The evaluation of the usefulness of CO2 laser in microsurgical resection of brain tumors

Background:

Since its introduction to surgery, the CO₂ laser has been used in the treatment of various neurosurgical pathologies as it combines cutting, vaporizing, and coagulating properties in one tool and has a safe penetration depth. In this case series of 29 patients, we present the evaluation of the usefulness of the closed system type – sealed tube surgical CO₂ laser in the surgical removal of brain tumors.

Methods:

The Sharplan 40C model SurgiTouch, sealed tube type CO₂ laser, was used in the resection of 29 brain tumors; 13 meningiomas, six metastases, nine gliomas, and one acoustic neuroma. The same senior surgeon (BT) assessed and classified the benefit provided by the CO₂ laser in the resection of the neoplasms to considerable (Group 1), moderate (Group 2), and poor (Group 3).

Results:

Group 1 included 14 patients with 13 meningiomas and one acoustic neuroma, Group 2 included six patients, all of whom had metastases, and Group 3 included nine patients of which six had glioblastoma and three astrocytoma. No complications or technical problems occurred due to the use of the CO₂ laser.

Conclusion:

The CO₂ laser is a valuable complementary tool in brain tumor surgery displaying high efficacy and practicality in the resection of neoplasms which are fibrous and have hard consistency. It has high acquisition and maintenance cost and cannot replace the bipolar diathermy. The newest generation of flexible CO₂ laser fiber provides more ergonomy and promises new perspectives of its neurosurgical use in the modern era.

Volumetric data of normal nucleus accumbens from magnetic resonance imaging scans

Backgrounds and aims. The nucleus accumbens (AcN) belongs to the ventral striatum and it is involved in several neuropsychiatric disorders. In contrast to other subcortical structures, the number of morphometric studies that concern the healthy nucleus is limited. This study aims to investigate the normal volumetric data of the AcN as derived from a large number of manually segmented magnetic resonance imaging (MRI) scans. Methods. The measurements were performed in 106 MRI scans of healthy adults. The resulting volumes have been analyzed for differences related to hemisphere, sex and age. Results. The mean AcN volume was estimated at 473.3 mm3 (SD=±106.8). A slight interhemispheric difference in favor of the left side was found, the value of which was, however, within the limits of the method error. There were no sexual dimorphism signs concerning both the raw and the normalized volumes. A negative correlation between volumes and age was observed only in males. Conclusions. The study provides normal volumetric data of the AcN, useful in the conduct of comparative imaging and post-mortem studies in pathological conditions

Magnetic Resonance Imaging patterns in central nervous system lymphomas: A pictorial review

Five distinctive Magnetic Resonance Imaging (MRI) patterns of Central Nervous System Lymphomas (CNSL) are introduced in this pictorial essay - in an attempt to differentiate lymphoma from other abnormalities with similar MRI appearance, - namely a. solitary supratentorial, b. multiple supratentorial, c. infratentorial, d. intravascular, and e. extraparencymal. Recognition of a specific imaging pattern on brain MR imaging, may facilitate the early diagnosis and prompt treatment initiation, thus improving prognosis of brain lymphoma.

The Use of Real-Time 3D Intraoperative Ultrasound "Angiography" in Localization and Occlusion Control of a Ruptured Mycotic Aneurysm: A Case Report

BACKGROUND

 Infectious (mycotic) aneurysms are rare with high mortality and are most commonly found at the distal branches of the middle cerebral artery (MCA). Because aneurysms of the distal MCA are located deep in the Sylvian fissure and are small in size, intraoperative identification and safe clip occlusion of these aneurysms are challenging. Thus, the use of intraoperative imaging and navigation can be beneficial. We describe the use of intraoperative real-time 3D ultrasound "angiography" (3D-iUS) in localizing and occlusion control of a ruptured MCA M3 segment mycotic aneurysm. To our knowledge, its application in the surgery of a ruptured mycotic distal MCA aneurysm is not yet reported.

CLINICAL PRESENTATION

 A 54-year-old woman with a history of septic thrombophlebitis treated with long-term antibiotic therapy presented with sudden onset of headaches, dysphasia, and seizures. Computed tomography (CT) revealed subarachnoid hemorrhage in the distal portion of the left Sylvian fissure. Digital subtraction angiography (DSA) showed an aneurysm at the peripheral branch of the M3 segment of the MCA with characteristics of an infectious aneurysm. A microsurgical treatment was decided. 3D-iUS scan showed an aneurysm within the Sylvian fissure at a depth of 5 cm. The aneurysm was clipped and a repeated 3D-iUS scan showed total occlusion of the aneurysm and patency of the parent artery. The intraoperative findings were confirmed with a postoperative DSA.

