Neuroendoscopy experience in Basrah

In the last decade the endoscope became one of the most important neurosurgical tools, its use increasing with time and gaining popularity. Since May 2005, forty six neuroendoscopy procedures were performed in two hospitals in Basrah, 34 were Endoscopic third ventriculostomies (ETV) to treat hydrocephalus, three arachnoids cyst fenestrations, three ventricular tumor biopsies, and one operation to remove third ventricle tumor partially that already biopsied, three colloid cyst removed and one septotomy to treat encysted hydrocephalus, One case of craniopharyngioma had catheter implanted via the endoscope. The patients’ age ranged from 3 weeks to 70 years, However of the patients who had ETV, 37% (11/34) were younger than one year age. Over one week to twenty months (mean follow up period were 11 months), During that time and for patients who had ETV symptoms of raised intracranial pressure that necessitated a shunt define the failure of treatment, That encountered in two patients , both were younger than one year age. Although time of follow up was rather short, the success rate was 100% for patients older than one year of age who had definite obstructive hydrocephalus. ETV has become the treatment of choice for certain pediatric and adult hydrocephalic conditions. Saving patients from shunt dependence and complications improving the outcomes and avoiding subsequent morbidity and mortality. Introduction euroendoscopy started early in the twentieth century, But endoscopy didn’t role in neurosurgery as wide as it did in other specialities, mainly because of the need for more sophisticated instruments, which was available only in the last couple decades. The Neuroendoscope’s role became essential for the management of many neurosurgical cases and the use of extracranial shunt became an old treatment for hydrocephalus with its many complications. By using the endoscope, management of many untreatable intraventricular lesions became a routine neurosurgical procedure. Third ventriculostomy adopted to replace the traditional treatment by V-P shunt for many cases in our practice and up to date (Feb 2007) 34 patients were treated, Further twelve Endoscopic procedures were performed for different intraventricular pathologies. This article reviews those cases, the indications, procedures performed, their outcome and complications encountered. Endoscopic Third Ventriculostomy: Ventriculostomy was one of the oldest treatments for hydrocephalus 1 ; Dandy was the first who described this procedure in 1922, but the first successful procedure were performed by William Mixter by using a urethroscope in 1923 2 . At that time the endoscope used had poor magnification and illumination which made neuroN Neuroendoscopy Khalid N Mayah Bas J Surg, March, 13, 2007 endoscopy difficult and unreliable. In 1952, the shunt was introduced as a simple and reliable treatment for hydrocephalus, which ends the early era of the neuroendoscopy. The advances in endoscope technologies and the high rate of shunt failure and complications promoted neurosurgeons to review this old treatment for hydrocephalus (ETV). After 1990, many series were published with variable success rates for ETV that ranged from 55-90% 3 . The rationale for Endoscope Third


Introduction
euroendoscopy started early in the twentieth century, But endoscopy didn't role in neurosurgery as wide as it did in other specialities, mainly because of the need for more sophisticated instruments, which was available only in the last couple decades.The Neuroendoscope's role became essential for the management of many neurosurgical cases and the use of extracranial shunt became an old treatment for hydrocephalus with its many complications.By using the endoscope, management of many untreatable intraventricular lesions became a routine neurosurgical procedure.Third ventriculostomy adopted to replace the traditional treatment by V-P shunt for many cases in our practice and up to date (Feb 2007) 34 patients were treated, Further twelve Endoscopic procedures were performed for different intraventricular pathologies.This article reviews those cases, the indications, procedures performed, their outcome and complications encountered.

Endoscopic Third Ventriculostomy:
Ventriculostomy was one of the oldest treatments for hydrocephalus 1 ; Dandy was the first who described this procedure in 1922, but the first successful procedure were performed by William Mixter by using a urethroscope in 1923 2 .At that time the endoscope used had poor magnification and illumination which made neuro-N Bas J Surg, March, 13, 2007   endoscopy difficult and unreliable.In 1952, the shunt was introduced as a simple and reliable treatment for hydrocephalus, which ends the early era of the neuroendoscopy.The advances in endoscope technologies and the high rate of shunt failure and complications promoted neurosurgeons to review this old treatment for hydrocephalus (ETV).After 1990, many series were published with variable success rates for ETV that ranged from 55-90% 3 .

