?

BACKGROUND AND PURPOSE

Recent concerns relating to tissue deposition of gadolinium are favoring the use of noncontrast MR imaging whenever possible. The purpose of this study was to assess the necessity of gadolinium contrast for follow-up MR imaging of untreated intracranial meningiomas.

MATERIALS AND METHODS

One-hundred twenty-two patients (35 men, 87 women) with meningiomas who underwent brain MR imaging between May 2007 and May 2019 in our institution were included in this retrospective cohort study. We analyzed 132 meningiomas: 73 non-skull base (55%) versus 59 skull base (45%), 93 symptomatic (70%) versus 39 asymptomatic (30%). Fifty-nine meningiomas underwent an operation: 54 World Health Organization grade I (92%) and 5 World Health Organization grade II (8%). All meningiomas were segmented on T1 3D-gadolinium and 2D-T2WI. Agreement between T1 3D-gadolinium and 2D-T2WI segmentations was assessed by the intraclass correlation coefficient.

RESULTS

The mean time between MR images was 1485 days (range, 760-3810 days). There was excellent agreement between T1 3D-gadolinium and T2WI segmentations (P < .001): mean tumor volume (T1 3D-gadolinium: 9012.15 [SD, 19,223.03] mm³; T2WI: 8528.45 [SD, 18,368.18 ] mm³; intraclass correlation coefficient = 0.996), surface area (intraclass correlation coefficient = 0.989), surface/volume ratio (intraclass correlation coefficient = 0.924), maximum 3D diameter (intraclass correlation coefficient = 0.986), maximum 2D diameter in the axial (intraclass correlation coefficient = 0.990), coronal (intraclass correlation coefficient = 0.982), and sagittal planes (intraclass correlation coefficient = 0.985), major axis length (intraclass correlation coefficient = 0.989), minor axis length (intraclass correlation coefficient = 0.992), and least axis length (intraclass correlation coefficient = 0.988). Tumor growth also showed good agreement (P < .001), estimated as a mean of 461.87 [SD, 2704.1] mm³/year on T1 3D-gadolinium and 556.64 [SD, 2624.02 ] mm³/year on T2WI.

CONCLUSIONS

Our results show excellent agreement between the size and growth of meningiomas derived from T1 3D-gadolinium and 2D-T2WI, suggesting that the use of noncontrast MR imaging may be appropriate for the follow-up of untreated meningiomas, which would be cost-effective and avert risks associated with contrast media.

Benefits of clinical criteria and high-throughput sequencing for diagnosing children with syndromic craniosynostosis

An accurate diagnosis of syndromic craniosynostosis (CS) is important for personalized treatment, surveillance, and genetic counselling. We describe detailed clinical criteria for syndromic CS and the distribution of genetic diagnoses within the cohort. The prospective registry of the Norwegian National Unit for Craniofacial Surgery was used to retrieve individuals with syndromic CS born between 1 January 2002 and 30 June 2019. All individuals were assessed by a clinical geneticist and classified using defined clinical criteria. A stepwise approach consisting of single-gene analysis, comparative genomic hybridization (aCGH), and exome-based high-throughput sequencing, first filtering for 72 genes associated with syndromic CS, followed by an extended trio-based panel of 1570 genes were offered to all syndromic CS cases. A total of 381 individuals were registered with CS, of whom 104 (27%) were clinically classified as syndromic CS. Using the single-gene analysis, aCGH, and custom-designed panel, a genetic diagnosis was confirmed in 73% of the individuals (n = 94). The diagnostic yield increased to 84% after adding the results from the extended trio-based panel. Common causes of syndromic CS were found in 53 individuals (56%), whereas 26 (28%) had other genetic syndromes, including 17 individuals with syndromes not commonly associated with CS. Only 15 individuals (16%) had negative genetic analyses. Using the defined combination of clinical criteria, we detected among the highest numbers of syndromic CS cases reported, confirmed by a high genetic diagnostic yield of 84%. The observed genetic heterogeneity encourages a broad genetic approach in diagnosing syndromic CS.

Petroclival meningiomas: update of current treatment and consensus by the EANS skull base section

BACKGROUND

The optimal management of petroclival meningiomas (PCMs) continues to be debated along with several controversies that persist.

METHODS

A task force was created by the EANS skull base section along with its members and other renowned experts in the field to generate recommendations for the management of these tumors. To achieve this, the task force reviewed in detail the literature in this field and had formal discussions within the group.

RESULTS

The constituted task force dealt with the existing definitions and classifications, pre-operative radiological investigations, management of small and asymptomatic PCMs, radiosurgery, optimal surgical strategies, multimodal treatment, decision-making, and patient's counselling.

CONCLUSION

This article represents the consensually derived opinion of the task force with respect to the management of PCMs.

The Perplexity Surrounding Chiari Malformations - Are We Any Wiser Now?

Chiari malformations are a diverse group of abnormalities of the brain, craniovertebral junction, and the spine. Chiari 0, I, and 1.5 malformations, likely a spectrum of the same malformation with increasing severity, are due to the inadequacy of the para-axial mesoderm, which leads to insufficient development of occipital somites. Chiari II malformation is possibly due to nonclosure of the caudal end of the neuropore, with similar pathogenesis in the rostral end, which causes a Chiari III malformation. There have been significant developments in the understanding of this complex entity owing to insights into the pathogenesis and advancements in imaging modalities and neurosurgical techniques. This article aims to review the different types and pathophysiology of the Chiari malformations, along with a description of the various associated abnormalities. We also highlight the role of ante- and postnatal imaging, with a focus on the newer techniques in the presurgical evaluation, with a brief mention of the surgical procedures and the associated postsurgical complications.

