- Email: [email protected]
Intraoperative Visualization of a Spinal Arachnoid Cyst Using Pyoktanin Blue
Technical Note
Intraoperative Visualization of a Spinal Arachnoid Cyst Using Pyoktanin Blue Soichiro Takamiya1, Toshitaka Seki1, Kazuyoshi Yamazaki1, Toru Sasamori2, Kiyohiro Houkin1
BACKGROUND: Spinal arachnoid cysts (SACs) are filled with cerebrospinal fluid, and they include the arachnoid membrane, making it difficult to distinguish the walls of the cyst from the arachnoid membrane and excise the cyst as a lump. Here we report a technique for the intraoperative visualization of SACs, involving the use of pyoktanin blue.
-
METHODS: Four patients with spinal intradural arachnoid cysts underwent total excision of the cysts between October 2016 and April 2017. In 1 case, magnetic resonance imaging revealed the cyst clearly, but in the other cases, the cysts were unclear. All cysts were injected with 1% pyoktanin blue (Wako Pure Chemical Industries, Osaka, Japan) diluted 500 times with physiological saline before excision. When it was difficult to distinguish the cyst from the normal arachnoid membrane, 1% pyoktanin blue diluted 1000 times with physiological saline was injected into both the cyst and the subarachnoid space, and the spread of the stain was observed.
-
RESULTS: The cysts were better visualized after pyoktanin blue injection than before injection. When it was difficult to distinguish the cyst from the normal arachnoid space, pyoktanin blue injection was useful for judging the cyst space. There were no perioperative complications, and the patients’ symptoms improved partially or completely after treatment.
-
CONCLUSIONS: Our technique of pyoktanin blue injection into SACs could make their excision easy and safe.
-
INTRODUCTION
A
spinal arachnoid cyst (SAC) is a sac filled with cerebrospinal fluid, involving the arachnoid membrane.1 SAC is a relatively rare condition, and its management remains controversial.1,2
Key words Excision - Injection - Pyoktanin blue - Spinal arachnoid cyst -
Abbreviations and Acronyms MRI: Magnetic resonance imaging SAC: Spinal arachnoid cyst
Differentiating the walls of SACs and the arachnoid membrane is difficult, and thus it sometimes cannot be excised as a lump and must be excised in pieces. The incomplete excision of these cysts can lead to recurrence, and the forceful excision of small fragments might lead to complications. Here we present a technique for the intraoperative visualization of SACs, involving the use of pyoktanin blue. We believe that this technique allows the safe excision of SACs.
METHODS Patients Four patients with SACs underwent total cyst excision at Hokkaido University Hospital between October 2016 and April 2017. All patients had some symptoms, which were suspected to be caused by the cysts. The patient details are presented in Table 1. Magnetic resonance imaging (MRI) revealed the cyst clearly in case 1 (Figure 1); conversely, the borders of the cysts were obscure in cases 2 (Figure 2), 3 (Figure 3), and 4 (Figure 4). All patients underwent excision of the cysts according to the procedure presented below. Surgical Procedure All SACs were approached via laminectomy. If the border of the cyst was unclear on preoperative MRI, we kept the laminectomy small to avoid wasted effort. After a dural incision, cysts were injected with 1% pyoktanin blue (Wako Pure Chemical Industries, Osaka) diluted 500 times with physiological saline, and then total excision was performed with guidance from the staining. When it was difficult to distinguish the cyst from the normal arachnoid membrane, we injected 1% pyoktanin blue diluted 1000 times with physiological saline into both the cyst and the subarachnoid space, and observed the spread of the stain. After cyst excision, the dural incision was sutured with a Gore-Tex suture (W.L. Gore & Associates, Tokyo, Japan). To prevent cerebrospinal fluid leakage, fat tissue and a Neoveil
From the 1Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo; and 2Department of Neurosurgery, Sapporo Azabu Neurosurgical Hospital, Sapporo, Japan To whom correspondence should be addressed: Soichiro Takamiya, M.D. [E-mail: [email protected]] Citation: World Neurosurg. (2018) 109:18-23. https://doi.org/10.1016/j.wneu.2017.09.031 Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2017 Elsevier Inc. All rights reserved.
