{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T00:19:07Z","timestamp":1790381947797,"version":"4.1.0"},"reference-count":29,"publisher":"Journal of Neurosurgery Publishing Group (JNSPG)","issue":"5","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2024,5,1]]},"abstract":"<jats:sec>\n<jats:title>OBJECTIVE<\/jats:title>\n<jats:p>In the authors\u2019 microsurgical experience, the trans\u2013middle cerebellar peduncle (MCP) approach to the lateral and central pons has been the most common approach to brainstem cavernous malformations (BSCMs). This approach through a well-tolerated safe entry zone (SEZ) allows a wide vertical or posterior trajectory, reaching pontine lesions extending into the midbrain, medulla, and pontine tegmentum. Better understanding of the relationships among lesion location, surgical trajectory, and long-term clinical outcomes could determine areas of safe passage.<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title>METHODS<\/jats:title>\n<jats:p>A single-surgeon cohort study of all primary trans-MCP BSCM resections was conducted from July 1, 2017, to June 30, 2021. Preoperative and postoperative MR images were independently reviewed by 3 investigators blinded to the intervention, using a standardized rubric to define BSCM regions of interest (ROIs) involved with a lesion or microsurgical tract. Statistical testing, including the chi-square test with the Bonferroni correction, logistic regression, and structural equation modeling, was performed to analyze relationships between ROIs and clinical outcomes.<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title>RESULTS<\/jats:title>\n<jats:p>Thirty-one patients underwent primary trans-MCP BSCM resection during the study period. The median age was 50 years (IQR 24\u201349 years); 19 (61%) patients were female, and 12 (39%) were male. Seven (23%) patients had familial cavernous malformation syndromes. The median follow-up was 9 months (range 6\u201337 months). At the last follow-up, composite neurological outcomes were favorable: 22 (71%) patients had 0 (n = 12, 39%) or 1 (n = 10, 32%) major persistent deficit, 5 patients (16%) had 2 deficits, 2 (7%) had 3 deficits, and 1 patient each (3%) had 4 or 6 deficits. Unfavorable composite outcomes were significantly associated with lesions (OR 7.14, p = 0.04) or surgical tracts (OR 12.18, p &lt; 0.001) extending from the superior cerebellar peduncle (SCP) into the contralateral medial midbrain. The ipsilateral dorsal pons was the most frequently implicated ROI involving a surgical tract and the development of new postoperative deficits. This region involved the rhomboid pontine territory and transgression of the pontine tegmentum (OR 7.53, p &lt; 0.001). Structural equation modeling supported medial midbrain and pontine tegmentum transgression as the primary drivers of morbidity.<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title>CONCLUSIONS<\/jats:title>\n<jats:p>Trans-MCP resection is a safe and effective treatment for BSCMs, including lesions with marked superior or inferior ipsilateral extension. Two trajectories are associated with increased neurological risk: first, a superomedial trajectory to lesions extending into the midbrain that transgresses the SCP, its decussation, or both; and second, a posteromedial trajectory to lesions extending into the pontine tegmentum. The corticospinal tract, SCP, and pontine tegmentum form an invisible triangle within the pontine white matter tolerant of transgression. When the surgeon works within this triangle, most deep pontine BSCMs, including large lesions, those with contralateral or posterior extension, and others extending into the midbrain and medulla, can be resected safely with the trans-MCP approach.<\/jats:p>\n<\/jats:sec>","DOI":"10.3171\/2023.8.jns231684","type":"journal-article","created":{"date-parts":[[2023,11,18]],"date-time":"2023-11-18T01:27:25Z","timestamp":1700270845000},"page":"1344-1356","source":"Crossref","is-referenced-by-count":6,"title":["Expanding the reach of the trans\u2013middle cerebellar peduncle approach: pontine cavernous malformations, tissue transgression beyond the safe entry zone, and the invisible triangle"],"prefix":"10.3171","volume":"140","author":[{"given":"Christopher S.","family":"Graffeo","sequence":"first","affiliation":[{"name":"Department of Neurosurgery, Barrow Neurological Institute, St. Joseph\u2019s Hospital and Medical Center, Phoenix, Arizona"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Visish M.","family":"Srinivasan","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Barrow Neurological Institute, St. Joseph\u2019s Hospital and Medical Center, Phoenix, Arizona"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lea","family":"Scherschinski","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Barrow Neurological Institute, St. Joseph\u2019s Hospital and Medical Center, Phoenix, Arizona"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dimitri","family":"Benner","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Barrow Neurological Institute, St. Joseph\u2019s Hospital and Medical