A new minimally invasive tubular brain retractor system for surgery of deep intracerebral hematoma

Indian Neurosurgeons at the Forefront: A Comprehensive Exploration of their Pioneering Contributions to Neuroendoscopy

This article delves into the profound impact of Indian neurosurgeons on the expansive canvas of neuroendoscopy. By scrutinizing their trailblazing research, innovations, new surgical techniques, and relentless dedication to education and training, we aim to unravel the intricacies of their influence on a global scale. The review, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, conducts a comprehensive analysis of the literature related to neuroendoscopy contributed by Indian neurosurgeons. The exploration covers a spectrum of achievements, ranging from pioneering research and innovations to complication avoidance, neuroendoscopic training, and global recognition. Despite challenges, Indian neurosurgeons continue to lead the way in shaping the future of neuroendoscopy, ensuring better patient outcomes and improved quality of life. Many Indian neurosurgeons have contributed significantly to the development of neuroendoscopy in India. Prof. YR Yadav's contributions stand significant in the form of research articles and publications on almost all subjects on neuroendoscopy, the textbook on neuroendoscopy, popularizing neuroendoscopy by starting the first university-certified neuroendoscopy fellowship training program in India, describing many innovative techniques/first report of endoscopic techniques and conducting regular endoscopic workshops in his institutions and other major cities of India.

Impact of Preoperative Mapping and Intraoperative Neuromonitoring in Minimally Invasive Parafascicular Surgery for Deep-Seated Lesions

BACKGROUND

Transsulcal tubular retractor-assisted minimally invasive parafascicular surgery changes the surgical strategy for deep-seated lesions by promoting a deficit-sparing approach. When integrated with preoperative brain mapping and intraoperative neuromonitoring (IONM), this approach may potentially improve patient outcomes. In this study, we assessed the impact of preoperative brain mapping and IONM in tubular retractor-assisted neuro-oncological surgery.

METHODS

This retrospective single-center cohort study included patients who underwent transsulcal tubular retractor-assisted minimally invasive parafascicular surgery for resection of deep-seated brain tumors from 2016 to 2022. The cohort was divided into 3 groups: group 1, no preoperative mapping or IONM (17 patients); group 2, IONM only (25 patients); group 3, both preoperative mapping and IONM (38 patients).

RESULTS

We analyzed 80 patients (33 males and 47 females) with a median age of 46.5 years (range: 1-81 years). There was no significant difference in mean tumor volume (26.2 cm3 [range 1.07-97.4 cm3]; P = 0.740) and mean preoperative depth of the tumor (31 mm [range 3-65 mm], P = 0.449) between the groups. A higher proportion of high-grade gliomas and metastases was present within group 3 (P = 0.003). IONM was related to fewer motor (P = 0.041) and language (P = 0.032) deficits at hospital discharge. Preoperative mapping and IONM were also related to shorter length of stay (P = 0.008).

CONCLUSIONS

Preoperative and intraoperative brain mapping and monitoring enhance transsulcal tubular retractor-assisted minimally invasive parafascicular surgery in neuro-oncology. Patients had a reduced length of stay and prolonged overall survival. IONM alone reduces postoperative neurological deficit.

Neuroendoscopy in the Surgical Management of Lateral and Third Ventricular Tumors: Looking Beyond Microneurosurgery

Background

Intraventricular tumors pose a surgical challenge because of the difficulty in reaching their deep location through safe corridors and their adherence or proximity to vital neurovascular structures. Although microneurosurgery is the mainstay of surgical management, neuroendoscopy aided by adjuncts, namely, navigation and ultrasonic aspirators, has made a great contribution to improving surgical results.

Objective

This article reviews the experience of a neurosurgical unit with endoscopic procedures for intraventricular tumors. The current indications, benefits, and complications of neuroendoscopy are described.

Materials and Methods

This is a retrospective, observational study of lateral and third ventricular tumors tackled either purely with an endoscope or with its assistance over 19 years in a single unit at Bombay Hospital Institute of Medical Sciences, Mumbai.

Results

Of a total of 247 operated patients with intraventricular tumors, 85 cases operated using an endoscope were included. The majority of the patients had a tumor in the third ventricle (n = 62), whereas 23 patients had tumor in the lateral ventricle. The most common pathologies were colloid cyst and arachnoid cyst (n = 18). An endoscope was used for microsurgical assisted excision of tumors in 31 cases, biopsy in 24, cyst fenestration in 23, and pure endoscopic excision in seven cases.

