Stereotactic aqua stream and aspirator for hypertensive intracerebral hematoma

The stereotactic aqua stream and aspirator (SAS & A) is a modification of the aqua stream and aspirator (AS & A) designed for stereotactic evacuation of intracerebral hematoma. The needle of the new instrument is inserted into the brain through a burr hole by a conventional stereotactic technique and its tip is directed to the center of the hematoma. The hematoma is broken up with a stream of saline solution from a nozzle. Fragments of clot and fluid can then be aspirated piecemeal through the suction tube. The postoperative CT images show successful evacuation of the hematoma, and the clinical evaluation also showed satisfactory results. This instrument can be used safely, without any complications, early after the stroke.     

Stereotactic image-guided navigation in the preoperative imaging of perforators for DIEP flap breast reconstruction

Preoperative imaging is sought prior to DIEA (Deep Inferior Epigastric Artery) perforator flaps due to the potential for maximizing operative success and minimizing operative complications. Recent advances include the use of computed tomography (CT) angiography (CTA) and magnetic resonance angiography. Image-guided stereotactic surgery is a recent technique that has been used with success in several fields of surgery. The variability of perforator anatomy makes DIEA perforator flap surgery a suitable candidate for such technology, but as yet this has not been described. A study was undertaken to determine the feasibility of CT-guided stereotaxy technique in DIEA perforator flap surgery and to compare findings with both conventional CTA and operative findings. Five consecutive patients planned for an elective DIEA perforator flap were recruited. Each patient underwent preoperative imaging of the anterior abdominal wall vasculature with both conventional CTA and CT-guided stereotactic imaging. Imaging findings were compared to operative findings. In all cases, all the major perforators were accurately localized with stereotactic imaging and with conventional CTA. Stereotactic navigation demonstrated a slightly better (nonsignificant) correlation with perforator location than conventional CTA. As such, CT-guided stereotactic imaging is an accurate method for the preoperative planning of DIEA perforator flaps, providing additional and potentially more accurate data to conventional CTA. With no additional scanning required, the method described in this paper allows the combined use of both methods for preoperative planning.     

A simple stereotactic method for frameless deep brain stimulation

BACKGROUND: Deep brain stimulation (DBS) is widely used to treat advanced Parkinson's disease, other movement and psychiatric disorders. DBS implantation requires application of a stereotactic frame throughout a lengthy procedure, making it uncomfortable and tiring. We designed a stereotactic cube to stage the operation, perform frameless microelectrode recording (MER) and fix the DBS. METHODS: The 15-mm cube is implanted in a burr hole using bone cement. It contains 5 parallel trajectories (central + 4 around). It is aligned by stereotactic frame so that central trajectory reaches the target. Frameless MER is performed by attaching a micro-driver to the cube using 2-5 cannulae (4 cm). The DBS is fixed to the cube by a mini-plate and 1 screw. Ninety-six cubes were compared with 43 Bennet spheres (BS). RESULTS: No cube moved compared to 2 (5%) BS (p < 0.05). The final trajectory was central in 64.4% of cubes compared to 47.5% of BS, and the final target was >2 mm out in no cubes compared to 12.5% of BS (p < 0.01). Infection and haemorrhage were observed in 2.5% and 3.3% of cubes, respectively, while 5% of BS developed infection, 5% haemorrhage and 7.5% skin erosion. CONCLUSIONS: This method is simple and effective in staging DBS procedures, performing frameless MER and DBS implantation, fixation and revision.     

Modified One-piece Supraorbital Approach for Orbital Tumors: Widely Preserved Orbital Roof in a Self-fitting Flap

Objectives The one-piece supraorbital approach is a rational approach for the removal of orbital tumors. However, cutting the roof through the orbit is often difficult. We modified the technique to facilitate the osteotomy and improve the cosmetic effect. Design Three burr holes are made: the first, the MacCarty keyhole (burr hole 1), exposes the anterior cranial fossa and orbit; the second is placed above the supraorbital nerve (burr hole 2); and the third on the superior temporal line. Through burr hole 2, a small hole is created on the roof, 10 mm in depth. Next the roof is rongeured through burr hole 1 toward the preexisting small hole. Seamless osteotomies using a diamond-coated threadwire saw and the preexisting four holes are performed. Lastly the flap is removed. On closure, sutures are passed through holes in the cuts made with the threadwire saw, and tied. Results We applied our technique to address orbital tumors in two adult patients. The osteotomies in the roof were easy, and most parts of the roof were repositioned. Conclusions Our modification results in orbital osteotomies with greater preservation of the roof. Because the self-fitting flap does not require the use of fixation devices, the reconstruction is cosmetically satisfactory.     