18
www.SCIENCEDIRECT.com
WORLD NEUROSURGERY, https://doi.org/10.1016/j.wneu.2017.09.031
TECHNICAL NOTE
Table 1. Characteristics of Spinal Intradural Arachnoid Cysts Patient
Age (Years), Sex
Cyst Location
Gait Disturbance
Leg Numbness
Side Chest Pain
MRI Finding
1
68, male
Th2/3
þ
þ
Clear
2
72, female
Th5/6
þ
Unclear
3
44, male
Th2/3
þ
Unclear
4
44, female
Th4/5
þ
þ
Unclear
MRI, magnetic resonance imaging.
sheet (Gunze, Osaka, Japan) with fibrin glue were placed on the suture line. Then the wound was closed in layers. RESULTS The mean operative duration was 239 minutes (range, 207e256 minutes), and the mean duration of cyst excision was 13.8 minutes (range, 5e22 minutes). There were no perioperative complications. Compared with the cyst before staining (Figure 5A), pyoktanin blue allowed for clear visualization of the
Figure 1. Sagittal magnetic resonance imaging of the cyst in case 1. A T2-weighed image (left) shows that the dorsal side of the spinal cord is dented at level
WORLD NEUROSURGERY 109: 18-23, JANUARY 2018
cyst wall and made excision of the stained cyst easy and safe (Figure 5B). In case 4, it was difficult to distinguish the cyst from the normal arachnoid space (Figure 6A). In this case, we injected 1% pyoktanin blue diluted 1000 times with physiological saline into both the cyst and the subarachnoid space (Figure 6B and D). The stain was stagnant at 1 minute after injection in 1 of the spaces (Figure 6C), and it washed out 1 minute after injection in the other space (Figure 6E). We considered the former space a part of the
Th2/3 (arrow), and a heavy T2-weighted image (right) shows the cyst clearly at the same level (arrow).
www.WORLDNEUROSURGERY.org
19
TECHNICAL NOTE
Figure 2. Sagittal magnetic resonance imaging in case 2. A T2-weighed image (left) and heavy T2weighted image (right) show that the dorsal side of the
arachnoid cyst, and extended the laminectomy and dural incision to the caudal side under guidance of the cyst stain (Figure 6F). After surgery, all patients exhibited partial or complete improvement of symptoms.
DISCUSSION SACs are sacs involving the arachnoid membrane and are classified into the following 3 categories: type I (extradural arachnoid cysts without spinal nerve root fibers), type II (extradural arachnoid cysts with spinal nerve root fibers), and type III (intradural arachnoid cysts).3 Generally, a surgical procedure is not selected if the patient does not have any neurologic symptoms. On the other hand, management for symptomatic patients remains
20
www.SCIENCEDIRECT.com
spinal cord is dented at level Th5/6 (arrow), but it is unclear whether there is a cyst.
controversial.1,2 In type I and II cysts, some authors insist that fenestration of the cyst wall is sufficient,4 whereas others believe it necessary to excise the cyst completely to prevent recurrence.5 Meanwhile, for type III cysts, there has not been a sufficient discussion on the most appropriate procedure. We believe that total excision is better for type lII cysts to prevent recurrence, and we try to remove cysts completely if the procedure can be carried out safely. Pyoktanin blue is usually used in gram staining for bacteriological examination, but some authors have reported its usefulness in the neurologic field. Kamiyama et al.6 described its efficacy in anastomotic bypass surgery; Tomita et al.7 and Hayashi et al.8 reported its use during removal of cystic brain tumors, and Nishido et al.9 described a method involving pyoktanin blue for staining
WORLD NEUROSURGERY, https://doi.org/10.1016/j.wneu.2017.09.031
TECHNICAL NOTE
Figure 3. Sagittal magnetic resonance imaging in case 3. A T2-weighed image (left) and heavy T2-weighted image (right) show that the dorsal
side of the spinal cord is dented at level Th2/3 (arrow), but it is unclear whether there is a cyst.
