Surgery in Intracerebral Arteriovenous Malformations: The Role of Preoperative Embolization.

AIM: To examine the outcomes of microsurgery only versus combined microsurgery and embolization in treating cerebral arteriovenous malformations (AVM). MATERIAL AND METHODS: A total of 62 patients (34 male and 28 female) with Spetzler-Martin grade 3 (n=44) and grade 4 (n=18) AVMs were examined. Thirty-seven patients were treated with a combination of microsurgery + embolization, whereas 25 patients were treated with microsurgery alone. The clinical characteristics of the treatment groups were compared (ruptured/unruptured, eloquent/non-eloquent, modified Rankin scores, duration of surgery, preoperative and postoperative hemoglobin levels, and use of blood products). RESULTS: The number of patients with ruptured or eloquently localized AVMs was more in combination of microsurgery + embolization. On the other hand, the duration, preoperative versus postoperative hemoglobin levels, and usage of blood products did not differ between treatment groups. CONCLUSION: The results of the study showed no superiority of the combined treatment in managing AVMs in parallel to recent meta-analyses. However, a patient-tailored approach is recommended while making the treatment decision for such challenging intracerebral AVM cases.

The Efficacy of Indocyanine Green Video Angiography During Carotid Endarterectomy: An Institutional Experience.

AIM: To present our experience of 44 consecutive carotid endarterectomy procedures in 42 patients and assess the efficacy and success of ICG-VA in the localization of the plaque sites, extent of the arteriotomy, evaluation of the flow, and presence of thrombus after closure. MATERIAL AND METHODS: This study was retrospectively designed, which included all the patients who underwent carotid stenosis operation between 2015 and 2019. ICG-VA was used in all procedures, and patients with available follow-up and full medical data were analyzed. RESULTS: Forty-two consecutive patients who underwent a total of 44 CEAs were included. The population consisted of 5 (11.9%) female and 37 (88.1%) male patients, all of whom had at least 60% carotid stenosis, as assessed using North American Symptomatic Carotid Endarterectomy Trial stenosis ratios. The mean stenosis rate was 80.55% (range, 60%-90%), the mean patient age was 69.8 years (range, 44-88 years), and the mean follow-up duration was 40 months (range, 2-106 months). In 31 (70.5%) of 44 procedures, ICG-VA revealed the exact location of the obstructive plaque's distal end, and it successfully showed the arteriotomy length, identifying the location of the plaque. ICG-VA correctly evaluated the flow in 38 (86.4%) of 44 procedures. CONCLUSION: Our reported study is cross-sectional, reflecting our experiment using ICG during CEA. ICG-VA can be used as a simple, practical, real-time microscope-integrated technique that can enhance the safety and effectiveness of CEA.

Could Fluorescein Staining in Low-Grade Glial Tumors Guide for Peroperative Differentiation of Pathological Types?

AIM: To define whether characteristics of fluorescein staining help to distinguish low grade gliomas intraoperatively. MATERIAL AND METHODS: We studied 46 patients with supratentorial newly diagnosed noncontrast-enhancing LGGs removed by fluorescence guidance under the YELLOW 560 nm filter. Patients who were treated between July 2019 and 2022 were retrospectively analyzed. Clinical data were collected from patient records. Patients? intraoperative video recordings, pathological examination, and preoperative magnetic resonance imaging (MRI) were analyzed and compared for each patient after the operation. Histopathologically, patients were divided into WHO Grade 2 oligodendrogliomas, diffuse astrocytomas (IDH mutant, 1p19q negative tumors), and pre-glioblastomas (IDH wild type, 1p19q negative tumors). Resection margins were checked using controls contrastenhanced cranial MRI at the postoperative 24 and72 hours. RESULTS: Our observations indicate that fluorescein primarily stains diffuse astrocytomas (IDH mutant, 1p19q negative tumors) and pre-glioblastomas (IDH wild type, 1p19q negative tumors) rather than WHO Grade 2 oligodendrogliomas. CONCLUSION: Fluorescein staining might be an option to determine tumor borders in WHO Grade 2 glial tumors, particularly for those with a higher malignancy potential.

Correlations of Disc Tissue Pathological Changes With Pfirrmann Grade in Patients With Disc Herniation Treated With Microdiscectomy.

