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Complications of Endoscopic Third Ventriculostomy
Peer-Review Reports
Complications of Endoscopic Third Ventriculostomy Triantafyllos Bouras and Spyros Sgouros
Key words 䡲 Endoscopic third ventriculostomy 䡲 Fenestration 䡲 Hydrocephalus 䡲 Neuroendoscopy Abbreviations and Acronyms CSF: Cerebrospinal fluid ETV: Endoscopic third ventriculostomy Department of Neurosurgery, Attikon University Hospital, Athens, Greece To whom correspondence should be addressed: Spyros Sgouros, M.D. [E-mail: [email protected]] Citation: World Neurosurg. (2013) 79, 2S:S22.e9-S22.e12. DOI: 10.1016/j.wneu.2012.02.014 Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com 1878-8750/$ - see front matter © 2013 Elsevier Inc. All rights reserved.
INTRODUCTION Endoscopic third ventriculostomy (ETV) has been established in the last decade as the optimum treatment for most forms of obstructive hydrocephalus. Diverting cerebrospinal fluid (CSF) from the ventricles without the use of any foreign material that is liable to have a future malfunction renders this method preferable to ventriculoperitoneal shunting (10, 19). Nevertheless, it is now accepted that the success of ETV is related to the ultimate cause of hydrocephalus, differing widely between the various pathologies underlying hydrocephalus. Obstructive hydrocephalus related to aqueductal stenosis (15) and to tumors of the posterior fossa (14, 23) is more effectively treated by ETV. Pathologies such as meningomyelocele, Chiari I or II malformation, Dandy-Walker malformation, neonatal intraventricular hemorrhage, and central nervous system infections often cause hydrocephalus, whose eligibility for ETV treatment is still a matter of debate (1, 2, 11, 30). However, many specialists in neuroendoscopy prefer performing an ETV as the first-choice treatment for these patients, aiming to capitalize on the advantages of this method compared with the placement
䡲 BACKGROUND: The treatment of choice for several types of obstructive hydrocephalus is endoscopic third ventriculostomy (ETV). However, in certain cases ETV is not clearly superior to shunt placement, and a question of choice arises. Apart from the possibility of success in each case, knowledge of complication rates is of major importance as well. 䡲 MATERIAL: Several series of ETVs have been published by various specialized centers. The reported overall complication rate is usually between 5% and 15%, and related permanent morbidity lower than 3%. The reported mortality of ETV is lower than 1%. 䡲 RESULTS: The most frequent intraoperative complications of ETV are hemorrhage (the most severe being due to basilar rupture) and injury of neural structures. In the immediate postoperative period, hematomas, infections, and cerebrospinal fluid leaks may present. Morbidity can be neurological and/or hormonal. Systemic complications are related more to the patient’s general status and less to the procedure itself. Late sudden deterioration, leading as a rule to a patient’s death, has been reported. Its incidence is not exactly known, but probably is lower than 0.1%. Nevertheless, the severity of this complication necessitates alertness and informing the patient. 䡲 CONCLUSIONS: The complication rate of ETV is low, and rarely is a reason for choosing shunt placement instead. However, as a method it requires considerable experience, and several studies report a relation of experience not only with success rates but also with complication avoidance.
of a valve, which can be used in cases of ETV failure (22). Apart from the underlying pathology, the patient’s age is of major importance concerning the expected possibility of success, because ETV performed on patients younger than 6 months has been reported to have higher failure rates (17, 25) and is currently the subject of the investigation of the International Infant Hydrocephalus Study. The decision-making process regarding the choice of the best treatment for hydrocephalus in each patient includes not only the knowledge of the success rate that corresponds to each case, but also the possibility of major complications, important morbidity, or even mortality. The complications of ETV can be categorized into the following groups: (A) intraoperative incidents, (B) immediate postoperative complications,
WORLD NEUROSURGERY 79 [2S]: S22.e9-S22.e12, FEBRUARY 2013
and (C) late events. Each complication can be the cause of morbidity or mortality, or may be overcome without having any clinical effect. In the case of ETV, morbidity is mainly of 2 types, either neurological or hormonal, and can be transient or permanent.
OVERALL COMPLICATION RATE There is a certain variation regarding reported complication rates of ETV among different centers. This variation is up to a point due to methodological issues, with each center identifying different postoperative incidents as complications due to the lack of universally accepted criteria. However, it is highly probable that there are also true differences among centers, and it is generally accepted that the complication rate is related to the experience of each cen-
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PEER-REVIEW REPORTS TRIANTAFYLLOS BOURAS AND SPYROS SGOUROS
ter and of each surgeon individually in the procedure (28). Hence, reported rates vary from 0% in series reporting only major complications (12, 29) to 31.2% in series reporting all minor incidents related to the operation (for example, fever) (3). Most series, however, report rates between 5% and 15% (1, 6, 7, 10, 16, 18, 26, 28, 31), and in a meta-analysis we performed recently, the overall complication rate was 8.5% (5).