Figure 4. Sagittal magnetic resonance images of the cyst in case 4. A T2-weighed image (left) and heavy T2-weighted image (right) show that the
spinal cord is compressed from the dorsal side at level Th5/6, but it is unclear whether there is a cyst.
WORLD NEUROSURGERY 109: 18-23, JANUARY 2018
www.WORLDNEUROSURGERY.org
21
TECHNICAL NOTE
fractured plaques in carotid artery stenting. Stating in October 2016, we have used pyoktanin blue to enhance the visibility of arachnoid cysts. This use is based on the following properties:
Figure 5. Intraoperative findings in case 1. The cyst wall is unclear before injecting pyoktanin blue (upper). It became clear after staining with pyoktanin blue (lower).
Figure 6. Intraoperative findings in case 4. It is difficult to distinguish the cyst from the normal arachnoid space (A). Pyoktanin blue is injected into both spaces (B and D). Pyoktanin blue is stagnant 1 minute after injection in one of the
22
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Safe excision. When pyoktanin blue is not used, the cyst border remains unclear, and the cyst often must be divided into several pieces, increasing the risk of retention of cyst residue and other complications. As mentioned above, the SAC can be easily excised as a lump after staining with pyoktanin blue. Distinguishing the cyst from the arachnoid membrane. Sometimes the entire cyst cannot be visualized because of an inadequate laminectomy or dural incision, even if the cyst border is noted. In such a situation, pyoktanin blue injection into the cyst and the subarachnoid space can be useful. If pyoktanin blue is injected into the cyst, the stain will stagnate; however, if it is injected into the subarachnoid space, it will be washed out. We used a more diluted pyoktanin blue solution to easily make observations. Avoiding unnecessary laminectomy or dural incision. Laminectomy or dural incision should be extended when it is not sufficient. Without any landmarks, superfluous procedures may be performed. Pyoktanin blue injection into the cyst can help avoid unnecessary laminectomy or dural incision. Yamaguchi et al.10 reported a technique for evaluating regional cerebrospinal fluid flow in focal arachnoid pathologies, such as an arachnoid web or adhesive arachnoiditis. In their study, they injected
spaces (C). It is washed out 1 minute after injection in the other space (E). The laminectomy and dural incision are extended with guidance from the staining of the cyst (F).
WORLD NEUROSURGERY, https://doi.org/10.1016/j.wneu.2017.09.031
TECHNICAL NOTE
gentian violet into the subarachnoid space to observe whether the intensity of the dye diminished, based on which they determined the range of arachnoid lysis. Their procedure was similar to ours but had a different focus. We emphasize that the goal of our procedure was not only to observe cerebrospinal fluid flow, but also to use the dye as a guide. We use pyoktanin blue at a concentration of 0.001%e0.002%, lower than that mentioned in previous reports.6-9 There have been no reports of complications or toxicities associated with the use of pyoktanin blue in the neurologic field, and there are no
REFERENCES 1. French H, Somasundaram A, Biggs M, Parkinson J, Allan R, Ball J, et al. Ideopathic intradural dorsal thoracic arachnoid cysts: a case series and review of the literature. J Clin Neurosci. 2017;40:147-152. 2. Woo JB, Son DW, Kang KT, Lee JS, Song GS, Sung SK, et al. Spinal extradural arachnoid cyst. Korean J Neurotrauma. 2016;12:185-190. 3. Nabors MW, Pait TG, Byrd EB, Karim NO, Davis DO, Kobrine AI, et al. Updated assessment and current classification of spinal meningeal cysts. J Neurosurg. 1988;68:366-377. 4. Choi SW, Seong HY, Roh SW. Spinal extradural arachnoid cyst. J Korean Neurosurg Soc. 2013;54: 355-358. 5. Lee CH, Hyun SJ, Kim KJ, Jahng TA, Kim HJ. What is a reasonable surgical procedure for spinal extradural arachnoid cysts: is cyst removal
contraindications according to the drug information; therefore, we believe that our technique is not harmful for patients. Our procedure has some limitations. Although our method makes it easy and safe to excise SACs, we used pyoktanin blue of a certain concentration. There may be a much better pyoktanin concentration for observing SACs.
