Overlapping stimulation of subthalamic nucleus and dentato-rubro-thalamic tract in Parkinson's disease after deep brain stimulation.

BACKGROUND: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) reduces tremor, rigidity, and akinesia. According to the literature, the dentato-rubro-thalamic tract (DRTt) is verified target for DBS in essential tremor; however, its role in the treatment of Parkinson's disease is only vaguely described. The aim of our study was to identify the relationship between symptom alleviation in PD patients and the distance of the DBS electrode electric field (EF) to the DRTt. METHODS: A single-center retrospective analysis of patients (N = 30) with idiopathic Parkinson's disease (PD) who underwent DBS between November 2018 and January 2020 was performed. DRTt and STN were visualized using diffusion-weighted imaging (DWI) and tractography protocol of magnetic resonance (MR). The EF was calculated and compared with STN and course of DRTt. Evaluation of patients before and after surgery was performed with use of UPDRS-III scale. The association between distance from EF to DRTt and clinical outcomes was examined. To confirm the anatomical variation between DRTt and STN observed in tractography, white matter dissection was performed with the Klingler technique on ten human brains. RESULTS: Patients with EF overlapping STN and DRTt benefited from significant motor symptoms improvement. Anatomical findings confirmed the presence of population differences in variability of the DRTt course and were consistent with the DRTt visualized by MR. CONCLUSIONS: DRTt proximity to STN, the main target in PD DBS surgery, confirmed by DWI with tractography protocol of MR combined with proper predefined stimulation parameters may improve efficacy of DBS-STN.

Magnetic resonance spectroscopy in intracranial tumours of glial origin.

BACKGROUND AND PURPOSE: To determine in vivo magnetic resonance spectroscopy (MRS) characteristics of intracranial glial tumours and to assess MRS reliability in glioma grading and discrimination between different histopathological types of tumours. MATERIAL AND METHODS: Analysis of spectra of 26 patients with glioblastomas, 6 with fibrillary astrocytomas, 4 with anaplastic astrocytomas, 2 with pilocytic astrocytoma, 3 with oligodendrogliomas, 3 with anaplastic oligodendrogliomas and 17 control spectra taken from healthy hemispheres. RESULTS: All tumours' metabolite ratios, except for Cho/Cr in fibrillary astrocytomas (p = 0.06), were statistically significantly different from the control. The tumours showed decreased Naa and Cr contents and a high Cho signal. The Lac-Lip signal was high in grade III astrocytomas and glioblastomas. Reports that Cho/Cr ratio increases with glioma's grade whereas Naa/Cr decreases were not confirmed. Anaplastic astrocytomas compared to grade II astrocytomas had a statistically significantly greater mI/Cr ratio (p = 0.02). In pilocytic astrocytomas the Naa/Cr value (2.58 ± 0.39) was greater, whilst the Cho/Naa ratio was lower (2.14 ± 0.64) than in the other astrocytomas. The specific feature of oligodendrogliomas was the presence of glutamate/glutamine peak Glx. However, this peak was absent in two out of three anaplastic oligodendrogliomas. Characteristically, the latter tumours had a high Lac-Lip signal. CONCLUSIONS: MRS in vivo cannot be used as a reliable method for glioma grading. The method is useful in discrimination between WHO grade I and WHO grade II astrocytomas as well as oligodendrogliomas from other gliomas.

Differential diagnosis of intracranial meningiomas based on magnetic resonance spectroscopy.

BACKGROUND AND PURPOSE: To determine in vivo magnetic resonance spectroscopy (MRS) characteristics of intracranial meningiomas and to assess MRS reliability in meningioma grading and discrimination from tumours of similar radiological appearance, such as lymphomas, schwannomas and haemangiopericytomas. MATERIAL AND METHODS: Analysis of spectra of 14 patients with meningiomas, 6 with schwannomas, 2 with lymphomas, 2 with haemangiopericytomas and 17 control spectra taken from healthy hemispheres. RESULTS: All the patients with meningiomas had a high Cho signal (long TE). There were very low signals of Naa and Cr in the spectra of 10 patients. A reversed Ala doublet was seen only in 2 cases. Four patients had a negative Lac signal, whereas 3 had high Lac-Lip spectra. Twelve spectra showed high Cho signals (short TE). In one case the Cho signal was extremely low. All spectra displayed a very low Cr signal, but high Glx and Lac-Lip signals. Ala presence was found only in 3 patients. The mean Cho/Cr ratio (PRESS) was 5.97 (1.12 in normal brain, p < 0.05). Lac-Lip was present in all the meningiomas (STEAM). The Ala signal was seen only in 2 spectra with long TE and in 3 sequences of the short TE sequences. There were both ß/γ-Glx and α-Glx/glutathione signals in all 14 meningiomas. CONCLUSIONS: MRS is unable to discriminate low and high grade meningiomas. The method seems to be helpful in discriminating lymphomas (absent Glx signal), schwannomas (mI signal in the short TE sequences) and haemangiopericytomas (presence of mI band) from meningiomas.