Anchoring of methylmethacrylate filler to the calvarium--technical note

Implanted methylmethacrylate may be unexpectedly displaced due to poor adherence to the bone. We developed a simple technique to fix the material plugging the burr holes for use primarily in cosmetically important areas. At the closure of craniotomy, 2-3 small drill holes are made at the rim of the craniotomy burr hole. To address cranial defects in the pterional region, small holes are placed on the bone surface around the key burr hole. The holes extend into the diploic layer and have no parallel relationship. After fixation of the bone flap, a methylmethacrylate filler mixture is manually plugged into the burr hole and pushed into the small holes, thereby forming horns for secure fixation. None among over 100 patients developed an objectionable bulge attributable to displacement of the filler. Our technique requires no special instruments or materials and decreases the risk of cosmetic problems.     

Dual-floor burr hole adjusted to burr-hole ring and cap for implantation of stimulation electrodes. Technical note

Using a new perforator, the authors have developed a new dual-floor burr-hole method for use in deep brain stimulation therapy. The modification is called "dual-floor" because the usual 15-mm-diameter burr hole, which is located centrally and reaches the dura mater, is surrounded by a 4-mm-wide rim that is also planed downward by the new perforator to a depth of 4 mm. This dual-floor burr hole is adjusted to fit the burr-hole ring and cap that are are supplied by the electrode manufacturer. Such a method eliminates bulging of the scalp just over the burr-hole ring and cap. In addition, it is helpful for securing a tight fixation between the burr-hole ring and the skull.     

'Plunging' during burr hole craniostomy: a persistent problem amongst neurosurgeons in Britain and Ireland

The inadvertent 'plunging' of an instrument into the cranial cavity is a feared complication of drilling a burr hole and while anecdotes abound, little is known about the extent or the consequences of this problem. A survey by anonymous postal questionnaire of 304 neurosurgeons in Britain and Ireland was conducted to analyse the extent of this complication. Of respondents, 65.6% had experienced 'plunging', 22.3% having 'plunged' at least twice, indicating a high prevalence of this complication. The Cushing perforator was implicated by most. 'Plunging' carried a 12% risk of death or permanent neurological morbidity. The authors analyse the prevalence and significance of this preventable complication, and discuss various options available to minimize its occurrence.     

The "optimal" burr hole position for endoscopic third ventriculostomy: results from 31 stereotactically guided procedures.

ETV is a well established and successful method in contemporary neurosurgery. With growing experience there is a more efficient patient selection and further advances in technical know how. We evaluated retrospectively a consecutive group of 27 patients who were treated in our institution by stereotactic guided ETV between 1992 and 1996. When reviewing their postoperative imaging studies (MRI/CT) we could measure the position of the burr hole as port of entry for the rigid endoscope in 17 out of 23 finally selected patients. The median lateral position was 28 mm (mean 26.5 mm) from the midline and 8 mm (mean 6.5 mm) anterior of the coronal suture. We conclude that the optimal burr hole position should be 3 cm lateral to the midline and 1 cm anterior of the coronal suture, in the patients with normal anatomical findings.     