Filling the gap between the OR and virtual simulation: a European study on a basic neurosurgical procedure

BACKGROUND

Currently available simulators are supposed to allow young neurosurgeons to hone their technical skills in a safe environment, without causing any unnecessary harm to their patients caused by their inexperience. For this training method to be largely accepted in neurosurgery, it is necessary to prove simulation efficacy by means of large-scale clinical validation studies.

METHODS

We correlated and analysed the performance at a simulator and the actual operative skills of different neurosurgeons (construct validity). We conducted a study involving 92 residents and attending neurosurgeons from different European Centres; each participant had to perform a virtual task, namely the placement of an external ventricular drain (EVD) at a neurosurgical simulator (ImmersiveTouch). The number of attempts needed to reach the ventricles and the accuracy in positioning the catheter were assessed.

RESULTS

Data suggests a positive correlation between subjects who placed more EVDs in the previous year and those who get better scores at the simulator (p = .008) (fewer attempts and better surgical accuracy). The number of attempts to reach the ventricle was also analysed; senior residents needed fewer attempts (mean = 2.26; SD = 1.11) than junior residents (mean = 3.12; SD = 1.05) (p = .007) and staff neurosurgeons (mean = 2.89, SD = 1.23). Scoring results were compared by using the Fisher's test, for the analysis of the variances, and the Student's T test. Surprisingly, having a wider surgical experience overall does not correlate with the best performance at the simulator.

CONCLUSION

The performance of an EVD placement on a simulator correlates with the density of the neurosurgical experience for that specific task performed in the OR, suggesting that simulators are able to differentiate neurosurgeons according to their surgical ability. Namely this suggests that the simulation performance reflects the surgeons' consistency in placing EVDs in the last year.

USim: A New Device and App for Case-Specific, Intraoperative Ultrasound Simulation and Rehearsal in Neurosurgery. A Preliminary Study

BACKGROUND

Intraoperative ultrasound (iUS) is an excellent aid for neurosurgeons to perform better and safer operations thanks to real time, continuous, and high-quality intraoperative visualization.

OBJECTIVE

To develop an innovative training method to teach how to perform iUS in neurosurgery.

METHODS

Patients undergoing surgery for different brain or spine lesions were iUS scanned (before opening the dura) in order to arrange a collection of 3-dimensional, US images; this set of data was matched and paired to preoperatively acquired magnetic resonance images in order to create a library of neurosurgical cases to be studied offline for training and rehearsal purposes. This new iUS training approach was preliminarily tested on 14 European neurosurgery residents, who participated at the 2016 European Association of Neurosurgical Societies Training Course (Sofia, Bulgaria).

RESULTS

USim was developed by Camelot and the Besta NeuroSim Center as a dedicated app that transforms any smartphone into a “virtual US probe,” in order to simulate iUS applied to neurosurgery on a series of anonymized, patient-specific cases of different central nervous system tumors (eg, gliomas, metastases, meningiomas) for education, simulation, and rehearsal purposes. USim proved to be easy to use and allowed residents to quickly learn to handle a US probe and interpret iUS semiotics.

CONCLUSION

USim could help neurosurgeons learn neurosurgical iUS safely. Furthermore, neurosurgeons could simulate many cases, of different brain/spinal cord tumors, that resemble the specific cases they have to operate on. Finally, the library of cases would be continuously updated, upgraded, and made available to neurosurgeons.

Case report: a troublesome ophthalmic artery aneurysm

Objective and Importance When treating large unruptured ophthalmic artery (OA) aneurysms causing progressive blindness, surgical clipping is still the preferred method because aneurysm sac decompression may relieve optic nerve compression. However, endovascular treatment of OA aneurysms has made important progress with the introduction of stents. Although this development is welcomed, it also makes the choice of treatment strategy less straightforward than in the past, with the potential of missteps.

Clinical Presentation A 56-year-old woman presented with a long history of progressive unilateral visual loss and magnetic resonance imaging showing a 20-mm left-sided OA aneurysm.

Intervention Because of her long history of very poor visual acuity, we considered her left eye to be irredeemable and opted for endovascular therapy. The OA aneurysms was treated with stent and coils but continued to grow, threatening the contralateral eye. Because she failed internal carotid artery (ICA) balloon test occlusion, we performed a high-flow extracranial-intracranial bypass with proximal ICA occlusion in the neck. However, aneurysm growth continued due to persistent circulation through reversed blood flow in distal ICA down to the OA and the cavernous portion of the ICA. Due to progressive loss of her right eye vision, we surgically occluded the ICA proximal to the posterior communicating artery and excised the coiled, now giant, OA aneurysm. This improved her right eye vision, but her left eye was permanently blind.

Conclusion This case report illustrates complications of the endovascular and surgical treatment of a large unruptured OA aneurysm.

Treatment of esthesioneuroblastomas

OBJECTIVE

To analyze the clinical features, treatment outcomes, pattern of failures, and course of the disease of a cohort of patients treated for esthesioneuroblastoma (ENB) with craniofacial resection (CFR) at a single institution during a 12-year period.

MATERIAL AND METHODS

Retrospective analysis of 11 patients with ENB treated with CFR in a tertiary care academic medical center from 1998 to 2009.

RESULTS

Median age at diagnosis was 51 years (range 41-67 years). The most common presenting symptom was nasal obstruction (91%). Four patients (36%) presented with Kadish stage B, six patients (55%) with Kadish stage C, and one patient (9%) with Kadish stage D. The initial treatment was craniofacial resection (CFR) alone for three patients (23%), CFR followed by postoperative radiation therapy (RT) in seven patients (64%), while one patient (9%) received both neoadjuvant and adjuvant RT in addition to surgery. The mean and median follow-up times were 66 and 58 months, respectively (range 23-158 months). Seven patients are currently alive with no evidence of disease (64%), while two patients are alive with disease (18%). Overall survival was 100% at one year postoperatively and 80% five years after the primary treatment. The progression free survival was calculated to 73% at one year and 64% at five years.