INTRAOPERATIVE INCIDENTS The most frequent intraoperative incident concerns hemorrhage of various extents. This complication may take place during several steps of ETV. Bleeding may occur immediately after the entrance of the endoscope in the lateral ventricle, caused by rupture of small cortical, parenchymal, or ependymal vessels. This type of hemorrhage is almost never difficult to deal with. Bleeding may occur during the passage of the endoscope in the third ventricle through the foramen of Monro. This hemorrhage may be more severe, but most importantly, it might represent injury of important veins, such as the thalamostriate and the septal vein, which if they thrombose in the attempt for hemostasis, will lead to venous infarct in the basal ganglia. During the opening of the stoma on the floor of the third ventricle, bleeding of minor vessels is not rare. In this case, the hemorrhage usually ceases with irrigation, and as a rule, more drastic measures are not necessary. Small vessels of the suprachiasmatic cistern may also rupture immediately after the formation of the ventriculostomy. The most feared intraoperative complication of ETV is rupture of the basilar artery, which may occur in this step of the operation as well. The danger for this arises from the fact that the stoma on the floor of the third ventricle is by necessity in proximity to the basilar bifurcation. To avoid this complication, the surgeon must choose carefully the location of the ventriculostomy. This is easier in young patients with very large ventricles, when the basilar artery is visible through the thinned floor of the third ventricle. On the contrary, in older patients or if there have been previous episodes of CSF infection (e.g., shunt infection), the floor may be thickened and the position of the basilar artery more difficult to identify. If rupture of the basilar artery occurs, the
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COMPLICATIONS OF ETV
operation must be abandoned and the endoscope should be left in place to deliver irrigation at the site of the vascular injury. Usually the hemorrhage stops after 10 to 15 minutes of irrigation. The endoscope then is removed and an external ventricular drain is placed and kept in place until the CSF clears. Reported rates of intraoperative bleeding vary from 0 to 8.5% (1, 2, 4, 7, 13, 27). A generally accepted rate of considerable hemorrhagic incidents during ETV is 4%. Basilar rupture is reported in ⬍0.2% of cases (1, 4, 22, 25). Abortion of the procedure due to intraoperative hemorrhage is not rare, but is required in ⬍1% of ETVs (2, 7, 14, 26, 31). Intraoperative injury of neural structures is more rarely reported (3, 11, 16, 18). However, judging by the reported rates of related neurological morbidity, it occurs more often than appreciated. Injury affects, in descending order of frequency, the oculomotor nerve (immediately after the entrance to the cistern), the fornix (during passing through the foramen of Monro), the thalamus, and the midbrain (caused by an abrupt entrance of the endoscope in the lateral ventricle). The reported rate of each one of these events is ⬍0.1%. Traumatization of the hypothalamus usually occurs in cases of eccentric stoma realization, and is revealed postoperatively by various hormonal disorders. Finally, anesthetic events during ETV are not rare, but are often of a benign character. Usually they take place during dilatation of the stoma when a balloon is used, which can apply indirect pressure on the basilar artery and interfere with the blood supply of the brain stem, leading to arterial pulse irregularities and cardiac dysrhythmia. The need to abandon the procedure due to severe bradycardia or/and hypotension takes place in ⬍0.2% of the operations (16).
IMMEDIATE POSTOPERATIVE COMPLICATIONS The most frequent postoperative complication of ETV is CSF leak from the skin incision (7, 18, 28, 31). This can be provoked by the increased intraventricular pressure that often exists immediately postoperatively, even in cases of successful ETVs, although not uncommonly, poor wound closure accounts for the CSF leak. However, occurrence of CSF leak is often the first sign of
early ETV failure. In any case, CSF leak is generally treated effectively with resuturing of the skin incision, and occasionally serial lumbar punctures when increased intracranial pressure is suspected. Its reported rate ranges between 0% and 5.2%, with a calculated mean rate of 1.7%, according to our meta-analysis (5). Infectious complications are reported in similar rates, commonly related to CSF leak, although not always. They occur within the immediate postoperative period and are mainly meningitis (1, 5, 7, 18) or ventriculitis (25, 31), which rarely evolve to sepsis (18). Reported rates vary from 0% to 6.1%. Targeted antibiotic treatment is usually effective. Other infectious disorders, such as pulmonary and urinary infections, are also reported in some studies, but they cannot be considered as ETV-specific complications and they are most likely related to the patient’s preoperative general status (7, 16). As a rule, a patient who has undergone an otherwise uncomplicated ETV is not likely to suffer from a systemic infection. All types of intracranial hematomas may occur after an ETV. However, these incidents are not frequent; overall hemorrhagic complications of the postoperative period occur in ⬍1% of the cases. In some cases, an intraventricular or subarachnoid hemorrhage may be the result of an intraoperative incident (major uncontrollable bleeding) (5, 23, 28). Nevertheless, in most cases, subdural, intracerebral, and intraventricular hematomas are diagnosed after otherwise uneventful ETVs, as a result of the rupture of a cortical, parenchymal, or ependymal vessel, respectively, leading to underestimated bleeding (8, 15, 16, 18). Epidural hematomas are rarely reported, and require a reoperation. The treatment of a subdural hematoma can be rather complicated in the context of a significantly lowered intraventricular pressure. Finally, subdural hygromas are significantly less frequent than after ventriculoperitoneal shunting. However, when they occur, they require careful treatment and sometimes prove difficult to deal with (21).