BACKGROUND: To reveal whether pathological disc changes (vascularization, inflammation, disc aging and senescence as assessed with immunohistopathological CD34, CD68, brachyury and P53 staining densities respectively) are associated with the extent of disease (Pfirrmann grade) and lumbar radicular pain in patients with lumbar disc herniation. We selectively included a homogenous group of 32 patients (16 males and 16 females) with single-level sequestered discs who had disease stages between Pfirrmann grades I to IV and excluded patients with the complete collapse of the disc space to determine histopathological correlations of the disease more precisely. MATERIALS AND METHODS: Pathological assessments were performed on surgically excised disc specimens stored in a -80°C refrigerator. Preoperative and postoperative pain intensities were determined with visual analog scales (VASs). Pfirrmann disc degeneration grades were determined on routine T2-weighted magnetic resonance imaging (MRI). RESULTS: Stainings were especially observed with CD34 and CD68, which positively correlated with each other and Pfirrmann grading but not with VAS scores or patients' age. Weak nuclear staining with brachyury was observed in 50% of patients and did not correlate with disease features. Focal weak staining with P53 was only seen in the disc specimen of two patients. CONCLUSIONS: In the pathogenesis of disc disease, inflammation may trigger angiogenesis. The subsequent aberrant increase of oxygen perfusion in the disc cartilage may cause further damage, as the disc tissue is adapted to hypoxia. This vicious cycle of inflammation and angiogenesis may be a future innovative therapeutic target for chronic degenerative disc disease.

Transpedicular Corpectomy and Anterior Column Reconstruction for the Treatment of Traumatic Thoracolumbar Fractures.

AIM: To retrospectively analyze the results obtained from the posterior-only approach in non-pathological traumatic thoracolumbar body fractures with spinal cord compression. MATERIAL AND METHODS: A total of 17 patients with traumatic non-pathological thoracolumbar fractures were included in the study. Demographic details include preoperative data such as neurological status, deformity, pain scores, and radiology; intraoperative data such as blood loss, duration of surgery, and complications, and postoperative data including the neurologic status; the duration of hospital stay, pain scores, and deformity correction were analyzed. RESULTS: Among the 17 patients, 8 were in ASIA A, 9 had incomplete neurologic deficits (ASIA C - D), and none was neurologically intact (ASIA E) preoperatively. All patients had TLICS scores > 4 and were treated surgically. The mean TLICS score was 7.31. Although no worsening was detected in the neurological images of the patients during the postoperative period, neurological improvement of at least one ASIA grade was detected in 13 patients. However, it was found that the neurological functions remained the same in the 4 patients. With significant improvement, the mean preoperative VAS score was 8.2, while the mean postoperative VAS score was 3.3. In addition, satisfactory outcomes were obtained in radiological examinations, both in terms of kyphotic deformity and vertebral body collapse. CONCLUSION: Traumatic thoracolumbar fractures can be effectively fixed with the posterior-only approach and the transpedicular route. One of the most significant advantages of this procedure is that peripheral decompression, reduction, anterior column reconstruction, and instrumentation all can be performed simultaneously in the same session.

Evaluation of the Utility of Indocyanine Green Video Angiography in Cerebral Arteriovenous Malformation Surgery.

OBJECTIVE: To assess the utility of intraoperative indocyanine green video angiography (ICG-VA) during microsurgical resection of arteriovenous malformations (AVMs). METHODS: Data of the 24 patients, who were surgically treated for AVM using intraoperative ICG-VA, were reviewed retrospectively. Postoperative digital subtraction angiography (DSA) was performed in all patients before they regained consciousness and became fully awake, and the results were compared with those obtained with intraoperative ICG-VA. A scheduled DSA was performed in all patients in the third, sixth, and 12th postoperative months as well. RESULTS: Authors retrospectively analyzed the records of intraoperative ICG-VA application of all 24 patients. Though the exposures were limited and the image qualities were poor at higher magnification on the surgical microscope within deep surgical fields, the AVM niduses, feeding arteries, draining veins, and their relations to normal vasculature were observed precisely with ICG-VA in all the procedures. Furthermore, the visualization was not qualified enough to identify these pathological vascular structures accurately before evacuating and irrigating the layer of blood clots that obscure the view in patients who presented with hemorrhage. In a patient in our series, a residual nidus in the tail of the caudate nucleus was detected with immediate postoperative DSA which was not revealed by terminal assessment with final intraoperative ICG-VA. CONCLUSIONS: Intraoperative ICG-VA is particularly effective in the identification of the feeder, nidus, and drainer and in the assessment of the flow dynamics of the nidus in cerebral AVM surgery. It may be a quick and safe technique for intraoperative imaging of the angioarchitecture of superficial AVMs, but it may be less helpful for deep-seated lesions. Furthermore, this method alone may not be useful in the identification of residual disease or improvement of the clinical outcomes. DSA has remained the gold standard for confirming AVM obliteration. Despite the technical limitations associated with ICG-VA, a combination of intraoperative ICG-VA and immediate postoperative DSA may advance the safety and efficacy of AVM surgery.