CONCLUSION

 Our case report shows that real-time 3D-iUS, despite its limitations, is an important tool to locate and ascertain the successful clip occlusion of an aneurysm, especially when intraoperative angiography (IA) and indocyanine green (ICG) videoangiography are not available due to low-income settings.

Clipping of a basilar tip aneurysm using hypothermia and circulatory arrest: a case report

Treatment of complex and giant aneurysms remains challenging despite modern endovascular and microsurgical techniques. We report the first case of microsurgical clipping of a complex basilar tip aneurysm under circulatory arrest and hypothermia performed in Greece. A 52-year-old patient presented with a Hunt and Hess Grade 4 subarachnoid hemorrhage. The digital subtraction angiography revealed a complex basilar tip aneurysm. Due to aneurysm complexity, we decided for microsurgical clipping under hypothermia and circulatory arrest. We performed a right pterional craniotomy with orbitozygomatic osteotomy. The patient was then put on heart–lung-machine. Following hypothermia and circulatory arrest, the aneurysm was clipped with its complete occlusion. The patient was discharged with no neurological deficits. Clipping of complex aneurysms under hypothermia and cardiac arrest performed by experienced team is a safe alternative when endovascular therapy or bypass technique is not feasible.

Magnetoencephalography and normal pressure hydrocephalus: A case report

A 82-year-old male experiencing headaches, dementia, urinary incontinence and gait instability was diagnosed with normal pressure hydrocephalus (NPH) and underwent a resting state magnetoencephalography (MEG) examination. MEG data were recorded in a magnetically shielded room with a whole-head 122 channel biomagnetometer. Following MEG, a ventriculoperitoneal (VP) shunt was placed in his head and greatly improved his symptomatology. Spontaneous MEG recordings revealed lower magnetic fields at frontal and frontotemporal regions compared to central and posterior regions. This finding correlated well with the significant ventricular distention, and specifically the enlargement of the frontal horns of the lateral ventricles, observed in presurgical CT. The regional pattern of MEG signal decrease in NPH seems to be quite different from that encountered in brain atrophy. In the latter case, a more generalized distribution of low magnetic fields is observed, possibly reflecting the high sensitivity of MEG to activity originating in sulci. Acquired data suggest that MEG may be able to differentiate between NPH and brain atrophy. Furthermore, MEG could potentially constitute a non-invasive, non-imaging tool, useful in the selection of patients with NPH to undergo shunt surgery. The findings of this study warrant further research in patient groups before firm conclusions can be drawn.

Regenerated Nerve Defects with a Nerve Conduit Containing Dental Pulp Stem Cells in Pigs: An Immunohistochemical and Electrophysiological Evaluation

BACKGROUND

Dental pulp stem cells (DPSCs) present an exciting new tool in the field of peripheral nerve regeneration due to their close embryonic origin. In this study, we examined their potential in pigs, using biodegradable collagen conduits filled with DPSCs. To our knowledge, this is the first time DPCSs are tested for peripheral nerve regeneration in such large animal model.

MATERIALS AND METHODS

The second lateral incisor was extracted from every animal's lower jaw and stem cells were isolated and cultured. The collagen nerve conduits containing the DPSCs were subsequently transplanted into the transected fifth and sixth intercostal nerves, while the seventh intercostal nerve was used as a control and no stem cells were added on the respective collagen conduit.

RESULTS

A histological examination was performed on the 3rd and 6th postoperative months and showed the gradual development of neural tissue and immunohistochemical expression of neuron-specific enolase. An electrophysiological study was performed on the 6th postoperative month and showed similar potentials between the stem cell infusion region (5 ± 0.04 units) and their proximal stumps (5 ± 0.05 units) and slightly smaller potentials in the respective distal stumps (4 ± 0.045 units).

CONCLUSION

The nerves where DPSCs were injected exhibited morphological and functional recovery, in contrast to the control nerves where no recovery was detected; thus, there is a first evidence of the therapeutic potential of DPSCs in peripheral nerve regeneration.

Spinal epidural abscess in a young girl without risk factors

Spinal epidural abscess (SEA) is a rare infection associated with well-established risk factors mainly in adults. We describe an 11-year-old girl without any known risk factors who presented with fever and localized spinal tenderness in the lumbar area and was diagnosed with spinal MRI as suffering from a posterior SEA extending between T11 and L4. She was successfully managed with sequential intravenous and oral antibiotics along with minimally invasive surgery without laminectomy. Methicillin-sensitive Staphylococcus aureus was the responsible pathogen isolated at surgery. Immediate institution of antibiotics, spinal MRI, and well-timed neurosurgical consultation are mandatory for a favorable outcome in cases of SEA in children.