MORBIDITY Transient postoperative neurologic deficits are reported to various rates. They include
WORLD NEUROSURGERY, DOI:10.1016/j.wneu.2012.02.014
PEER-REVIEW REPORTS TRIANTAFYLLOS BOURAS AND SPYROS SGOUROS
hemiparesis, gaze palsy, various levels of decreased consciousness, memory disorders, seizures, and sporadic cases of akinetic mutism. Permanent neurological morbidity is estimated to occur in 1.2% of patients who have undergone an ETV. Hemiparesis, which is either the result of intraoperative thalamic (or thalamostriate vein or head of the caudate) trauma or due to a postoperative hematoma, occurs in 0.4% of the cases (16, 4, 24). Even rarer are permanent gaze palsy (due to trauma of the oculomotor nerve, if the stoma is off the midline of the floor of the third ventricle), memory disorders (as a result of forniceal injury) and consciousness disorders (1, 3, 4, 14, 22, 25). Hormonal morbidity includes mainly transient diabetes insipidus of hypothalamic origin. In 0.5% of the patients, diabetes insipidus is permanent (3, 18, 22, 28). Weight gain is also a result of hypothalamic injury, and occurs even less often (18). Sporadic cases of precocious puberty have been reported (18). The overall rate of permanent hormonal morbidity is ⬍1%. In total, permanent morbidity of ETV has been estimated at 2.4% (5). Finally, systemic morbidity related to ETV includes various cardiorespiratory events (bradycardia, hypotension) mainly with a transient character, electrolytic disorders such as hyponatremia, fever, urinary retention, deep vein thrombosis, and pulmonary embolism, mainly in elderly patients (7, 16).
MORTALITY Various studies cite low mortality rates related to ETV. Many of the deaths reported, however, are not attributed directly to the procedure, but come as a result of tumor progression (26), in patients with tumor related hydrocephalus, or as systemic complications (pneumonia, renal failure) (31). A mortality rate of 0.3% is generally accepted. The most frequent ETV-related causes of immediate postoperative death are severe neurological deficits (related to hemorrhagic incidents or neural injuries) and sepsis (1, 16, 18,). In the meta-analysis we performed, no intraoperative death was reported. The mortality rate of basilar rupture was 50% (5).
COMPLICATIONS OF ETV
SUDDEN LATE DETERIORATION POTENTIALLY LEADING TO DEATH Sporadic cases of late sudden death of children who have previously undergone otherwise uneventful ETVs have been reported. Until now, case and short series reports of such incidents have not presented a valid estimation of the possibility of occurrence (4, 24). The 2 most important studies report 16 cases in total, collected from various centers worldwide; according to them, a rapid and often lethal deterioration could occur from 5 weeks to 7.8 years after ETV, and the finding is almost always stoma occlusion (9, 20). In the meta-analysis we performed, the rate of this lethal complication was 0.07% (5). Nevertheless, given the possibly long delay until its occurrence, sudden death may have been underestimated in that study, its mean follow-up being 26 months. As a conclusion, this complication is very rare; however it should always be kept in mind, and patients and relatives should be informed about this possibility.
CONCLUSIONS The immediate complication rate of ETV is comparable to that of ventriculoperitoneal shunting. However, in the long term, shunts are susceptible to several disorders leading to dysfunction and the need for replacement (with subsequent risk of infection). The incidence of late sudden deterioration after ETV is not negligible, but is not a sufficient contraindication for an otherwise safe and efficient method for the treatment of obstructive hydrocephalus (10, 19, 24). Several studies imply that there is a strong relationship between the complication rate of ETV and the operator’s experience; therefore, it is necessary that that this procedure is performed by experts in specialized centers. This strategy is necessary for achieving the abovementioned low complication rates and a high success rate for control of the hydrocephalus by ETV alone (1, 24).
2. Baykan N, Isbir O, Gercek A, Dagcnar A, Ozek MM: Ten years of experience with pediatric neuroendoscopic third ventriculostomy: features and perioperative complications of 210 cases. J Neurosurg Anesthesiol 17:33-37, 2005. 3. Beems T, Grotenhuis JA: Is the success rate of endoscopic third ventriculostomy age-dependent? An analysis of the results of endoscopic third ventriculostomy in young children. Childs Nerv Syst 18:605608, 2002. 4. Bilginer B, Oguz KK, Akalan N: Endoscopic third ventriculostomy for malfunction in previously shunted infants. Childs Nerv Syst 25:683-688, 2009. 5. Bouras T, Sgouros S: Complications of endoscopic third ventriculostomy in children. A meta-analysis. J Neurosurg Pediatr 7:643-649, 2011. 6. Brockmeyer D, Abtin K, Carey L, Walker ML: Endoscopic third ventriculostomy: an outcome analysis. Pediatr Neurosurg 28:236-240, 1998. 7. de Ribaupierre S, Rilliet B, Vernet O, Regli L, Villemure JG: Third ventriculostomy vs ventriculoperitoneal shunt in pediatric obstructive hydrocephalus: results from a Swiss series and literature review. Childs Nerv Syst 23:527-533, 2007. 8. Drake J, Chumas P, Kestle J, Pierre-Kahn A, Vinchon M, Brown J, Pollack IF, Arai H: Late rapid deterioration after endoscopic third ventriculostomy: additional cases and review of the literature. J Neurosurg 105(suppl):118-126, 2006. 9. Drake JM, Kulkarni AV, Kestle J: Endoscopic third ventriculostomy versus ventriculoperitoneal shunt in pediatric patients: a decision analysis. Childs Nerv Syst 25:467-472, 2009. 10. Dusick JR, McArthur DL, Bergsneider M: Success and complication rates of endoscopic third ventriculostomy for adult hydrocephalus: a series of 108 patients. Surg Neurol 69:5-15, 2008. 11. Egger D, Balmer B, Altermatt S, Meuli M: Third ventriculostomy in a single pediatric surgical unit. Childs Nerv Syst 26:93-99, 2010. 12. Ersahin Y, Arslan D: Complications of endoscopic third ventriculostomy. Childs Nerv Syst 24:943-948, 2008. 13. Gangemi M, Maiuri F, Buonamassa S, Colella G, de Divitiis E: Endoscopic third ventriculostomy in idiopathic normal pressure hydrocephalus. Neurosurgery 55:129-134 [discussion 134], 2004. 14. Garton HJ, Kestle JR, Cochrane DD, Steinbok P: A cost-effectiveness analysis of endoscopic third ventriculostomy. Neurosurgery 51:69-77 [discussion 77-78], 2002. 15. Gorayeb RP, Cavalheiro S, Zymberg ST: Endoscopic third ventriculostomy in children younger than 1 year of age. J Neurosurg 100(suppl):427-429, 2004.