CONCLUSION Our technique of using pyoktanin blue for visualizing SACs during surgery can help improve the ease and safety of cyst excision.
mandatory? Eight consecutive cases and a review of the literature. Acta Neurochir (Wien). 2012;154: 1219-1227. 6. Kamiyama H, Takahashi A, Houkin K, Mabuchi S, Abe H. Visualization of the ostium of an arteriotomy in bypass surgery. Neurosurgery. 1993;33: 1109-1110. 7. Hayashi N, Sasaki T, Tomura N, Okada H, Kuwata T. Removal of a malignant cystic brain tumor utilizing pyoktanin blue and fibrin glue: technical note. Surg Neurol Int. 2017;8:24.
10. Yamaguchi S, Hida K, Takeda M, Mitsuhara T, Morishige M, Yamada N, et al. Visualization of regional cerebrospinal fluid flow with a dye injection technique in focal arachnoid pathologies. J Neurosurg Spine. 2015;22:554-557.
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 31 July 2017; accepted 6 September 2017 8. Tomita Y, Sasaki T, Tanabe T, Idei M, Muraoka K, Terada K, et al. Pyoktanin blue injection for resection of cystic brain tumor: a case report. No Shinkei Geka. 2013;41:687-691 [in Japanese].
Citation: World Neurosurg. (2018) 109:18-23. https://doi.org/10.1016/j.wneu.2017.09.031 Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com
9. Nishido H, Hoya K, Kugasawa K, Iwakami T, Miyamoto S, Murakami M. Pyoktanin blue method for staining fractured plaques. J Neuroendovasc Ther. 2016;10:84-87.
WORLD NEUROSURGERY 109: 18-23, JANUARY 2018
1878-8750/$ - see front matter ª 2017 Elsevier Inc. All rights reserved.
www.WORLDNEUROSURGERY.org
23
Intraoperative Visualization of a Spinal Arachnoid Cyst Using Pyoktanin Blue Soichiro Takamiya1, Toshitaka Seki1, Kazuyoshi Yamazaki1, Toru Sasamori2, Kiyohiro Houkin1
BACKGROUND: Spinal arachnoid cysts (SACs) are filled with cerebrospinal fluid, and they include the arachnoid membrane, making it difficult to distinguish the walls of the cyst from the arachnoid membrane and excise the cyst as a lump. Here we report a technique for the intraoperative visualization of SACs, involving the use of pyoktanin blue.
-
METHODS: Four patients with spinal intradural arachnoid cysts underwent total excision of the cysts between October 2016 and April 2017. In 1 case, magnetic resonance imaging revealed the cyst clearly, but in the other cases, the cysts were unclear. All cysts were injected with 1% pyoktanin blue (Wako Pure Chemical Industries, Osaka, Japan) diluted 500 times with physiological saline before excision. When it was difficult to distinguish the cyst from the normal arachnoid membrane, 1% pyoktanin blue diluted 1000 times with physiological saline was injected into both the cyst and the subarachnoid space, and the spread of the stain was observed.
-
RESULTS: The cysts were better visualized after pyoktanin blue injection than before injection. When it was difficult to distinguish the cyst from the normal arachnoid space, pyoktanin blue injection was useful for judging the cyst space. There were no perioperative complications, and the patients’ symptoms improved partially or completely after treatment.
-
CONCLUSIONS: Our technique of pyoktanin blue injection into SACs could make their excision easy and safe.
