Retraction Injury Research Articles

Midterm outcome of thoracic disc herniations that were treated by microdiscectomy with bilateral decompression via unilateral approach

Thoracic disc herniation (TDH) surgery carries risks of neurological worsening due to thoracic cord retraction injury. Multiple approaches have been developed aiming for resecting the disc herniations of the thoracic segment. We have conducted a prospective observational study to evaluate the mid-term outcome of thoracic microdiscectomy with bilateral decompression via a unilateral approach (BDUA). Patients were checked pre-operative, post-operative, and late follow-up by Oswestry Disability Index (ODI), Visual Analogue Scale (VAS), and radiological images. Twenty-three patients were treated for TDH by microdiscectomy with BDUA between January 2010 and January 2015. Nine patients were female, fourteen were male, and all of those mean age was 51,2 ± 8,3 (range 29–64 years). The mean follow-up time was 22,04 ± 8,59 months (range 13–58 m). The ODI and VAS scores decreased significantly in both postoperative and late follow-up evaluations. Microdiscectomy with BDUA for thoracic disc herniations allowed sufficient and safe decompression of the neural structures and resulted in a significant reduction of symptoms and disability.

Experimental study of needle recording electrodes placed on the thyroid cartilage for neuromonitoring during thyroid surgery.

Needle electrodes placed on the thyroid cartilage (TC) are an alternative to endotracheal tube (ET) electrodes for assessing recurrent laryngeal nerve (RLN) function during thyroid surgery. Needle electrodes placed on the TC were evaluated in an experimental porcine model. Continuous intraoperative neuromonitoring was used to record the electromyogram. Each TC side was delineated into nine areas to determine the optimal placement of the electrode, and needle electrode area, depth and orientation for optimal electromyographic (EMG) amplitudes were evaluated. RLN root locations were stimulated at four locations: vagus nerve distal to the neuromonitoring electrode, and most proximal, middle and laryngeal entry points of the nerve. A nerve retraction injury model was adapted to compare RLN monitoring by TC versus ET electrodes. An optimal site for placement of needle electrodes was identified, and electromyograms obtained from the various needle insertion depths and orientations were similar. Latencies recorded from the TC and ET electrodes were similar. The amplitude profile of TC electrodes responded earlier to RLN injury than that of ET electrodes. Amplitude and drop to loss of signal were also registered earlier. EMG amplitudes obtained using TC electrodes were higher, and identified RLN injury earlier than ET electrodes. Surgical relevance Needle electrodes placed on the thyroid cartilage (TC) are an alternative to endotracheal tube (ET) electrodes for assessing the function of the recurrent laryngeal nerve (RLN) in thyroid surgery. This study used an experimental porcine model to evaluate the use of needle electrodes inserted in the TC, compared with ET electrodes, for producing an electromyographic (EMG) profile of the RLN. Nine areas of the TC, with various needle insertion depths and orientations, were compared. Perichondral insertion into the avascular area of the TC was found to be safe. The EMG amplitude and latency features recorded via the TC and ET electrodes were compared, using both intermittent and continuous monitoring. Changes in EMG amplitudes in response to nerve traction injury were registered earlier with TC electrodes than with ET electrodes, and the amplitudes were higher and more stable. Latencies obtained via the TC and ET electrodes were similar. These results indicate that the development of a non-invasive monitoring electrode with improved function, easy placement and low cost is possible.

Contralateral Minimum Anterior and Posterior Combined Petrosal Approach for Retrochiasmatic Craniopharyngiomas: An Alternative Technique.