Subclavian steal syndrome secondary to Takayasu arteritis in a young female Caucasian patient

Subclavian steal syndrome (SSS) is most frequently described in Caucasians aged over 50 years because of increased incidence of atherosclerosis in this population. Non-atherosclerotic etiologies of SSS are rare in Caucasians. We present a case of Subclavian Steal Syndrome secondary to Takayasu Arteritis (TA) in a 26 year-old female Caucasian patient. The present case underscores that despite the very low incidence of TA in Caucasians (0.8/1,000,000), this large-vessel vasculitis of unknown etiology should always be considered in the differential diagnosis of subclavian steal syndrome in Caucasian women aged less than 40 years.

Incidence and Case Fatality of Subarachnoid Haemorrhage in Northern Greece: The Evros Registry of Subarachnoid Haemorrhage

Background

Epidemiological data on subarachnoid haemorrhage incidence and case-fatality rates are scarce in the southeastern Mediterranean region. We conducted a population-based study in Evros Province, located in north-eastern Greece, to determine subarachnoid haemorrhage incidence over a 5-year period (2001–2005).

Methods

Evros Province has a well-defined, largely homogeneous population with healthcare organised around a single tertiary-care University Hospital. We organised a prospective computerised registry of permanent Evros residents admitted or transferred to our hospital with a diagnosis of subarachnoid haemorrhage. Standard World Health Organization definitions and overlapping case-finding methods were used to identify all cases of first ever in a lifetime subarachnoid haemorrhage in all age groups, occurring during the study period. The diagnosis was confirmed by computed tomography scan in all hospitalised cases. Sudden deaths attributable to subarachnoid haemorrhage were systematically recorded province-wide by our forensic department and are included in the study.

Results

During the 5-year period, 51 cases of subarachnoid haemorrhage were recorded (28 men, 23 women; mean age 59 ± 17 years). The crude annual incidence rates were 8·3/100000 persons (95% confidence interval: 5·5–12·0) for men, 7·5/100000 (4·8–11·3) for women and 7·9/100000 (5§9–10§4) for all subjects. The standardised incidence rates for groups aged 45–84 years in the European population were 9·3/100000 (5·8–12·8) for men, 6·5/100000 (3·7–9·4) for women and 7·9/100000 (5·7–10·2). The 28-day case-fatality rates for men, women and all subjects were 36% (21–54%), 35% (19–55%) and 35% (24–49%), respectively.

Conclusions

The incidence and case-fatality rate of subarachnoid haemorrhage haemorrhage in Greece appear to be similar to other developed countries. No gender differences in subarachnoid haemorrhage incidence and case-fatality rate were documented.

A pair of clamps for a safe removing and repositioning of beta and gamma angular settings of Brown-Roberts-Wells stereotactic system during operation

The Brown-Roberts-Wells arc system is a non-target-centered design, i.e., without an independent approach angle. The approach angle of this system strictly depends on precalculated values (entry and target point). Therefore, some components of the system used sometimes prevent a direct insight into the operation field. Once the entry point has been set, the arc system normally has to be taken off to permit an unimpeded approach to the burr hole. To facilitate rotation and return to the primary beta and gamma angular settings during stereotactic craniotomy and other surgery, a pair of clamps was designed for the BRW arc system. These clamps help the approach to the entry point in such a way that some components of the arc (e.g., the guide block holder) are removed from the surgical field, thus giving wide visual access for the stereotactic approach. Consequently, it is no longer necessary to remove the entire arc system, resulting in an increased operation safety and shorter operation times.

Optimized evaluation of a pulsed 2.09 microns holmium:YAG laser impact on the rat brain and 3 D-histomorphometry of the collateral damage

Since more than 20 years CO2 and Nd:YAG lasers are established in the microsurgery of the nervous system. CO2 lasers can be used handheld, but may be focused on the target area by mirror optics and sideports of the operating microscope's micromanipulator. Nd:YAG lasers have the disadvantage of deep penetration into the brain and provocation of a large collateral damage. The need is for a fibre conducted solid system for surgery in delicate areas as for brain stem surgery. Fibre conduction of near infrared lasers allows better exposure of the target area compared to hollow wave guides or mirror equipment. Fibres can be tapered and modified according to the purpose. The holmium:YAG (Ho:YAG) laser has acquired interest by introducing the system into microsurgery of parenchymal tissue. They have not been proven yet sufficiently for neurosurgical tasks. The effort to minimalize the collateral tissue damage has to be maximalized in the surgery of nervous tissue and functional low redundant brain stem or spinal cord tissue. Volumetric data may be more precise in comparison to depth and width data of the laser lesion even when the different levels of the tissue interaction have to be analyzed for estimation of the real side effects in nervous tissue. We have used 50-800 ml delivered Ho:YAG single pulses in cortical areas of Sprague-Dawley rats and investigated the different lesion zones by volumetric data. The functional lesion zone was detected and measured by immunohistological staining of the heat shock protein HSP 72. For further reduction of the focus area, we have used tapered 400 to 200 microns fibres.