The rationale for Endoscope Third Ventriculostomy:
The real advantage of ETV is elimination of the reliance on mechanical shunts with all their limitations (40% of patients required a shunt revision within 2 years of initial shunt placement) 4 , It returns CSF dynamics to essentially normal status in patients with obstructive hydrocephalus, with better long term success rate.There are no low pressure complications as seen with VP shunt and being a short procedure, patient anesthesia and operation time is significantly reduced.Hospital stay is short and overall the procedure is much more economical than a VP shunt.It also avoids infection 5 .There is no abdominal incision and it can be done by local anesthesia in cooperative patients 6 .  .This is a prospective study, all the patients were recorded in electronic data base that includes their clinical records; follow up visits, radiological investigations and in most of them a video of the procedure.The endoscope most commonly was used to manage hydrocephalus (35/46), (ETV) were the procedure performed for all of them except one septotomy to treat unilateral hydrocephalus for shunted female(Fig.1).

ETV colloid cyst tumor biopsy arachnoid cyst other
Fig. 1: distribution of the cases operated by endoscope, ETV was the commonest procedure.

Clinical material (ETV):
Thirty-four patients were submitted for ETV over 21

The procedure (ETV):
Under General anesthesia a right precoronal parasaggittal Burr hole were done , the trochar with stylet inserted into the lateral ventricle, the endoscope inserted and navigated to the foramina Monroe, When the landmarks were identified (two mamilary bodies and area vasculosum) the site of the supposed Bas J Surg, March, 13, 2007   stoma was planned at mid-way between mamilary bodies and infundibular recess in the midline, The stoma was mostly performed and dilated by fogarty catheter Fr.2, sometime blunt biopsy scissor or diathermy probe were used to create the perforation (Fig. 2).Normal Saline irrigation was used profusely and drain was kept patent.Time consumed in the procedure was ranged from 15-50min (mean time 33 min).All patients were admitted for the ICU or observed for 24 hours after surgery.

Results (ETV):
The procedure was done successfully in all the patients except two, in whom an unfavorable anatomy were encountered in the floor of the third ventricle at which time the procedure aborted and shunt implanted.One of them had aqueduct stenosis, while the other had shunt malfunction that was complicated by ventericulitis.In the first group (younger than one year age), 11 patients had successful procedure, 6 of them having Myelomeningocele-associated hydrocephalus, 3 with congenital aqueductal stenosis, and 2 with Dandy-Walker syndrome.During the follow up period two patients aged 3 and 4 months, who had congenital aqueduct stenosis experienced recurrence of the symptoms 4 and 2 months after the procedure respectively and for that shunt were needed.In this group of patients the success rate was 81% (9/11) (Table II

Complications (ETV):
There was no mortality or major morbidity related to the procedure.Five patients developed CSF leak either from the site of burr hole or craniotomy in subsequent surgeries, 3 of them respond well to medical treatment (diuretics), and two for single/couple lumbar punctures (Tab.III).Three patients experienced repeated fits in the early postoperative period that responded well to antiepileptic treatment.One of them though was admitted for that in the ICU for 5 days.