Retrochiasmatic craniopharyngiomas (RC) are a challenge for the neurosurgeon to treat surgically, restrained by their location in the interpeduncular fossa, surrounded by vital neurovascular structures, narrow corridor and poor visibility. Many approaches are possible and elucidated in the literature, which the surgeon chooses, based on multiple factors, such as the size of tumor, calcification, laterality, preoperative neurological deficits and the endocrine function status, recurrence, postradiotherapy status, or significant superior and/or posterior extension. 1 2 We describe a contralateral minimum anterior and posterior (CL-MAPC) petrosal approach for a case of recurrent RC, in a 37-year-old female patient operated before using a pterional approach, now presented with left homonymous hemianopia and panhypopituitarism ( Fig. 1 ). We preferred a contralateral approach to protect the ipsilateral optic tract (OT) from retraction injury, which formed an obstacle to the tumor from ipsilateral side. Apart from various benefits described by the author previously for RC, using MAPC petrosal approach, the CL-MAPC offers a safe corridor, protecting the ipsilateral OT, visualization of tumor origin usually posterior to chiasm, wider corridor if PCoM could be sacrificed, as it was done in this case, and pituitary stalk identification, with a probability of its functional preservation, unlike a necessity of pituitary transposition in EEA, though the endocrine outcome is poor after a radical resection irrespective of the approach chosen. 1 3 4 There was complete excision of the tumor with preservation of visual function postoperatively. We recommend the use of CL-MAPC as an alternative to EEA in some specific indications when the tumor is large, calcified, obscuring OT on the ipsilateral side and with significant lateral extension, which may be limiting factors in EEA ( Fig. 2 ). The link to the video can be found at: https://youtu.be/gWCJmh4_evs .

In Reply: Microsurgical Endoscope-Assisted Gravity-Aided Transfalcine Approach for Contralateral Metastatic Deep Medial Cortical Tumors

BACKGROUND Traditional approaches to deep medial cortical tumors utilize transcortical or ipislateral interhemispheric approaches, which can result in cortical damage or retraction injury. To reduce these risks, the microscopic transfalcine approach has been previously described. OBJECTIVE To describe this approach performed with endoscopic assistance for metastatic tumor resection, demonstrating appropriate and safe tumor resection without injury to the contralateral hemisphere. METHODS Eleven consecutive patients harboring medial, deep metastatic tumors are reported. Tumor resection was performed with endoscopic assistance with 2 surgeons. Clinical outcomes are recorded. RESULTS All 11 patients underwent safe tumor resection. Gross total resection was achieved in 73% of patients. The application of the angled endoscope allowed for further tumor resection in 91% of patients. There were no complications in these patients. The contralateral brain did not demonstrate clinical or radiographic injury as well. CONCLUSION This series suggests that the endoscopic transfalcine approach in the lateral position can be a safe and effective approach for resecting medial interhemispheric metastatic tumors. It allows excellent tumor visualization, eliminates the need for brain retraction, minimizes parenchymal transgression, and improves surgical ergonomics. A familiarity of endoscopy and neuroanesthesia support is helpful when utilizing this approach.

In Vivo Measurement of Surface Pressures and Retraction Distances Applied on Abdominal Organs During Surgery.

This study undertook the in vivo measurement of surface pressures applied by the fingers of the surgeon during typical representative retraction movements of key human abdominal organs during both open and hand-assisted laparoscopic surgery. Surface pressures were measured using a flexible thin-film pressure sensor for 35 typical liver retractions to access the gall bladder, 36 bowel retractions, 9 kidney retractions, 8 stomach retractions, and 5 spleen retractions across 12 patients undergoing open and laparoscopic abdominal surgery. The maximum and root mean square surface pressures were calculated for each organ retraction. The maximum surface pressures applied to these key abdominal organs are in the range 1 to 41 kPa, and the average maximum surface pressure for all organs and procedures was 14 ± 3 kPa. Surface pressure relaxation during the retraction hold period was observed. Generally, the surface pressures are higher, and the rate of surface pressure relaxation is lower, in the more confined hand-assisted laparoscopic procedures than in open surgery. Combined video footage and pressure sensor data for retraction of the liver in open surgery enabled correlation of organ retraction distance with surface pressure application. The data provide a platform to design strategies for the prevention of retraction injuries. They also form a basis for the design of next-generation organ retraction and space creation surgical devices with embedded sensors that can further quantify intraoperative retraction forces to reduce injury or trauma to organs and surrounding tissues.

Microsurgical Endoscope-Assisted Gravity-Aided Transfalcine Approach for Contralateral Metastatic Deep Medial Cortical Tumors.