A new forceps for the safe and easier insertion of subdural catheter: technical note

A new forceps suitable for the safe and easier insertion of a silicon catheter into the subdural space is described. The use of this new tool has two advantages: Firstly, the insertion of the silicon subdural catheter is parallel to the brain surface and secondly, the movement of the catheter's end in the subdural space is controlled with greater accuracy. Thus, the surgeon has the opportunity to direct the catheter to the right position avoiding penetration or injury of the brain.

MiniMATCH: a simple method for local data transfer between MRI and CT scan sets

A comparison of the spatial position of distinct locations within cranial MRI and CT scan sets can easily be done with a simple algorithm designed as a computer program. After determination of a basic system formed by the coordinates of anatomical landmarks in CT and MRI, arbitrary points can be identified on one scan set and transferred quantitatively to the other. Pros and cons of the method are discussed and opposed to the properties of specifically designed image processing systems.

A preliminary report on the use of relon mesh in the repair of eventrations with large parietal defects. An experimental study in rats

This experimental study in rats was designed to investigate the tolerability and the mode of healing when commercial relon mesh is used in the repair of large abdominal-wall defects. A defect was created to simulate anatomical derangement of the abdominal wall and a surgical correction was performed using relon mesh. The mesh was implanted intraperitoneally in 18 Wistar albino rats. The animals were killed under anaesthesia 4, 6, 8, 12, 15 or 30 days later and the intra-abdominal viscera were examined macroscopically for adhesions and other evidence of inflammatory reactions. Skin healing usually occurred within 7-8 days of surgery. Microscopic studies were used to confirm the gross findings and showed that maturation of granulation tissue, fibrocyte invasion with encapsulation of the mesh and the appearance of newly formed vessels occurred 2 weeks after surgery. Within 4 weeks a strong layer of connective tissue was present. The relon mesh was tolerated well. These results indicate that the use of relon mesh may provide a cheap alternative means of repairing large abdominal-wall defects.

Determination of the burr hole-site using the Brown-Roberts-Wells stereotactic system. A simple marking technique: technical note

The authors describe a new tool-set with which the determination of the burr hole-site using the BRW-stereotactic system can be done on a non-sterile-washed head. The described attainment permits an increased security, not only reducing exposure of the operative field to a minimum but also shortening the operative length. The use of this tool-set for marking smaller superficial cortical processes is also possible.

Greek physicians' and dentists' compliance with the British society for antimicrobial chemotherapy (BSAC) guidelines for preventing bacterial endocarditis

Two thousand questionnaires inquiring about applied prophylaxis for bacterial endocarditis were sent to practicing doctors in Greece. Two hundred and ninety-nine questionnaires were completed and returned (15% response rate) and were subsequently divided into two groups: Group A (163) consisting of responses from dentists, chest physicians and ear, nose and throat (ENT) specialists and group B (136) including responses from gastroenterologists, gynecologists, urologists and radiologists. The percentage of correct answers given in response by clinicians in Groups A and B to the main questions and in accordance with the 1992 guidelines of the British Society for Antimicrobial Chemotherapy (BSAC) were respectively: (a) 53% vs 35% asked patients their previous history pertaining to valve disease, rheumatic fever or prosthetic valve surgery; (b) 55% vs 33% administered prophylaxis to patients with relevant history prior to medical procedures; (c) 67% vs 0% of prescribing doctors administered the appropriate antibacterials; (d) 33% vs 31% initiated prophylaxis in proper timing prior to medical procedure; (e) 14% vs 13% administered antibiotics in correct time/route/duration of infusion where applicable, prior to medical procedure; (f) 7% of group A doctors administering recommended antibiotics, implemented prophylaxis with correct time/route/dosage while, although none of group B doctors administered recommended antibiotics, 7% implemented prophylaxis with correct time/route recommendations; (g) an overall 2% of doctors from both groups met the BSAC recommendations. In conclusion, it is imperative that the appropriate training of doctors in all subspecialties regarding prophylaxis of bacterial endocarditis and according to current recommendations be carried out.