Conclusion

Microsurgery remains the gold standard for the removal of giant, vascular intraventricular tumors. However, endoscopic fenestration or excision of cysts and biopsy have become better alternatives in many cases. Endoscope-assisted microsurgery affords safety and helps in achieving a more complete excision.

Endoscope-controlled Access to Thalamic Tumors using Tubular Brain Retractor: An Alternative Approach to Microscopic Excision

BACKGROUND

 Surgery for thalamic lesions has been considered challenging due to their deep-seated location. Endoscopic excision of deep-seated brain tumors using tubular retractor has been shown to be safe and effective in prior studies; however, there are limited reports regarding its use for thalamic tumors. We present our experience of endoscope-controlled resection of thalamic tumors using a tubular retractor.

MATERIAL AND METHODS

 This was a prospective observational case series done at a tertiary center specialized for endoscopic neurosurgery during the period from 2010 to 2019. Surgeries were performed under the endoscopic control using a silicon tubular retractor. Lesions were approached transcortically or trans-sulcally. Data were collected for the extent of resection, amount of blood loss, operative time, need for conversion to microscopy, and complications.

RESULTS

 Twenty-one patients of thalamic masses of 14- to 60-year age underwent the surgeries. Pathologies ranged from grade I to IV gliomas. Gross total and near-total resection could be done in 42.85% of cases for each group. The average blood loss and operative time were164.04 ± 83.63 mL and 157.14 ± 28.70 minutes, respectively. Complications included a small brain contusion, two transient hemipareses, and one transient speech deficit.

CONCLUSION

 Endoscopic excision of thalamic tumors using a tubular retractor was found to be a safe and effective alternative to microscopic resection.

Management of large intraventricular meningiomas with minimally invasive port technique: a three-case series

The use of minimally invasive transcranial ports for the resection of deep-seated lesions has been shown to be safe and effective. To date, most of the literature regarding the tubular retractors used in brain surgery is comprised of individual case reports that describe the successful resection of deep-seated lesions such as thalamic pilocytic astrocytomas, colloid cysts in the third ventricle, hematomas, and cavernous angiomas. The authors describe their experience using a tubular retractor system with three different cases involving large intraventricular meningiomas and examine radiographic and patient outcomes. A single-institution, retrospective case series was performed from a skull base database. Patients who underwent resection of intraventricular > 4-cm meningiomas with port technology were identified. The authors reviewed three cases to illustrate the feasibility of minimal access port surgery for the resection of these lesions. Complete resection was achieved in all cases. None of the patients developed permanent neurological deficits. There were no major complications related to surgery and no mortalities. Good clinical and surgical outcomes for atrium meningiomas can be achieved through the minimally invasive port technique and tumor size does not appear to be a limitation.

Combination of the tubular retractor and brain spatulas provides an adequate operative field in surgery for deep-seated lesions: Case series and technical note

Background:

Surgeries for deep-seated lesions are challenging because making a corridor and observing the interface between lesions and normal brain tissue are difficult. The ViewSite Brain Access System, which is a clear plastic tubular retractor system, is used for resection of deep-seated lesions. However, the tapered shape of this system may result in limitation of the surgical field and cause brain injury to observe the interface between lesions and normal tissue. In this study, we evaluated the usefulness of the combination of ViewSite and brain spatulas.

Methods:

Nine patients were retrospectively identified who underwent resection of deep-seated lesions with the combination of Viewsite and brain spatulas. We assessed the extent of resection, prognosis, and quantitative brain injury from postoperative diffusion-weighed imaging (DWI).

Results:

There were four total radiographically confirmed resections. Subtotal resection in four patients and partial resection in one with central neurocytoma were achieved because these tumors were strongly adherent to the choroid plexus and ependymal veins. Only one case of metastatic tumor relapsed 6 months after surgery. The mean postoperative high signal on DWI was 3.68 ± 0.80 cm³.

Conclusions:

The combination of ViewSite and brain spatulas provides wide and adequate operative fields to observe the interface between lesions and normal tissue, and to prevent brain injury from excessive retraction pressure on the brain derived from repositioning of the ViewSite. Postoperative 3D volumetric analysis shows minimal damage to normal brain tissue. This report may provide new insight into the use of the ViewSite tubular retractor.

