Safeness and efficacy of 2-µm handheld thulium laser during microsurgical resection of supratentorial and infratentorial meningiomas: Experience of a single center

Aims

We performed a retrospective nonrandomized study to analyze the results of a microsurgery of intracranial meningiomas using 2-μm thulium flexible handheld laser fiber (Revolix jr).

Methods

From February 2014 to December 2021, 75 nonconsecutive patients suffering from intracranial meningiomas, admitted in our department, have been operated on with microsurgical technique assisted by 2-μm thulium flexible handheld laser. We have reviewed demographic and clinical data to evaluate safety and efficacy of the technique.

Results

There were no complications related to the use of the 2-μm thulium laser. We operated on a high percentage of cranial base and tentorial and posterior fossa meningioma in our series. The neurological outcome and degree of resection did not differ from previous series. The neurosurgical team found the laser easy to use and practical for avoiding bleeding and traction.

Conclusion

The use of 2-μm thulium fiber handheld flexible laser in microsurgery of intracranial meningiomas seems to be safe and to facilitate tumor resection, especially in "difficult" conditions (e.g., deep seated, highly vascularized, and hard tumors). Even if in this limited retrospective trial the good functional outcome following conventional microsurgery had not further improved, nor the surgical time was reduced by laser, focusing its use on "difficult" (large and vascularized) cases may lead to different results in the future.

Microsurgical treatment of symptomatic vestibular schwannomas in patients under 40: different results before and after age of 30

In 10-15% of cases of vestibular schwannoma (VS), age at diagnosis is 40 years or less. Little is known about the differences in natural history, surgical findings, and postoperative outcomes of such younger patients as compared to those of greater age. To analyze clinical and surgical and imaging data of a consecutive series of n = 50 patients with unilateral sporadic VS, aged 40 years or younger - separated in a very young group (15-30 years) and a moderately young group (31-40 years). Retrospective case series. Fifty consecutive patients under 40 years of age underwent microsurgical resection of unilateral sporadic VS via the retrosigmoid approach. The study cohort was subdivided into two groups according to the age range: group A, age range 15-30 years (n = 23 patients), and group B, age range 31-40 years (n = 27 patients). The adherence of VS capsule to surrounding nervous structures and the tendency of the tumors to bleed were evaluated by reviewing video records; the course of the FN in relation to the tumor's surface was assessed in each case. Microsurgical removal of tumor was classified as total (T), near total (residual tumor volume < 5%), subtotal (residual tumor volume 5-10%), or partial (residual tumor volume > 10%). Mean tumor size of entire cohort was 2.53 (range: 0.6-5.8) cm: 2.84 cm in group A and 2.36 cm in group B (p = NS). Facial nerve course and position within the cerebellopontine angle did not differ significantly between the two groups. At 6-month follow-up, FN functional outcome was HBI-II in 69.5% in group A, versus 96.3% in group B (p < .001). Hearing preservation was achieved in 60.0% of patients of group A and in 58.3% of group B (p = NS). Total and near-total resection was feasible in 95.6% of cases of group A and in 88.9% of group B (p = NS). Tumor capsule was tightly adherent to nervous structures in 69.6% patients of group A and in 22.2% of group B (p < .05). Significant bleeding was encountered in 56.5% of group A tumors, and in 29.6% of group B tumors (p < .01). Microsurgery of VS in patients aged 40 or less is associated with good functional results, and with high rates of total and near total tumor removal. Patients < 30 years of age have more adherent tumor capsules. Furthermore, their tumors exhibit a tendency to larger sizes, to hypervascularization, to profuse intraoperative bleeding and they present worse long-term functional FN results when compared to patients in their fourth decade of life. Our limited experience seems to suggest that a near total resection in very young VS patients with large tumors should be preferred in adherent and hypervascularized cases, in order to maximize resection and preserve function.

Effect of different solutions in reversing the damage caused by radiotherapy in dentin structure

Background

Previous studies have shown that radiotherapy of the head and neck region can cause direct changes in dental structure. This study evaluated the effect of different solutions on the dentin chemical composition and collagen structure of irradiated dentin.

Material and Methods

Sixty maxillary canines were distributed in 2 groups (n=30): non-irradiated and irradiated (radiotherapy: X-rays of 6 MV in 30 cycles of 2 Gy to 60 Gy). The teeth were sectioned, sanded, and polished to obtain 3x3x2 mm fragments, which were redistributed in 3 subgroups (n=10) according to the treatment employed: chlorhexidine 2% (CL), chitosan 0.2% (QT), and 0.5 M carbodiimide (EDC). The samples were analyzed in FTIR at time zero (T0-control) and after 1 (T1), 3 (T3), and 5 (T5) minutes of immersion in the tested solutions. The data for the areas of the carbonate (C), amide I (AI) bands, and the ratio between the areas of the amide III/proline and hydroxyproline (AIII/PH) bands were analyzed using ANOVA and Tukey test (α=5%).

