SNI: Peditric Neurosurgery OPEN ACCESS For entire Editoril Bord visit : http://www.surgiclneurologyint.com Editor: Sndi Lm, MD University of Chicgo Medicl Center, Chicgo, IL, USA Cse Report Rre cse of rpidly enlrging symptomtic rchnoid cyst of the posterior foss in n infnt: A cse report nd review of the literture Nouyuki Tkeshige, Tomoko Eto, Shinji Nkshim, Kiyohiko Skt, Hiski Uchikdo, Toshi Ae 1, Motohiro Moriok Deprtments of Neurosurgery nd 1 Rdiology, Kurume University School of Medicine, Kurume, Jpn E mil: *Nouyuki Tkeshige tkeshige_nouyuki@med.kurume u.c.jp; Tomoko Eto etou_tomoko@med.kurume u.c.jp; Shinji Nkshim nkshim_shinji@med.kurume u.c.jp; Kiyohiko Skt kiyo@med.kurume u.c.jp; Hiski Uchikdo uchikdo@me.com; Toshi Ae toshie@med.kurume u.c.jp; Motohiro Moriok mmoriok@med.kurume u.c.jp *Corresponding uthor Received: 05 July 17 Accepted: 20 Jnury 18 Pulished: 07 Mrch 18 Astrct Bckground: Intrcrnil rchnoid cysts re spce occupying lesions tht typiclly remin stle or decrese in size over time. Cysts in infnts younger thn 1 yer of ge re remrkly different from those in older children nd dults in terms of cyst locliztion nd enlrgement. Archnoid cysts of the posterior foss (PFACs) re very rre in infnts nd do not typiclly grow or present with clinicl symptoms, such tht surgicl tretment is generlly considered to e unnecessry. Here, we descrie n extremely rre cse of n infnt with rpidly enlrging symptomtic PFAC tht ws successfully treted with surgery. Cse Description: A 4 month old oy presented with incresing hed circumference nd rpidly enlrging rchnoid cyst in the left posterior foss with ventriculomegly, which ws documented using seril imging over the preceding 2 months. We performed microscopic resection of the cyst memrne to remove the mss effect s soon s possile nd fcilitte norml development. To confirm durl closure nd prevent cererospinl fluid lekge, we lso performed short term (7 dys) percutneous long tunneled externl ventricle dringe fter the surgery. Mgnetic resonnce imging over 4 yer follow up period reveled dequte reduction of the ventricle nd cyst. The ptient no longer exhiited progressive mcrocrni nd showed norml development. Conclusion: To our knowledge, this is the second successful cse of surgicl tretment of n enlrging symptomtic PFAC in n infnt. Our surgicl strtegy for the tretment of this rre cse cn serve s guide for surgeons in similr future cses. Access this rticle online Wesite: www.surgiclneurologyint.com DOI: 10.4103/sni.sni_245_17 Quick Response Code: Key Words: Archnoid cyst, cyst enlrgement, hydrocephlus, posterior foss This is n open ccess rticle distriuted under the terms of the Cretive Commons Attriution NonCommercil ShreAlike 3.0 License, which llows others to remix, twek, nd uild upon the work non commercilly, s long s the uthor is credited nd the new cretions re licensed under the identicl terms. For reprints contct: reprints@medknow.com How to cite this rticle: Tkeshige N, Eto T, Nkshim S, Skt K, Uchikdo H, Ae T, et l. Rre cse of rpidly enlrging symptomtic rchnoid cyst of the posterior foss in n infnt: A cse report nd review of the literture. Surg Neurol Int 2018;9:57. http://surgiclneurologyint.com/rre-cse-of--rpidly-enlrging-symptomtic-rchnoid-cyst-of-the-posterior-foss-in-n-infnt:-a-cse-report-nd-review-of-the-literture/ 2018 Surgicl Neurology Interntionl Pulished y Wolters Kluwer - Medknow