Number of burr holes as independent predictor of postoperative recurrence in chronic subdural haematoma

Chronic subdural haematoma (cSDH) is one of the most frequent neurosurgical entities. Current treatment options include burr hole craniostomy, twist drill craniostomy or craniotomy. While burr hole craniostomy is the most often used technique, there are no studies analysing the use of one vs. two burr holes in respect to recurrence rates and complications. This retrospective study included 76 (age: 60 +/- 12 years) patients presenting with cSDH admitted in our institution from January 2004 to December 2005. A total of 21 (27%) patients underwent bilateral craniostomy. The patients were assessed using the Markwalder Scale (2 +/- 0.71), Glasgow Coma Scale (14 +/- 1) and measuring the haematoma thickness (1.8 +/- 0.7 cm). The decision to perform one or two burr hole was made according to the personal preference of the treating neurosurgeon. All patients underwent irrigation and placement of closed-system drainage. Out of the 97 haematoma, 63 (65%) haematomas were treated with two burr holes, whereas 34 (35%) were treated with one burr hole. Patients with one burr hole had a statistically significant (p < 0.05) higher recurrence rate (29 vs. 5%), longer average hospitalization length (11 vs. 9 days) and higher wound infection rate (9% vs. 0%). A multivariate regression analysis identified the number of holes as single predictor for postoperative recurrence rate (r(2) = 0.12; p < 0.001). In this study, the treatment of cSDH with one burr hole only is associated with a significantly higher postoperative recurrence rate, longer hospitalization length and higher wound infection rate.     

Placement of deep brain stimulators into the subthalamic nucleus

We present our technique for deep brain stimulation (DBS) of the subthalamic nucleus (STN) and include information which may be helpful in general DBS. With the patient in a stereotactic head frame, the anterior and posterior commissures are identified on SPGR-sequence magnetic resonance imaging (MRI). STN coordinates are based on a stereotactic brain atlas at 12 mm lateral, 2 mm posterior and 5 mm caudal to the midcommissural point. Surgical navigation software allows for planning of the trajectory. Electromyography is used to quantitatively measure tremor responses to macrostimulation. Permanent lead placement is confirmed with intraoperative fluoroscopy and postoperative MRI.     

The impact of brain shift in deep brain stimulation surgery: observation and obviation

Background

The impact of brain shift on deep brain stimulation surgery is considerable. In DBS surgery, brain shift is mainly caused by CSF loss. CSF loss can be estimated by post-surgical intracranial air. Different approaches and techniques exist to minimize CSF loss and hence brain shift. The aim of this survey was to investigate the extent and dynamics of CSF loss during DBS surgery, analyze its impact on final electrode position, and describe a simple and inexpensive method of burr hole closure.

Methods

Sixty-six patients being treated with deep brain stimulation were retrospectively analyzed for this treatise. During surgery, CSF loss was minimized using bone wax as a burr hole closure. Intracranial air volume was calculated based on early post-surgery stereotactic 3D CT and correlated with duration of surgery and electrode deviations derived from post-surgery image fusion.

Results

Median early post-surgery intracranial air was 2.1?cm³ (range 0–35.7?cm³, SD 8.53?cm³). No correlation was found between duration of surgery and CSF-loss (R?=?0.078, p?=?0.534), indicating that CSF loss mainly occurs early during surgery. Linear regression analysis revealed no significant correlations regarding volume of intracranial air and electrode displacement in any of the three principal axes. No significant difference regarding electrode deviations between first and second side of surgery were observed.

Conclusions

CSF loss mainly occurs during the early phase of DBS surgery. CSF loss during a later phase of surgery can be effectively averted by burr hole closure. Postoperative intracranial air volumes up to 35?cm³ did not result in significant electrode displacement in our series. Comparing our results to studies previously published on this subject, burr hole closure using bone wax is highly effective.     

Cranial burr hole for revascularization in moyamoya disease

Currently, superficial temporal artery-middle cerebral artery (MCA) anastomosis, encephalomyosynangiosis (EMS), and encephalo-duro-arterio-synangiosis are used to treat moyamoya disease and are reported to effectively improve ischemic symptoms. All are methods of reversing the flow of blood from the external carotid artery system into the cortical branches of the MCA. As moyamoya disease advances, these operations alone will predictably not correct the deterioration in blood flow in the territory of the anterior cerebral artery. It was noted in a case of moyamoya disease with intraventricular hemorrhage that a burr hole, made in the frontal region for drainage purposes, induced marked neovascularization. Since then, similar frontal burr holes have been made in five juvenile cases of moyamoya disease; this procedure involved making a burr hole in both frontal bones and incising both the dura and the arachnoid membrane. In two cases a frontal burr hole in both frontal bones and incising both the dura and the arachnoid membrane. In two cases a frontal burr hole was placed simultaneously with EMS, and in the others the frontal burr hole was made following EMS. The clinical symptoms improved after the frontal burr hole was made, and dynamic computerized tomography revealed improved circulation in the frontal regions. Together with conventional surgical therapy for juvenile cases of moyamoya disease, this operation is considered beneficial both to the circulation in the frontal region and for the protection of frontal brain function.     

