Quantitative analysis of ipsilateral and contralateral supracerebellar infratentorial and occipital transtentorial approaches to the cisternal pulvinar: laboratory anatomical investigation

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OBJECTIVE

The cisternal pulvinar is a challenging location for neurosurgery. Four approaches for reaching the pulvinar without cortical transgression are the ipsilateral supracerebellar infratentorial (iSCIT), contralateral supracerebellar infratentorial (cSCIT), ipsilateral occipital transtentorial (iOCTT), and contralateral occipital transtentorial/falcine (cOCTF) approaches. This study quantitatively compared these approaches in terms of surgical exposure and maneuverability.

METHODS

Each of the 4 approaches was performed in 4 cadaveric heads (8 specimens in total). A 6-sided anatomical polygonal region was configured over the cisternal pulvinar, defined by 6 reachable anatomical points in different vectors. Multiple polygons were subsequently formed to calculate the areas of exposure. The surgical freedom of each approach was calculated as the maximum allowable working area at the proximal end of a probe, with the distal end fixed at the posterior pole of the pulvinar. Areas of exposure, surgical freedom, and the working distance (surgical depth) of all approaches were compared.

RESULTS

No significant difference was found among the 4 different approaches with regard to the surgical depth, surgical freedom, or medial exposure area of the pulvinar. In the pairwise comparison, the cSCIT approach provided a significantly larger lateral exposure (39 ± 9.8 mm2) than iSCIT (19 ± 10.3 mm2, p < 0.01), iOCTT (19 ± 8.2 mm2, p < 0.01), and cOCTF (28 ± 7.3 mm2, p = 0.02) approaches. The total exposure area with a cSCIT approach (75 ± 23.1 mm2) was significantly larger than with iOCTT (43 ± 16.4 mm2, p < 0.01) and iSCIT (40 ± 20.2 mm2, p = 0.01) approaches (pairwise, p ≤ 0.01).

CONCLUSIONS

The cSCIT approach is preferable among the 4 compared approaches, demonstrating better exposure to the cisternal pulvinar than ipsilateral approaches and a larger lateral exposure than the cOCTF approach. Both contralateral approaches described (cSCIT and cOCTF) provided enhanced lateral exposure to the pulvinar, while the cOCTF provided a larger exposure to the lateral portion of the pulvinar than the iOCTT. Medial exposure and maneuverability did not differ among the approaches. A short tentorium may negatively impact an ipsilateral approach because the cingulate isthmus and parahippocampal gyrus tend to protrude, in which case they can obstruct access to the cisternal pulvinar ipsilaterally.

ABBREVIATIONS BVR = basal vein of Rosenthal; cOCTF = contralateral occipital transtentorial/falcine; cSCIT = contralateral supracerebellar infratentorial; iOCTT = ipsilateral occipital transtentorial; IOV = internal occipital vein; iSCIT = ipsilateral supracerebellar infratentorial; OCTT = occipital transtentorial; PCA = posterior cerebral artery; SCIT = supracerebellar infratentorial.

Article Information

Correspondence Mark C. Preul: c/o Neuroscience Publications, Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center, Phoenix, AZ. neuropub@barrowneuro.org.

INCLUDE WHEN CITING Published online August 2, 2019; DOI: 10.3171/2019.4.JNS19351.

Q.S. and X.Z. contributed equally to this work and share first authorship.

Disclosures Dr. Sun acknowledges financial support from the China Scholarship Council.

© AANS, except where prohibited by US copyright law.