Glioma cells showing IDH1 mutation cannot be propagated in standard cell culture conditions.

BACKGROUND: It has recently been reported by several sources that original (i.e., present in vivo) glioma cell phenotypes or genotypes cannot be maintained in vitro. For example, glioblastoma cell lines presenting EGFR amplification cannot be established. METHODS AND RESULTS: IDH1 sequencing and loss of heterozygosity analysis was performed for 15 surgery samples of astrocytoma and early and late passages of cells derived from those and for 11 archival samples. We were not able to culture tumour cells presenting IDH1 mutations originating from currently proceeded 10 tumours; the same results were observed in 7 samples of archival material. CONCLUSION: The IDH1 mutation is expected to be almost mutually exclusive with EGFR amplification, so glioma cells with IDH1 mutations seem to represent a new group of tumour cells, which cannot be readily analysed in vitro because of their elimination. The reasons for this intriguing phenomenon should be investigated since its understanding can help to define a new therapeutic approach based on simulating in vivo conditions, responsible for tumour cells elimination in vitro. Moreover, a new model for culturing glioma cells in vitro should be designed since the current one does not provide conditions corresponding to in vivo growth.

Magnetic resonance imaging of rare intracranial neoplasms--role of the in vivo 1 h spectroscopy in the radiological differential diagnostics.

BACKGROUND: The object of this study was to evaluate the usefulness of magnetic resonance (MR) spectroscopy in differentiating rare intracranial tumours in adult patients. Review of the literature on results of MR spectroscopy in these lesions is also included. MATERIAL AND METHOD: 89 patients with brain tumours were evaluated preoperatively with in vivo 1.5 T MR spectroscopy (according to eTumour study requirements). 8 of them were diagnosed as having very rare neoplasms: haemangiopericytoma (2), lymphoma (2), plexus papilloma (2), chondroma (1) and purkinjoma (1). Spectra of these tumours were compared to spectra of common brain tumours that could resemble these lesions. RESULTS: MR spectroscopy enabled discrimination between meningiomas and haemangiopericytomas, meningiomas and lymphomas, and purkinjomas or chondromas and other brain tumours. The method was unreliable in distinguishing between glioblastomas and lymphomas. CONCLUSION: The small number of patients made statistical analysis impossible. However, at present, it seems that neuroradiological diagnosis should not rely on MR spectroscopy alone.

BCR expression is decreased in meningiomas showing loss of heterozygosity of 22q within a new minimal deletion region.

Neurofibromin 2 (NF2), located on chromosome arm 22q, has been established as a tumor suppressor gene involved in meningioma pathogenesis. In our study, we investigated 149 meningiomas to determine whether there are additional tumor suppressor genes localized on chromosome 22q, apart from NF2, that might be involved in meningioma pathogenesis. The LOH analysis on chromosome 22q identified two regions of deletion: the first one, which is limited to the NF2 gene locus, and the second one, which is outside this location. The new minimal deletion region (MDR) included the following genes: BCR (breakpoint cluster region), RAB36 (a member of RAS oncogene family), GNAZ [guanine nucleotide binding protein (G protein), alpha-z polypeptide], and RTDR1 (rhabdoid tumor deletion region gene 1). The expression levels of all these genes, including NF2, were subsequently analyzed by quantitative real-time polymerase chain reaction. We observed a significantly lowered expression level of NF2 in meningiomas with 22q loss of heterozygosity (LOH) within NF2 region compared to the one in meningiomas with 22q retention of heterozygosity (ROH, P<0.05). Similarly, BCR showed a significantly lowered expression in meningiomas with 22q LOH within the new MDR compared to cases with 22q ROH (P<0.05). Our data, together with the already published information considering BCR function suggest that BCR can be considered as a candidate tumor suppressor gene localized on chromosome 22q which may be involved in meningioma pathogenesis.