Correlation between MRI-based stereotactic thalamic deep brain stimulation electrode placement, macroelectrode stimulation and clinical response to tremor control

In this study we compared the position of the electronically active contact of the thalamic (Vim) deep brain stimulation (DBS) electrode to the stereotactic location of its tip. Fifteen patients with either Parkinson's disease (PD) or essential tremor (ET) underwent stereotactic, MRI-based placement of the Medtronic quadripolar DBS electrode. An overall improvement of 69% was achieved in the tremor scores during a period of 1-13 months after implantation of the DBS electrode. Eleven patients with ET showed 70% clinical improvement of tremor, compared to a 58% response observed in the 4 patients with PD. The electrode tip center was 11.2 +/- 1.54 mm lateral to the third ventricular wall, 5.38 +/- 1.02 mm anterior to the posterior commissure and 2.9 +/- 3.57 mm inferior to the level of AC-PC line. The most significant deviation from the planned stereotactic target was observed in the Z-coordinate. In our group of patients, stimulation settings favored the contacts closer to the AC-PC line, correcting the electrode tip position to 0.80 +/- 2.84 mm (p < 0.001) inferior to the level of the AC-PC line. In our experience, thalamic DBS offers a reversible and adjustable 'lesion' to compensate for the anatomic variabilities encountered in the positioning of the DBS electrode tip.     

A sine-wave-shaped skin incision for inserting deep-brain stimulators

Background

The sine-wave-shaped skin incision is a technique that minimizes skin-related complications near burr hole caps after electrode placement for deep-brain stimulation (DBS).

Methods

Between 2011 and 2013, 54 DBS electrodes were implanted in 27 consecutive patients with Parkinson’s disease (PD), essential tremor, or dystonia. The sine-wave incision was used in 26 patients and conventional bilateral linear scalp incisions were used in one patient.

Results

None of the patients whose operations involved sine-wave-shaped incisions developed hardware-linked complications such as skin infection or skin erosion. The one patient who underwent conventional bilateral linear scalp incisions developed a skin infection.

Conclusion

By preserving the vascular anatomy of the scalp and reducing skin tension at the wound site, the sine-wave-shaped incision promotes wound healing.     

Fronto-orbital advancement by distraction: the latest modification

In 1996 the authors performed the first fronto-orbital advancement by distraction osteogenesis in a patient with coronal synostosis, and they have refined the surgical technique since then. Their latest technique has the following features: 1) the osteotomy lines are almost identical to those of conventional fronto-orbital advancement except for the lack of supraorbital osteotomy and tongue-in-groove osteotomy; 2) burr holes are placed at the pterion just behind the sphenoid wing and at the bregma lateral to the anterior fontanel bilaterally, and another burr hole is placed on the glabella 1 cm above the nasion; 3) to gain access to the lateral portion of the anterior cranial base, a 7- to 10-mm-wide segment of bone is removed at the pterion using rongeurs; 4) the sphenoid ridge is widely removed; and 5) osteotomy is performed using a Gigli saw and rongeurs. They report their latest technique.     

