Efficiency of interlaminar uniportal endoscopic lumbar discectomy

AIM

Prospective evaluation of the results of endoscopic lumbar discectomy.

METHODS

95 patients were consecutively enrolled in the study between 2017 and 2021. We monitored low back pain and sciatica according to the Visual Analogue Scale (VAS), the limitations in daily activities (Oswestry Disability Index, ODI), overall satisfaction according to a 0-100 % scale, and the rate of surgical complications and reoperations.

RESULTS

Postoperatively, the VAS values of low back pain and sciatica decreased significantly from 5 to 1 point and from 6 to 1 point, respectively, and the pain remained in the tolerable range (VAS 1-2) throughout the follow-up period. The ODI score improved significantly from severe disability (46 %), preoperatively, to moderate disability at discharge and one month after surgery (29 % and 22 %, respectively), down to minimal disability at 3 and 12 months after surgery (12 % and 14 %, respectively). Overall patient satisfaction improved significantly at all follow-up time points (46 %, 70 %, 77 %, 80 %, and 78 %, respectively). Reoperation rate was 6.3 %. Cerebrospinal fluid leakage was observed in one case only (1.1 %). Transient postoperative perianogenital sensory impairment occurred in two patients (2.1 %). There was no evidence of surgical site infection or haematoma.

CONCLUSION

Endoscopic discectomy provides significant pain relief and improves the patient's ability to perform activities of daily living, contributing to greater satisfaction. It is a safe method with a low risk of surgical and neurological complications (Tab. 3, Fig. 3, Ref. 27).

Expression of neuroendocrine markers in meningeal and extrameningeal solitary fibrous tumours - a potential diagnostic pitfall

Solitary fibrous tumours (SFTs) may show unusual morphologies and in such circumstances, unexpected immunoprofile can be misleading. Following an index case of myxoid meningeal SFT with neuroendocrine immunoprofile, we decided to assess a neuroendocrine profile in SFTs from various locations. The cohort of 9 meningeal and 28 extrameningeal SFTs was evaluated for CNS WHO grade (G1-G3) and four tiered Demicco risk stratification. Immunohistochemical detection of synaptophysin, chromogranin, INSM1, CD56, and CD57 was performed in each case and semiquantitatively assessed (0 - no expression; 1+ <10% positive; 2+ 11-50%; 3+ >51%); whole sections (meningeal SFTs) or tissue microarray (extrameningeal SFTs) were used for immunohistochemistry. The cohort included 13 men and 24 females. Meningeal SFTs included 5 WHO G1, 3 WHO G2 and 1 WHO G3 tumours. Extrameningeal SFTs included 21 low-risk, 4 intermediate risk and 2 high risk tumours. INSM1 immunoreactivity was observed in 12/37 cases (32%, 8 cases 1+, 3 cases 2+, 1 case 3+); synaptophysin was positive in 6/35 cases (19%, 5 cases 1+, 1 case 2+); CD56 was positive in 20/37 (54%, 16 cases 1+, 3 cases 2+ and 1 case 3+) and CD57 was expressed in 14/36 cases (39%, 5 cases 1+, 4 cases 2+ and 5 cases 3+). Chromogranin positivity was not observed. No significant association was observed between expression of neuroendocrine markers and tumour grade, Demicco risk group or meningeal and extrameningeal location. Extrapleural SFTs showed tendency for positivity of INSM1 (p=0.014, χ2) and CD57 (p=0.017, χ2), compared to pleural SFTs.

The Need for Emphasis on Intracranial Hypertension Management in Spontaneous Skull Base Meningoencephaloceles

OBJECTIVE

To provide an analysis of patients with spontaneous skull base meningoencephaloceles (MECs) to determine whether definitive surgical treatment requires management of elevated intracranial pressure (ICP).

METHODS

Data of 10 subjects with spontaneous MECs were collected and retrospectively evaluated. Measurement of ICP, prior interventions, treatment with acetazolamide, and characteristics of long-term elevated ICP, among others, were analyzed. Our own indications for cerebrospinal fluid (CSF) diversion and use of postoperative external lumbar drain were analyzed as well.

RESULTS

The sphenoid region was the most common location of MECs. CSF leak was diagnosed in all subjects. The most common graphical signs of elevated ICP were empty sella and arachnoid pits, both of which were present in 90% of cases. Lumbar puncture with opening pressure measurement was performed in 7 patients. Ventriculoperitoneal shunt insertion was indicated in 4 cases before skull base repair and in 2 cases after skull base repair. Two postoperative CSF leaks were managed with external lumbar drain and subsequent shunt installation.