Headings

Figures

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    A: The trajectories for the iSCIT, cSCIT, iOCTT, and cOCTF approaches to the pulvinar. The head is placed in the prone position for occipital approaches. In the iOCTT approach, a 2-cm tentorial incision is made lateral to the straight sinus on the ipsilateral side. In the cOCTF approach, in addition to the tentorial incision made ipsilateral to the craniotomy, a 2.5-cm falcine incision is made superior to the straight sinus, with transection of the inferior sagittal sinus. The straight sinus can be mobilized either superiorly or inferiorly to offer inferior or superior trajectories, respectively. A sitting position is used to secure the head for supracerebellar approaches. B: Illustration of the measurement of the area of exposure from point M, the most posteriorly prominent point on the cisternal pulvinar. A 6-sided anatomical polygonal region (AC1C2BD2D1) is configured over the cisternal pulvinar. Point A is the superior reachable point and point B is the inferior reachable point on an imaginary line along the long axis of the pulvinar through point M. Points C1 and C2 are the superior and inferior reachable points on the lateral edge, respectively, and points D1 and D2 are the superior and inferior reachable points on the medial edge, respectively. The sum of the areas of the 6 triangles (AC1M, C1C2M, C2BM, BD2M, D2D1M, and D1AM) represents the total area of pulvinar exposure. The medial area of exposure is the sum of the areas of triangles AD1M, D1D2M, and D2BM (dotted area). The lateral area of exposure is the sum of the areas of triangles AC1M, C1C2M, and C2BM (hatched area). The superior area of exposure is the sum of the areas of triangles AC1M and AD1M (red). The inferior area of exposure is the sum of the areas of triangles BC2M and BD2M (green). P3 = third segment of the PCA; VOG = vein of Galen. Used with permission from Barrow Neurological Institute, Phoenix, Arizona. Figure is available in color online only.

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    Microscopic views demonstrating the exposures of the cisternal pulvinar for the iSCIT (A–C), iOCTT (D–F), cSCIT (G–I), and cOCTF (J–L) approaches. A: The left pulvinar is partly exposed in the iSCIT approach after retracting the left cerebellum. The left isthmus and posterior part of the parahippocampal gyrus herniate from the left tentorium edge and the surgical view is blocked from the posterior and lateral side. B: Under some superior retraction of the left isthmus and posterior part of parahippocampal gyrus, the pulvinar is partially exposed and the lateral view of the pulvinar is still limited. C: The left pulvinar is surrounded by the left P3, left IOV (yellow dashed lines), and left BVR that form a triangle (green area with asterisk) that can be a landmark for identifying the pulvinar. In this cadaver, the IOV is missing; thus, we used the yellow dashed line to approximate the missing IOV according to the literature. D: The left pulvinar is partly exposed in a left iOCTT approach after retracting the left occipital lobe. The left isthmus and posterior part of the parahippocampal gyrus still somewhat block the view in this approach even with the left tentorium incised. E: After retracting the left isthmus and posterior part of parahippocampal gyrus, the cisternal pulvinar has a better exposure. However, the lateral part of exposure to the pulvinar is still limited. F: The pulvinar is located in the triangle (green area with asterisk) formed by the P3, IOV, and BVR. G: The left pulvinar is exposed via a right cSCIT approach after retracting the right cerebellum. The cisternal pulvinar can be accessed from both the inferior-medial and superior-lateral side of the contralateral BVR via the cSCIT approach, which differs from the iSCIT approach because the contralateral trajectory can also maximally use the space inferior and medial to the BVR. H: After adjusting the working angle, the left pulvinar, especially the lateral portion, is easily accessed. A more lateral exposure can be obtained in the recess between the posterior surface of the pulvinar and the anterior surface of the cingulate isthmus and parahippocampal gyrus from a contralateral perspective. I: The pulvinar is located in the triangle (green area with asterisk) formed by the P3, IOV, and BVR. The isthmus or posterior part of the parahippocampal gyrus seldom blocks the surgical view. J: With the cOCTF approach, after cutting the tentorium, falx, and the transection of the inferior sagittal sinus, the straight sinus can be easily retracted inferiorly or superiorly. Thus, the inferior part of the cisternal pulvinar is accessed after retracting the straight sinus superiorly. K: The superior part of the pulvinar and splenium are exposed better if the straight sinus is retracted inferiorly. L: The pulvinar is noted by the triangle (green area with asterisk). bi. = bilateral; cer. = cerebral; Cing. = cingulate; coll. = colliculus; Inf. = inferior; Int. = internal; g. = gland; L. = left; occip. = occipital; Par. = parietal; parahipp. gyr. = parahippocampal gyrus; R. = right; Str. = straight; Sup. = superior; Tent. = tentorium; trans. = transverse; v. = vein; ve. = vermian. Used with permission from Barrow Neurological Institute, Phoenix, Arizona. Figure is available in color online only.

