Minimally Invasive Approaches in Reoperations after Conventional Craniotomies : Case Series.

Objective: Reoperations are part of neurosurgical practice. In these cases, an already formed craniotomy seems the most logical and appropriate. However, reoperations via large approaches can be quite traumatic for the patient. Then minimally invasive approaches, being less traumatic, can be a good alternative. Methods: We describe 7 consecutive patients who underwent reoperations using minimally invasive approaches in the areas of conventional craniotomies. Surgical Theater® visualization platform was used for preoperative planning. The study evaluated the size of surgical approach, surgical efficacy, and the presence of complications. Results: The size of a minimally invasive craniotomy was significantly smaller than that of a conventional approach. The preoperative goals were achieved in all described cases. There were no complications in the early postoperative period. Although the anatomy of the operated brain region in reoperations is altered, keyhole approaches can be successfully used with the support of preoperative planning and intraoperative neuronavigation. Given that the goals of reoperations may differ from those of the primary surgery, and a large approach is more traumatic for the patient, minimally invasive craniotomy can be considered as a good alternative. The successful use of minimally invasive approaches in areas of conventional craniotomies reinforces the philosophy of keyhole neurosurgery. In cases where goals can be achieved using small approaches, it makes no sense to use large conventional ones. Conclusion: Minimally invasive approaches can be successfully used during reoperations in patients after conventional craniotomies.

Minimally Invasive Approaches in the Surgical Treatment of Intracranial Meningiomas: An Analysis of 54 Cases.

BACKGROUND: Intracranial meningiomas, being a fairly common disease in the population, often require surgical treatment, which, in turn, can completely heal the patient. The localization of meningiomas often influences treatment even if they are asymptomatic. By modernizing approaches to surgical treatment, it is possible to minimize intra- and postoperative risks, while achieving complete removal of the tumor. One of these methods is minimally invasive neurosurgery, the development of which in recent years allows it to compete with standard surgical methods. The purpose of this study was the objectification of minimally invasive approaches, such as the calculation of the craniotomy area and the ratio of craniotomy area to the resected tumor volume. METHODS: The retrospective study consisted of a group of 54 consecutive patients who were operated on in our neurosurgery clinic specialized on minimally invasive neurosurgery. Preoperative planning was carried out using the Surgical Theater visualization platform. Using this system, the tumor volume and craniotomy surface area were calculated. During the analysis, the symptoms before and after the surgery, classification of tumors, postoperative complications, further treatment and follow-up results were assessed. RESULTS: Twelve (22.2%) patients were men and 42 (77.8%) were women. The mean age of the group was 64.2 years (median 67.5). The craniotomy area ranged from 202 to 2,108 mm² (mean 631 mm²). Tumor volume ranged from 0.85 to 110.1 cm3 (mean 21.6 cm3). The craniotomy size of minimally invasive approaches to the skull base was 3-5 times smaller than standard approaches. Skull base meningiomas accounted for 19 cases (35.2%), convexity meningiomas for 26 cases (48.1%), and falx and tentorium meningiomas for 9 cases (16.7%). Three complications were reported: postoperative hemorrhage, CSF leakage, and ophthalmoplegia. Relapse was detected in 2 patients with a mean follow-up of 26.3 months (median 20). CONCLUSION: Minimally invasive approaches in the surgical treatment of intracranial meningiomas reduce the possibility of operating trauma by several times; they are safe and sufficient for complete removal of the tumor.

Multiple intracranial schwannomas of the vestibular and trigeminal nerves: Technical note.

BACKGROUND: A schwannoma is a nerve sheath tumor that is formed by Schwann cells. Vestibular schwannomas are thought to account for the majority of intracranial schwannomas. Non-vestibular schwannomas account for about 10%, about half of which are trigeminal schwannomas. Multiple intracranial schwannomas originating from different cranial nerves are extremely rare. OBSERVATION(S): We describe the clinical case of a 42-year-old female patient with vestibular schwannoma and multiple trigeminal schwannomas. That case shows how multiple trigeminal schwannomas were identified intraoperatively during elective surgery for vestibular schwannoma removal, most of which were resected. No new neurological deficits were observed in the patient. LESSONS: The presence of multiple intracranial schwannomas is extremely rare in neurosurgical practice and can change the intraoperative strategy and the course of the surgery.

Surgical corridor formation by minimally invasive lateral occipital infracortical supra-/transtentorial (OICST) approach in pineal region tumor surgery: A review of 11 cases.