Traditional approaches to deep medial cortical tumors utilize transcortical or ipislateral interhemispheric approaches, which can result in cortical damage or retraction injury. To reduce these risks, the microscopic transfalcine approach has been previously described. To describe this approach performed with endoscopic assistance for metastatic tumor resection, demonstrating appropriate and safe tumor resection without injury to the contralateral hemisphere. Eleven consecutive patients harboring medial, deep metastatic tumors are reported. Tumor resection was performed with endoscopic assistance with 2 surgeons. Clinical outcomes are recorded. All 11 patients underwent safe tumor resection. Gross total resection was achieved in 73% of patients. The application of the angled endoscope allowed for further tumor resection in 91% of patients. There were no complications in these patients. The contralateral brain did not demonstrate clinical or radiographic injury as well. This series suggests that the endoscopic transfalcine approach in the lateral position can be a safe and effective approach for resecting medial interhemispheric metastatic tumors. It allows excellent tumor visualization, eliminates the need for brain retraction, minimizes parenchymal transgression, and improves surgical ergonomics. A familiarity of endoscopy and neuroanesthesia support is helpful when utilizing this approach.

Endoscope-assisted repair of CSF otorrhea and temporal lobe encephaloceles via keyhole craniotomy.

OBJECTIVE Temporal lobe encephaloceles and cerebrospinal fluid otorrhea from temporal bone defects that involve the tegmen tympani and mastoideum are generally repaired using middle fossa craniotomy, mastoidectomy, or combined approaches. Standard middle fossa craniotomy exposes patients to dural retraction, which can lead to postoperative neurological complications. Endoscopic and minimally invasive techniques have been used in other surgeries to minimize brain retraction, and so these methods were applied to repair the lateral skull base. The goal of this study was to determine if the use of endoscopic visualization through a middle fossa keyhole craniotomy could effectively repair tegmen defects. METHODS The authors conducted a retrospective review of 6 cases of endoscope-assisted middle fossa repairs of tegmen dehiscences at a tertiary care medical center within an 18-month period. RESULTS All cases were successfully treated using a keyhole craniotomy with endoscopic visualization and minimal retraction. Surgical times did not increase. There were no major postoperative complications, recurrences of encephaloceles, or cerebrospinal fluid otorrhea in these patients. CONCLUSIONS Endoscopic visualization allows for smaller incisions and craniotomies and less risk of brain retraction injury without compromising repair integrity during temporal encephalocele and tegmen repairs.

Retractorless surgery for third ventricle tumor resection through the transcallosal approach

ObjectiveResection of tumors of the third ventricle through the transcallosal-interforniceal approach presents a surgical challenge with potential serious postoperative neurological deficits and complications. Retraction injury of the deep brain tissue and veins is a possible reason. Here, we aimed to investigate the feasibility and value of retractorless surgery in third ventricle tumor resection. Patients and methodsSince 2014, a total of 31 patients with third ventricle tumors were operated in our institution. All patients were operated using the transcallosal-interforniceal approach with a straight incision. The use of self-retaining retractor or constant retraction was not allowed. At the end of surgery, the opening of corpus callosum was sealed with fibrin glues. The degrees of tumor resection and postoperative neurological function deficits as well as complications were analyzed. The effect of retractorless surgery was evaluated according to the brain edema around the surgical approach on T2 imaging. ResultsThirty-one tumors were located in the anterior, middle, and posterior of the third ventricle. Total or gross total resection was achieved in 25 patients (80.6%). Postoperative neurological function deficits occurred in 4 patients (12.9%), and patients with mutism had a good recovery 3 weeks post-surgery. Retraction injuries around the surgical pathway were not obvious on T2 imaging. In addition, no subdural hygroma and subcutaneous fluid accumulation occurred. ConclusionsThe application of retractorless surgery in third ventricle tumors is feasible with enough exposure of tumors. This application could decrease the occurrence of postoperative neurological deficits and complications by avoiding the retraction injury on the deep brain structures.

Endoscope-Assisted Microsurgical Subtemporal Keyhole Approach to the Posterolateral Suprasellar Region and Basal Cisterns.

