Microsurgery of Koos I-II vestibular schwannomas: a case series of 100 consecutive patients

BACKGROUND

Treatment of small vestibular schwannomas (VS) depends on size, growth pattern, age, symptoms, co-morbidities. Watchful waiting, stereotactic radiosurgery and microsurgery are three valid options of treatment.

METHODS

We reviewed clinical sheets, surgical data and results of 100 consecutive patients with Koos Grade I-II VS, operated at our department via a retrosigmoid microsurgical approach between September 2010 and July 2021. Extent of resection was assessed as total, near-total or subtotal. The course of facial nerve (FN) around the tumor was classified as anterior (A), anterior-inferior (AI), anterior-superior (AS) and dorsal (D). FN function was assessed according to House-Brackmann (HB) Scale and hearing level according to AAO-HNS Classification.

RESULTS

Mean tumor size was 1.52 cm. FN course was mainly AS (46.0%) in the overall cohort; in Koos I VS, FN was AS in 83.3%. Postoperative FN function was HB I in 97% and HB II in 3% of cases. Hearing preservation (AAO-HNS class A-B) was possible in 63.2% of procedures. Total/near-total removal was achieved in 98%. Postoperative mortality was zero. Transient complications were observed in 8% of patients; permanent complications never occurred. Tumor remnant progression was observed in one case, 5 years after subtotal removal.

CONCLUSIONS

Microsurgery represents a valid option for management of VS, including Koos I-II grades, with an acceptable complication rate. In particular, in small VS long-term FN facial outcome, HP and total/near-total removal rate are favorable.

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.

Single-Level Cervical Arthroplasty with a Keel-less Prosthesis: Results in a Series of 35 Patients Operated on for Soft Disk Herniation with a Minimum of 3 Years of Follow-Up

BACKGROUND

 Cervical arthroplasty with artificial cervical disks has gained popularity as an alternative to anterior discectomy and fusion. The main advantages of disk arthroplasty include maintenance of the range of movement, restitution of disk height and spinal alignment, and reduction of adjacent segment degeneration (ASD). In this article, we aimed to assess the outcomes of the use of a keel-less prosthesis.

MATERIAL AND METHODS

 We included all the patients who underwent single-level cervical arthroplasties with the Discocerv Cervidisc Evolution for "soft" disk herniation. Clinical assessment included Neck Disability Index (NDI) and visual analog scale (VAS) for neck and arm pain. Radiologic studies investigated the occurrence of ASD and system failure or subsidence. The reoperation rate was also recorded.

RESULTS

 The study included 35 patients (14 men and 21 women; mean age: 42.5 years; mean follow-up: 57.8 months). There was a significant decrease in VAS neck and VAS arm scores, which went from 7.2 and 6.9 preoperatively to 2.2 and 1.7 postoperatively, 2.2 and 1.6 at 6 months, 2.0 and 1.8 at 1 year, and 2.1 and 1.3 at the last follow-up, respectively. The mean NDI score was 58.0 preoperatively, 19.4 postoperatively, 17.0 at 6 months, 16.1 at 1 year, and 16.2 at the last follow-up. Radiologic studies revealed a preserved range of motion in 33 of 35 patients. No ASD occurred and no reoperation was required.

CONCLUSIONS

 Cervical disk arthroplasty with a keel-less prosthesis can be a safe and effective alternative to fusion for degenerative disk disease in selected patients, with a possible reduction of ASD.

Minimally Invasive Microsurgical Removal of Giant Dumbbell Thoracic Neurofibroma: Usefulness of Current Technology for Minimizing the Approach-Illustrative Case and Technical Video

Dumbbell-shaped thoracic tumors usually arise from neurogenic elements within the spinal canal and are characterized by involvement of both spinal canal and posterior thoracic cavity. The tumor mass becomes frequently very large growing inside and outside of the spinal canal, through the connection of the neural foramen, involving the surrounding structures. Most of the dumbbell tumors are peripheral nerve sheath tumors, of which neurofibromas and schwannomas represent the vast majority. Gross total resection is considered the treatment of choice and can be achieved through several combined thoracic-neurosurgical approaches. However, these operations have significant approach-related morbidity; therefore, in the last decades, thanks to the constant progress of technological devices, minimally invasive techniques have been increasingly used for the surgical management of spinal tumors. In this surgical video (Video 1), we present a minimally invasive, single-step posterolateral approach through a small costotransversectomy (centered with echography and fitted with spine navigation) for the surgical management of a giant dumbbell thoracic neurofibroma. The usefulness of current technology guiding the surgical procedure is underlined with special emphasis.