Molecular analysis of chromosome 1, 10 and 19 abnormalities in human oligodendroglial tumors: relationship between frequency of LOH grade, age and gender.

BACKGROUND: Loss of heterozygosity (LOH) on 1p and 19q is observed in most oligodendroglial tumors. LOH on 10q appears to be less common in these tumors as compared to other gliomas. PATIENTS AND METHODS: We reviewed 14 patients with oligodendroglial tumors (10 low-grade and 4 anaplastic oligodendroglioma) to evaluate the frequency of LOH on 1p, 10q and 19q and correlate it with tumor grade and patients' age and gender; 5 loci on 1p and 5 on 19q as well as 4 on 10q were analyzed for LOH using PCR techniques. RESULTS: LOH on 1p together with 19q was detected in 6 tumors, 1 tumor showed deletion of 19q accompanied with deletion on 10q. Deletion on 1p was associated with deletion of 19q (p < 0.005) and mutual associations among deletions at loci on 19q (p < 0.05) were found. Patients with LOH on 1p were younger on average than patients with retained heterozygosity (p = 0.05). Grade II oligodendrogliomas predominated among younger patients (p < 0.01) while grade III oligodendrogliomas predominated among women (p < 0.005). No association between LOH on 1p nor 19q and tumor grade or patients' gender was found. CONCLUSION: Our study provides several clinically interesting findings and further supports the hypothesis of chromosome 1p and 19q involvement in the oligodendroglial cancerogenesis.

[Hyponatremia after subarachnoid hemorrhage caused by ruptured intracranial aneurysm]. / Hiponatremia u chorych po krwotoku podpajeczynówkowym z peknietego tetniaka wewnatrzczaszkowego.

Hyponatremia developed both prior to and after surgery in 30.5% and 23.4% out of 164 patients with ruptured intracranial aneurysms. It was more frequent postoperatively in those patients in whom baseline serum sodium levels were lower. Hyponatremic patients were older than normonatremic. The mean difference in age was about 7 years. The authors, basing on CT scans, have found that hyponatremia development has been more likely in patients with blood visible in subarachnoid space, specially chiasmatic cistern, and patients with ventricular bleeding or hydrocephalus. Hyponatremia following subarachnoid hemorrhage seems to result from the ischemic lesions to hypothalamus i may, therefore, be considered as vegetative equivalent of so-called cerebrovascular spasm.

[Computerized tomography in the diagnosis of hemorrhage caused by ruptured intracranial aneurysm]. / Tomografia komputerowa w rozpoznawaniu krwawienia z peknietego tetniaka wewnatrzczaszkowego.

The authors presented current views on usefulness of computed tomography (CT) for diagnosing the bleeding from a ruptured intracranial aneurysm. CT should be done in every such case, whereas the lumbar puncture remains the diagnostic method of choice, when CT is not available or in those patients in whom CT shows no haemorrhage. Sensitivity of CT decreases with time that elapsed from the stroke; false negative results are the least likely to occur within the first 48 hours after bleeding episode to subarachnoid space.

[Various problems related to the occurrence of hydrocephalus after subarachnoid hemorrhage caused by ruptured cerebral aneurysm]. / Niektóre zagadnienia zwiazane z pojawieniem sie wodoglowia po krwotoku podpajeczynówkowym z peknietego tetniaka naczyn mózgowych.

A CT scan done on admission showed widening of the ventricular system in 56 (34%) out of 164 patients with a ruptured intracranial aneurysm. 82% of the patients were admitted within 5 days after the bleeding. Those with hydrocephalus were often in a poor clinical condition (grades 3-5 Hunt and Hess, p less than 0.01) with up-going plantars twice as frequently encountered as in the remaining group. Widening of the ventricles adversely affected the prognosis. With hydrocephalus rebleeding was more frequent (p less than 0.02) and so was the ischaemic neurological deficit, whereas long-term treatment results were worse (p less than 0.01) with a double mortality rate (p less than 0.02). Hydrocephalus was more frequent in older patients (p less than 0.001 and in those with posterior fossa aneurysms (p less than 0.005). It was also promoted by diffuse and extensive bleeding into the subarachnoid space (p less than 0.01) and by intraventricular haemorrhage (p less than 0.0001). Three patients were treated with ventricular drainage.