CONCLUSIONS

ENB is an uncommon diagnosis with an incidence of 0.037/100,000 persons/year in the catchment area of our institution. Treatment can be challenging, especially with advanced disease. CFR with RT offers good oncologic disease control with minimal morbidity.

Craniotomy for brain metastases: a consecutive series of 316 patients

OBJECTIVE

To assess the incidence of craniotomy for brain metastases, overall survival (OS), surgical mortality, and prognostic factors in a large, contemporary, consecutive series from a well-defined catchment area.

MATERIAL AND METHODS

All patients ≥ 18 years who underwent craniotomies for intracranial metastases at Oslo University Hospital, Rikshospitalet and Ullevål, between 2005 and June 30, 2009 were included (n = 316). Patients were identified from our prospectively collected database and a thorough review of all charts to validate the entered data was performed.

RESULTS

The annual incidence of first-time craniotomy for a brain metastasis was 2.6/100,000 inhabitants. Patient age ranged from 25 to 87 years (median 64 years). The 30-day mortality rate was 3.8%. Median OS was 9.2 months. Recursive partitioning analysis was class I in 19.6%, class II in 59.2%, and class III in 21.2% with median OS of 16.2, 8.9, and 5.6 months, respectively (P < 0.001). Lung cancer and melanoma were associated with a higher risk (>1% per year) of developing brain metastases. Significant negative prognostic factors were age ≥ 65, a poor performance score, unstable extracranial disease, presence of extracranial metastases, multiplicity, metastasis in eloquent area, and no post-operative radiotherapy.

CONCLUSIONS

In this population study, the annual incidence of a first-time craniotomy for a brain metastasis was 2.6/100,000, the 30-day mortality rate was 3.8%, and median OS was 9.2 months. The well-known prognostic factors were confirmed.

Executive functions after orbital or lateral prefrontal lesions: neuropsychological profiles and self-reported executive functions in everyday living

OBJECTIVE

This study examined the effects of chronic focal lesions to the lateral prefrontal cortex (LPFC) or orbitofrontal cortex (OFC) on neuropsychological test performance and self-reported executive functioning in everyday living.

METHODS

Fourteen adults with OFC lesions were compared to 10 patients with LPFC injuries and 21 healthy controls. Neuropsychological tests with emphasis on measures of cognitive executive function were administered along with the Behavior Rating Inventory of Executive Functions (BRIEF-A) and a psychiatric screening instrument.

RESULTS

The LPFC group differed from healthy controls on neuropsychological tests of sustained mental effort, response inhibition, working memory and mental switching, while the BRIEF-A provided more clinically important information on deficits in everyday life in the OFC group compared to the LPFC group. Correlations between neuropsychological test results and BRIEF-A were weak, while the BRIEF-A correlated strongly with emotional distress.

CONCLUSIONS

It was demonstrated that LPFC damage is particularly prone to cause cognitive executive deficit, while OFC injury is more strongly associated with self-reported dysexecutive symptoms in everyday living. The study illustrates the challenge of identifying executive deficit in individual patients and the lack of strong anatomical specificity of the currently employed methods. There is a need for an integrative methodological approach where standard testing batteries are supplemented with neuropsychiatric and frontal-specific rating scales.

MGMT promoter methylation in gliomas-assessment by pyrosequencing and quantitative methylation-specific PCR

BACKGROUND

Methylation of the O(6)-methylguanine-DNA methyltransferase (MGMT) gene promoter is a favorable prognostic factor in glioblastoma patients. However, reported methylation frequencies vary significantly partly due to lack of consensus in the choice of analytical method.

METHOD

We examined 35 low- and 99 high-grade gliomas using quantitative methylation specific PCR (qMSP) and pyrosequencing. Gene expression level of MGMT was analyzed by RT-PCR.

RESULTS

When examined by qMSP, 26% of low-grade and 37% of high-grade gliomas were found to be methylated, whereas 97% of low-grade and 55% of high-grade gliomas were found methylated by pyrosequencing. The average MGMT gene expression level was significantly lower in the group of patients with a methylated promoter independent of method used for methylation detection. Primary glioblastoma patients with a methylated MGMT promoter (as evaluated by both methylation detection methods) had approximately 5 months longer median survival compared to patients with an unmethylated promoter (log-rank test; pyrosequencing P = .02, qMSP P = .06). One third of the analyzed samples had conflicting methylation results when comparing the data from the qMSP and pyrosequencing. The overall survival analysis shows that these patients have an intermediate prognosis between the groups with concordant MGMT promoter methylation results when comparing the two methods.

CONCLUSION

In our opinion, MGMT promoter methylation analysis gives sufficient prognostic information to merit its inclusion in the standard management of patients with high-grade gliomas, and in this study pyrosequencing came across as the better analytical method.

Malignant granular cell tumor of the skull base

OBJECTIVE AND IMPORTANCE

Malignant granular cell tumors (MGCTs) are extremely rare, high-grade sarcomas of Schwann cell origin. They often metastasize and are associated with short survival. We describe a patient with a large MGCT arising from the suboccipital nerve that eroded the posterior skull base, invaded the perifocal neck muscles, demonstrated perineural extension, and metastasized to regional lymph nodes.

CLINICAL PRESENTATION

A 60-year-old woman with several years' history of neck pain noticed a right-sided suboccipital swelling 4 months prior to seeking medical attention. Magnetic resonance imaging (MRI) showed a 5-cm bone-eroding suboccipital tumor and a second tumor, anterocaudal to this, 4 cm in diameter.