-
INTRODUCTION
A
spinal arachnoid cyst (SAC) is a sac filled with cerebrospinal fluid, involving the arachnoid membrane.1 SAC is a relatively rare condition, and its management remains controversial.1,2
Key words Excision - Injection - Pyoktanin blue - Spinal arachnoid cyst -
Abbreviations and Acronyms MRI: Magnetic resonance imaging SAC: Spinal arachnoid cyst
Differentiating the walls of SACs and the arachnoid membrane is difficult, and thus it sometimes cannot be excised as a lump and must be excised in pieces. The incomplete excision of these cysts can lead to recurrence, and the forceful excision of small fragments might lead to complications. Here we present a technique for the intraoperative visualization of SACs, involving the use of pyoktanin blue. We believe that this technique allows the safe excision of SACs.
METHODS Patients Four patients with SACs underwent total cyst excision at Hokkaido University Hospital between October 2016 and April 2017. All patients had some symptoms, which were suspected to be caused by the cysts. The patient details are presented in Table 1. Magnetic resonance imaging (MRI) revealed the cyst clearly in case 1 (Figure 1); conversely, the borders of the cysts were obscure in cases 2 (Figure 2), 3 (Figure 3), and 4 (Figure 4). All patients underwent excision of the cysts according to the procedure presented below. Surgical Procedure All SACs were approached via laminectomy. If the border of the cyst was unclear on preoperative MRI, we kept the laminectomy small to avoid wasted effort. After a dural incision, cysts were injected with 1% pyoktanin blue (Wako Pure Chemical Industries, Osaka) diluted 500 times with physiological saline, and then total excision was performed with guidance from the staining. When it was difficult to distinguish the cyst from the normal arachnoid membrane, we injected 1% pyoktanin blue diluted 1000 times with physiological saline into both the cyst and the subarachnoid space, and observed the spread of the stain. After cyst excision, the dural incision was sutured with a Gore-Tex suture (W.L. Gore & Associates, Tokyo, Japan). To prevent cerebrospinal fluid leakage, fat tissue and a Neoveil
From the 1Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo; and 2Department of Neurosurgery, Sapporo Azabu Neurosurgical Hospital, Sapporo, Japan To whom correspondence should be addressed: Soichiro Takamiya, M.D. [E-mail: [email protected]] Citation: World Neurosurg. (2018) 109:18-23. https://doi.org/10.1016/j.wneu.2017.09.031 Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2017 Elsevier Inc. All rights reserved.
18
www.SCIENCEDIRECT.com
WORLD NEUROSURGERY, https://doi.org/10.1016/j.wneu.2017.09.031
TECHNICAL NOTE
Table 1. Characteristics of Spinal Intradural Arachnoid Cysts Patient
Age (Years), Sex
Cyst Location
Gait Disturbance
Leg Numbness
Side Chest Pain
MRI Finding
1
68, male
Th2/3
þ
þ
Clear
2
72, female
Th5/6
þ
Unclear
3
44, male
Th2/3
þ
Unclear
4
44, female
Th4/5
þ
þ
Unclear
MRI, magnetic resonance imaging.
sheet (Gunze, Osaka, Japan) with fibrin glue were placed on the suture line. Then the wound was closed in layers. RESULTS The mean operative duration was 239 minutes (range, 207e256 minutes), and the mean duration of cyst excision was 13.8 minutes (range, 5e22 minutes). There were no perioperative complications. Compared with the cyst before staining (Figure 5A), pyoktanin blue allowed for clear visualization of the
Figure 1. Sagittal magnetic resonance imaging of the cyst in case 1. A T2-weighed image (left) shows that the dorsal side of the spinal cord is dented at level
WORLD NEUROSURGERY 109: 18-23, JANUARY 2018
cyst wall and made excision of the stained cyst easy and safe (Figure 5B). In case 4, it was difficult to distinguish the cyst from the normal arachnoid space (Figure 6A). In this case, we injected 1% pyoktanin blue diluted 1000 times with physiological saline into both the cyst and the subarachnoid space (Figure 6B and D). The stain was stagnant at 1 minute after injection in 1 of the spaces (Figure 6C), and it washed out 1 minute after injection in the other space (Figure 6E). We considered the former space a part of the
Th2/3 (arrow), and a heavy T2-weighted image (right) shows the cyst clearly at the same level (arrow).
www.WORLDNEUROSURGERY.org
19
TECHNICAL NOTE
Figure 2. Sagittal magnetic resonance imaging in case 2. A T2-weighed image (left) and heavy T2weighted image (right) show that the dorsal side of the
arachnoid cyst, and extended the laminectomy and dural incision to the caudal side under guidance of the cyst stain (Figure 6F). After surgery, all patients exhibited partial or complete improvement of symptoms.