Center, Phoenix, Arizona"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katherine","family":"Karahalios","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Barrow Neurological Institute, St. Joseph\u2019s Hospital and Medical Center, Phoenix, Arizona"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Diego A.","family":"Devia","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Barrow Neurological Institute, St. Joseph\u2019s Hospital and Medical Center, Phoenix, Arizona"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joshua S.","family":"Catapano","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Barrow Neurological Institute, St. Joseph\u2019s Hospital and Medical Center, Phoenix, Arizona"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael T.","family":"Lawton","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Barrow Neurological Institute, St. Joseph\u2019s Hospital and Medical Center, Phoenix, Arizona"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1754","reference":[{"issue":"3","key":"b1","series-title":"J Neurosurg","first-page":"671","article-title":"Recurrent brainstem cavernous malformations following primary resection: blind spots, fine lines, and the right-angle method","volume":"135","author":"Garcia RM","year":"2020","unstructured":"Garcia RM, Oh T, Cole TS, Hendricks BK, Lawton MT. Recurrent brainstem cavernous malformations following primary resection: blind spots, fine lines, and the right-angle method. J Neurosurg. 2020;135(3):671\u2013682."},{"issue":"1-2","key":"b2","series-title":"World Neurosurg","first-page":"89","article-title":"Brainstem cavernous malformations: 1390 surgical cases from the literature","volume":"80","author":"Gross BA","year":"2013","unstructured":"Gross BA, Batjer HH, Awad IA, Bendok BR, Du R. Brainstem cavernous malformations: 1390 surgical cases from the literature. World Neurosurg. 2013;80(1-2):89\u201393."},{"issue":"5","key":"b3","series-title":"Neurosurgery","first-page":"E805","article-title":"Brainstem cavernous malformations","volume":"64","author":"Gross BA","year":"2009","unstructured":"Gross BA, Batjer HH, Awad IA, Bendok BR. Brainstem cavernous malformations. Neurosurgery. 2009;64(5):E805\u2013E818."},{"issue":"1-2","key":"b4","series-title":"World Neurosurg","first-page":"44","article-title":"Brainstem cavernoma surgery: the state of the art","volume":"80","author":"Abla AA","year":"2013","unstructured":"Abla AA, Spetzler RF. Brainstem cavernoma surgery: the state of the art. World Neurosurg. 2013;80(1-2):44\u201346."},{"issue":"5","key":"b5","series-title":"J Neurosurg","first-page":"1231","article-title":"External validation of the Lawton brainstem cavernous malformation grading system in a cohort of 277 microsurgical patients","volume":"136","author":"Catapano JS","year":"2021","unstructured":"Catapano JS, Rutledge C, Rumalla K,  External validation of the Lawton brainstem cavernous malformation grading system in a cohort of 277 microsurgical patients. J Neurosurg. 2021;136(5):1231\u20131239."},{"issue":"3","key":"b6","series-title":"Neurosurgery","first-page":"265","article-title":"Brainstem cavernous malformations: surgical results in 104 patients and a proposed grading system to predict neurological outcomes","volume":"76","author":"Garcia RM","year":"2015","unstructured":"Garcia RM, Ivan ME, Lawton MT. Brainstem cavernous malformations: surgical results in 104 patients and a proposed grading system to predict neurological outcomes. Neurosurgery. 2015;76(3):265\u2013278."},{"issue":"5","key":"b7","series-title":"J Neurosurg","first-page":"1409","article-title":"The future of open vascular neurosurgery: perspectives on cavernous malformations, AVMs, and bypasses for complex aneurysms","volume":"130","author":"Lawton MT","year":"2019","unstructured":"Lawton MT, Lang MJ. The future of open vascular neurosurgery: perspectives on cavernous malformations, AVMs, and bypasses for complex aneurysms. J Neurosurg. 2019;130(5):1409\u20131425."},{"issue":"10","key":"b8","series-title":"Neurology","first-page":"881","article-title":"The unruptured intracranial aneurysm treatment score: a multidisciplinary consensus","volume":"85","author":"Etminan N","year":"2015","unstructured":"Etminan N, Brown RD Jr, Beseoglu K,  The unruptured intracranial aneurysm treatment score: a multidisciplinary consensus. Neurology. 2015;85(10):881\u2013889."},{"issue":"5","key":"b9","series-title":"J Neurosurg","first-page":"1462","article-title":"A taxonomy for brainstem cavernous malformations: subtypes of pontine lesions. Part 1: basilar, peritrigeminal, and middle peduncular","volume":"137","author":"Catapano JS","year":"2022","unstructured":"Catapano JS, Rumalla K, Srinivasan VM,  A taxonomy for brainstem cavernous malformations: subtypes of pontine lesions. Part 1: basilar, peritrigeminal, and middle peduncular. 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World Neurosurg. 2022;158:e64\u2013e74."