INTERVENTION

The patient underwent surgery. A 4-cm multinodular tumor was removed, freeing it from the internal jugular vein. A 5-cm suboccipital tumor infiltrated the trapezius, semispinalis capitis, and longissimus capitis muscles. The major and minor rectus capitis muscles were completely engulfed by tumor and their attachments to the occipital bone completely eroded. The oblique capitis muscle was infiltrated at its attachment to the C1 transverse process. These muscles were resected with a free margin to remove all tumor tissue. We then removed tumor encasing the right vertebral artery, the medial mastoid process up to the transverse sinus and anteriorly to the stylomastoid foramen, and lastly, the posterior third of the occipital condyle, achieving a gross total removal and no visible residual on postoperative contrast-enhanced MRI.

CONCLUSION

This case represents the first report of resected primary MGCT involving the posterior fossa and arising from the suboccipital nerve.

Molecular cytogenetic analysis of a gliosarcoma with osseous metaplasia

Gliosarcoma, a rare glioblastoma variant, is composed of a glial and a mesenchymal component. Though the mesenchymal portion most commonly resembles a fibrosarcoma, other differentiation patterns have been observed. We present the first genomic characterisation (karyotyping followed by FISH and array comparative genomic hybridisation analysis) of a gliosarcoma with osseous metaplasia. In addition to chromosomal changes often found in gliomas (+7, -10, -13, and -22), the tumour cells also harboured a hitherto unknown t(3;21)(q13∼21;q21∼22).

Reactive Expansive Intracerebral Process as a Complication of Endovascular Coil Treatment of an Unruptured Intracranial Aneurysm: Case Report

BACKGROUND AND IMPORTANCE:

As a consequence of the increased use of endovascular coiling of intracranial aneurysms, a growing number of case reports on complications are being reported. This article presents a case with a previously undescribed complication of coil treatment: a reactive, noninfectious process after coiling of an unruptured intracranial aneurysm

CLINICAL PRESENTATION:

A 60-year-old hypertensive woman with hypoxic encephalopathy after respiratory arrest following a total thyroidectomy had extensive intentional myoclonus and reduced quality of life as sequelae. An asymptomatic 15-mm internal carotid artery bifurcation aneurysm was discovered on magnetic resonance imaging (MRI) 6 months after the thyroidectomy. After documented growth, the aneurysm was treated endovascularly with bare platinum Guglielmi detachable coils. Three months later, an expansion in the right frontal lobe cranially to the coiled aneurysm was observed. The lesion had grown at the 12-month postcoil MRI and, because of its increasing mass effect, was resected through a craniotomy 2 years after the coiling. As a result of lesion regrowth and cyst formation, she underwent a new craniotomy 5 years later with excision of the now 21-mm large coiled aneurysm, internal carotid artery clip reconstruction, and lesionectomy. Five months postoperatively, the process had not recurred. No signs of malignancy or infection were observed during the histological evaluation of the resected tissue. The tissue is described as a reactive, noninfectious process, most likely resulting from the coils acting as a foreign body.

CONCLUSION:

This article presents a case with a reactive expansive intracerebral process as a complication to endovascular coil treatment of an unruptured intracranial aneurysm.

Overall survival, prognostic factors, and repeated surgery in a consecutive series of 516 patients with glioblastoma multiforme

OBJECTIVES

To study overall survival (OS), prognostic factors, and repeated surgery in glioblastoma multiforme (GBM).

MATERIAL AND METHODS

Retrospective study of 516 consecutive adult patients who underwent primary surgery for a GBM in year 2003-2008.

RESULTS

Median age at primary surgery was 63.7 years (range 18.0-88.0). Median OS was 9.9 months. Age > 60 years, poor preoperative ECOG score, bilateral tumor, biopsy rather than resection, and no temozolomide chemoradiotherapy were negative risk factors. Repeat surgery was performed in 65 patients (13%). Median time between first and second surgery was 7 months. Indications for second surgery were increasing neurological deficits (35.4%), raised ICP (33.8%), asymptomatic but reoperated because of tumor progression verified on MRI (20.0%), and epileptic seizures (11%). Patients who underwent repeated surgery had longer OS; 18.4 months vs 8.6 months (P < 0.001).

CONCLUSIONS

OS for adult GBM patients was 9.9 months. Negative prognostic factors were increasing age, poor neurological function, bilateral tumor involvement, biopsy instead of resection, and RT alone compared to temozolomide chemoradiotherapy. Our rate of repeated surgery for GBM was 13% and the main indications for second surgery were raised ICP and increasing neurological deficits. In a carefully selected group of patients, repeat surgery significantly prolongs OS.

Intracranial tumor surgery in patients >70 years of age: is clinical practice worthwhile or futile?

OBJECTIVES

To study survival and functional outcome after intracranial tumor surgery in elderly patients.

MATERIALS AND METHODS

This is a retrospective study of 289 consecutive patients of age > or =70 years, who underwent primary surgery (resection or biopsy) in the time period 2003-2007 for an intracranial tumor (87 astrocytomas, 79 meningiomas, 62 brain metastases, 33 pituitary adenomas and 28 other tumors).

RESULTS

The surgical mortality was 2.8%. Overall survival at 6 months, 1, 2 and 5 years was 73%, 57%, 46% and 38% respectively. Histology, pre-operative Eastern Cooperative Oncology Group (ECOG) performance score and resection, as opposed to biopsy, were significantly associated with survival. Gender, age and American Association of Anaesthetists (ASA) score were not significantly related to survival. One-year survival after surgery for astrocytoma, meningioma, brain metastases and pituitary adenoma were 24%, 94%, 31% and 96% respectively. More than 85% of the patients who were alive 6 months after surgery had a stable or improved ECOG score compared with their pre-operative score.

CONCLUSIONS

Surgery for intracranial tumors in selected elderly patients is worthwhile, not futile. Age alone should not be used as a selection criterion for treatment.