Smartphone-assisted minimally invasive neurosurgery

OBJECTIVE

Advances in video and fiber optics since the 1990s have led to the development of several commercially available high-definition neuroendoscopes. This technological improvement, however, has been surpassed by the smartphone revolution. With the increasing integration of smartphone technology into medical care, the introduction of these high-quality computerized communication devices with built-in digital cameras offers new possibilities in neuroendoscopy. The aim of this study was to investigate the usefulness of smartphone-endoscope integration in performing different types of minimally invasive neurosurgery.

METHODS

The authors present a new surgical tool that integrates a smartphone with an endoscope by use of a specially designed adapter, thus eliminating the need for the video system customarily used for endoscopy. The authors used this novel combined system to perform minimally invasive surgery on patients with various neuropathological disorders, including cavernomas, cerebral aneurysms, hydrocephalus, subdural hematomas, contusional hematomas, and spontaneous intracerebral hematomas.

RESULTS

The new endoscopic system featuring smartphone-endoscope integration was used by the authors in the minimally invasive surgical treatment of 42 patients. All procedures were successfully performed, and no complications related to the use of the new method were observed. The quality of the images obtained with the smartphone was high enough to provide adequate information to the neurosurgeons, as smartphone cameras can record images in high definition or 4K resolution. Moreover, because the smartphone screen moves along with the endoscope, surgical mobility was enhanced with the use of this method, facilitating more intuitive use. In fact, this increased mobility was identified as the greatest benefit of the use of the smartphone-endoscope system compared with the use of the neuroendoscope with the standard video set.

CONCLUSIONS

Minimally invasive approaches are the new frontier in neurosurgery, and technological innovation and integration are crucial to ongoing progress in the application of these techniques. The use of smartphones with endoscopes is a safe and efficient new method of performing endoscope-assisted neurosurgery that may increase surgeon mobility and reduce equipment costs.

BrainPath-Mediated Resection of a Ruptured Subcortical Arteriovenous Malformation

BACKGROUND

Although tubular retractor systems have gained popularity for other indications, there have been few reports of their use for arteriovenous malformation (AVM) surgery. A patient was diagnosed with a ruptured 1.2-cm subcortical AVM after presenting with intracerebral hemorrhage in the right frontal lobe and anterior basal ganglia. The characteristics of this AVM made it amenable to resection using a tubular retractor.

OBJECTIVE

To demonstrate the feasibility and safety of AVM resection using a tubular retractor system.

METHODS

Resection of the ruptured 1.2-cm subcortical AVM was performed utilizing the BrainPathTM (NICO corp, Indianapolis, Indiana) tubular retractor system.

RESULTS

The BrainPathTM approach provided sufficient visualization and surgical freedom to permit successful AVM resection and hematoma evacuation. Postoperative imaging demonstrated near total hematoma removal and angiographic obliteration of the AVM. There were no complications, and the patient made an excellent recovery.

CONCLUSION

Tubular retractors warrant consideration for accessing small, deep, ruptured AVMs. The nuances of such systems and their role in AVM surgery are discussed.

Indigenous Inexpensive Practice Models for Skill Development in Neuroendoscopy

Introduction:

Neurosurgery is a branch having a tough learning curve. Residents generally get very less hands-on exposure for advanced procedures like neuroendoscopy. With the limited number of cadavers available and ethical issues associated with animal models, practice models, and simulators are becoming the able alternative. Most of these simulators are very costly. We tried to build indigenous inexpensive practice models that can help in developing most of the skills of neuroendoscopy.

Materials and Methods:

Models were built for learning hand-eye coordination, dexterity, instrument manipulation, cutting, fine dissection, keyhole concept, drilling, and simulation of laminectomy and ligamentum flavum resection. These were shown in the neuroendoscopic fellowship program conducted in authors' institute, and trainees' responses were recorded.

Results:

Both novice and experienced neuroendoscopic surgeons validated the models. There was no significant difference between their responses (P = 0.791).

Conclusion:

Indigenous innovative models can be used to learn and teach neuroendoscopic skills. The presented models were reliable, valid, eco-friendly, highly cost-effective, portable, easily made and can be kept in one's chamber for practicing.