Discussion (ETV):
Since the rediscovery of the ETV in the last decades of last century, the controversies on its indications existed.Variable success rates suggested the differences in benefit according to age/type of hydrocephalus or the pathology related.In this series we considered a patient as candidate for ETV when the CT scan or MRI of the brain showed dilated lateral and third ventricles with small or invisible fourth ventricle, or if there was obstructive pathology.The age was not considered as a contraindication for the procedure.Recent reports support the evidence that the ETV outcome is more related to the cause than the age 7,11,15 , Mehdorn HM et al, In their experience with ETV in infant gave a 10% success rate in communicating hydrocephalus, 100% success in obstructive ones and 50% in meningocele-associated hydrocephalus.
Then concluded that the outcome was related to the cause of hydrocephalus 7 .Although there is some controversy about this age group, some endoscopist still report low success rate in patients of less than 2 years of age yet, they didn't consider the age a contraindication for the procedure 10,15,19 .Many endoscopists report one or two failures to perform the stoma in their series, and some even reported 31% failure rate (15).In two patients the procedure was aborted and a shunt implanted at the same time.That finding further stresses the importance of the learning curve in Neuroendoscopy that is already recognized 3,10,[20][21][22] .The success rate of ETV in the first group ( infants) is 81% (9/11) which is higher than many other reports, but the follow up time still is shorter than most of them 7,12,15,18,19 .Etuis V, et al, reported in analysis of the results in subgroups with different etiologies of hydrocephalus in infants, that the success rate of the procedure was 83% in patients with defined anatomic obstruction 19 .Khan W. Li, et al, reported 89% success rate in patients who had hydrocephalus due to tectal glioma 23 .The success rate of ETV in infants in most of the series ranged from 56% to 89%, although the success rate is higher in selected subgroup [19][20][21][22] .This may reflect the necessity of patients' selection for this treatment.Anyhow the advantage of having more shunted free patients in this age group should not be denied and the decision should consider each patient with his type of hydrocephalus.Shunt failure unfortunately is encountered more in this age group.The decision to select between those two treatments modalities should consider the treatment risks, results for the same subgroup of the patient, and complications.All have to be discussed with the family.The result of 70% failure rate of the shunt over ten years, should be compared with 75 % overall success rate in endoscopic treatment, yet there is no way of predicting which patient will benefit from the procedure 24 .In this series the success rate in patients older than one year age was 100% (17/17), in many larger series this result has been reported 14,16 .Singh D, et al, reported in their series a 100% success rate in 17 adults and children older than two years 14 , although in a series where the follow up period was longer and included different etiologies for raised ICP the success rate was less and ranged from 60-95% [3][4][5]9,11,14,17 . Few articls discussed the benefits of ETV in patients of myelomeningoceleassociated hydrocephalus and their results were variable (50-71%) 24 , those cases represented a large part of our case load (8/34).The six patients who were followed up are still shunt-free.Many authors studied the benefit of ETV in patients who have malfunctioning shunt and most concluded that it had high success rate 3,5,14,24 .ETV has been reported to have a 76.7 to 77% success rate in those patients [25][26][27] . Inthis series all four patients who presented with shunt malfunction had symptomatic relief after ETV, two of them regained consciousness one day after the procedure and the result is highly encouraging of adopting ETV rather than shunt-revision for patients who presented with shunt malfunction.All eight patients who had posterior fossa tumor and hydrocephalus continued to be shunt-free before and after their surgery for tumor removal.Many articles reported high success rate in this group [28][29][30][31][32][33][34][35][36] .Morelli D, et al, reported 81% success rate in his management for 22 patients 34 .It is well known that the radiological improvements after ETV are less than that following shunt.As the liquor is maintained in the same physiological space, the ventricle will not shrink as in patients who have functioning shunts.Nowoslawska E, et al, studied the ventricle size and head enlargement after ETV and compared the finding with patients who had shunts and concluded that patients treated with ETV had larger ventricle and head circumference and that it was not related to their clinical improvement 16 , a belief shared by many other authors 3,5,8,16.In this series, post treatment scan were done for 14 of 34 patients and were preserved until clinical suspicion of malfunction stoma encountered in others, in those 14 cases the ventricle size were smaller than before treatment and there were no periventricular oedema. Unfortuately cine phase contrast (MRI) study that can define CSF flow in the stoma is not available in our radiological centers yet; it can be useful even to define aqueduct stenosis 36 .Many authors investigate their patients by CT scan or MRI, and depend Bas J Surg, March, 13, 2007   on the rule of dilated lateral and third ventricles and small fourth one to define the obstructive nature of hydrocephalus 4,5,7 .The incidence of complications with ETV has been reported in many large series ranging from 0 to 43% 3,4,9,[23][24][25][26][27][28][29][30][31] , the overall rate of complications encountered is 23%.No patient suffered permanent disability or morbidity and no procedure-related mortality were reported.The complications included three patients who had fit after the procedure, that were responded well to antiepileptic treatments and another five patients who had CSF leak that were complicate their surgery for removing the posterior fossa tumors or from the site of burr hole itself, however three of them respond to diuretics treatment and two to L3-4 lumbar punctures.There is no report of similar complications in many series that discussed ETV complications, although literatures on ETV describes various procedurerelated complications that we did not report in our series, such complications include, basilar artery injury 8 , endocrinopathy caused by hypothalamic or pituitary stalk injury, which typically manifests as diabetes insipidus 3 , cardiac arrhythmia 12,23,32 , postoperative infections 37,38 , subdural haematoma and subglial abscess 39 .