DISCUSSION SACs are sacs involving the arachnoid membrane and are classified into the following 3 categories: type I (extradural arachnoid cysts without spinal nerve root fibers), type II (extradural arachnoid cysts with spinal nerve root fibers), and type III (intradural arachnoid cysts).3 Generally, a surgical procedure is not selected if the patient does not have any neurologic symptoms. On the other hand, management for symptomatic patients remains
20
www.SCIENCEDIRECT.com
spinal cord is dented at level Th5/6 (arrow), but it is unclear whether there is a cyst.
controversial.1,2 In type I and II cysts, some authors insist that fenestration of the cyst wall is sufficient,4 whereas others believe it necessary to excise the cyst completely to prevent recurrence.5 Meanwhile, for type III cysts, there has not been a sufficient discussion on the most appropriate procedure. We believe that total excision is better for type lII cysts to prevent recurrence, and we try to remove cysts completely if the procedure can be carried out safely. Pyoktanin blue is usually used in gram staining for bacteriological examination, but some authors have reported its usefulness in the neurologic field. Kamiyama et al.6 described its efficacy in anastomotic bypass surgery; Tomita et al.7 and Hayashi et al.8 reported its use during removal of cystic brain tumors, and Nishido et al.9 described a method involving pyoktanin blue for staining
WORLD NEUROSURGERY, https://doi.org/10.1016/j.wneu.2017.09.031
TECHNICAL NOTE
Figure 3. Sagittal magnetic resonance imaging in case 3. A T2-weighed image (left) and heavy T2-weighted image (right) show that the dorsal
side of the spinal cord is dented at level Th2/3 (arrow), but it is unclear whether there is a cyst.
Figure 4. Sagittal magnetic resonance images of the cyst in case 4. A T2-weighed image (left) and heavy T2-weighted image (right) show that the
spinal cord is compressed from the dorsal side at level Th5/6, but it is unclear whether there is a cyst.
WORLD NEUROSURGERY 109: 18-23, JANUARY 2018
www.WORLDNEUROSURGERY.org
21
TECHNICAL NOTE
fractured plaques in carotid artery stenting. Stating in October 2016, we have used pyoktanin blue to enhance the visibility of arachnoid cysts. This use is based on the following properties:
Figure 5. Intraoperative findings in case 1. The cyst wall is unclear before injecting pyoktanin blue (upper). It became clear after staining with pyoktanin blue (lower).
Figure 6. Intraoperative findings in case 4. It is difficult to distinguish the cyst from the normal arachnoid space (A). Pyoktanin blue is injected into both spaces (B and D). Pyoktanin blue is stagnant 1 minute after injection in one of the
22
www.SCIENCEDIRECT.com
Safe excision. When pyoktanin blue is not used, the cyst border remains unclear, and the cyst often must be divided into several pieces, increasing the risk of retention of cyst residue and other complications. As mentioned above, the SAC can be easily excised as a lump after staining with pyoktanin blue. Distinguishing the cyst from the arachnoid membrane. Sometimes the entire cyst cannot be visualized because of an inadequate laminectomy or dural incision, even if the cyst border is noted. In such a situation, pyoktanin blue injection into the cyst and the subarachnoid space can be useful. If pyoktanin blue is injected into the cyst, the stain will stagnate; however, if it is injected into the subarachnoid space, it will be washed out. We used a more diluted pyoktanin blue solution to easily make observations. Avoiding unnecessary laminectomy or dural incision. Laminectomy or dural incision should be extended when it is not sufficient. Without any landmarks, superfluous procedures may be performed. Pyoktanin blue injection into the cyst can help avoid unnecessary laminectomy or dural incision. Yamaguchi et al.10 reported a technique for evaluating regional cerebrospinal fluid flow in focal arachnoid pathologies, such as an arachnoid web or adhesive arachnoiditis. In their study, they injected
spaces (C). It is washed out 1 minute after injection in the other space (E). The laminectomy and dural incision are extended with guidance from the staining of the cyst (F).