Learning neuroendoscopy with an exoscope system (video telescopic operating monitor): Early clinical results

CONTEXT

Steep learning curve is found initially in pure endoscopic procedures. Video telescopic operating monitor (VITOM) is an advance in rigid-lens telescope systems provides an alternative method for learning basics of neuroendoscopy with the help of the familiar principle of microneurosurgery.

AIMS

The aim was to evaluate the clinical utility of VITOM as a learning tool for neuroendoscopy.

MATERIALS AND METHODS

Video telescopic operating monitor was used 39 cranial and spinal procedures and its utility as a tool for minimally invasive neurosurgery and neuroendoscopy for initial learning curve was studied.

RESULTS

Video telescopic operating monitor was used in 25 cranial and 14 spinal procedures. Image quality is comparable to endoscope and microscope. Surgeons comfort improved with VITOM. Frequent repositioning of scope holder and lack of stereopsis is initial limiting factor was compensated for with repeated procedures.

CONCLUSIONS

Video telescopic operating monitor is found useful to reduce initial learning curve of neuroendoscopy.

Endoscopic management of cerebrospinal fluid rhinorrhea

Cerebrospinal fluid (CSF) rhinorrhea occurs due to communication between the intracranial subarachnoid space and the sinonasal mucosa. It could be due to trauma, raised intracranial pressure (ICP), tumors, erosive diseases, and congenital skull defects. Some leaks could be spontaneous without any specific etiology. The potential leak sites include the cribriform plate, ethmoid, sphenoid, and frontal sinus. Glucose estimation, although non-specific, is the most popular and readily available method of diagnosis. Glucose concentration of > 30 mg/dl without any blood contamination strongly suggests presence and the absence of glucose rules out CSF in the fluid. Beta-2 transferrin test confirms the diagnosis. High-resolution computed tomography and magnetic resonance cisternography are complementary to each other and are the investigation of choice. Surgical intervention is indicated, when conservative management fails to prevent risk of meningitis. Endoscopic closure has revolutionized the management of CSF rhinorrhea due to its less morbidity and better closure rate. It is usually best suited for small defects in cribriform plate, sphenoid, and ethmoid sinus. Large defects can be repaired when sufficient experience is acquired. Most frontal sinus leaks, although difficult, can be successfully closed by modified Lothrop procedure. Factors associated with increased recurrences are middle age, obese female, raised ICP, diabetes mellitus, lateral sphenoid leaks, superior and lateral extension in frontal sinus, multiple leaks, and extensive skull base defects. Appropriate treatment for raised ICP, in addition to proper repair, should be done to prevent recurrence. Long follow-up is required before leveling successful repair as recurrences may occur very late.

Comparison of endoscope- versus microscope-assisted resection of deep-seated intracranial lesions using a minimally invasive port retractor system

OBJECT

Tubular brain retractors may improve access to deep-seated brain lesions while potentially reducing the risks of collateral neurological injury associated with standard microsurgical approaches. Here, microscope-assisted resection of lesions using tubular retractors is assessed to determine if it is superior to endoscope-assisted surgery due to the technological advancements associated with modern tubular ports and surgical microscopes.

METHODS

Following institutional approval of the tubular port, data obtained from the initial 20 patients to undergo transportal resection of deep-seated brain lesions were analyzed in this study. The pathological entities of the resected tissues included metastatic tumors (8 patients), glioma (7), meningioma (1), neurocytoma (1), radiation necrosis (1), primitive neuroectodermal tumor (1), and hemangioblastoma (1). Surgery incorporated endoscopic (5 patients) or microscopic (15) assistance. The locations included the basal ganglia (11 patients), cerebellum (4), frontal lobe (2), temporal lobe (2), and parietal lobe (1). Cases were reviewed for neurological outcomes, extent of resection (EOR), and complications. Technical data for the port, surgical microscope, and endoscope were analyzed.

RESULTS

EOR was considered total in 14 (70%), near total (> 95%) in 4 (20%), and subtotal (< 90%) in 2 (10%) of 20 patients. Incomplete resection was associated with the basal ganglia location (p < 0.05) and use of the endoscope (p < 0.002). Four of 5 (80%) endoscope-assisted cases were near-total (2) or subtotal (2) resection. Histopathological diagnosis, presenting neurological symptoms, and demographics were not associated with EOR. Complication rates were low and similar between groups.