REFERENCES 1. Amini A, Schmidt RH: Endoscopic third ventriculostomy in a series of 36 adult patients. Neurosurg Focus 19:E9, 2005.
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16. Grunert P, Charalampaki P, Hopf N, Filippi R: The role of third ventriculostomy in the management of obstructive hydrocephalus. Minim Invasive Neurosurg 46:16-21, 2003.
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17. Hader WJ, Drake J, Cochrane D, Sparrow O, Johnson ES, Kestle J: Death after late failure of third ventriculostomy in children. Report of three cases. J Neurosurg 97:211-215, 2002. 18. Hader WJ, Walker RL, Myles ST, Hamilton M: Complications of endoscopic third ventriculostomy in previously shunted patients. Neurosurgery 63(suppl 1):ONS168- ONS174 [discussion ONS74- ONS75], 2008. 19. Hailong F, Guangfu H, Haibin T, Hong P, Yong C, Weidong L, Dongdong Z: Endoscopic third ventriculostomy in the management of communicating hydrocephalus: a preliminary study. J Neurosurg 109: 923-930, 2008. 20. Hopf NJ, Grunert P, Fries G, Resch KD, Perneczky A: Endoscopic third ventriculostomy: outcome analysis of 100 consecutive procedures. Neurosurgery 44:795-804 [discussion 804-806], 1999.
COMPLICATIONS OF ETV
tion of postoperative neuroimaging. Childs Nerv Syst 16:161-168 [discussion 169], 2000.
communicating hydrocephalus. Acta Neurochir (Wien) 147:377-382 [discussion 382], 2005.
23. Kurschel S, Ono S, Oi S: Risk reduction of subdural collections following endoscopic third ventriculostomy. Childs Nerv Syst 23:521-526, 2007.
29. Scarrow AM, Levy EI, Pascucci L, Albright AL: Outcome analysis of endoscopic III ventriculostomy. Childs Nerv Syst 16:442-444 [discussion 445], 2000.
24. Navarro R, Gil-Parra R, Reitman AJ, Olavarria G, Grant JA, Tomita T: Endoscopic third ventriculostomy in children: early and late complications and their avoidance. Childs Nerv Syst 22:506-513, 2006.
30. Schroeder HW, Niendorf WR, Gaab MR: Complications of endoscopic third ventriculostomy. J Neurosurg 96:1032-1040, 2002.
25. Ogiwara H, Dipatri A Jr, Alden TD, Bowman RM, Tomita T: Endoscopic third ventriculostomy for obstructive hydrocephalus in children younger than 6 months of age. Childs Nerv Syst 26:343-347, 2010. 26. Ray P, Jallo GI, Kim RY, Kim BS, Wilson S, Kothbauer K, Abbott R: Endoscopic third ventriculostomy for tumor-related hydrocephalus in a pediatric population. Neurosurg Focus 19:E8, 2005.
21. Kadrian D, van Gelder J, Florida D, Jones R, Vonau M, Teo C, Stening W, Kwok B: Long-term reliability of endoscopic third ventriculostomy. Neurosurgery 56:1271-1278 [discussion 1278], 2005.
27. Ruggiero C, Cinalli G, Spennato P, Aliberti F, Cianciulli E, Trischitta V, Maggi G: Endoscopic third ventriculostomy in the treatment of hydrocephalus in posterior fossa tumors in children. Childs Nerv Syst 20:828-833, 2004.
22. Kim SK, Wang KC, Cho BK: Surgical outcome of pediatric hydrocephalus treated by endoscopic III ventriculostomy: prognostic factors and interpreta-
28. Santamarta D, Diaz Alvarez A, Goncalves JM, Hernandez J: Outcome of endoscopic third ventriculostomy. Results from an unselected series with non-
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31. van Beijnum J, Hanlo PW, Fischer K, Majidpour MM, Kortekaas MF, Verdaasdonk RM, Vandertop WP: Laser-assisted endoscopic third ventriculostomy: long-term results in a series of 202 patients. Neurosurgery 62:437-443 [discussion 443-444], 2008.
Conflict of interest statement: The authors declare that the article content was composed in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Received 18 August 2011; accepted 02 February 2012 Citation: World Neurosurg. (2013) 79, 2S:S22.e9-S22.e12. DOI: 10.1016/j.wneu.2012.02.014 Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com 1878-8750/$ - see front matter © 2013 Elsevier Inc. All rights reserved.