Histogram analysis of MR imaging-derived cerebral blood volume maps: combined glioma grading and identification of low-grade oligodendroglial subtypes

BACKGROUND AND PURPOSE

Inclusion of oligodendroglial tumors may confound the utility of MR based glioma grading. Our aim was, first, to assess retrospectively whether a histogram-analysis method of MR perfusion images may both grade gliomas and differentiate between low-grade oligodendroglial tumors with or without loss of heterozygosity (LOH) on 1p/19q and, second, to assess retrospectively whether low-grade oligodendroglial subtypes can be identified in a population of patients with high-grade and low-grade astrocytic and oligodendroglial tumors.

MATERIALS AND METHODS

Fifty-two patients (23 women, 29 men; mean age, 52 years; range, 19-78 years) with histologically confirmed gliomas were imaged by using dynamic susceptibility contrast MR imaging at 1.5T. Relative cerebral blood volume (rCBV) maps were created, and 4 neuroradiologists defined the glioma volumes independently. Averaged over the 4 observers, a histogram-analysis method was used to assess the normalized histogram peak height of the glioma rCBV distributions.

RESULTS

Of the 52 patients, 22 had oligodendroglial tumors. The histogram method was able to differentiate high-grade gliomas (HGGs) from low-grade gliomas (LGGs) (Mann-Whitney U test, P < .001) and to identify low-grade oligodendroglial subtypes (P = .009). The corresponding intraclass correlation coefficients were 0.902 and 0.801, respectively. The sensitivity and specificity in terms of differentiating low-grade oligodendroglial tumors without LOH on 1p/19q from the other tumors was 100% (6/6) and 91% (42/46), respectively.

CONCLUSION

With histology as a reference, our results suggest that histogram analysis of MR imaging-derived rCBV maps can differentiate HGGs from LGGs as well as low-grade oligodendroglial subtypes with high interobserver agreement. Also, the method was able to identify low-grade oligodendroglial tumors without LOH on 1p/19q in a population of patients with astrocytic and oligodendroglial tumors.

Growth hormone deficiency in adults: the role of replacement therapy

Although growth hormone has been in clinical use for almost 40 years to promote linear growth in children with growth hormone deficiency, replacement therapy in adults was previously not deemed clinically indicated. However, intensive research over the past decade has led to important advances in our medical knowledge and improvements in the care for patients with growth hormone deficiency. Well-controlled clinical trials have demonstrated beneficial effects of replacement therapy with recombinant human prion-free growth hormone (rhGH; somatropin). The most important restoration parameters include reduction of cardiovascular risk factors and improved lipid profile, normalised body composition, improved exercise capacity and bone mass, as well as enhanced psychological well-being. Some important issues regarding growth hormone deficiency and long term somatropin treatment are unresolved, such as diagnostic criteria and the potential for malignancy and impaired glucose tolerance. Furthermore, the effect on hard end-points such as life expectancy or vertebral fracture rate is unknown, but is expected to emerge from physician-managed, multinational databases. Consequently, at this point somatropin therapy should be given in conjunction with clinical trials.

The effect of short-term temperature changes on superelastic nickel-titanium archwires activated in orthodontic bending

The bending stiffness of superelastic nickel-titanium archwires is influenced by alterations in mouth temperature. The activation and deactivation phases of a load-deflection loop of superelastic wires have different stress-magnitudes. This investigation compared the effect of short-term cooling or heating on the bending force exerted by nickel-titanium archwires. Two rectangular superelastic and one conventional nickel titanium wire were tested in bending at 37 degrees C. The specimens were tested during the activation phase and during the deactivation phase. The wires were kept at constant strain and the bending force was measured continually while the activated specimens were subjected to cold (10 degrees C) or hot (80 degrees C) water. The test situation simulates a patient's archwire that is subjected to cold or hot drinks or food during a meal. The conventional nickel-titanium wire was marginally affected by brief cooling or heating, regardless of activation phase. In contrast, the superelastic wires were strongly affected by short-term application of cold or hot water. When tested in activation phase, the effect of heating was transient whereas the wires continued to exert sub-baseline bending forces after short-term application of cold water. When tested in deactivation phase, the effect of cooling was transient whereas the wires exerted supra-baseline bending forces after a short-term application of hot water. The effect of short-term temperature changes on the bending stiffness of superelastic nickel titanium archwires is dependent upon the bending phase. Cooling induced transient effects on a wire in its deactivation phase, but prolonged effects when the wire was tested in the activation phase. In contrast, the effect of short-term heating was transient when the wire was tested in the activation phase, but prolonged when the wire was tested in the deactivation phase.

[Metotopic craniosynostoses]

BACKGROUND

Premature closure of the metopic suture leads to inhibited growth of the frontal bones, producing a keel-shaped forehead (trigonocephaly). Simple metopic synostosis is usually sporadic. Trigonocephalic patients account for 8-16% of the referrals to craniofacial centers, with a marked male predominance. Intracranial pressure (ICP) may be increased, whereas shunt-dependent hydrocephalus is infrequent. Infrequently, patients have intra- or extracerebral anomalies; one third have varying degrees of neuropsychological problems. The treatment is primarily surgical.

MATERIAL AND METHODS

We present two patients who during infancy developed increasingly keel-shaped foreheads, retruded orbital rims, increased biparietal diameter and close-set eyes (hypothelorism). Both had raised ICP, but normal psychomotoric development. They were operated using radical fronto-orbital surgical remodelling.

RESULTS

Recovery was uneventful. Three months post-operatively, they had pleasing cosmetic results with no symptoms of increased ICP.