CONCLUSIONS

Initial experience with tubular retractors favors use of the microscope rather than the endoscope due to a wider and 3D field of view. Improved microscope optics and tubular retractor design allows for binocular vision with improved lighting for the resection of deep-seated brain lesions.

Endoscopic inter laminar management of lumbar disease

Discectomy for lumbar disc provides faster relief in acute attack than does conservative management. Long-term results of open, microscopy-, and endoscopy-assisted discectomy are same. Early results of endoscopy-assisted surgery are better as compared to that of open surgery in terms of better visualization, smaller incision, reduced hospital stay, better education, lower cost, less pain, early return to work, and rehabilitation. Although microscopic discectomy also has comparable advantages, endoscopic-assisted technique better addresses opposite side pathology. Inter laminar technique (ILT) and trans foraminal technique (TFT) are two main endoscopic approaches for lumbar pathologies. Endoscopy-assisted ILT can be performed in recurrent, migrated, and calcified discs. All lumbar levels including L5-S1 level, intracanalicular, foraminal disc, lumbar canal and lateral recess stenosis, multiple levels, and bilateral lesions can be managed by ILT. Migrated, calcified discs, L5-S1 pathology, lumbar canal, and lateral recess stenosis can be better approached by ILT than by TFT. Most spinal surgeons are familiar with anatomy of ILT. It can be safely performed in foramen stenosis and in uncooperative and anxious patients. There is less risk of exiting nerve root damage, especially in short pedicles and in presence of facet osteophytes as compared to TFT. On the other hand, ILT is more invasive than TFT with more chances of perforations of the dura matter, pseudomeningocele formation, and cerebrospinal fluid fistula in early learning curve. Obtaining microsurgical experience, attending workshops, and suitable patient selection can help shorten the learning curve. Once adequate skill is acquired, this procedure is safe and effective. The surgeon must be prepared to convert to an open procedure, especially in early learning curve. Spinal endoscopy is likely to achieve more roles in future. Endoscopy-assisted ILT is a safer alternative to the microscopic technique.

Role of endoscopic third ventriculostomy in tuberculous meningitis with hydrocephalus

Hydrocephalus is one of the commonest complications of tuberculous meningitis (TBM). It can be purely obstructive, purely communicating, or due to combinations of obstruction in addition to defective absorption of cerebrospinal fluid (CSF). Endoscopic third ventriculostomy (ETV) as an alternative to shunt procedures is an established treatment for obstructive hydrocephalus in TBM. ETV in TBM hydrocephalus can be technically very difficult, especially in acute stage of disease due to inflamed, thick, and opaque third ventricle floor. Water jet dissection can be helpful in thick and opaque ventricular floor patients, while simple blunt perforation is possible in thin and transparent floor. Lumbar peritoneal shunt is a better option for communicating hydrocephalus as compared to VP shunt or ETV. Intraoperative Doppler or neuronavigation can help in proper planning of the perforation to prevent neurovascular complications. Choroid plexus coagulation with ETV can improve success rate in infants. Results of ETV are better in good grade patients. Poor results are observed in cisternal exudates, thick and opaque third ventricle floor, acute phase, malnourished patients as compared to patients without cisternal exudates, thin and transparent third ventricle floor, chronic phase, well-nourished patients. Some of the patients, especially in poor grade, can show delayed recovery. Failure to improve after ETV can be due to blocked stoma, complex hydrocephalus, or vascular compromise. Repeated lumbar puncture can help faster normalization of the raised intracranial pressure after ETV in patients with temporary defect in CSF absorption, whereas lumbar peritoneal shunt is required in permanent defect. Repeat ETV is recommended if the stoma is blocked. ETV should be considered as treatment of choice in chronic phase of the disease in obstructive hydrocephalus.

Current and future practices in surgical retraction

Retraction of tissues and anatomical structures is an essential component of all forms of surgery. The means by which operative access is gained through retraction are many and diverse. In this article, the various forms of retraction methods currently available are reviewed, with special reference to hand held, self-retaining and compliant techniques. The special challenges posed by laparoscopic surgery are considered and future developments in new retraction techniques are anticipated.