WORLD NEUROSURGERY, DOI:10.1016/j.wneu.2012.02.014
Complications of Endoscopic Third Ventriculostomy Triantafyllos Bouras and Spyros Sgouros
Key words 䡲 Endoscopic third ventriculostomy 䡲 Fenestration 䡲 Hydrocephalus 䡲 Neuroendoscopy Abbreviations and Acronyms CSF: Cerebrospinal fluid ETV: Endoscopic third ventriculostomy Department of Neurosurgery, Attikon University Hospital, Athens, Greece To whom correspondence should be addressed: Spyros Sgouros, M.D. [E-mail: [email protected]] Citation: World Neurosurg. (2013) 79, 2S:S22.e9-S22.e12. DOI: 10.1016/j.wneu.2012.02.014 Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com 1878-8750/$ - see front matter © 2013 Elsevier Inc. All rights reserved.
INTRODUCTION Endoscopic third ventriculostomy (ETV) has been established in the last decade as the optimum treatment for most forms of obstructive hydrocephalus. Diverting cerebrospinal fluid (CSF) from the ventricles without the use of any foreign material that is liable to have a future malfunction renders this method preferable to ventriculoperitoneal shunting (10, 19). Nevertheless, it is now accepted that the success of ETV is related to the ultimate cause of hydrocephalus, differing widely between the various pathologies underlying hydrocephalus. Obstructive hydrocephalus related to aqueductal stenosis (15) and to tumors of the posterior fossa (14, 23) is more effectively treated by ETV. Pathologies such as meningomyelocele, Chiari I or II malformation, Dandy-Walker malformation, neonatal intraventricular hemorrhage, and central nervous system infections often cause hydrocephalus, whose eligibility for ETV treatment is still a matter of debate (1, 2, 11, 30). However, many specialists in neuroendoscopy prefer performing an ETV as the first-choice treatment for these patients, aiming to capitalize on the advantages of this method compared with the placement
䡲 BACKGROUND: The treatment of choice for several types of obstructive hydrocephalus is endoscopic third ventriculostomy (ETV). However, in certain cases ETV is not clearly superior to shunt placement, and a question of choice arises. Apart from the possibility of success in each case, knowledge of complication rates is of major importance as well. 䡲 MATERIAL: Several series of ETVs have been published by various specialized centers. The reported overall complication rate is usually between 5% and 15%, and related permanent morbidity lower than 3%. The reported mortality of ETV is lower than 1%. 䡲 RESULTS: The most frequent intraoperative complications of ETV are hemorrhage (the most severe being due to basilar rupture) and injury of neural structures. In the immediate postoperative period, hematomas, infections, and cerebrospinal fluid leaks may present. Morbidity can be neurological and/or hormonal. Systemic complications are related more to the patient’s general status and less to the procedure itself. Late sudden deterioration, leading as a rule to a patient’s death, has been reported. Its incidence is not exactly known, but probably is lower than 0.1%. Nevertheless, the severity of this complication necessitates alertness and informing the patient. 䡲 CONCLUSIONS: The complication rate of ETV is low, and rarely is a reason for choosing shunt placement instead. However, as a method it requires considerable experience, and several studies report a relation of experience not only with success rates but also with complication avoidance.
of a valve, which can be used in cases of ETV failure (22). Apart from the underlying pathology, the patient’s age is of major importance concerning the expected possibility of success, because ETV performed on patients younger than 6 months has been reported to have higher failure rates (17, 25) and is currently the subject of the investigation of the International Infant Hydrocephalus Study. The decision-making process regarding the choice of the best treatment for hydrocephalus in each patient includes not only the knowledge of the success rate that corresponds to each case, but also the possibility of major complications, important morbidity, or even mortality. The complications of ETV can be categorized into the following groups: (A) intraoperative incidents, (B) immediate postoperative complications,
WORLD NEUROSURGERY 79 [2S]: S22.e9-S22.e12, FEBRUARY 2013
and (C) late events. Each complication can be the cause of morbidity or mortality, or may be overcome without having any clinical effect. In the case of ETV, morbidity is mainly of 2 types, either neurological or hormonal, and can be transient or permanent.
OVERALL COMPLICATION RATE There is a certain variation regarding reported complication rates of ETV among different centers. This variation is up to a point due to methodological issues, with each center identifying different postoperative incidents as complications due to the lack of universally accepted criteria. However, it is highly probable that there are also true differences among centers, and it is generally accepted that the complication rate is related to the experience of each cen-
www.WORLDNEUROSURGERY.org
S22.e9
PEER-REVIEW REPORTS TRIANTAFYLLOS BOURAS AND SPYROS SGOUROS
ter and of each surgeon individually in the procedure (28). Hence, reported rates vary from 0% in series reporting only major complications (12, 29) to 31.2% in series reporting all minor incidents related to the operation (for example, fever) (3). Most series, however, report rates between 5% and 15% (1, 6, 7, 10, 16, 18, 26, 28, 31), and in a meta-analysis we performed recently, the overall complication rate was 8.5% (5).