INTERPRETATION

Where metopic craniosynostosis is suspected, the infant should be examined clinically with palpation of fontanelles and sutures, evaluated with respect to the shape and development of the facial skeleton, as well as by X-ray of the skull sutures. Radical fronto-orbital surgical remodelling gives a stable correction of the craniofacial deformity and generally a satisfactory cosmetic result.

[Distraction osteogenesis--a new therapeutic principle in complex craniofacial synostosis]

BACKGROUND

Surgical treatment of syndromal craniofacial synostosis consists of combined neurosurgical and maxillofacial reconstructions of the neurocranium and midface. Patients often need several operations if they are to achieve a functionally and cosmetically good result. This is, in part, due to limitations in the amount of "acute" correction possible peroperatively with conventional surgical technique.

MATERIAL AND METHODS

In recent years, a new method called distraction osteogenesis has been developed, by which the skeletal elements are gradually advanced. The method is based upon a process whereby the reparative callus formed between the surfaces of two bone segments is subjected to traction. This leads to new bone formation parallel to the vector of distraction.

RESULTS

Distraction osteogenesis allows for greater mobilizations, hence the promise of fewer reoperations.

INTERPRETATION

The method seems to be a valuable treatment modality in syndromal craniofacial synostosis, where major fronto-orbital, midface or maxillary reconstructions are often called for.

[Frontoethmoidal meningoencephaloceles]

Frontoethmoidal meningoencephalocele is a rare congenital disease where intracranial masses protrudes through a midline defect at foramen coecum from the anterior cranial fossa into the facial skeleton. The patient presents at birth with a soft-tissue swelling at the nasal bridge. In the majority of cases, the cele is completely covered by skin. The face is elongated, the nasal bridge is broad, the upper part of the nose is long, and the patients have telecanthus. Frequently, the patients have a normal psychomotor development, but may have intracerebral malformations and a shunt dependent hydrocephalus. Spinal fluid leakage may result in meningitis. Anosmia is infrequent. The patients may have a wide range of ophthalmological problems. Newborns with meningoencephalocele should be examined by a neurosurgeon. The investigation and work-up commences with a multidisciplinary approach. We present two patients with meningoencephaloceles.

Monobloc and midface distraction osteogenesis in pediatric patients with severe syndromal craniosynostosis

We present 2 children with severe syndromal craniosynostosis who were in need of urgent midface advancement surgery due to recurrent ocular dislocations (Pfeiffer's syndrome type II) or severe upper respiratory obstruction (Crouzon's syndrome). They were operated using distraction osteogenesis, with gradual midface or monobloc advancements. In the Pfeiffer patient, a maxillary distraction of 25 mm achieved effective cessation of ocular dislocations, whereas a 23-mm monobloc advancement in the Crouzon patient achieved cessation of nocturnal arterial desaturations. No major postoperative complications were recorded. Distraction osteogenesis has become a versatile and safe technique that allows for large skeletal advancements.

[Young males have scant knowledge of anatomy and physiology]

When communicating with patients, doctors make assumptions as to their ability to comprehend and adjust the complexity of the information accordingly. We studied the knowledge of anatomy and physiology among young men. 150 men, 18 to 26 years old, serving mandatory military service, were interviewed during doctor consultations. The patients had a minimum of nine years of education; 93% had completed upper secondary school or started education at college level. In order to locate organs and indicate organ size, the patients were asked to draw an outline of the heart, kidneys, liver, spleen, appendix and thyroid gland on a pre-drawn outline of the human body. The patients were also asked to explain the major function(s) of these organs in lay terms. Responses were judged as "correct", "partially correct" and "incorrect" against pre-set criteria. The percentage of correct replies with respect to organ location ranged from 9% (spleen) to 49% (appendix), from 4% (liver) to 53% (appendix) with respect to organ size, and from 0.7% (thyroid gland) to 92% (heart) with respect to organ function. Young men have deficient knowledge of the locations and functions of important internal organs. In addition to correct diagnosis and the start of optimal treatment. consultations should include patient education.

Short-term temperature changes influence the force exerted by superelastic nickel-titanium archwires activated in orthodontic bending

BACKGROUND

Alterations in mouth temperature may lead to changes in the force exerted by an activated superelastic wire. It has been assumed that variations in archwire stiffness associated with short-term cooling or heating are transient. This investigation studied the effect of short-term cooling or heating on the bending force exerted by nickel-titanium archwire.

MATERIAL AND METHODS

Six rectangular superelastic wires and one conventional nickel-titanium wire were tested in bending at 37 degrees C. The test specimens were deflected 0.5 mm, and the bending force was measured continually. The activated specimens were subjected to cold (10 degrees C) or hot (80 degrees C) water under constant deflection, simulating an inserted archwire that is subjected to cold or hot drinks or food during a meal.

RESULTS

The conventional nickel-titanium wire was marginally affected by brief cooling or heating. In contrast, some of the superelastic wires were strongly affected by short-time application of cold or hot water. Whereas the effect of brief heating disappeared quickly, some wires continued to exert sub-baseline bending forces (up to 32% less) after short-time application of cold water and showed little or no tendencies toward increase even after 30 minutes of postexposure restitution (up to 43% less).

CONCLUSIONS

Short-term exposures to hot liquid increased the bending force exerted for a given deflection transiently. The effect of short-term exposures to cold liquid was not always transient; the bending force remained sub-baseline for a number of the thermosensitive wires tested for a prolonged time.