INTRODUCTION Congenitl rchnoid cysts re rre centrl nervous system mlformtions tht represent only 1 2% of ll intrcrnil msses. [23] These lesions re often cliniclly silent nd rrely increse in size. [1,12,13,19] As such, rchnoid cysts seldom require surgicl intervention. The chrcteristics of rchnoid cysts vry remrkly etween infnts nd older children or dults. In dults, the mjority of intrcrnil rchnoid cysts rise in the suprtentoril region (90%), with the middle crnil foss eing the most common site (60%) of origin nd 10 20% of rchnoid cysts occurring in the posterior foss. [4,7,22] In contrst, rchnoid cysts in infnt ptients commonly occur t the middle foss (15%) nd intrventiculrly (14%), with very low percentges occurring in the posterior fosse (4.6%). [13] Lee et l. recently reported tht cysts in infnts cn occsionlly enlrge (16.2%), ut tht rchnoid cysts of the posterior foss (PFACs) hve n extremely low prevlence of enlrgement in infnt cses (2.3%) [13] nd re generlly symptomtic such tht they do not require tretment. Here, we present n extremely rre cse of 4 month old oy who presented with rpidly enlrging symptomtic PFAC. After considering the current options for treting symptomtic PFACs in infnts, [1,3,11,14,18,22,24] we performed necessry microscopic memrnectomy with post surgicl percutneous long tunneled externl ventricle dringe (PL EVD) [5,15] nd otined good outcome. Becuse this is the second successful cse of surgicl tretment for n enlrging symptomtic PFAC in n infnt, [3] the surgicl strtegy descried here cn guide surgeons in future clinicl decisions. CASE PRESENTATION History The ptient in the present cse ws oy tht ws orn y vginl delivery t 42 weeks of gesttion. He hd irth weight of 2546 g, norml hed circumference (32.1 cm), nd exhiited no neurologicl normlities. Bsed on the detection of n ultrsonogrphic normlity, mgnetic resonnce imging (MRI) ws performed t 58 dys fter irth nd cystic lesion (1.2 cm 2.9 cm t its lrgest dimeter) ws identified in the left retrocereellr region of the posterior foss [Figure 1]. The cereellum ws smller thn verge, ut there were no signs of significnt compression. At this time, the circumference of the ptient s hed ws slightly enlrged nd mesured in the upper limit for his ge group (43.0 cm). Exmintions At 4 months of ge, the ptient s hed circumference incresed to 48.0 cm (>2 stndrd devitions ove the men for his ge), nd MRI showed significnt Figure 1: Initil sgittl () nd xil () T2 mgnetic resonnce imges of the mle ptient t 58 dys of ge. The imge demonstrtes cystic lesion with the septum (rrow) in the posterior foss enlrgement of the cyst (4.0 cm 3.5 cm t its lrgest dimeter) with compression of the cereellum nd hydrocephlus cused y ostruction of the fourth ventricle outlets [Figure 2]. Intrcrnil hypertension ws lso recognized sed on sunset phenomen in the ptient s eyes, sclp vricosis, nd seprtion of the coronl nd sgittl crnil sutures. The ptient did not exhiit ny other norml neurologicl signs, nd ws dignosed with n enlrging PFAC nd ostructive hydrocephlus. Surgicl procedure Clinicl signs nd symptoms of hydrocephlus were oserved when the ptient ws 4 months of ge. Thus, we performed suoccipitl crniotomy nd direct microscopic tretments to resect the cyst memrne vi medil occipitl pproch with the ptient in the prone position. This ws done to restore norml communiction etween the Mgendie nd Lushk formin nd the surchnoid spce. Becuse the inner memrne of the cyst dhered to the rostrl medullry velum nd compressed the fourth ventricle, we crefully detched nd resected oth the outer nd inner memrnes of the cyst to open the fourth ventricle nd cistern mgn [Figure 3]. During the surgery, we confirmed good cererospinl fluid (CSF) flow t the cererl queduct nd cistern mgn. A histopthologicl study of excised tissues stined with hemtoxylin nd eosin showed rchnoid mesothelil cells rrnged mong fiers of the connective tissue (dt not shown), confirming our dignosis. Immeditely prior to the crniotomy, we performed PL EVD to llow for externl CSF dringe for 7 dys fter the surgery to prevent infection due to CSF lekge. [5] The procedure of PL EVD ws s follows. The posterior horn of the lterl ventricle ws cnnulted with ventriculr ctheter. The peritonel ctheter ws then sucutneously tunneled with the proximl end connected to the distl end exiting t the lower nterior