3D preoperative planning in the ER with OsiriX®: when there is no time for neuronavigation

The evaluation of patients in the emergency room department (ER) through more accurate imaging methods such as computed tomography (CT) has revolutionized their assistance in the early 80s. However, despite technical improvements seen during the last decade, surgical planning in the ER has not followed the development of image acquisition methods. The authors present their experience with DICOM image processing as a navigation method in the ER. The authors present 18 patients treated in the Emergency Department of the Hospital das Clínicas of the University of Sao Paulo. All patients were submitted to volumetric CT. We present patients with epidural hematomas, acute/subacute subdural hematomas and contusional hematomas. Using a specific program to analyze images in DICOM format (OsiriX^®), the authors performed the appropriate surgical planning. The use of 3D surgical planning made it possible to perform procedures more accurately and less invasively, enabling better postoperative outcomes. All sorts of neurosurgical emergency pathologies can be treated appropriately with no waste of time. The three-dimensional processing of images in the preoperative evaluation is easy and possible even within the emergency care. It should be used as a tool to reduce the surgical trauma and it may dispense methods of navigation in many cases.

Endoscopic endonasal trans-sphenoid surgery of pituitary adenoma

Endoscopic endonasal trans-sphenoid surgery (EETS) is increasingly used for pituitary lesions. Pre-operative CT and MRI scans and peroperative endoscopic visualization can provide useful anatomical information. EETS is indicated in sellar, suprasellar, intraventricular, retro-infundibular, and invasive tumors. Recurrent and residual lesions, pituitary apoplexy and empty sella syndrome can be managed by EETS. Modern neuronavigation techniques, ultrasonic aspirators, ultrasonic bone curette can add to the safety. The binostril approach provides a wider working area. High definition camera is much superior to three-chip camera. Most of the recent reports favor EETS in terms of safety, quality of life and tumor resection, hospital stay, better endocrinological, and visual outcome as compared to the microscopic technique. Nasal symptoms, blood loss, operating time are less in EETS. Various naso-septal flaps and other techniques of CSF leak repair could help reduce complications. Complications can be further reduced after achieving the learning curve, good understanding of limitations with proper patient selection. Use of neuronavigation, proper post-operative care of endocrine function, establishing pituitary center of excellence and more focused residency and endoscopic fellowship training could improve results. The faster and safe transition from microscopic to EETS can be done by the team concept of neurosurgeon/otolaryngologist, attending hands on cadaveric dissection, practice on models, and observation of live surgeries. Conversion to a microscopic or endoscopic-assisted approach may be required in selected patients. Multi-modality treatment could be required in giant and invasive tumors. EETS appears to be a better surgical option in most pituitary adenoma.

Endoscopic third ventriculostomy

Endoscopic third ventriculostomy (ETV) is considered as a treatment of choice for obstructive hydrocephalus. It is indicated in hydrocephalus secondary to congenital aqueductal stenosis, posterior third ventricle tumor, cerebellar infarct, Dandy-Walker malformation, vein of Galen aneurism, syringomyelia with or without Chiari malformation type I, intraventricular hematoma, post infective, normal pressure hydrocephalus, myelomeningocele, multiloculated hydrocephalus, encephalocele, posterior fossa tumor and craniosynostosis. It is also indicated in block shunt or slit ventricle syndrome. Proper Pre-operative imaging for detailed assessment of the posterior communicating arteries distance from mid line, presence or absence of Liliequist membrane or other membranes, located in the prepontine cistern is useful. Measurement of lumbar elastance and resistance can predict patency of cranial subarachnoid space and complex hydrocephalus, which decides an ultimate outcome. Water jet dissection is an effective technique of ETV in thick floor. Ultrasonic contact probe can be useful in selected patients. Intra-operative ventriculo-stomography could help in confirming the adequacy of endoscopic procedure, thereby facilitating the need for shunt. Intraoperative observations of the patent aqueduct and prepontine cistern scarring are predictors of the risk of ETV failure. Such patients may be considered for shunt surgery. Magnetic resonance ventriculography and cine phase contrast magnetic resonance imaging are effective in assessing subarachnoid space and stoma patency after ETV. Proper case selection, post-operative care including monitoring of ICP and need for external ventricular drain, repeated lumbar puncture and CSF drainage, Ommaya reservoir in selected patients could help to increase success rate and reduce complications. Most of the complications develop in an early post-operative, but fatal complications can develop late which indicate an importance of long term follow up.