The effect of short-term temperature changes on the mechanical properties of rectangular nickel titanium archwires tested in torsion

Due to their exceptional temperature sensitivity, superelastic nickel titanium wires may be affected by temperature changes associated with ingestion of cold or hot food. It has been assumed that the alterations in archwire stiffness associated with short-term cooling or heating are transient. This investigation studied the effect of these temperature changes on the torsional stiffness of nickel titanium alloys. Eight rectangular superelastic wires were activated to 20 degrees, in longitudinal torsion at body temperature and subjected to cold (10 degrees C) or hot (80 degrees C) water with the strain held constant. The torsional stiffness of some wires was strongly affected. The effect of hot water disappeared quickly, but the wires remained at a level of reduced torsional stiffness (up to 85% less than baseline) after short applications of cold water. The most thermodynamic archwires showed incremental reductions in torsional stiffness when cold water was repeatedly applied. Furthermore, the torsional stiffness remained low (up to 50% less than baseline) and showed no tendency to increase even after 2 hours of post-exposure restitution. It is conceivable that some wires may provide inadequate forces for tooth movement after ingestion of cold liquids.

The effect of temperature on the elastic responses to longitudinal torsion of rectangular nickel titanium archwires

To investigate responses to longitudinal torsion and the effect of temperature on the torsional stiffness of superelastic nickel titanium archwires, eight batches of rectangular wires were tested at 18, 27, 37, and 40 degrees C ambient temperature. The wires were twisted 25 degrees and studied in deactivation. The resulting torque-twist diagrams show that only half the wires had discernible deactivation plateaus at body temperature. The plateaus were generally narrow (1 to 3 degrees) and started at 20 to 23 degrees of torsional twist. The clinical significance of these deactivation plateaus is debatable. Only one wire had a well-defined plateau that was fairly wide (6 degrees) and started at a lower level of twist (17 degrees). The wires without plateaus when deactivated from 25 degrees of twist were retested at body temperature. All exhibited deactivation plateaus subsequent to activating twists of 45 and 60 degrees, and the plateaus became more distinct as the degree of prior activation increased. This indicates that the stress imparted on the alloys by 25 degrees of activating twist is insufficient to induce martensitic transformation at body temperature. As prescriptions advocate bracket pretorque of less than 25 degrees for a maxillary central incisor, the clinical relevance of alloys requiring large activations before they demonstrate deactivation plateaus is questionable. Half the wires tested were markedly influenced by ambient temperature changes; the other half were relatively insensitive to temperature. Responsiveness to thermal stimuli seemed closely related to superelastic tendency.

The effect of cross-sectional dimensional variations of square and rectangular chrome-cobalt archwires on torsion

The purpose of this investigation was to study the control of cross-sectional dimensions and edge bevel by various manufacturers in the production of chrome-cobalt archwires and this effect on transmitting torque through an .018 inc slot bracket system. Twenty-seven different square and rectangular chrome-cobalt wires commonly used in the edgewise technique supplied by five different manufacturers were studied with respect to dimensions, edge bevel, and mechanical properties in torsion. The mechanical study simulated application of torque to an individual tooth. Standard brackets with .018 inch slot heights were used. The results show that variation in cross-sectional dimension and edge bevel leads to variable torsional play (third-order clearance). As an example, .016 x .016 wires have a mean torsional play of as much as 26.8 degrees, with a range of 21.0 to 32.3 degrees. When using .016 x .016 wires, one must apply from 34.8 to 48.6 degrees of twist to get 20 N-mm of torsional moment. This variation is primarily due to the rather wide range in torsional play. As a result, the prediction by which a predetermined torsional moment can be delivered becomes uncertain. The results also show that because the working range in torsion of chrome-cobalt wires is somewhat limited due to high torsional stiffness, precise delivery of torsional moment based on the condition present in the oral cavity is difficult. The torsional stiffness varies between manufacturers within the various dimensional groups as a result of differences in cross-sectional geometry and material properties.

On the variability of cross-sectional dimensions and torsional properties of rectangular nickel-titanium arch wires

Twenty-five rectangular superelastic or conventional work-hardened nickel-titanium alloy wires, commonly used in the 0.018-inch edgewise technique, supplied by seven different manufacturers, along with one braided nickel-titanium and two beta-titanium wires, were studied with respect to wire dimensions, edge bevel, and mechanical properties in longitudinal torsion at 37 degrees C. The wires were twisted 25 degrees and studied in deactivation, simulating application of torque to an individual tooth. Standard Siamese brackets. with stated slot heights of 0.018 inches and measured slot heights of 0.0187 inches, were used. Most wires were within +/-0.0005 inches of the stated dimensions, but had more edge bevel than previously reported for stainless steel and chrome-cobalt alloy wires. Variations in wire dimensions and edge bevel led to variable torsional (third-order) clearance. The torsional stiffness varied among manufacturers within the various wire sizes, this being the result of differences in actual cross-sectional geometry and material properties. None of the tested wires exhibited superelastic properties under the current conditions, and only one wire had a superelastic tendency.

On bracket slot height: a methodologic study

Effective bracket slot height is estimated by using a formula that describes the relationship between bracket slot height, wire dimensions, wire edge bevel, and torsional play (third-order clearance). With a torque measuring instrument, the torsional play was estimated for 10 different brackets (0.018-inch stated slot) of the same manufacturer and type. One arch wire with known dimensions and edge bevel was used for all the measurements. With known torsional play, wire dimensions and edge bevel, the bracket slot height could be calculated. This was performed five times for each bracket and the method error for estimation of torsional play for a single measurement was 0.04 degrees, corresponding to 0.36 mm in slot height. The brackets tested had a mean slot height of 0.476 +/- 0.003 mm, with a range of 0.470 to 0.481 mm (0.0187 +/- 0.0001 inches, range 0.0185 to 0.0189). The variation in bracket slot height was much greater than the method error. The method used to measure bracket slot height seems to have a high degree of accuracy and is easier to implement than conventional methods.