INTRAOPERATIVE INCIDENTS The most frequent intraoperative incident concerns hemorrhage of various extents. This complication may take place during several steps of ETV. Bleeding may occur immediately after the entrance of the endoscope in the lateral ventricle, caused by rupture of small cortical, parenchymal, or ependymal vessels. This type of hemorrhage is almost never difficult to deal with. Bleeding may occur during the passage of the endoscope in the third ventricle through the foramen of Monro. This hemorrhage may be more severe, but most importantly, it might represent injury of important veins, such as the thalamostriate and the septal vein, which if they thrombose in the attempt for hemostasis, will lead to venous infarct in the basal ganglia. During the opening of the stoma on the floor of the third ventricle, bleeding of minor vessels is not rare. In this case, the hemorrhage usually ceases with irrigation, and as a rule, more drastic measures are not necessary. Small vessels of the suprachiasmatic cistern may also rupture immediately after the formation of the ventriculostomy. The most feared intraoperative complication of ETV is rupture of the basilar artery, which may occur in this step of the operation as well. The danger for this arises from the fact that the stoma on the floor of the third ventricle is by necessity in proximity to the basilar bifurcation. To avoid this complication, the surgeon must choose carefully the location of the ventriculostomy. This is easier in young patients with very large ventricles, when the basilar artery is visible through the thinned floor of the third ventricle. On the contrary, in older patients or if there have been previous episodes of CSF infection (e.g., shunt infection), the floor may be thickened and the position of the basilar artery more difficult to identify. If rupture of the basilar artery occurs, the
S22.e10
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COMPLICATIONS OF ETV
operation must be abandoned and the endoscope should be left in place to deliver irrigation at the site of the vascular injury. Usually the hemorrhage stops after 10 to 15 minutes of irrigation. The endoscope then is removed and an external ventricular drain is placed and kept in place until the CSF clears. Reported rates of intraoperative bleeding vary from 0 to 8.5% (1, 2, 4, 7, 13, 27). A generally accepted rate of considerable hemorrhagic incidents during ETV is 4%. Basilar rupture is reported in ⬍0.2% of cases (1, 4, 22, 25). Abortion of the procedure due to intraoperative hemorrhage is not rare, but is required in ⬍1% of ETVs (2, 7, 14, 26, 31). Intraoperative injury of neural structures is more rarely reported (3, 11, 16, 18). However, judging by the reported rates of related neurological morbidity, it occurs more often than appreciated. Injury affects, in descending order of frequency, the oculomotor nerve (immediately after the entrance to the cistern), the fornix (during passing through the foramen of Monro), the thalamus, and the midbrain (caused by an abrupt entrance of the endoscope in the lateral ventricle). The reported rate of each one of these events is ⬍0.1%. Traumatization of the hypothalamus usually occurs in cases of eccentric stoma realization, and is revealed postoperatively by various hormonal disorders. Finally, anesthetic events during ETV are not rare, but are often of a benign character. Usually they take place during dilatation of the stoma when a balloon is used, which can apply indirect pressure on the basilar artery and interfere with the blood supply of the brain stem, leading to arterial pulse irregularities and cardiac dysrhythmia. The need to abandon the procedure due to severe bradycardia or/and hypotension takes place in ⬍0.2% of the operations (16).
IMMEDIATE POSTOPERATIVE COMPLICATIONS The most frequent postoperative complication of ETV is CSF leak from the skin incision (7, 18, 28, 31). This can be provoked by the increased intraventricular pressure that often exists immediately postoperatively, even in cases of successful ETVs, although not uncommonly, poor wound closure accounts for the CSF leak. However, occurrence of CSF leak is often the first sign of
early ETV failure. In any case, CSF leak is generally treated effectively with resuturing of the skin incision, and occasionally serial lumbar punctures when increased intracranial pressure is suspected. Its reported rate ranges between 0% and 5.2%, with a calculated mean rate of 1.7%, according to our meta-analysis (5). Infectious complications are reported in similar rates, commonly related to CSF leak, although not always. They occur within the immediate postoperative period and are mainly meningitis (1, 5, 7, 18) or ventriculitis (25, 31), which rarely evolve to sepsis (18). Reported rates vary from 0% to 6.1%. Targeted antibiotic treatment is usually effective. Other infectious disorders, such as pulmonary and urinary infections, are also reported in some studies, but they cannot be considered as ETV-specific complications and they are most likely related to the patient’s preoperative general status (7, 16). As a rule, a patient who has undergone an otherwise uncomplicated ETV is not likely to suffer from a systemic infection. All types of intracranial hematomas may occur after an ETV. However, these incidents are not frequent; overall hemorrhagic complications of the postoperative period occur in ⬍1% of the cases. In some cases, an intraventricular or subarachnoid hemorrhage may be the result of an intraoperative incident (major uncontrollable bleeding) (5, 23, 28). Nevertheless, in most cases, subdural, intracerebral, and intraventricular hematomas are diagnosed after otherwise uneventful ETVs, as a result of the rupture of a cortical, parenchymal, or ependymal vessel, respectively, leading to underestimated bleeding (8, 15, 16, 18). Epidural hematomas are rarely reported, and require a reoperation. The treatment of a subdural hematoma can be rather complicated in the context of a significantly lowered intraventricular pressure. Finally, subdural hygromas are significantly less frequent than after ventriculoperitoneal shunting. However, when they occur, they require careful treatment and sometimes prove difficult to deal with (21).