INTRODUCTION: The pineal region is a hard-to-reach part of the brain. There is no unequivocal opinion on the choice of a surgical approach to the pineal region. The surgical approaches described differ in both trajectory (infra- and supratentorial, interhemispheric) and size of craniotomy. They have advantages and disadvantages. The minimally invasive lateral occipital infracortical supra-/transtentorial (OICST) approach we have described has all the advantages of the standard supratentorial approach and minimizes its disadvantages, namely, compression and contusion of the occipital lobe. The minimally invasive craniotomy and small surgical corridor facilitate that. METHODS: We describe 11 consecutive patients with various pineal region tumors (7 cases of pineal cysts, 2 cases of pinealocytoma, 1 case of medulloblastoma, and 1 case of meningioma) who were operated on in our hospital using the lateral OICST approach. Preoperative planning was performed using Surgical Theater®. The surgical corridor was formed using a retractor made from half of a syringe shortened according to the length of the surgical corridor. Preoperative lumbar drain was used. RESULTS: The pineal region tumors were completely resected in all cases. The mean craniotomy size was 2.22 × 1.79 cm. No long-term neurological deficits were reported. CONCLUSIONS: The use of semicircular retractors and intraoperative CSF drainage via a lumbar drain allows to form a small surgical corridor to the pineal region via minimally invasive craniotomy. This reduces traction and traumatization of the occipital lobe, as well as minimizes intra- and postoperative risks.

Fully endoscopic posterior fossa decompression for Chiari malformation type I: illustrative case.

BACKGROUND: Surgery for symptomatic Arnold-Chiari malformation type I involves posterior fossa decompression. There are various approaches, including endoscope-assisted ones. New possibilities and fields of application of fully endoscopic techniques are currently being developed since new and advanced endoscopic equipment and instrumentation are available. OBSERVATIONS: The authors describe the case of a fully endoscopic microsurgical procedure in a 30-year-old female patient with progressive vertigo who was diagnosed with Chiari malformation type I. Neuronavigation and neuromonitoring were used during the surgery. LESSONS: Fully endoscopic surgery can be successfully performed in patients with Chiari malformation I. Intraoperative neuromonitoring and neuronavigation increase safety during this procedure.

Propionibacterium acnes: A Difficult-to-Diagnose Ventriculoperitoneal Shunt Infection. Case Report.

BACKGROUND: Ventriculoperitoneal (VP) shunt infections are a fairly common complication in both the early and late postoperative periods. Sometimes diagnosis is difficult despite the fact that infection is often accompanied by clinical symptoms. Furthermore, pathogenic bacteria can be detected in the cerebrospinal fluid. METHOD: We describe a case of chronic VP shunt infection in a 24-year-old female patient who was operated on for posterior fossa pilocytic astrocytoma and needed a VP shunt. The infection revealed itself 5 years after shunt implantation with nonspecific symptoms, and it took approximately 2 years to make a correct diagnosis. Meanwhile, the patient's condition became critical. The infection was caused by Propionibacterium acnes, which is capable of forming biofilms on implants, and which is difficult to identify due to the peculiarity of its cultivation. RESULT: When the bacterium was identified, the shunt was replaced and antimicrobial therapy was performed, after which the patient's condition improved dramatically and she got back to her normal life. CONCLUSIONS: This case shows how difficult the diagnosis of VP shunt infection can be and what clinical significance it can have for the patient.

Minimally Invasive Dorsal Approach for the Treatment of Giant Presacral Schwannomas.

BACKGROUND: The treatment of giant presacral schwannomas is currently a grand challenge for neurosurgeons. Although these tumors are benign and do not infiltrate the surrounding tissues, it is difficult to choose the best surgical approach because they are surrounded by the pelvic organs and great vessels. There is no universally accepted approach to the surgical treatment because giant presacral schwannomas are rare in the population. The anterior approach through laparotomy is more often recommended in the literature. A dorsal approach that involves laminotomy and stabilization is also described in the literature. However, these approaches are rather traumatic for the patient and have both intraoperative and postoperative risks. OBJECTIVE: To report a minimally invasive dorsal approach for the treatment of giant presacral schwannomas. METHODS: We present a fundamentally new approach to the treatment of these tumors using a minimally invasive dorsal approach, based on the specific anatomy and growth of giant presacral schwannomas. This approach is using the potential of modern neurosurgery. RESULTS: We describe 2 cases of successful total tumor resection using this novel surgical approach. No complications have been registered after the surgery. CONCLUSION: A minimally invasive dorsal approach for the treatment of giant presacral schwannomas is sufficient for complete tumor removal, minimizes intraoperative and postoperative risks, is associated with good cosmetic effect, and can be successfully applied in surgical practice.