CONCLUSIONS

Spontaneous MECs are often associated with CSF leak. ICP assessment should be a standard of care to ensure successful operative repair of MECs. Insertion of a CSF diversion device must be considered where direct or indirect signs of intracranial hypertension are present.

The effect of free glycerol intake on cerebral glycerol concentration

OBJECTIVE

Cerebral microdialysis (CMD) is a method used to measure the concentration of metabolites and glycerol in the interstitium of the brain. The aim of this study was to investigate the effect of parenterally applied medication and nutrition containing external free glycerol (EFG) on cerebral values of glycerol in patients monitored and treated for non-traumatic subarachnoid hemorrhage (SAH).

METHODS

In 13 patients, the values of CG concentrations were measured using CMD. The amounts of parenterally applied EFG (in hourly intervals) were calculated from patient records. All data were gathered retrospectively. To analyze the association between the parameters of interest and their relationship, Spearman´s correlation and p-values were calculated.

RESULTS

There was no evident relationship between the CG and EFG concentrations when the dataset was analyzed as a whole (r = -0.146). However, when the analysis was applied to single patients, a varying degree of correlations was discovered in 7 patients (r = 0.431-0.867).

CONCLUSION

The possible effect of externally administered glycerol contained in pharmaceuticals and nutrition on its brain concentrations must be considered when interpreting data of CMD (Tab. 2, Fig. 4,Ref. 16) Keywords: glycerol, microdialysis, brain, subarachnoid hemorrhage.

Medically induced CSF rhinorrhea following treatment of macroprolactinoma: case series and literature review

PURPOSE

Although several reports have addressed cerebrospinal fluid (CSF) rhinorrhea following dopamine agonist (DA) therapy of macroprolactinomas, further study is warranted for this relatively uncommon entity. Toward this aim, our retrospective series and review of literature further clarifies recommendations in treatment of this rare problem.

METHODS

We retrospectively reviewed all macroprolactinoma cases in our hospital for a 15-year period. Our systematic search of PubMed identified original articles and reviews of all macroprolactinoma cases with an associated medication-induced CSF leak.

RESULTS

Five patients with drug-induced CSF leak were identified; four of these patients received cabergoline therapy an average of 6 weeks before the onset of rhinorrhea and then underwent surgical repair of the CSF leak. Of 35 published studies included, we identified 60 patients with medication-induced CSF leak. Medical therapy included bromocriptine in 34 patients, cabergoline in 21 patients, and use of both DAs in two patients. Three cases did include complete diagnostic and treatment data. Median time from initiation of the DA treatment to occurrence of rhinorrhea was 6 weeks. For CSF rhinorrhea, 49 patients underwent surgical repair (38 by the transnasal approach) and seven patients were treated nonoperatively.

CONCLUSION

Baseline skull base erosion in macroprolactinomas in combination with subsequent tumor shrinkage induced by DA therapy may result in spontaneous CSF rhinorrhea. Therefore, such patients should be advised about and monitored for this potential setback. Once CSF leak is diagnosed, prompt treatment must be carried out to avoid infectious complications. Transnasal surgery appears the most effective therapeutic approach.

Correction to: Multidisciplinary approach in the treatment of spinal dural arteriovenous fistula-results of endovascular and surgical treatment

The author J. Adamkov was incorrectly captured in the original article and is now corrected in this article.

The relationship between intracranial pressure and lactate/pyruvate ratio in patients with subarachnoid haemorrhage

AIM

The aim of this study was to analyse the relationship between intracranial pressure (intracranial pressure monitoring) and lactate pyruvate ratio (cerebral microdialysis) in patients with ruptured intracranial aneurysms.

METHODS

In a group of fifteen patients, intracranial pressure and lactate/pyruvate ratios were measured and logged in hourly intervals. The relationship between these two variables was subsequently analysed in two ways. 1) Intracranial hypertension (ICP > 20 mmHg) in the presence of energy deprivation (L/P ratio > 30) was noted. 2) The dynamics of L/P ratio changes in relation to immediate ICP and CPP values was analysed.

RESULTS

Out of a total of 1873 monitored hours we were able to record lactate/pyruvate ratios higher than 30 in 832 hours (44 %). Of those 832 hours during which lactate/pyruvate ratios were higher than 30, ICP was higher than 20 in 193 hours (23 %). Out of 219 hours of monitoring, in which ICP was higher than 20, a simultaneously increased L/P ratio higher than 30 was recorded in 193 hours (88 %). L/P ratio values above 30 were associated with decreased CPP values (p = 0.04), but not with increased ICP values (p = 0.79).