WORLD NEUROSURGERY, https://doi.org/10.1016/j.wneu.2017.09.031
TECHNICAL NOTE
gentian violet into the subarachnoid space to observe whether the intensity of the dye diminished, based on which they determined the range of arachnoid lysis. Their procedure was similar to ours but had a different focus. We emphasize that the goal of our procedure was not only to observe cerebrospinal fluid flow, but also to use the dye as a guide. We use pyoktanin blue at a concentration of 0.001%e0.002%, lower than that mentioned in previous reports.6-9 There have been no reports of complications or toxicities associated with the use of pyoktanin blue in the neurologic field, and there are no
REFERENCES 1. French H, Somasundaram A, Biggs M, Parkinson J, Allan R, Ball J, et al. Ideopathic intradural dorsal thoracic arachnoid cysts: a case series and review of the literature. J Clin Neurosci. 2017;40:147-152. 2. Woo JB, Son DW, Kang KT, Lee JS, Song GS, Sung SK, et al. Spinal extradural arachnoid cyst. Korean J Neurotrauma. 2016;12:185-190. 3. Nabors MW, Pait TG, Byrd EB, Karim NO, Davis DO, Kobrine AI, et al. Updated assessment and current classification of spinal meningeal cysts. J Neurosurg. 1988;68:366-377. 4. Choi SW, Seong HY, Roh SW. Spinal extradural arachnoid cyst. J Korean Neurosurg Soc. 2013;54: 355-358. 5. Lee CH, Hyun SJ, Kim KJ, Jahng TA, Kim HJ. What is a reasonable surgical procedure for spinal extradural arachnoid cysts: is cyst removal
contraindications according to the drug information; therefore, we believe that our technique is not harmful for patients. Our procedure has some limitations. Although our method makes it easy and safe to excise SACs, we used pyoktanin blue of a certain concentration. There may be a much better pyoktanin concentration for observing SACs.
CONCLUSION Our technique of using pyoktanin blue for visualizing SACs during surgery can help improve the ease and safety of cyst excision.
mandatory? Eight consecutive cases and a review of the literature. Acta Neurochir (Wien). 2012;154: 1219-1227. 6. Kamiyama H, Takahashi A, Houkin K, Mabuchi S, Abe H. Visualization of the ostium of an arteriotomy in bypass surgery. Neurosurgery. 1993;33: 1109-1110. 7. Hayashi N, Sasaki T, Tomura N, Okada H, Kuwata T. Removal of a malignant cystic brain tumor utilizing pyoktanin blue and fibrin glue: technical note. Surg Neurol Int. 2017;8:24.
10. Yamaguchi S, Hida K, Takeda M, Mitsuhara T, Morishige M, Yamada N, et al. Visualization of regional cerebrospinal fluid flow with a dye injection technique in focal arachnoid pathologies. J Neurosurg Spine. 2015;22:554-557.
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 31 July 2017; accepted 6 September 2017 8. Tomita Y, Sasaki T, Tanabe T, Idei M, Muraoka K, Terada K, et al. Pyoktanin blue injection for resection of cystic brain tumor: a case report. No Shinkei Geka. 2013;41:687-691 [in Japanese].
Citation: World Neurosurg. (2018) 109:18-23. https://doi.org/10.1016/j.wneu.2017.09.031 Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com
9. Nishido H, Hoya K, Kugasawa K, Iwakami T, Miyamoto S, Murakami M. Pyoktanin blue method for staining fractured plaques. J Neuroendovasc Ther. 2016;10:84-87.
WORLD NEUROSURGERY 109: 18-23, JANUARY 2018
1878-8750/$ - see front matter ª 2017 Elsevier Inc. All rights reserved.
www.WORLDNEUROSURGERY.org
23