Results

QT showed lower C values at T1, T3, and T5 (P<0.0001), presenting lower values when compared to CL and EDC subgroups (P<0.05). AI values at T3 and T5 were higher than T0-control and T1, independently of the radiotherapy and dentin treatment factors (P<0.05). At T0-control, the AIII/PH ratio was lower in the irradiated group (P<0.05), whereas the EDC treatment at T1, T3, and T5 and QT at T3 and T5 increased these values (P<0.05), making them similar to non-irradiated subgroups (P>0.05).

Conclusions

Radiotherapy changes the secondary structure of collagen, and EDC was able to restore collagen integrity after 1 minute of immersion, without changing dentin inorganic composition.

Key words:Radiotherapy, collagen, dentin, FTIR, chemical composition.

Effect of carbodiimide and chlorhexidine on the bond strength longevity of resin cement to root dentine after radiation therapy

AIM

To evaluate the effect of carbodiimide (EDC) and chlorhexidine (CHX) on the bond strength (BS) of resin cement to root dentine of teeth submitted to radiotherapy.

METHODOLOGY

One hundred and twenty extracted maxillary canines were selected and assigned to 2 groups (n = 60): nonirradiated and irradiated (30 cycles of 2 Gy, total 60 Gy). Roots lengths were standardized, and canals were prepared and filled. Post spaces were then prepared, and the samples were redistributed according to dentine treatment (n = 20): saline solution (SF); CHX 2%; or EDC 0.5M. After drying the post space, fibreglass posts were cemented. Cross-sectioned slices were obtained, and in half of the specimens of each subgroup (n = 10), the analysis was performed immediately; the others (n = 10) were stored for 10 months before analyses. The most cervical slice of each third was subjected to a push-out test and failure pattern analysis (n = 10), and the most apical slice submitted to the analysis of the adhesive interface by SEM (n = 5). The bond strength data were submitted to anova and Tukey tests, the adhesive interface adaptation was submitted to Kruskal-Wallis and Dunn's tests, and the Chi-square test was used to evaluate the type of failure.

RESULTS

The irradiated specimens had significantly lower bond strength (13.8 ± 4.3) than the nonirradiated (18.1 ± 3.1; P < 0.001). For the irradiated teeth, the bond strengths were significantly lower in the SF and CHX groups (P < 0.001). Also, the bond strengths reduced significantly after 10 months in the SF and CHX groups (P < 0.001). Cohesive failures occurred in dentine for irradiated specimens. Poorer interface adaptation, dentine fractures and microfractures were observed in irradiated specimens, and better adaptation was observed for specimens after EDC treatment.

CONCLUSIONS

Radiotherapy was associated with lower bond strength and worse interface adaptation. Dentine treatment with EDC contributed to adhesive interface longevity during the cementation of glass fibre posts in nonirradiated and irradiated teeth.

Intracanalicular vestibular schwannomas presenting with facial nerve paralysis

BACKGROUND

To describe the surgical management and postoperative course of two patients presenting with facial nerve (FN) paralysis as one of the presenting symptoms of small intracanalicular vestibular schwannomas (VS).

METHODS

Among 153 patients operated for VS since September 2010 to August 2017, two adult female patients presented with rapidly progressive hearing decrease, vestibular symptoms, and FN paralysis (House-Brackmann grades III and IV, respectively). In both cases, c.e. T1-weighted magnetic resonance imaging revealed an enhancing tumor within the internal auditory canal without lateral extension beyond the fundus.

RESULTS

Retrosigmoid approach and excision of tumor showed that the origin of tumor was from the superior vestibular nerve, extrinsic to FN. Gross total tumor resection was obtained, with FN preservation. In the first case, a millimetric fragment of capsule was left because of tight adhesion on FN itself. Histopathology confirmed schwannoma. After surgery, both patients improved FN motor function.

CONCLUSIONS

Although very rarely, VS may start clinically with FN palsy, mimicking FN schwannomas and other less common pathologies. This presentation is exceptional in patients with small intracanalicular VS. Early surgical resection is the only reliable treatment for decompression of nerve, avoiding a complete and not-reversible damage, with possible postoperative FN function improvement or complete recovery.