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    Illustration of the measurement of surgical freedom, the most posteriorly prominent point on the cisternal pulvinar, defined as the maximum allowable working area (mm2) at the proximal end of the 190-mm probe, with the distal end on point M, the midpoint of the pulvinar. The movement of the probe shaft can be limited by the corner of the rectangular bone window or any structure precluding further movement of the probe. Differences in surgical freedom from point M did not differ significantly among the 4 approaches.

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    Case 1. Illustrative case in which the iSCIT approach was used. Preoperative MRI—axial T1-weighted with contrast (A), axial T2-weighted (B), and coronal T1-weighted with contrast (C)—shows prior thalamic hemorrhage and a left posteromedial thalamic cavernous malformation in the medial pulvinar in a 19-year-old man. The trajectory of the iSCIT approach is shown by the white arrow (panel C). Intraoperative photograph (D) shows the intracapsular technique used for piecemeal resection of the cavernous malformation. Postoperative axial T1-weighted (E) and coronal with contrast (F) MRI demonstrate complete resection of the cavernous malformation. Panel D used with permission from Barrow Neurological Institute, Phoenix, Arizona. Figure is available in color online only.

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    Case 2. Illustrative case in which the cSCIT approach was used. Preoperative MRI—axial T1-weighted without contrast (A), axial T2-weighted without contrast (B), sagittal T1-weighted without contrast (C), and coronal T2-weighted without contrast (D)—shows a new symptomatic hemorrhage in a 71-year-old man with a known left thalamic cavernous malformation. Trajectory of the cSCIT approach is shown by the red and white arrows (panels B and D, respectively). Intraoperative photograph (E) shows microsurgical dissection continued all the way to the galenic complex. The pulvinar is accessed medial to the basal vein and the cavernous malformation is resected piecemeal by using an intracapsular technique. After the malformation was peeled away from the thalamus, no remnant was seen (F). Postoperative MRI—axial T2-weighted without contrast (G), sagittal T1-weighted without contrast (H), and coronal T2-weighted without contrast (I)—demonstrates complete resection of the cavernous malformations. Panels E and F used with permission from Barrow Neurological Institute, Phoenix, Arizona. Figure is available in color online only.

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    A special case in which the tentorium is very short; thus, the cingulate isthmus and posterior part of the parahippocampal gyrus extend over the tentorial edge to the infratentorial cistern. A: The right cisternal pulvinar is totally blocked by the herniated parahippocampal gyrus with the right cerebellum retracted in an iSCIT approach. B: The right pulvinar is exposed easily via the cSCIT approach after the left cerebellum is retracted gently. The right parahippocampal gyrus or isthmus is not blocking the surgical view. Cing. = cingulate; Inf. = inferior; L. = left; Occip. = occipital; parahipp. gyr. = parahippocampal gyrus; R. = right; Sup. = superior; Tent. = tentorium; Trans. = transverse; v. = vein. Used with permission from Barrow Neurological Institute, Phoenix, Arizona. Figure is available in color online only.