Chronic subdural haematomas: a comparative study of an enlarged single burr hole versus double burr hole drainage

Various surgical treatments have been proposed for the treatment of chronic subdural haematoma (CSDH). Herewith, we set out to compare the efficacy of an enlarged single burr hole versus double burr hole drainage for the treatment of CSDH. We studied patients with symptomatic CSDH proven by CT scan that were treated in our institute between January 2002 and January 2009. All patients were treated by an enlarged single or double burr hole drainage. A subdural drain was placed in all cases. A total of 245 patients were included in the study. Double hole drainage was performed in 156 (63.7 %) patients (group A) and an enlarged single burr hole drainage in 89 (36.3 %) patients (group B). There were nine recurrences in group A and five in group B; however, the difference was not statistically significant. There was no significant relationship between recurrence rate and age, gender, bilateral haematoma and antiplatelet or anticoagulant therapy. There was a trend towards higher risk of recurrence for patients with residual clots on postoperative CT scan. The mean hospitalization time was 6.2 days, and there was no significant difference between the two groups. No significant difference was found between patients' outcome, as assessed by Glasgow outcome scale score, and treatment method. Enlarged single burr hole and double burr hole drainage had the same efficacy in the treatment of CSDH.     

Supratentorial craniotomy using a threadwire saw. Technical note

An alternative technique for cutting the bone flap in supratentorial craniotomy uses a threadwire saw (T-saw), originally developed for spinal surgery. After placing a burr hole at each corner of the intended craniotomy, osteotomy is performed between adjacent burr holes using a craniotome, leaving a bony bridge of approximately 1/3 of the length of the osteotomy. The T-saw is introduced between adjacent burr holes through the epidural space and the bridge is cut with reciprocating strokes. The narrow beveled cut reduces the bone gap for fitted bone flap fixation. On closure, the bridge firmly supports the flap and only sutures are needed for fixation. A minimal amount of filler is required to fill the bone gap. Successful bone flap fixation was obtained in more than 100 cases. No technique-related complications such as dural laceration or flap displacement occurred. Osteotomy using a T-saw was somewhat time-consuming, but cutting efficiency was improved with a Diamond T-saw, featuring a section of cable covered with diamond particles. This method is ideal for bone cuts in cosmetic cranioplasty; is easy and safe to perform, is inexpensive, and avoids the need for flap fixation with metal devices.     

Ultrasound-guided aspiration of brain abscesses through a single burr hole.

Surgical aspiration and/or drainage of brain abscesses is considered to be the first-line treatment for abscesses larger than 25 mm. This is ususally performed with the aid of CT-guided stereotaxy. A method of ultrasound guidance is presented that allows a single burr hole approach with real-time imaging of the whole procedure. A bayonet-like shaped ultrasound probe with tip dimension of 8 x 8 mm only (EUP-NS 32, Hitachi/Ecoscan) with frequencies of 3.5 and 5 MHz is used. After placement of a burr hole the target is identified by transdural insonation, a guideline is adjusted and a mounted puncture-adapter guides the cannula towards the lesion under real-time imaging control. Up to now 12 abscesses in 10 patients were treated. Visualization was always excellent. A second aspiration had to be performed twice. One abscess did not contain enough pus to be cured by aspiration and was removed by open surgery, another could not be tapped by the blunt cannula and was aspirated under stereotactic control using a sharp trocar. Outcome was excellent in 6 patients and fair in 2 patients but this was due to the pre-existing disease. Two patients admitted in deep coma died despite an emergency operation. The presented method has proven to be a very powerful guiding tool in the surgical treatment of brain abscesses through a single burr hole approach.     

Freehand technique for putaminal hemorrhage--technical note

We designed a new endoscopic surgical procedure for putaminal hemorrhage (freehand technique) and evaluated its effectiveness and safety in patients with putaminal hemorrhage. Computed tomography (CT) data sets from 40 healthy patients were used. The CT data were transformed into three-dimensional images using AZE VirtualPlace(TM) Plus. The nasion and external auditory foramen were the intraoperative reference points. The median point from medial of the globus pallidus to the insula was the target point. The location of the burr hole point was 80-125 mm above and 27.5 mm lateral to the nasion, and the direction was parallel to the midline and a line drawn from the burr hole to the ipsilateral external auditory foramen. This point was used for 15 patients with putaminal hemorrhage. In all cases, only one puncture was required, and there were no complications. The median surgical time was 91.7 minutes, and the median hematoma removal rate was 95.9%. No recurrent bleeding or operative complications occurred. The freehand technique is a simple and safe technique for patients with putaminal hemorrhage. We believe that this technique of endoscopic hematoma evacuation may provide a less-invasive method for treating patients with putaminal hemorrhage.