MORBIDITY Transient postoperative neurologic deficits are reported to various rates. They include
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hemiparesis, gaze palsy, various levels of decreased consciousness, memory disorders, seizures, and sporadic cases of akinetic mutism. Permanent neurological morbidity is estimated to occur in 1.2% of patients who have undergone an ETV. Hemiparesis, which is either the result of intraoperative thalamic (or thalamostriate vein or head of the caudate) trauma or due to a postoperative hematoma, occurs in 0.4% of the cases (16, 4, 24). Even rarer are permanent gaze palsy (due to trauma of the oculomotor nerve, if the stoma is off the midline of the floor of the third ventricle), memory disorders (as a result of forniceal injury) and consciousness disorders (1, 3, 4, 14, 22, 25). Hormonal morbidity includes mainly transient diabetes insipidus of hypothalamic origin. In 0.5% of the patients, diabetes insipidus is permanent (3, 18, 22, 28). Weight gain is also a result of hypothalamic injury, and occurs even less often (18). Sporadic cases of precocious puberty have been reported (18). The overall rate of permanent hormonal morbidity is ⬍1%. In total, permanent morbidity of ETV has been estimated at 2.4% (5). Finally, systemic morbidity related to ETV includes various cardiorespiratory events (bradycardia, hypotension) mainly with a transient character, electrolytic disorders such as hyponatremia, fever, urinary retention, deep vein thrombosis, and pulmonary embolism, mainly in elderly patients (7, 16).
MORTALITY Various studies cite low mortality rates related to ETV. Many of the deaths reported, however, are not attributed directly to the procedure, but come as a result of tumor progression (26), in patients with tumor related hydrocephalus, or as systemic complications (pneumonia, renal failure) (31). A mortality rate of 0.3% is generally accepted. The most frequent ETV-related causes of immediate postoperative death are severe neurological deficits (related to hemorrhagic incidents or neural injuries) and sepsis (1, 16, 18,). In the meta-analysis we performed, no intraoperative death was reported. The mortality rate of basilar rupture was 50% (5).
COMPLICATIONS OF ETV
SUDDEN LATE DETERIORATION POTENTIALLY LEADING TO DEATH Sporadic cases of late sudden death of children who have previously undergone otherwise uneventful ETVs have been reported. Until now, case and short series reports of such incidents have not presented a valid estimation of the possibility of occurrence (4, 24). The 2 most important studies report 16 cases in total, collected from various centers worldwide; according to them, a rapid and often lethal deterioration could occur from 5 weeks to 7.8 years after ETV, and the finding is almost always stoma occlusion (9, 20). In the meta-analysis we performed, the rate of this lethal complication was 0.07% (5). Nevertheless, given the possibly long delay until its occurrence, sudden death may have been underestimated in that study, its mean follow-up being 26 months. As a conclusion, this complication is very rare; however it should always be kept in mind, and patients and relatives should be informed about this possibility.
CONCLUSIONS The immediate complication rate of ETV is comparable to that of ventriculoperitoneal shunting. However, in the long term, shunts are susceptible to several disorders leading to dysfunction and the need for replacement (with subsequent risk of infection). The incidence of late sudden deterioration after ETV is not negligible, but is not a sufficient contraindication for an otherwise safe and efficient method for the treatment of obstructive hydrocephalus (10, 19, 24). Several studies imply that there is a strong relationship between the complication rate of ETV and the operator’s experience; therefore, it is necessary that that this procedure is performed by experts in specialized centers. This strategy is necessary for achieving the abovementioned low complication rates and a high success rate for control of the hydrocephalus by ETV alone (1, 24).
2. Baykan N, Isbir O, Gercek A, Dagcnar A, Ozek MM: Ten years of experience with pediatric neuroendoscopic third ventriculostomy: features and perioperative complications of 210 cases. J Neurosurg Anesthesiol 17:33-37, 2005. 3. Beems T, Grotenhuis JA: Is the success rate of endoscopic third ventriculostomy age-dependent? An analysis of the results of endoscopic third ventriculostomy in young children. Childs Nerv Syst 18:605608, 2002. 4. Bilginer B, Oguz KK, Akalan N: Endoscopic third ventriculostomy for malfunction in previously shunted infants. Childs Nerv Syst 25:683-688, 2009. 5. Bouras T, Sgouros S: Complications of endoscopic third ventriculostomy in children. A meta-analysis. J Neurosurg Pediatr 7:643-649, 2011. 6. Brockmeyer D, Abtin K, Carey L, Walker ML: Endoscopic third ventriculostomy: an outcome analysis. Pediatr Neurosurg 28:236-240, 1998. 7. de Ribaupierre S, Rilliet B, Vernet O, Regli L, Villemure JG: Third ventriculostomy vs ventriculoperitoneal shunt in pediatric obstructive hydrocephalus: results from a Swiss series and literature review. Childs Nerv Syst 23:527-533, 2007. 8. Drake J, Chumas P, Kestle J, Pierre-Kahn A, Vinchon M, Brown J, Pollack IF, Arai H: Late rapid deterioration after endoscopic third ventriculostomy: additional cases and review of the literature. J Neurosurg 105(suppl):118-126, 2006. 9. Drake JM, Kulkarni AV, Kestle J: Endoscopic third ventriculostomy versus ventriculoperitoneal shunt in pediatric patients: a decision analysis. Childs Nerv Syst 25:467-472, 2009. 10. Dusick JR, McArthur DL, Bergsneider M: Success and complication rates of endoscopic third ventriculostomy for adult hydrocephalus: a series of 108 patients. Surg Neurol 69:5-15, 2008. 11. Egger D, Balmer B, Altermatt S, Meuli M: Third ventriculostomy in a single pediatric surgical unit. Childs Nerv Syst 26:93-99, 2010. 12. Ersahin Y, Arslan D: Complications of endoscopic third ventriculostomy. Childs Nerv Syst 24:943-948, 2008. 13. Gangemi M, Maiuri F, Buonamassa S, Colella G, de Divitiis E: Endoscopic third ventriculostomy in idiopathic normal pressure hydrocephalus. Neurosurgery 55:129-134 [discussion 134], 2004. 14. Garton HJ, Kestle JR, Cochrane DD, Steinbok P: A cost-effectiveness analysis of endoscopic third ventriculostomy. Neurosurgery 51:69-77 [discussion 77-78], 2002. 15. Gorayeb RP, Cavalheiro S, Zymberg ST: Endoscopic third ventriculostomy in children younger than 1 year of age. J Neurosurg 100(suppl):427-429, 2004.