The Minimally Invasive Lateral Occipital Infracortical Supra-/Transtentorial Approach in Surgery of Lesions of the Pineal Region: A Possible Alternative to the Standard Approaches.

OBJECTIVE: The pineal region is an anatomical region that is difficult to access surgically, especially when it comes to removing neoplasms. Four main surgical approaches to this region are used as standards nowadays: infratentorial supracerebellar, occipital supra-/transtentorial, interhemispheric, and transventricular approaches. All methods have both advantages and disadvantages and are associated to any extent with intra- and postoperative risks. We have developed a lateral minimally invasive occipital infracortical supra-/transtentorial (OICST) approach, which retains the advantages of the standard occipital transtentorial approach while improving tumor exposure and minimizing its disadvantages. METHODS: We describe 7 consecutive cases of successful complete removals of pineal tumor formations of various quality and size (3 pineal cysts, 2 pineocytomas, 1 meningioma, 1 medulloblastoma) using the OICST approach developed by us. Preoperative 3-dimensional and virtual reality-modeling and the use of a special retractor also contributed to reducing the size of the surgical approach. RESULTS: All patients underwent surgery for removal of a lesion in the pineal region and suffered from no new and permanent neurological deficits postoperatively. The mean size of the craniotomies was 2.3 × 1.85 cm. The minimally invasive approach developed by us carries the advantages of the standard occipital transtentorial approach, but minimizes its disadvantages. The main disadvantage of the standard occipital approach is excessive retraction of the occipital lobe, which is frequently associated with visual neurological deficits. Also, with occipital approach, the Rosenthal vein lying along the surgical corridor is frequently not good visible since the tumor is approached from its tip rather than side which limits the overview of the surgical field and can pose a risk. Damage to this vein can cause infarction of the basal ganglia. By approaching the pineal region from more laterally the size of the craniotomy can significantly be reduced, excessive retraction of the occipital lobe can be avoided and the risk of damage to large deep veins can be minimized. The cosmetic outcome with a small skin incision of only about 3 cm is also a very good side effect of this minimally invasive technique. CONCLUSIONS: The minimally invasive lateral OICST approach described by us can be successfully used in the surgery of pineal neoplasms. Reducing the size of the craniotomy does not limit the possibility of complete removal of tumors of various sizes and tissue consistency, and also minimizes the risks of both intra- and postoperative complications.

Minimally Invasive Dorsal Approach in the Surgery of Giant Thoracic Disk Herniation: Technical Note and Clinical Case Report.

BACKGROUND: Giant thoracic disk herniations are calcified hernias that fill >40% of the spinal canal and result in myelopathy with associated neurologic symptoms. This is a fairly rare abnormality that requires surgical treatment. Currently, there is no unambiguous opinion about the surgical approach to the treatment for this pathology. It is believed that the most effective method is the anterior approach (minithoracotomy or thoracoscopic approach), which reduces the risks of spinal cord injury but is associated with the risks of damage to the lungs, pleura, and major vessels. A giant thoracic disk herniation is also quite large. METHODS: We describe the case of a 60-year-old female patient with a giant thoracic disk herniation. Complete removal of the hernia through a minimally invasive dorsal approach was performed, followed by stabilization. In this case, we used 3-dimensional planning with the help of Surgical Theater, as well as intraoperative neuromonitoring. We also used the ZEISS QEVO, a microinspection tool to aid in resection. RESULTS: No complications have been registered after the surgery. In this case, surgery resulted in a curative treatment outcome for the patient. CONCLUSIONS: The minimally invasive dorsal approach in the surgery of giant thoracic herniated disks can be successfully used in neurosurgical practice. With this approach, it may be possible to avoid dorsal stabilization, but this requires additional research.

Total resection of presacral giant schwannoma via minimally invasive dorsal approach: illustrative case.

BACKGROUND: Giant presacral schwannomas are extremely rare in neurosurgery. There are various approaches to the surgical treatment of symptomatic giant presacral schwannomas. The least traumatic is the one-stage surgery with a dorsal approach. OBSERVATIONS: The authors describe a case of a 52-year-old male with pain in the sacral region and partial urinary dysfunction. A total tumor resection through a minimally invasive dorsal approach was performed, and anatomical and functional preservation of all sacral nerves with no postoperative complications was achieved. LESSONS: The authors have shown the possibility of total tumor resection with a minimally invasive dorsal approach without the development of intra- and postoperative complications. Operative corridors that have been created by a tumor can be used and expanded for a minimally invasive dorsal approach to facilitate resection and minimize tissue disruption.