References

  • 1

    Abla AASpetzler RF: Cavernous malformations of the thalamus: a relatively rare but controversial entity. World Neurosurg 79:6416442013

  • 2

    Akiyama OMatsushima KGungor AMatsuo SGoodrich DJTubbs RS: Microsurgical and endoscopic approaches to the pulvinar. J Neurosurg 127:6306452017

  • 3

    Belykh EOnaka NRZhao XCavallo CYağmurlu KLei T: Endoscopically assisted targeted keyhole retrosigmoid approaches for microvascular decompression: quantitative anatomic study. World Neurosurg 119:e1e152018

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 4

    Cohen-Cohen SCohen-Gadol AAGomez-Amador JLAlves-Belo JTShah KJFernandez-Miranda JC: Supracerebellar infratentorial and occipital transtentorial approaches to the pulvinar: ipsilateral versus contralateral corridors. Oper Neurosurg (Hagerstown) 16:3513592019

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 5

    Erbaş GOner AYAkpek STokgoz N: Corpus callosum hematoma secondary to isolated inferior sagittal sinus thrombosis. Acta Radiol 47:108510882006

  • 6

    Gunnarut IBurkhardt JKNeidert MCBozinov O: Endoscopic and gravity-assisted resection of medial temporo-occipital lesions through a supracerebellar transtentorial approach: technical notes with case illustrations. Oper Neurosurg (Hagerstown) 13:E541E5422017

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 7

    Ishii RSuzuki YWatanabe AMouri YIshii NYoshii I: Gross total removal of gliomas in the pulvinar and correlative microsurgical anatomy. Neurol Med Chir (Tokyo) 42:5365462002

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 8

    Iwami KFujii MSaito K: Occipital transtentorial/falcine approach, a “cross-court” trajectory to accessing contralateral posterior thalamic lesions: case report. J Neurosurg 127:1651702017

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 9

    Jittapiromsak PDeshmukh PNakaji PSpetzler RFPreul MC: Comparative analysis of posterior approaches to the medial temporal region: supracerebellar transtentorial versus occipital transtentorial. Neurosurgery 64 (3 Suppl):ons35ons432009

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 10

    Kawashima MRhoton AL JrMatsushima T: Comparison of posterior approaches to the posterior incisural space: microsurgical anatomy and proposal of a new method, the occipital bi-transtentorial/falcine approach. Neurosurgery 51:120812212002

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 11

    Mascitelli JBurkhardt JKGandhi SLawton MT: Contralateral supracerebellar-infratentorial approach for resection of thalamic cavernous malformations. Oper Neurosurg (Hagerstown) 15:4044112018

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 12

    Ono MOno MRhoton AL JrBarry M: Microsurgical anatomy of the region of the tentorial incisura. J Neurosurg 60:3653991984

  • 13

    Rangel-Castilla LSpetzler RF: The 6 thalamic regions: surgical approaches to thalamic cavernous malformations, operative results, and clinical outcomes. J Neurosurg 123:6766852015

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 14

    Shin HJCho BKJung HWWang KC: Pediatric pineal tumors: need for a direct surgical approach and complications of the occipital transtentorial approach. Childs Nerv Syst 14:1741781998

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 15

    Solomon RAStein BM: Interhemispheric approach for the surgical removal of thalamocaudate arteriovenous malformations. J Neurosurg 66:3453511987

  • 16

    Steiger HJGötz CSchmid-Elsaesser RStummer W: Thalamic astrocytomas: surgical anatomy and results of a pilot series using maximum microsurgical removal. Acta Neurochir (Wien) 142:132713372000

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 17

    Yamada KMase MMatsumoto T: Surgery for deeply seated arteriovenous malformation: with special reference to thalamic and striatal arteriovenous malformation. Neurol Med Chir (Tokyo) 38 (Suppl):2272301998

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 18

    Yaşargil MG: Microneurosurgery Vol I. Microsurgical Anatomy of the Basal Cisterns and Vessels of the Brain Diagnostic Studies General Operative Techniques and Pathological Considerations of the Intracranial Aneurysms. Stuttgart: Georg Thieme1984

    • Search Google Scholar
    • Export Citation

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