REFERENCES 1. Amini A, Schmidt RH: Endoscopic third ventriculostomy in a series of 36 adult patients. Neurosurg Focus 19:E9, 2005.
WORLD NEUROSURGERY 79 [2S]: S22.e9-S22.e12, FEBRUARY 2013
16. Grunert P, Charalampaki P, Hopf N, Filippi R: The role of third ventriculostomy in the management of obstructive hydrocephalus. Minim Invasive Neurosurg 46:16-21, 2003.
www.WORLDNEUROSURGERY.org
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PEER-REVIEW REPORTS TRIANTAFYLLOS BOURAS AND SPYROS SGOUROS
17. Hader WJ, Drake J, Cochrane D, Sparrow O, Johnson ES, Kestle J: Death after late failure of third ventriculostomy in children. Report of three cases. J Neurosurg 97:211-215, 2002. 18. Hader WJ, Walker RL, Myles ST, Hamilton M: Complications of endoscopic third ventriculostomy in previously shunted patients. Neurosurgery 63(suppl 1):ONS168- ONS174 [discussion ONS74- ONS75], 2008. 19. Hailong F, Guangfu H, Haibin T, Hong P, Yong C, Weidong L, Dongdong Z: Endoscopic third ventriculostomy in the management of communicating hydrocephalus: a preliminary study. J Neurosurg 109: 923-930, 2008. 20. Hopf NJ, Grunert P, Fries G, Resch KD, Perneczky A: Endoscopic third ventriculostomy: outcome analysis of 100 consecutive procedures. Neurosurgery 44:795-804 [discussion 804-806], 1999.
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tion of postoperative neuroimaging. Childs Nerv Syst 16:161-168 [discussion 169], 2000.
communicating hydrocephalus. Acta Neurochir (Wien) 147:377-382 [discussion 382], 2005.
23. Kurschel S, Ono S, Oi S: Risk reduction of subdural collections following endoscopic third ventriculostomy. Childs Nerv Syst 23:521-526, 2007.
29. Scarrow AM, Levy EI, Pascucci L, Albright AL: Outcome analysis of endoscopic III ventriculostomy. Childs Nerv Syst 16:442-444 [discussion 445], 2000.
24. Navarro R, Gil-Parra R, Reitman AJ, Olavarria G, Grant JA, Tomita T: Endoscopic third ventriculostomy in children: early and late complications and their avoidance. Childs Nerv Syst 22:506-513, 2006.
30. Schroeder HW, Niendorf WR, Gaab MR: Complications of endoscopic third ventriculostomy. J Neurosurg 96:1032-1040, 2002.
25. Ogiwara H, Dipatri A Jr, Alden TD, Bowman RM, Tomita T: Endoscopic third ventriculostomy for obstructive hydrocephalus in children younger than 6 months of age. Childs Nerv Syst 26:343-347, 2010. 26. Ray P, Jallo GI, Kim RY, Kim BS, Wilson S, Kothbauer K, Abbott R: Endoscopic third ventriculostomy for tumor-related hydrocephalus in a pediatric population. Neurosurg Focus 19:E8, 2005.
21. Kadrian D, van Gelder J, Florida D, Jones R, Vonau M, Teo C, Stening W, Kwok B: Long-term reliability of endoscopic third ventriculostomy. Neurosurgery 56:1271-1278 [discussion 1278], 2005.
27. Ruggiero C, Cinalli G, Spennato P, Aliberti F, Cianciulli E, Trischitta V, Maggi G: Endoscopic third ventriculostomy in the treatment of hydrocephalus in posterior fossa tumors in children. Childs Nerv Syst 20:828-833, 2004.
22. Kim SK, Wang KC, Cho BK: Surgical outcome of pediatric hydrocephalus treated by endoscopic III ventriculostomy: prognostic factors and interpreta-
28. Santamarta D, Diaz Alvarez A, Goncalves JM, Hernandez J: Outcome of endoscopic third ventriculostomy. Results from an unselected series with non-
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www.SCIENCEDIRECT.com
31. van Beijnum J, Hanlo PW, Fischer K, Majidpour MM, Kortekaas MF, Verdaasdonk RM, Vandertop WP: Laser-assisted endoscopic third ventriculostomy: long-term results in a series of 202 patients. Neurosurgery 62:437-443 [discussion 443-444], 2008.
Conflict of interest statement: The authors declare that the article content was composed in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Received 18 August 2011; accepted 02 February 2012 Citation: World Neurosurg. (2013) 79, 2S:S22.e9-S22.e12. DOI: 10.1016/j.wneu.2012.02.014 Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com 1878-8750/$ - see front matter © 2013 Elsevier Inc. All rights reserved.
WORLD NEUROSURGERY, DOI:10.1016/j.wneu.2012.02.014