CONCLUSION

Intracranial hypertension coincides with energetic imbalance in approximately one quarter of cases. This points to the shortcomings of the most common form of neuromonitoring in SAH patients - ICP monitoring. This method may not be reliable enough in detecting hypoxic damage, which is the major cause of morbidity and mortality in SAH patients (Fig. 5, Ref. 11).

Medial and Superior Orbital Decompression: Improving Access for Endonasal Endoscopic Frontal Sinus Surgery

OBJECTIVE

Visualization by Draf I-III endoscopic access to the frontal sinus via drainage pathways is sometimes inadequate. We compare lateral frontal sinus exposures by Draf approaches versus our modification of removing the medial-superior wall of the orbit while preserving the periorbita.

METHODS

Twenty cadaveric heads dissected using Draf IIB, III, and modified Draf III with medial and superior orbital decompression (MSOD) underwent thin-cut computed tomography (CT) scanning. Under image guidance, measurements extended from the midline crista gali to the most lateral point of the frontal sinus. A case report shows the modified Draf III improved frontal sinus access.

RESULTS

Comparing Draf IIB and III with Draf III with MSOD, respectively, distances between midline and most lateral point averaged 19.1 mm, 23.7 mm, and 30.4 mm (left) and 18.7 mm, 25.1 mm, and 32.2 mm (right). Differences between Draf III with/without MSOD were 6.65 mm (left) and 7.09 mm (right); 12 heads were excluded because of under-pneumatization of the sinuses.

CONCLUSIONS

Draf III with MSOD extended surgical access to lateral regions of the frontal sinus. This extension achieved better visualization and instrumentation with minimal removal of the frontal bone's orbital segment anterior and superior to the anterior ethmoidal artery while preserving the periorbita.

Endoscopic, endonasal variability in the anatomy of the internal carotid artery

BACKGROUND

Classic three-dimensional schemas of the internal carotid artery (ICA) for transcranial approaches do not necessarily apply to two-dimensional endoscopic views. Modifying an existing ICA segment classification, we define endoscopic orientation for the lacerum (C3) to clinoid (C5) segments through an endonasal approach.

METHODS

In 20 cadaveric heads, we classified endoscopic appearance based on shape and angulation of C3 to C5 segments. Distances were measured between both arteries, and between the ICA and pituitary gland.

RESULTS

We identified 4 common ICA patterns: types I through III matched side-to-side, whereas type IV was asymmetric. In 80% of specimens, the pituitary gland had direct contact with the ICA. In 20% of specimens, a space existed between the pituitary gland and the cavernous segment. Access to the posterior aspect of the cavernous sinus medial to the cavernous segment was possible without retraction of the artery or pituitary gland. Spaces between the lacerum and cavernous segments were trapezoid (80%) and hourglass (20%).

CONCLUSIONS

Distinguishing which ICA type courses between the lacerum and clinoid segments can help clarify the relationships between the artery and its surrounding structures during endoscopic approaches. Adapting the classic terminology of ICA segments provided consistency of endoscopic relevance, defined potential endoscopic corridors, and highlighted the critical step of arterial contact.

[The impact of early cranioplasty on cerebral blood flow and its correlation with neurological and cognitive outcome. Prospective multi-centre study on 24 patients]

INTRODUCTION

Cranioplasty after decompressive craniectomy in patients suffering from severe head injury often leads to a functional improvement although, to date, the pathophysiology of this phenomenon remains unclear. A few hypotheses have been proposed. The impact of cranioplasty on cerebral perfusion could be one explanation. We have evaluated the impact of cranioplasty on the functional status of patients undergoing decompressive craniectomy for severe head injury with its influence on cerebral perfusion.

MATERIALS AND METHODS

Twenty-four patients undergoing craniectomy for severe head injury were included in this multi-centric and prospective study. All of them had a cranioplasty within 12 weeks following decompressive craniectomy. A clinical and radiological evaluation was performed prior to and after cranioplasty. Neurological and cognitive evaluation was performed with the Glasgow Outcome Score (GOS), the Frontal Assessment Battery (FAB) and the Mini Mental State Examination (MMSE). Radiological evaluation was performed by perfusion CT scan and transcranial Doppler.

RESULTS

A statistically significant neurological and cognitive improvement was observed in 92% of patients at 6 months follow-up (F-U). Brain perfusion was improved at 6 weeks F-U, predominantly in the affected hemisphere. Systolic and diastolic blood velocity flow were improved in both middle cerebral arteries.

CONCLUSION

Cranioplasty after decompressive craniectomy for patients suffering from severe head injury probably improves the functional outcome of these patients, thanks to a global improvement of cerebral perfusion.