Refinements in optics and instrumentation have enabled surgeons to approach deep-seated intracranial diseases with reduced exposure and brain retraction. The anterior subtemporal keyhole approach is a minimally invasive route to the posterolateral aspect of the suprasellar area and petroclival region. In this cadaveric study, we show the benefits of endoscope-assisted microsurgical techniques in the anterior subtemporal keyhole approach. The anterior subtemporal keyhole approach was performed bilaterally on 5 formalin-fixed human specimens using standard microneurosurgical methods. Dissections compared the exposure afforded by the microsurgical route with the endoscope-assisted technique, using 0° and30° angled rod-lenses. Anatomic relationships among the surgical target and the surrounding neurovascular structures were described. Endoscope-assisted maneuvers enhanced the operative view afforded by the microscope and helped to minimize parenchymal retraction and neurovascular injury. Endoscope-assisted microsurgery provides a panoramic picture of the surgical target and its surroundings. It enables the operator to see into hidden corners beyond the microsurgical view. The endoscope provides enhanced visualization of the neurovascular structures located in the posterolateral suprasellar region, basal cisterns, upper clivus and midclivus, and interpeduncular region. Endoscope-assisted microsurgery provides a means to approach selected lesions located in the posterolateral suprasellar region, perimesencephalic cisterns, and upper clivus and midclivus. The operative view can be maximized by introducing the 0° and 30° angled endoscopes. Minimally invasive techniques help to optimize surgical exposure and lessen parenchymal retraction, thus improving control of the surrounding neurovascular structures.

Geographically Remote Cerebral Venous Sinus Thrombosis in Patients with Intracranial Tumors

Cerebral venous sinus thrombosis (CVST) related to intracranial tumors has most commonly been recognized as an operative complication related to local operative factors such as retraction or direct venous injury. CVST may also be caused by tumor-related factors such as local mass effect but rarely occurs geographically remote from the site of the tumor. We report 6 cases treated at our institution of intracranial supratentorial tumors associated with CVST. In each case, the CVST was remote from the surgical site. In 3 cases CVST was noted at the time of resection, and 3 cases occurred in a delayed fashion. Each case is discussed in detail, and the utility of intraoperative magnetic resonance imaging in the early diagnosis of this complication is highlighted.

Purely endoscopic pterional extradural approach: A novel technique for repair of cerebrospinal fluid rhinorrhea.

Study Design:Retrospective descriptive study of an innovative surgical technique.Objective:To assess the feasibility and success of repair of transfrontal sinus cerebrospinal fluid (CSF) rhinorrhea through pterional transcranial extradural approach using endoscope.Summary of Background Data:Repair of CSF rhinorrhea has seen advancement with the evolution of endoscopic transnasal techniques. However, leaks from defect in the posterior wall of frontal sinus still remain a challenge for the skull base surgeons and requires conventional craniotomy more often. We describe a novel technique to repair these leaks by purely endoscopic pterional extradural (PEPE) approach thereby avoiding complications associated with conventional craniotomy and endoscopic transnasal approaches.Materials and Methods:Thirty-five patients with traumatic CSF rhinorrhea from the posterior wall of frontal sinus underwent repair with the present technique. They were followed up for 6–18 months and were evaluated for feasibility of procedure, recurrence of leak, and occurrence of the fresh neurological deficit.Results:Thirty-five patients underwent CSF rhinorrhea repair using the above technique. The procedure was accomplished in all patients without any intraoperative complications. There was no requirement of blood transfusion in any case. All patients had a cessation of CSF leak in the postoperative period, and there was no recurrence. There was no evidence of frontal lobe retraction injury in any of these patients, and no fresh neurological deficit was observed.Conclusion:This PEPE approach to repair CSF leak through the posterior wall of the frontal sinus is a novel technique in which we can avoid disadvantages associated with both conventional craniotomy as well as transnasal endoscopic approaches.