Figure 2: Preopertive sgittl () nd xil () T2 mgnetic resonnce imges of the ptient t 4 months of ge. An enlrged cystic lesion cn e oserved descending into the formen mgnum with the septum expnding eyond the midline (rrow). Blocked communiction with the fourth ventricle, compression of the rinstem nd fourth ventricle (rrowheds), nd mrked ventriculomegly (strs) were evident chest wll, 25 cm wy from the proximl end. The distl ctheter ws then secured to the skin nd connected to ventriculr dringe system. Postopertive course The postopertive course ws uneventful. MRI performed 1 month fter the surgery reveled tht the cyst hd disppered, lleviting compression of the cereellum nd hlting the ptient s mcrocrni. Further, the sulci of the cereellum nd the cereellr pontine ngle ecme esier to oserve. At the lst follow up (performed 4 yers postopertively), the cyst wll ws unidentifile nd the cereellum hd grown to ner norml size [Figure 4]. The ptient ws doing well nd showed norml development. DISCUSSION An rchnoid cyst consists of cvity lined with rchnoid cells nd filled with fluid tht closely resemles CSF. [23] Most rchnoid cysts re cliniclly silent nd remin sttic in size; however, on rre occsions, these cysts cn increse in size nd produce symptoms due to mss effects. [1,12,13,19] Although the mechnisms tht drive rchnoid cyst enlrgement remin unknown, it hs een postulted tht cysts my expnd due to (1) ll vlve ction tht llows CSF entry into the cyst; (2) intrcystic production of fluid y secreting cells occsionlly found on the cyst wlls; or (3) movement of fluids following n osmotic grdient. [10,23] The differentil dignosis of PFACs in infnts minly includes the Dndy Wlker mlformtion, meg cistern mgn, nd Blke s pouch cyst. [6,23] It is lso importnt to exclude other possile cystic lesions such s cereellr cystic strocytom, cystic hemngliolstom, nd epidermoid or dermoid tumors. [6] MRI findings re c Figure 3: Intropertive photogrphs. ( nd ) The cyst wll ws exposed nd resected. (c) Opening of the cererl queduct ws confirmed. (d) Opening of the formen mgnum ws confirmed very useful for the differentil dignosis of PFAC, s demonstrted in our present cse. Finlly, postopertive histologicl studies re lso useful for definitive dignosis. Although very little dt exist regrding the clinicl chrcteristics of rchnoid cysts in infnt cses, these chrcteristics hve grdully ecome evident. [3,11,13,18,20] Lee et l. demonstrted differences in cyst locliztion etween infnts younger thn 1 yer of ge nd older children nd dults, dditionlly indicting much lower prevlence of PFACs in infnts compred to dults. [13] Further, the uthors found tht even enlrging PFACs in infnts did not necessrily wrrnt surgicl tretment sed on the sence of clinicl symptoms. Accordingly, the present cse of 4 month old oy with rpidly enlrging symptomtic PFAC nd successful surgicl tretment is extremely rre nd thus of clinicl vlue. To dte, only 2 cses of enlrging symptomtic PFACs nd surgicl tretment hve een reported in infnt ptients [Tle 1]. [3] Both ptients in these cses were younger thn 9 months of ge nd were treted y endoscopic fenestrtion, ut clinicl improvement ws reported in only 1 cse. Thus, our present cse is the second report of successful surgicl tretment of rpidly enlrging symptomtic PFAC in n infnt. [3] The infrtentoril spce is much smller thn the suprtentoril spce; ccordingly, mss effects relted to rchnoid cysts re more prole in the infrtentoril spce thn in the suprtentoril spce. Especilly in infnts with very smll infrtentoril spces, mss effects must e removed s soon s possile to fcilitte norml development. PFACs cn e prticulrly chllenging to tret depending on the cyst size, cyst loction, nd the presence of ostructive hydrocephlus. [6,21] To this d
