Comparative analysis of posterior approaches to the medial temporal region: supracerebellar transtentorial versus occipital transtentorial.
OBJECTIVE
Cortical and subcortical lesions in the posterior portion of the medial temporal region (MTR) are routinely resected through the supracerebellar transtentorial (SCTT) or occipital transtentorial (OCTT) route. We compared the exposures provided by these 2 approaches to this region.


METHODS
Eight sides of injected cadaver heads were dissected using both approaches. Identical deep target points were collected for SCTT and OCTT routes while accepting variations in initial exposures. Data gathered with the P2-P3 junction as an apex created 2 adjoining triangles (anterior and posterior) in the middle and posterior MTR. Real, projected, and freedom areas were calculated for comparison.


RESULTS
The approach-related differences for the real and projected areas were expressed in relative values. There were no differences in the percentage of projected area between the 2 approaches (e.g., working in the middle of the opening, anterior triangle: SCTT, 5.2 +/- 4.1%; OCTT, 8.4 +/- 5.6%; P = 0.313; posterior triangle: SCTT, 8.6 +/- 3.8%; OCTT, 8.8 +/- 6.3%; P = 0.937). Freedom areas for the SCTT approach were smaller than those for the OCTT approach at many deep points (P < 0.05), except in the posterior margin of the MTR (P = 0.21).


CONCLUSIONS
The SCTT and OCTT approaches provided no differences in surgical views to the MTR. However, the OCTT approach provides a wider corridor for surgical manipulation compared with the SCTT approach in most parts of the MTR. These data may help neurosurgeons to select a favorable approach to specific lesions of the MTR.
Jittapiromsak
Pakrit
P
Division of Neurological Surgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.
Deshmukh
Pushpa
P
Nakaji
Peter
P
Spetzler
Robert F
RF
Preul
Mark C
MC
D002102:Cadaver; D002531:Cerebellum / Q000033:anatomy & histology* / Q000601:surgery*; D003627:Data Interpretation, Statistical; D004210:Dissection; D006801:Humans; D019635:Neurosurgical Procedures / Q000379:methods*; D009778:Occipital Lobe / Q000033:anatomy & histology* / Q000601:surgery*; D012886:Skull / Q000033:anatomy & histology / Q000601:surgery; D013702:Temporal Lobe / Q000033:anatomy & histology* / Q000601:surgery*