Investigation on the Effects of Brain Retraction on Local Cerebral Metabolism Utilizing Microdialysis

In order to study the effect of brain retraction on local biochemical metabolism in brain tissue and to investigate the potential application of microdialysis in monitoring local cerebral metabolic and biochemical variations owing to brain retraction injury. Brain tissues were retracted based on different retraction pressures (30 mmHg, 40 mmHg, 50 mmHg) and retraction modes (intermittent and continuous tractions). Microdialysis was utilized for the dynamic collection of the dialysis fluid of extracellular fluid (ECF), and [Glu]d, [Lac]d, [Gly]d, [Gluta]d and L/P changes were observed. Different brain retraction pressures led to the changes of [Glu]d, [Lac]d, [Gly]d, [Gluta]d and L/P to various extents in ECF. Differences between the retraction group and control group before and after injury were significantly different (P<0.05). A higher retraction pressure resulted in a more significant change. Continuous retraction led to more serious brain damage than intermittent retraction. [Glu]d, [Lac]d, [Gly]d, [Gluta]d and L/P of the continuous retraction group changed more apparently, and the differences between the groups were significantly different (P<005). Microdialysis technique is ideal for the dynamic monitoring of local biochemical changed in brain tissues resulted from brain injury, which can be utilized as a valuable tool in monitoring brain retraction injury during neurosurgical operations.

Long-term clinical and echocardiographic outcomes of extensive septal myectomy for hypertrophic obstructive cardiomyopathy in Chinese patients.

BackgroundThere has been limited data addressing outcomes of extensive septal myectomy in Chinese patients with hypertrophic obstructive cardiomyopathy (HOCM). In this study, the objective was to evaluate the clinical and echocardiographic outcomes of extensive septal myectomy in a relative large number of Chinese HOCM patients over long-term follow-up.MethodsWe retrospectively studied 139 consecutive HOCM patients (age 43 ± 15 years, 37 % male) who underwent extensive left ventricular septal myectomy. During the perioperative period, all patients were examined by echocardiography. All-cause death and cardiac death were considered as primary endpoints during follow-up. Perioperative data was obtained by retrospective review of institutional surgical databases. Follow-up data of echocardiography and clinical status was recorded through outpatient interview.ResultsPerioperative events consisted of arrhythmia, retraction injury to aortic valve leaflets, pleural effusion, and hemodialysis and the use of intra-aortic balloon pump. There was no in-hospital mortality. The follow-up period averaged 5.6 ± 0.9 years and overall survivals were 100.0, 99.3, 99.3, 98.5 and 97.8 % at 1, 2, 3, 4 and 5 years, respectively. Left ventricular outflow tract (LVOT) gradient decreased form preoperative 84 ± 17 mmHg to 12 ± 3 mmHg at 2.5 years after surgery and it further reduced to 6 ± 3 mmHg at 5 years after surgery (P < 0.05). Compared with the preoperative levels, interventricualr septal thickness decreased by 32 % while diastole left ventricular inner diameter approximately increased by 10 % and ejection fraction (EF) was significantly elevated during follow-up (P < 0.05). By echocardiography detection, mitral regurgitation was ameliorated for HOCM patients after surgery. There was significant improvement in New York Heart Association (NYHA) class. The proportion of NYHA III and IV decreased from preoperative 58 to 19 % at 2.5 years after surgery and it reduced to 11 % at 5 years after operation.ConclusionExtensive septal myectomy offers minimal operative risk and provides long-term relief for LVOT obstruction in Chinese HOCM patients.

Resection of Deep-Seated Brain Lesions with the Use of an Expandable Soft Tubular Retractor—Case Series

Introduction Deep-seated brain lesions represent a neurosurgical challenge. A microsurgical resection requires a wide corridor and has a high incidence of brain retraction injury. Endoscope-assisted microsurgery through an expandable endoport can represent a solution.

Retractorless Surgery for Anterior Circulation Aneurysms via a Pterional Keyhole Approach