Tle 1: Reported infnt cses of enlrging symptomtic rchnoid cysts of the posterior foss with surgicl tretment Authors Age/sex Age t dignosis Symptoms nd neurologicl findings Surgicl tretment Outcome Choi [3] 3 m uk Uk Uk Endoscopic fenestrtion No clinicl improvement, sudurl fluid collection Choi [3] 9 m/uk Uk Hydrocephlus Endoscopic fenestrtion Clinicl improvement Present report 4 m/m 58 dys Hydrocephlus, intrcrnil hypertension Open cyst excision + PL EVD Clinicl improvement M: Mle, m: Month, PL EVD: Percutneous long tunneled externl ventricle dringe, uk: Unknown Figure 4: Computed tomogrphy performed 4 yers fter the surgery. The imge demonstrtes sence of the septum s well s reduced compression of the rinstem nd fourth ventricle. Furthermore, the imge clerly depicts the sulci of the cereellum, the cereellopontine ngle, nd meliortion of the ptient s ostructive hydrocephlus end, there is no consensus regrding stndrd or optiml surgicl tretment for PFAC. Vrious tretment pproches exist, including microsurgicl excision or fenestrtion y crniotomy, cyst shunting, nd endoscopic fenestrtion. [1,3,11,14,18,22,24] While some uthors hve reported tht there is no significnt difference etween these surgicl methods, [2,8] studies evluting the mngement of PFACs in peditric popultion demonstrted tht crniotomy with excision ws the first line pproch. [14,16] We selected to perform microscopic memrnectomy of oth the inner nd outer memrnes ecuse the resolution of ostructive hydrocephlus ws high priority nd it ws necessry to remove the mss effect to fcilitte norml development of the infnt. There is reltively high risk of postopertive complictions such s CSF lekge, sudurl fluid collection, nd meningitis fter surgery on the posterior foss, especilly in infnts. [3,9,17,18] In the present cse, we performed PL EVD nd continued dringe for 7 dys fter surgery to confirm durl closure nd prevent CSF lekge, which my hve led to n infection such s meningitis. [5,15] After removl of the dringe tue, no CSF lekge or meningitis ws oserved nd the skin wound heled completely. The resons for performing PL EVD re s follows: (1) it is very difficult to stitch nd effectively close n incision of the dur mter in the posterior foss region in infnts; (2) s the skin, sucutneous ft, nd muscles of infnts re reltively thin, CSF tends to lek externlly when the dur mter is reched; (3) it is difficult to evlute whether infnt ptients hve sufficient ility to resor leked CSF; nd (4) PL EVD is simple nd effective method for lowering the risk of infection fter surgicl tretment of PFAC. [15] To our knowledge, this is the first cse in which PL EVD performed in n infnt with PFAC. Another necessry precution during surgicl intervention for PFAC is the protection of importnt neurovsculr structures such s the rinstem. In summry, these surgicl considertions nd techniques provide importnt nd useful insight for neurosurgeons plnning surgicl tretment for PFACs in infnt ptients. Declrtion of ptient consent The uthors certify tht they hve otined ll pproprite ptient consent forms. In the form the ptient(s) hs/hve given his/her/their consent for his/her/ their imges nd other clinicl informtion to e reported in the journl. The ptients understnd tht their nmes nd initils will not e pulished nd due efforts will e mde to concel their identity, ut nonymity cnnot e gurnteed. Finncil support nd sponsorship Nil. Conflicts of interest There re no conflicts of interest. REFERENCES 1. Al Holou WN, Yew AY, Boomsd ZE, Grton HJL, Murszko KM, Mher CO. Prevlence nd nturl history of rchnoid cysts in children. J Neurosurg Peditr 2010;5:578 85. 2. Ali ZS, Lng SS, Bkr D, Storm PB, Stein SC. Peditric intrcrnil rchnoid cysts: Comprtive effectiveness of surgicl tretment options. Childs Nerv Syst 2014;30:461 9. 3. Choi JW, Lee JY, Phi JH, Kim S K, Wng KC. Stricter indictions re recommended for fenestrtion surgery in intrcrnil rchnoid cysts of children. Childs Nerv Syst 2015;31:77 86. 4. Cincu R, Agrwl A, Eirs J. Intrcrnil rchnoid cysts: Current concepts nd tretment lterntives. Clin Neurol Neurosurg 2007;109:837 43. 5. Collins CD, Hrtley JC, Chkrorty A, Thompson DN. Long sucutneous tunnelling reduces infection rtes in peditric externl ventriculr drins. Childs Nerv Syst 2014;30:1671 8. 6. Edingler P, Kynr MY, Bozkus H, Qiplk N. Posterior foss rchnoid cysts. Br J Neurosurg 1999;13:10 7. 7. Fulkerson DH, Vogel TD, Bker A, Ptel N, Ackermn L, Smith JL, et l.