Endoscopic procedures Other than ETV:
Tumor biopsy: Three patients had Endoscopic procedures to biopsy their intraventricular tumors, two of them were in the lateral ventricle and one was in the third ventricle.The procedures were done successfully in all of them and the result of the histopathology was astrocytoma grade II, ependymoma and craniopharyngioma (Fig. 3).All three patients had a shunt implanted at the same session.One of them was submitted for another endoscopic procedure to remove the tumor later on.Three patients had endoscopic surgery to remove colloid cysts.Their ages were ranged from 34-46 years, all of them had hydrocephalus and symptoms related to it.The procedure time ranged from 90-130 min.All had MRI scan postoperatively that proved total removal and relief of hydrocephalus and all were improved clinically (Fig. 4), most authors reported similar results 39,40,41 .In most of the series, 1-7 cases of colloid cysts reported.The lesion, which is rare, is treated by different modalities.Shunt was the oldest one, and is mostly abounded, stereotactic aspiration associated with high recurrence rate 42,43 and microscopically open surgery had high morbidity rate.Lastly the endoscopic removal proved to yield low recurrence and morbidity rates; it should be suggested as the therapy of first choice 42 .

Arachnoid cyst:
One patient of 12 years old and two infants were operated on to fenestrate an intraventricular arachnoid cyst.The procedure was done successfully in all of them, two were well in the follow-up period, while one infant who had a shunt implanted in the same session developed severe dyspnoea and abdominal distension, which may be explained by shunt overdrainage and died two days post operatively.The overall success rate of endoscopically treated arachnoid cysts in a larger series was 70% 37 .Neuroendoscopy is a safe and effective treatment option for arachnoid cysts and should be seriously considered as the initial therapy 41 .
Others: One patient was operated on to remove his third ventricle ependymoma and had partial removal.There was no morbidity related to surgery and discharged 4 days after the procedure.(Fig.5) A patient who had craniopharyngioma occupying the third ventricle had catheter placement through the endoscope and a reservoir implanted to aspirate the fluid.She had CSF leak that respond to diuretic treatments.The cyst get smaller and submitted to radio surgery treatment (Fig. 6).Another patient with craniopharyngioma who had a right side shunt done two years ago presented with headache her MRI scan shows dilated left ventricle and the craniopharyngioma obstructing the foramen Monroe.Septotomy was done for her and she was saved another shunt (Fig. 7).

Conclusion
ETV is a logical alternative to the external divertional procedure (V-P shunt).The result is better in patients with more than one year of age who have definite obstruction.It can be useful in patients who have myelomeningocele-associated hydrocephalus.Patients who have shunt malfunction can be a candidate for the procedure to be shunting independent.Fits are expected in the early post operative period, so all patients should have post operative monitoring and the need for prophylactic antiepileptic should be investigated.Neuroendoscope is ideal to treat colloid cysts, arachnoid cysts and to biopsy intraventricular tumors.We believe that, as a result of its low morbidity the indications for endoscopy will continue to be extended.I acknowledge the efforts of Prof.

Fig. 2 :
Fig.2: A-Site of the precoronal parasaggittal burr hole.B-The endoscope navigated to the foramen Monroe and to the floor of the third ventricle.C-The perforation of the floor and dilatation using Fogarty catheter, two mamilary bodies below.

Fig. 3 :
Fig. 3: MRI scan before (left) and 3 months after ETV (right), The ventricle size is smaller and there is no per ventricular oedema in the post treatment scan.

Fig. 4 :
Fig.4: Colloid cyst A-MRI before treatment the cyst in the roof of the third ventricle onroe B-The endoscopic view shows the cyst obstructing the foramena Monroe, the catheter first used to aspirate the colloid material C-The MRI in the third post operative day, the cyst removed totally.
Safwan A. Taha, CABS for his great support in writing this article.Prof. Vance O. Gardner, M.D., Orthopedic Specialty Institute executive director, Michael G Muhonen, M.D. Pediatric Neurological Surgery, Juliana Ditty (Global Operation and Giving Children hope), Mr. Raymond N. Joekel, who worked together to help me achieving the Neuroendoscopy training in California.

Table II :
).In the second group (more than one year of age), 21 patients had successful procedure (21/23), 9 of them had hydrocephalus due to posterior fossa tumor , 5 due to shunt malfunction, 2 due to posterior third ventricle mass, 2 acquired aqueduct stenosis, 2 congenital aqueduct stenosis, 2 were myelomeningocele-associated and one patient has normal pressure hydrocephalus.The procedures success and out come in relation to the age.

Table III :
The procedure related complications in relation to pathology or type of hydrocephalus Bas J Surg, March,13, 2007