How I Do It: The Role of Flexible Hand-held 2μ-Thulium Laser Fiber in Microsurgical Removal of Acoustic Neuromas

Aims  We performed a retrospective nonrandomized study to analyze the results of microsurgery of acoustic neuromas (AN) using 2μ-thulium flexible hand-held laser fiber (Revolix jr). Methods  From September 2010 to September 2015, 89 patients suffering from AN have been operated on with microsurgical technique via retrosigmoid approach. In 37 cases, tumor resection was performed with the assistance of 2μ-thulium flexible hand-held laser fiber (L-group). Eight cases operated on with the assistance of CO ₂ hand-held flexible laser fiber were excluded from this study. A total of 44 patients, operated on without laser assistance during the same period, were used as comparison group (C-group) (matched pair technique). Facial nerve function was assessed with the House-Brackmann (HB) scale preoperatively, and 1 week and 6 months postoperatively. Results  Overall time from incision to skin suture changed in relation to size of tumor (165-575 minutes) and was not affected by the use of laser. In 7 out of 81 cases, a preoperative facial nerve palsy HB2 and in 1 case, HB4 (permanent) were observed. In the remaining 80 cases, at 6-month follow-up, facial nerve preservation rate (HB1) was 92.5%. Hearing preservation rate (AAO-HNS A/B classes) was 68.2% (26 out of 36). Adopting a 0 to 3 scale, the mean surgeon satisfaction rate of usefulness of laser fiber was 2.7. Conclusion  The use of 2μ-thulium hand-held flexible laser fiber in AN microsurgery seems to be safe and subjectively facilitates tumor resection especially in "difficult" conditions (e.g., highly vascularized and hard tumors). In this limited retrospective trial, the good functional outcome following conventional microsurgery had not further improved, nor the surgical time reduced by laser. Focusing its use on "difficult" (large and vascularized) cases may lead to different results in future.

High-Dose Radiation-Induced Meningioma in Children

OBJECT

High-dose radiation-induced meningiomas in children are a rare occurrence. We discuss the clinical data and the differences of these rare tumors from those of spontaneous counterpart and radiation-induced meningiomas of the adult population.

CASE REPORT

We report a case of meningothelial meningioma, which occurred in a 9-year-old boy who underwent radiotherapy for a parieto-occipital cutaneous angioma. In addition, we collected 18 cases of high-dose radiation-induced meningiomas in children from a literature review with Medline.

RESULTS

Radiation-induced meningiomas in children show a female predominance, a short latency period that seems to be related to the age at irradiation, and an aggressive behaviour.

CONCLUSION

Exposure to the potentially carcinogenic effects of radiotherapy should be reserved only for tumors that demonstrate subsequent progression. A meticulous follow-up of patients treated with radiation therapy is mandatory.

Surgical treatment of pituitary tumors in the elderly: clinical outcome and long-term follow-up

Pituitary adenomas in the elderly represent an increasing proportion of pituitary tumors, making the surgical management of these patients of special importance. We therefore decided to review our experience with transsphenoidal surgery (TSS) in this age group, in order to better evaluate its efficacy, safety and outcome. A retrospective study was performed on 39 patients aged more than 70 years at the time of surgery (mean age 74.1 +/- 2.9 years) and with a minimum follow-up duration of 4 years at the time of the study. Thirty-one had a nonfunctioning pituitary adenoma, 5 had a GH-secreting adenoma and 3 a macroprolactinoma, respectively. The commonest presenting symptom was visual deterioration (60%), whereas hypopituitarism were present in 41% of patients. All patients underwent TSS without any major peri- and post-operative complications. Visual fields improved in 74% of patients. Post-operative radiotherapy was performed in 17 patients with partial surgical resection and/or persistent hormonal hypersecretion, whereas 22 patients with subtotal or total surgical resection were treated by surgery only. Long-term follow-up (mean 9.1 +/- 2.7 years) showed evidence for tumor regrowth in one irradiated (5.9%) and 3 non-irradiated patients (13.6%), respectively. A noticeable complication of radiotherapy was progressive hypopituitarism, which worsened or developed in 65% of patients. We conclude that TSS is safe and well tolerated even in elderly patients, with a low incidence of minor complications. The indications for post-operative radiotherapy in patients with incomplete tumor resection should be better defined.

Primary leptomeningeal melanomatosis: early leptomeningeal enhancement on MRI

One unusual case of primary leptomeningeal melanomatosis is presented. The patient, 53-year-old male, was admitted to our observation for 1 month history of psychasthenia and amnesia. Despite several polyspecialistic clinical, neuroradiological and cytological examinations, conclusive diagnosis was made only with a biopsy of leptomeningeal nodule. The present case allows as to identify 2 stages in the evolution of primary diffuse leptomeningeal melanomatosis. The initial phase is characterized by slight mental impairment without hydrocephalus; during the later phase there is severe, diffuse neurological impairment and both CT and MRI show hypercaptation of the intracranial leptomeninges and multiple, leptomeningeal tumoral nodules.