Flexible endoscopic assistance in the surgical management of vestibular schwannomas

Endoscopic-assisted techniques have extensively been applied to vestibular schwannoma (VS) surgery allowing to increase the extent of resection, minimize complications, and preserve facial nerve and auditory functions. In this paper, we retrospectively analyze the effectiveness of flexible endoscope in the endoscopic-assisted retrosigmoid approach for the surgical management of VS of various sizes. The authors conducted a retrospective analysis on 32 patients who underwent combined microscopic and flexible endoscopic resection of VS of various sizes over a period of 16 months. Flexible endoscopic-assisted retrosigmoid approach was performed in all cases, and in 6 cases, flexible and rigid endoscopic control were used in combination to evaluate the differences between the two surgical instruments. The surgical results were additionally compared with a previous case series of 141 patients operated for VS of various sizes without endoscopic assistance. Gross-total resection was achieved in 84% of the cases and near-total resection was accomplished in the rest of them. Excellent or good facial nerve function was observed in all except one case with a preoperative severe facial palsy. Hearing preservation surgery (HPS) was attempted in 11 cases and accomplished in 9 (81.8%). A tumor remnant was endoscopically identified in the fundus of the IAC in all cases (100%). Endoscopic assistance increased the rate of total removal and no intrameatal residual tumor was seen at radiological follow-up. Comparative analysis with a surgical cohort of patients operated with the sole microsurgical technique showed a significative association between endoscopic assistance and intracanalicular extent of resection. Combined microsurgical and flexible endoscopic assistance provides remarkable advantages in the pursuit of maximal safe resection of VS and preservation of facial nerve and auditory functions, minimizing the risk of post-operative complications.

Typical Trigeminal Neuralgia: Comparison of Results between Patients Older and Younger than 65 Years Operated on with Microvascular Decompression by Retrosigmoid Approach

OBJECTIVE

 The incidence of typical trigeminal neuralgia (TN) increases with age, and neurologists and neurosurgeons frequently observe patients with this disorder at age 65 years or older. Microvascular decompression (MVD) of the trigeminal root entry zone in the posterior cranial fossa represents the etiological treatment of typical TN with the highest efficacy and durability of all treatments. This procedure is associated with possible risks (cerebellar hematoma, cranial nerve injury, stroke, and death) not seen with the alternative ablative procedures. Thus the safety of MVD in the elderly remains a topic of discussion. This study was conducted to determine whether MVD is a safe and effective treatment in older patients with TN compared with younger patients.

METHODS

 In this retrospective study, 28 patients older than 65 years (elderly cohort: mean age 70.9 ± 3.6 years) and 38 patients < 65 years (younger cohort: mean age 51.7 ± 6.3 years) underwent MVD via the keyhole retrosigmoid approach for type 1 TN (typical) or type 2a TN (typically chronic) from November 2011 to November 2017. A 75-year-old patient and three nonelderly patients with type 2b TN (atypical) were excluded. Elderly and younger cohorts were compared for outcome and complications.

RESULTS

 At a mean follow-up 26.0 ± 5.5 months, 25 patients of the elderly cohort (89.3%) reported a good outcome without the need for any medication for pain versus 34 (89.5%) of the younger cohort. Twenty-three elderly patients with type 1 TN were compared with 30 younger patients with type 1 TN, and no significant difference in outcomes was found (p > 0.05). Five elderly patients with type 2a TN were compared with eight younger patients with type 2a TN, and no significant difference in outcomes was noted (p > 0.05). There was one case of cerebrospinal fluid leak and one of a cerebellar hematoma, both in the younger cohort. Mortality was zero in both cohorts.

CONCLUSIONS

 On the basis of our experience and the international literature, age itself does not seem to represent a major contraindication of MVD for TN.

Is percutaneous tracheostomy the best method in the management of patients with prolonged mechanical ventilation?

Although percutaneous tracheostomy is a standardized procedure, rare major complications are still being evaluated and discussed. We describe a case of patient, with hemodynamic and respiratory stability, who displayed massive hemorrhage after 16 days of “Ciaglia Blue Rhino” tracheostomy. Unfortunately, neither prompt resuscitation maneuvers nor the surgical approach saved the life of patient.

The open-mouth fronto-orbitotemporozygomatic approach for extensive benign tumors with coexisting splanchnocranial and neurocranial involvement

OBJECTIVE

To describe the advantages of a modification of the standard fronto-orbitotemporozygomatic (FOTZ) approach, consisting of the forced opening of the patient's mouth (open-mouth FOTZ), for the treatment of benign tumors massively involving the splanchnocranium and neurocranium.

METHODS

The modified FOTZ approach obtained by forced mouth opening is described. Such a procedure was introduced with the aim of obtaining a minimally invasive access to lesions involving both the infratemporal-parapharyngeal spaces and the anteromedial cranial fossae. The forced opening of the mouth allows the surgeon to keep the coronoid process of the mandible away from the operating field, producing a wide exposure of the infratemporal space like that of the posterior wall of the maxillary sinus, which can be penetrated from behind without adding destructive procedures on the mandibular bone.

RESULTS

From a series of 45 patients affected by cranial base lesions operated on during an 8-year time period, three patients affected by juvenile nasopharyngeal angiofibromas were selected for an open-mouth FOTZ approach. In all cases, a complete eradication of both the intracranial and extracranial components of the tumor was possible by this approach. The same procedure was then used in four patients affected by extensive meningiomas and two patients harboring Vth cranial nerve schwannomas, with complete tumor removal.

CONCLUSION

In our experience, the open-mouth FOTZ approach seems particularly suited for extensive benign tumors (including juvenile nasopharyngeal angiofibromas) with splanchnocranial and neurocranial involvement. No indication exists for the use of this approach in malignant tumors, in which total eradication with large tumor-free margins is required.