Brain retraction is required during many intracranial procedures to provide more working space. However, it is difficult to avoid brain retraction injury. Here, we report on retractorless surgery for anterior circulation aneurysms via a pterional keyhole approach. All patients undergoing a minimally invasive pterional keyhole approach within 3 days after hemorrhage by the same surgeon were included in the study. Patients were randomly assigned into group I (with the retractorless technique) and group II (with fixed retractors). Data on adequate clipping level, intraoperative ischemia induced by retraction, operation time, brain retraction injury, intraoperative blood loss, intraoperative aneurysm rupture, and modified Rankin Scale were collected for the 2 groups. A consecutive series of 47 patients (21 patients in group I, 26 patients in group II) successfully underwent a minimally invasive pterional keyhole approach. Statistical analysis revealed no significant between-group differences with regard to sex, age, Hunt-Hess grade, adequate clipping level, operation time, intraoperative blood loss, and aneurysm rupture (P > 0.05). However, no intraoperative ischemia was detected in group I, whereas 23.1% (6 of 26) of patients in group II had reversible ischemia. Furthermore, the proportion of brain retraction injuries in group I (5.3%) was lower than that in group II (34.6%). In addition, a better prognosis was obtained in patients who underwent retractorless surgery. With the careful and accurate use of a handheld suction device and operating instruments, the retractorless technique can replace fixed retraction, reduce brain retraction injury, and is applicable to surgeries on anterior circulation aneurysms via pterional keyhole approaches.

Telo-velar approach to fourth-ventricle tumours: how I do it.

The "telo-velar" approach is an alternative to cerebellar splitting to gain access to the fourth ventricle through the so-called cerebello-medullary fissure (CMF). In this approach, the CMF is exposed and access to the ventricle is obtained by incising the tela chorioidea and inferior medullary velum. This approach enables the exploration of the entire ventricle cavity from the obex to the aqueduct. The exposure of the fourth ventricle is satisfactory and the floor of the fourth ventricle can be visualised early and protected. The extent of resection and outcome are satisfactory in most patients, including those with large tumours or lesions attached to the lateral or superolateral recesses of the ventricle. The deep rostral tumour attachment is the main limitation of the telo-velar approach. • Early exposure of the interface lesion-floor of the fourth ventricle favours a safer tumour dissection. • We feel that resection of tonsils is not necessary in the surgical setting. • The posterior arch of C1 should be removed only if the tonsils are below the level of the foramen magnum. • The improved access to the lateral recess of the ventricle makes the telo-velar approach particularly effective in lesions attached to cerebellar peduncles. • The wide dissection of the cerebello-medullary fissure and gentle tonsils retraction may prevent from the occurrence of cerebellar mutism or other major cerebellar dysfunctions. • Even the bilateral opening of the CMF does not result in cerebellar mutism if wide and cautious dissection, avoiding retraction and vascular injuries, is obtained. • The exposure of the fourth ventricle was satisfactory also in patients harbouring lesions attached to the lateral or even the superolateral recesses of the ventricle. • A deep rostral tumour attachment seems to be, at least in our experience, the main specific limitation of the telo-velar approach. • The risk of hydrocephalus can be reduced by opening of the fissure bilaterally, exposing the aqueduct, and by cisterna magna-fourth ventricle communication augmentation. • The EVD is taken in place for 48-72 h to prevent possible abrupt increase of the intracranial pressure and to favour wound closure.

A 3D endoscopic transtubular transcallosal approach to the third ventricle.

Surgical approaches to deep-seated brain pathologies, specifically lesions of the third ventricle, have always been a challenge for neurosurgeons. In certain cases, the transcallosal approach remains the most suitable option for targeting lesions of the third ventricle, although retraction of the fornices and wall of the third ventricle have been associated with neuropsychological and hypothalamic deficits. The authors investigated the feasibility of an interhemispheric 3D endoscopic transcallosal approach through a minimally invasive tubular retractor system for the management of third ventricular lesions. Three-dimensional endoscopic transtubular transcallosal approaches were performed on 5 preserved cadaveric heads (10 sides). A parasagittal bur hole was placed using neuronavigation, and a tubular retractor was inserted under direct endoscopic visualization. Following observation of the vascular structures, fenestration of the corpus callosum was performed and the retractor was advanced through the opening. Transforaminal, interforniceal, and transchoroidal modifications were all performed and evaluated by 3 surgeons. This approach provided enhanced visualization of the third ventricle and more stable retraction of corpus callosum and fornices. Bayonetted instruments were used through the retractor without difficulty, and the retractor applied rigid, constant, and equally distributed pressure on the corpus callosum. A transtubular approach to the third ventricle is feasible and facilitates blunt dissection of the corpus callosum that may minimize retraction injury. This technique also provides an added degree of safety by limiting the free range of instrumental movement. The combination of 3D endoscopic visualization with a clear plastic retractor facilitates safe and direct monitoring of the surgical corridor.