The effect of second-order couple on the application of torque

Complex combinations of linear forces, moments, and couples are developed by the arch wire during orthodontic treatment. For instance, application of torque to a canine during distal driving may create force interactions if the tooth tips distally toward the extraction site. This investigation studied the effect of second-order couples and bracket angulations on the application of torque to a single tooth. By using a test apparatus to simulate application of torque to a single tooth, 0.016 x 0.022 inch stainless steel wires were tested in longitudinal torsion simultaneous to fixed amounts of second-order couples or fixed degrees of second-order bracket angulation. Application of a second-order couple through a bracket to a longitudinally twisted arch wire produces a third-order couple, since the bracket slot walls exert forces on the wire, tending to detwist it. This third-order couple will usually be small as the distance between the two couple members is short. Nevertheless, it may have a restraining effect on the third-order wire-bracket interaction. The results show that application of second-order couples or bracket angulations lead to an increase in exerted torque for angles of twist below 22 degrees. Because of torsional play, a wire twisted 18 degrees in a 0.018-inch bracket slot did not exert any torque unless it was subjected to a second-order couple. Thus, in an in vivo situation where forces interact, the actual torsional play may be substantially less than predicted from theoretical models only regarding third-order mechanics. The restraining effect of second-order couples tapered when the torque created by longitudinal twisting became much larger than the torque exerted by the second-order couple. Second-order couples of biologically acceptable magnitudes had little effect on the level of torque after the third-order clearance had been eliminated.

The effect of friction on the bending stiffness of orthodontic beams: a theoretical and in vitro study

The purpose of this study was to investigate the effect of friction on the bending stiffness of orthodontic beams. A theoretical and experimental model have been established where tensile and compressive forces are applied to an arch wire to simulate the effect of additional friction during activation and deactivation, respectively. The results show that tensile force increases wire stiffness, and that compressive force increases flexibility. Thus more force will be needed during activation and more force will be lost during deactivation. The amount of force lost increases nearly linearly with increasing friction. During activation, the percentage increase in force due to friction for a given deflection is about equal to the loss of force due to friction during deactivation. Friction affects thin flexible wires more than heavy wires. Careful ligation is recommended in the leveling phase to reduce the negative side effects of friction.

On mechanical properties of square and rectangular stainless steel wires tested in torsion

Forty different sizes and types of square and rectangular stainless steel wires, supplied by five different manufacturers, were tested in torsion. The study simulated the situation occurring when torque is applied to an individual tooth. We used standard brackets with 0.018-inch slot heights, with an interbracket distance of 4 mm. The results show that variation in cross-sectional dimension and edge bevel leads to variable torsional play (third-order clearance). As an example 0.016 x 0.022-inch wires have a mean torsional play of as much as 18.5 degrees, with a range of 16.6 degrees to 20.4 degrees. We have shown that when 0.016 x 0.022-inch wires are used, one must apply from 24.6 degrees to 29.2 degrees of twist to get 20 Nmm of torsional moment. This variation is mostly due to a rather wide range in torsional play. As a result, the prediction by which a predetermined torsional moment can be delivered becomes uncertain. The results show that because the working range in torsion of stainless steel wires is somewhat limited, precise delivery of torsional moment, based on the condition present in the oral cavity, is difficult. Torsional stiffness varies considerable within the various dimensional groups, this being the result of variation in cross-sectional geometry and material properties.

[Growth hormone deficiency in adults]

Growth hormone (GH) has been in clinical use for almost 40 years to promote linear growth in growth hormone deficient children. Treatment has usually been stopped after the epiphyseal plates have fused or when the person reaches a proper height. Previously, GH replacement therapy in adults was not deemed clinically indicated. GH-deficiency in adults is now accepted as a clinical entity, manifested by cardiovascular dysfunction, dyslipidemia, reduced capacity for exercise and muscular weakness, altered body composition, increased prevalence of osteoporosis, and impaired psychological well-being. The treatment of adults used to be unrealistic, because of the limited supply of human pituitary-derived GH. Moreover, the risk of transferring Creutzfeldt-Jakobs disease led to a stop in the therapeutic use of pituitary GH preparations. The availability of recombinant human prion-free GH has made replacement therapy possible in GH-deficient adults. In this review, the GH deficiency syndrome in adults is described, together with the results of recent clinical studies of GH replacement treatment in adults.

Growth hormone deficiency in adults: a review

For more than 35 years, growth hormone (GH) has been used to promote linear growth in GH-deficient children. Previously, GH replacement in adults was limited to the supply of human pituitary-derived GH. In addition, until recently, GH replacement was not deemed clinically indicated. With the introduction of recombinant human prion-free GH, replacement therapy in GH-deficient adults has become feasible, and its use has burgeoned. In this review, recent studies on GH therapy in healthy and GH-deficient adults are evaluated to provide a rational basis for the widened scope of its clinical application.

Faecal calprotectin shedding after short-term treatment with non-steroidal anti-inflammatory drugs

BACKGROUND

Increased faecal calprotectin shedding indicates gastrointestinal mucosal inflammation.

METHODS

We studied the effect of short-term treatment with non-steroidal anti-inflammatory drugs (NSAIDs) on faecal calprotectin shedding in two randomized crossover studies, with treatment regimens of indomethacin or naproxen for 14 days in the first study (n = 16) and lornoxicam or naproxen for 7 days in the second study (n = 18).

RESULTS

The method's reproducibility and stability were satisfactory. Indomethacin and naproxen increased the faecal calprotectin significantly from a base line of 4.7 mg/l to 9.0 mg/l and 8.0 mg/l, respectively. Lornoxicam failed to increase the faecal calprotectin. Shedding after 7 days of naproxen treatment was positively correlated to gastroduodenal mucosal inflammation assessed by endoscopy.

CONCLUSIONS

Although seemingly influenced by concurrent upper airway infections, the study indicates that the calprotectin test may be useful for monitoring the inflammatory response to NSAID treatment, even in short-term setting.