Cyst ventricle stent s primry or slvge tretment for posterior foss rchnoid cysts. J Neurosurg Peditr 2011;7:549 56. 8. Gngemi M, Senec V, Colell G, Cioffi V, Imperto A, Miuri F. Endoscopy versus microsurgicl cyst excision nd shunting for treting intrcrnil rchnoid cysts. J Neurosurg Peditr 2011;8:158 64. 9. Gnnlinghm KK, Hfuente J, Thompson D, Hrkness W, Hywrd R. Surgicl procedures for posterior foss tumors in children: Does crniotomy led to fewer complictions thn crnioectomy. J Neurosurg 2002;97:821 6. 10. Hlni H, Min MS, Sfin G, Heilmn CB. Archnoid cyst slit vlves: the mechnism for rchnoid cyst enlrgement. Report of 5 cses. J Neurosurg Peditr 2013;12:62 6. 11. King JAJ, Auguste KI, Hllidy W, Drke JM, Kulkrni AV. Ventriculocystostomy nd endoscopic third ventriculostomy/shunt plcement in the mngement of hydrocephlus secondry to gint retrocereellr cysts in infncy. J Neurosurg Peditr 2010;5:403 7. 12. Kumgi M, Ski N, Ymd H, Shinod J, Nkshim T, Iwm T, et l. Postntl development nd enlrgement of primry middle crnil foss rchnoid cyst recognized on repet CT scn. Childs Nerv Syst 1986;2:211 5. 13. Lee JY, Kim JW, Phi JH, Kim SK, Cho BK, Wng KC. Enlrging rchnoid cyst: A flse lrm for infnts. Childs Nerv Syst 2012;28:120311. 14. Mrin Snri EA, Ymmoto H, Ngshim T, Kohmur E. Evlution of the mngement of rchnoid cyst of the posterior foss in peditric popultion: Experience over 27 yers. Childs Nerv Syst 2007;23:535 42. 15. Mtsumoto J, Kochi M, Moriok M, Nkmur H, Mkino K, Hmd J, et l. A long term ventriculr dringe for ptients with germ cell tumors or medullolstom. Surg Neurol 2006;65:74 80. 16. Oeruer RW, Hse J, Pucher R. Archnoid cysts in children: A Europen co opertive study. Childs Nerv Syst 1992;8:281 6. 17. Prizek J, Merick P, Nemecek S, Nemeckov J, Spcek J, Su P, et l. Posterior crnil foss surgery in 454 children. Comprison of results otined in pre CT nd CT er nd fter vrious types of mngement of dur mter. Childs Nerv Syst 1998;14:426 38. 18. Rju S, Shrm RS, Moningi S, Momin J. Neuroendoscopy for Intrcrnil Archnoid Cysts in Infnts: Therpeutic Considertions. J Neurol Surg 2015;77:333 43. 19. Ro G, Anderson RCE, Feldstein NA, Brockmeyer DL. Expnsion of rchnoid cysts in children. J Neurosurg 2015;102:314 7. 20. Sikorski CW, Ymni B, Frim DM. Endoscopic cyst fenestrtion outcomes in children one yer of ge or less. Peditr Neurosurg 2004;40:59 63. 21. Srinivsn US, Lwrence R. Posterior foss rchnoid cysts in dults: Surgicl strtegy: Cse series. Asin J Neurosurg 2015;10:47 51. 22. Tsuoi Y, Hmd H, Hyshi N, Kurimoto M, Hirshim Y, Endo S. Huge rchnoid cyst in the posterior foss: Controversil discussion for selection of the surgicl pproch, Childs Nerv Syst 2005;21:259 61. 23. Wilkinson CC, Wilson KR. Congenitl rchnoid cyst nd Dndy Wlker complex. In: Alright AL, Pollck IF, Adelson PD editors. Principles nd Prctice of Peditric Neurosurgery. 2 nd edition. Thieme: New York; 2008; pp 162 86. 24. Zd G, Krieger MD, McNtt S, Bowen I, McCom JG. Pthogenesis nd tretment of intrcrnil rchnoid cysts in peditric ptients younger thn 2 yers of ge. Neurosurg Focus 2007;22:E1.