The history of brain retractors throughout the development of neurological surgery

Early neurosurgical procedures dealt mainly with treatment of head trauma, especially skull fractures. Since the early medical writings by Hippocrates, a great deal of respect was given to the dura mater, and many other surgeons warned against violating the dura. It was not until the 19th century that neurosurgeons started venturing beneath the dura, deep into the brain parenchyma. With this advancement, brain retraction became an essential component of intracranial surgery. Over the years brain retractors have been created pragmatically to provide better visualization, increased articulations and degrees of freedom, greater stability, less brain retraction injury, and less user effort. Brain retractors have evolved from simple handheld retractors to intricate brain-retraction systems with hand-rest stabilizers. This paper will focus on the history of brain retractors, the different types of retractors, and the progression from one form to another.

Re-exploration of the craniotomy after surgical treatment of unruptured intracranial aneurysms

Unplanned re-exploration of the craniotomy after surgical treatment of unruptured intracranial aneurysms (UIAs) is sometimes required, but the underlying causes and rates of these procedures are seldom reported. This study retrospectively analyzed the causes of such re-explorations to identify methods for decreasing their necessity. From January 2000 to December 2011, 1,720 patients with a total of 1,938 UIAs underwent surgical treatment at our institution. From this cohort, 26 patients (1.5%) with 38 UIAs required re-exploration. Clinical data, aneurysm characteristics, treatment methods, and the incidence and causes of re-exploration of the craniotomy were analyzed for these 26 patients. Several causes of re-exploration were identified: compromised distal blood flow (eight patients, 0.47%), hemorrhagic venous infarction (four patients, 0.23%), brain retraction injury (three patients, 0.17%), newly identified aneurysms (three patients, 0.17%), bleeding from an incompletely clipped aneurysm (two patients, 0.12%), epidural hematoma (two patients, 0.12%), failed aneurysm clipping (two patients, 0.12%) and other causes (two patients, 0.12%). Annual re-exploration incidence rates ranged from 0 to 3.1%. Annual incidence rates gradually decreased following the introduction of several intraoperative monitoring systems. Precise surgical planning and careful operative techniques can reduce the incidence of unplanned re-exploration of the craniotomy. The introduction of various intraoperative monitoring systems can also contribute to a reduction in this incidence.

Microsurgical treatment and outcome of pediatric supratentorial cerebral cavernous malformation.

ObjectiveThe purpose of this study was to investigate the clinical features and outcomes of pediatric cavernous malformation (CM) in the central nervous system.MethodsTwenty-nine pediatric patients with supratentorial CM underwent microsurgical excision. In selected cases, transparent tubular retractor system (TTRS) was used to reduce retraction injury and intraoperative neuromonitoring (IONM) was held to preserve functioning cortex. Patients' demographics and symptoms were reviewed and surgical outcomes were discussed.ResultsThe main initial clinical manifestations included the following : seizures (n=13, 45%), headache (n=7, 24%), focal neurological deficits (n=3, 10%), and an incidental finding (n=6, 21%). Overt hemorrhage was detected in 7 patients (24%). There were 19 children (66%) with a single CM and 10 (34%) children with multiple CMs. In 7 cases with deep-seated CM, we used a TTRS to minimize retraction. In 9 cases which location of CM was at eloquent area, IONM was taken during surgery. There was no major morbidity or mortality after surgery. In the 29 operated children, the overall long-term results were satisfactory : 25 (86%) patients had no signs or symptoms associated with CMs, 3 had controllable seizures, and 1 had mild weakness.ConclusionWith the assistance of neuronavigation systems, intraoperative neuromonitoring, and TTRS, CMs could be targeted more accurately and excised more safely. Based on the satisfactory seizure outcome achieved, complete microsurgical excision in children is recommended for CMs presenting with seizures but removal of hemosiderin-stained areas seems to be unnecessary.