[Computerized tomography in aneurysms of the posterior cranial fossa]. / Tomografia komputerowa w tetniakach tylnej jamy czaszkowej.

The authors discuss the clinical usefulness of CT scan in patients with ruptured posterior fossa aneurysms. Among 164 patients after SAH, in 17 the bleeding was caused by aneurysms located in posterior fossa. The exact diagnosis of the bleeding during 5 days after SAH was possible in 94% of the patients, that is similar as in supratentorial aneurysms. The characteristic symptoms of SAH in these aneurysms was the symmetric presence of blood in basal cisterns, intraventricular haemorrhage and, in consequence,--hydrocephalus. Aneurysms of bifurcation of BA were characterized by presence of blood in interpeduncular cistern; this phenomenon was not observed in PICA aneurysms. The aneurysms of BA were more often seen in direct CT-Scan.

[Magnetic stimulation of the human nervous system. Theoretic basis and clinical application]. / Stymulacja magnetyczna ukladu nerwowego u ludzi. Podstawy teoretyczne i zastosowanie kliniczne.

Magnetic stimulation of the nervous system is a new technique introduced in 1985 by Barker, Jalinous and Freeston. Using short pulses of a time-varying magnetic field it allows a noninvasive stimulation of the motor cortex and deeply placed peripheral nerves. The authors presented basic principles and applications of this method. Stimulation procedures were described and the problem of safety and possible side-effects was discussed. Advantages and disadvantages of the method were presented in comparison to electrical stimulation. Preliminary results of the clinical studies conducted chiefly in patients with multiple sclerosis and cervical spondylosis were reviewed.

Pre- and postoperative motor conduction times, measured using magnetic stimulation, in patients with cervical spondylosis.

Motor conduction time (MCT) between head and neck in pathways to abductor digiti minimi was measured pre- and postoperatively in 15 patients. There was a significant improvement in MCTs in patients with myelopathy who improved clinically, but preoperative MCTs provided no clear, predictive information. Magnetic stimulation may be of value in quantifying motor function before and after surgery in patients with cervical spondylosis.

Association of suprasellar meningioma with pituitary adenoma.

An unusual case of an 81-year-old patient with coexisting pituitary adenoma and suprasellar meningioma is reported. The preoperative CT scan failed to demonstrate two separate masses. A short review of the literature is given.

A clinical evaluation of computed tomography in patients with subarachnoid haemorrhage and multiple intracranial aneurysms.

A clinical usefulness of computed tomography was reviewed in 38 consecutive patients with subarachnoid haemorrhage and multiple intracranial aneurysms. CT helped in identification of ruptured aneurysm in more than 70% of cases (it pinpointed source of bleeding in 55% of patients and showed region of haemorrhage in 15% of cases). Its main limitation was inability to detect blood in subarachnoid space (SAS) in patients who were diagnosed later after bleeding (23%). Intracerebral haematoma or localized blood accumulated in SAS showed unequivocally the burst aneurysm. Symmetrical and especially asymmetrical distribution of blood in SAS were also helpful, though the former was misleading in two cases. Moreover, CT detected hypodense lesion of brain in 2 cases, widening of ventricular system in 12 patients and directly visualized aneurysm in 3 cases.

Clinical evaluation of magnetic stimulation in cervical spondylosis.

Conduction in central motor pathways and motor roots was assessed, using the new technique of magnetic stimulation, in 39 patients with cervical spondylosis. Recordings were taken from abductor digiti minimi in all patients and from biceps brachii and abductor hallucis in some. Findings were abnormal ipsilaterally in 27 out of 63 muscles examined in patients with myelopathy, and in 2 out of 38 muscles in patients with radiculopathy. No abnormality was found in 11 muscles examined in patients with negative radiology. There was some correlation between the degree of electrophysiological change and clinical disability. Abnormal conduction was found in some patients with cord compression at the C3/4 or C4/5 interspace but not in a small group with compression at the C5/6 interspace. It seems that magnetic stimulation will provide objective confirmation of upper motor neurone involvement and may provide some measure of its degree, but at present it does not appear to be superior to clinical methods in diagnosing its presence. It may also aid the selection of the correct level for surgical decompression.