},{"issue":"S01","key":"b12","series-title":"J Neurol Surg B Skull Base","first-page":"P158","article-title":"Volumetric three-dimensional analysis of the retrosigmoid, extended retrosigmoid, and presigmoid-retrolabyrinthine transpetrosal fissure approaches to the middle cerebellar peduncle","volume":"83","author":"Abramov I","year":"2022","unstructured":"Abramov I, Labib MA, Houlihan LM,  Volumetric three-dimensional analysis of the retrosigmoid, extended retrosigmoid, and presigmoid-retrolabyrinthine transpetrosal fissure approaches to the middle cerebellar peduncle. J Neurol Surg B Skull Base. 2022;83(S01):P158."},{"issue":"6","key":"b13","series-title":"J Neurosurg","first-page":"1667","article-title":"A taxonomy for brainstem cavernous malformations: subtypes of midbrain lesions","volume":"136","author":"Catapano JS","year":"2021","unstructured":"Catapano JS, Rumalla K, Srinivasan VM, Lawrence PM, Larson Keil K, Lawton MT. 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World Neurosurg. 2016;87:235\u2013241."},{"issue":"3","key":"b17","series-title":"Acta Neurochir (Wien)","first-page":"763","article-title":"How I do it: horizontal fissure approach to the middle cerebellar peduncle","volume":"164","author":"Rutledge C","year":"2022","unstructured":"Rutledge C, Tonetti DA, Raygor KP, Abla AA. How I do it: horizontal fissure approach to the middle cerebellar peduncle. Acta Neurochir (Wien). 2022;164(3):763\u2013766."},{"issue":"3","key":"b18","series-title":"J Neurosurg","first-page":"768","article-title":"A system of anatomical triangles defining dissection routes to brainstem cavernous malformations: definitions and application to a cohort of 183 patients","volume":"138","author":"Benner D","year":"2022","unstructured":"Benner D, Hendricks BK, Benet A,  A system of anatomical triangles defining dissection routes to brainstem cavernous malformations: definitions and application to a cohort of 183 patients. J Neurosurg. 2022;138(3):768\u2013784."},{"issue":"1","key":"b19","series-title":"J Neurosurg","first-page":"128","article-title":"A taxonomy for brainstem cavernous malformations: subtypes of medullary lesions","volume":"138","author":"Catapano JS","year":"2022","unstructured":"Catapano JS, Rumalla K, Srinivasan VM, Lawrence PM, Larson Keil K, Lawton MT. A taxonomy for brainstem cavernous malformations: subtypes of medullary lesions. J Neurosurg. 2022;138(1):128\u2013146."},{"issue":"3 Suppl Operative","key":"b20","series-title":"Neurosurgery","first-page":"26","article-title":"Lateral transpeduncular approach to intrinsic lesions of the rostral pons","volume":"66","author":"Hebb MO","year":"2010","unstructured":"Hebb MO, Spetzler RF. Lateral transpeduncular approach to intrinsic lesions of the rostral pons. Neurosurgery. 2010;66(3 Suppl Operative):26\u201329."},{"issue":"6 Suppl Operative","key":"b21","series-title":"Neurosurgery","first-page":"306","article-title":"Retrosigmoid suprafloccular transhorizontal fissure approach for resection of brainstem cavernous malformation","volume":"66","author":"Ohue S","year":"2010","unstructured":"Ohue S, Fukushima T, Friedman AH,  Retrosigmoid suprafloccular transhorizontal fissure approach for resection of brainstem cavernous malformation. Neurosurgery. 2010;66(6 Suppl Operative):306\u2013313."},{"issue":"4 suppl 2","key":"b22","series-title":"Neurosurgery","first-page":"ONS-208-ONS","article-title":"The extended retrosigmoid approach: an alternative to radical cranial base approaches for posterior fossa lesions","volume":"58","author":"Qui\u00f1ones-Hinojosa A","year":"2006","unstructured":"Qui\u00f1ones-Hinojosa A, Chang EF, Lawton MT. The extended retrosigmoid approach: an alternative to radical cranial base approaches for posterior fossa lesions. Neurosurgery. 2006;58(4 suppl 2):ONS-208-ONS\u2013214."},{"issue":"1","key":"b23","series-title":"Neurosurgery","first-page":"58","article-title":"Microsurgical anatomy of the posterior fossa cisterns","volume":"23","author":"Matsuno H","year":"1988","unstructured":"Matsuno H, Rhoton AL Jr, Peace D. Microsurgical anatomy of the posterior fossa cisterns. Neurosurgery. 1988;23(1):58\u201380."},{"issue":"3)(suppl","key":"b24","series-title":"Neurosurgery","first-page":"S7","article-title":"Cerebellum and fourth ventricle","volume":"47","author":"Rhoton AL Jr","year":"2000","unstructured":"Rhoton AL Jr. Cerebellum and fourth ventricle. Neurosurgery. 2000;47(3)(suppl):S7\u2013S27."},{"issue":"5","key":"b25","series-title":"J Neurosurg","first-page":"1554","article-title":"Complex cranial surgery and the future of open cerebrovascular training","volume":"137","author":"Graffeo CS","year":"2022","unstructured":"Graffeo CS, Link MJ, Lawton MT. Complex cranial surgery and the future of open cerebrovascular training. J Neurosurg. 2022;137(5):1554\u20131561."},{"key":"b26","series-title":"Clin Neurosurg","first-page":"36","article-title":"Discovering the novel surgical approach","volume":"50","author":"Clatterbuck RE","year":"2003","unstructured":"Clatterbuck RE, Bernardo A, Spetzler RF. Discovering the novel surgical approach. Clin Neurosurg. 2003;50:36\u201344."},{"issue":"1","key":"b27","series-title":"Barrow Q","first-page":"2","article-title":"The two-point method: evaluating brain stem lesions","volume":"12","author":"Brown AP","year":"1996","unstructured":"Brown AP, Thompson BG, Spetzler RF. 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