Posterior Reversible Encephalopathy Syndrome Developing after Aggressive Posterior Fossa Tumor Surgery.

Posterior reversible encephalopathy syndrome (PRES) is a rare neurologic disorder, having such common radiological findings as vasogenic edema and white matter changes in watershed areas. The clinic and radiological outcome may not be reversible in 10 to 20% of patients, like in the case of our patient. Here, we discuss the pathogenetic factors that are essential in developing PRES after posterior fossa surgery. A 4-year-old female was admitted to our clinic with a recurrent/residual mass in the posterior fossa. She previously underwent posterior fossa surgery three times (for what was diagnosed as anaplastic astrocytoma through pathohistology) in another center. She was operated thrice in 5 days, and the tumor radically removed. Two days later, after the last surgery, while waking up, our patient developed seizures and altered consciousness. Her neurological condition was severe. Magnetic resonance imaging findings were compatible with those of PRES. Our patient had multiple risk factors for PRES that were as follows: multiple posterior fossa surgeries, anamnesis of chemotherapy and radiotherapy, high-dose steroid use, intracranial pressure changes, and hypertensive attacks due to surgical manipulation. In preventing the development of PRES, we should beware of sudden changes in blood pressure during surgery and meticulously manipulate the brain stem to avoid any disturbance of the central nervous system homeostasis. PRES may transform into real encephalopathy. If the patient has some of these risk factors, PRES would probably develop after surgery.

Morphometric Assesment of the External Anatomy of Fourth Ventricle and Dorsal Brainstem in Fresh Cadavers.

AIM: To investigate the external anatomy of the fourth ventricle and dorsal brainstem using morphometric data, which could be useful for preoperative surgical planning. MATERIAL AND METHODS: Between January 2017 and December 2017, 42 fresh adult cadavers were investigated for the measurements of the cadaver brainstems and fourth ventricle, and they were recorded by photography. Measurements were evaluated according to body mass indexes (BMIs) of the patients. We also investigate the visualization of facial colliculus and stria medullaris on brainstem. RESULTS: A total of 42 fresh cadavers with a mean age of 45.38 ± 16.41 years old were included in this research. We found no statistically significant difference between measurements and BMIs. Facial colliculus was visualized in 92.9% (n=39), but it could not visualized in 7.1% (n=3) of the subjects. When the right side of the stria medullaris was examined, one bundle was seen in 59.5% (n=25) of the subjects, two bundles were seen in 31% (n=13) of the subjects, and 3 bundles were seen in 9.5% (n=4) of the subjects. When the left side of the stria medullaris was examined, one bundle was seen in 57.1% (n=24) of the subjects, two bundles were seen in 33.3% (n=14) of the subjects, and three bundles were seen in 9.5% (n=4) of the subjects. CONCLUSION: Knowledge of the normal morphometry of the dorsal brainstem as it has been reported in this study will help one to assess distortions in any preoperative imaging studies and surgical planning.

Polymorphisms in the Matrix Metalloproteinase-9 Promoters and Susceptibility to Glial Tumors in Turkey.

AIM: Evidence suggests an association between MMP-9 functional gene polymorphisms and several tumors. The aim of this study was to investigate the possible role of single-nucleotide polymorphisms (SNP) at MMP-9 R279Q A/G, P574R G/C and R668Q G/A and R668Q (rs17577) genotypes with glial tumors in Turkey. MATERIAL AND METHODS: The present series consisted of tissue samples obtained from 100 cancer-free controls and 100 patients who had undergone glial tumor resection from 2007 to 2011 at the Cerrahpasa Medical Faculty of Istanbul University. Blood samples were collected to extract the genomic deoxyribonucleic acid (DNA) of each subject by polymerase chain reaction (PCR) and DNA sequencing. The genotypes of MMP-9 P574R, R279Q and R668Q SNPs were determined by using the PCR-RFLP assay. Genotypic distributions between patient and control groups were compared for correlations with glial tumor occurrence. RESULTS: SNPs in MMP-9 were not found to be significantly associated with glial tumor risk among participants except R279Q (G-G) which showed high risk only in multivariate analysis (OR adjusted, 3.15 95% CI, 1.10-9.01). The comparisons between the grade of tumor and the genotypic polymorphisms also showed no significant associations in the case group (all p values > 0.05). CONCLUSION: The current study showed a significant association between the R279Q G/G polymorphism and formation of glial tumor in advanced age. Changed protein features may cause triggering of some subcellular mechanisms that may have a role in activating oncogenic processes over the years. These data add to the growing epidemiological and experimental evidence that MMP-9 may play a role in glial tumors.