Table 1.
Nomenclature of Transbasal Approaches Reported in the Literature Categorized According to Proposed Classification of Transbasal Approaches
| Transbasal Approach | Level I Transbasal Approach | Level II Transbasal Approach | Level III Transbasal Approach |
|---|---|---|---|
| Transbasal approach13,26,27,28 | Sub-basal approach29 | Extended anterior subcranial approach, type B20 | Telecanthal approach30 |
| Standard subfrontal approach31 | Enlarged transbasal approach32 | Extended transbasal approach17,31 | Radical transbasal approach33 |
| Extradural transbasal approach34 | Supraorbital approach35 | Telecanthal approach30 | Level III transfacial approach1 |
| Frontal transbasal approach36 | Transfrontal approach1 | Extended subcranial approach, type B37 | Transglabellar subcranial approach with extended frontonasal flap38 |
| Transfrontal extradural approach39 | Transbasal approach31 | Transfrontal basal approach40 | Transfrontonasal orbital approach1 |
| Standard transbasal approach41 | Extended frontal approach42 | Transbasal anterior approach40 | Intracranial route A3 procedure5 |
| Traditional transbasal approach43 | Extended subfrontal approach44,45 | Level II transfacial approach1 | – |
| Classic transbasal approach, type 1, subtypes A–C2 | Subcranial approach46 | – | |
| Supraorbital subfrontal approach*,47 | Transglabellar subcranial approach with frontonasal flap38 | – | |
| Bifrontal transbasal approach48 | Extensive subfrontal approach49 | Transfrontonasal approach1 | – |
| Transfrontal approach50 | Extensive transbasal approach51,52 | Subcranial approach46 | – |
| – | Fronto-orbital ridge deposition (FORD) approach26 | Intracranial routes A1–2 procedures7 | – |
| – | Transfrontonaso-orbital approach53 | Anterior craniofacial approach18 | – |
| – | Bifrontal biorbital sphenoethmoidal approach54 | – | – |
| – | Level I transfacial approach1 | – | – |
| – | Subfrontal basal approach†,50 | – | – |
| – | Subfrontal approach55 | – | – |
| – | Trans-sinusal frontal approach56 | – | – |
| – | Versatile frontal sinus approach57 | – | – |
| – | Supraorbital rim approach58 | – | – |
| – | Midline supraorbital approach59 | – | – |
| – | Extended transbasal approach23,43,60,61 | – | – |
| – | Transbasal approach, type II, subtypes A–C2 | – | – |
| – | Transbasal approach, type III, subtypes A–C2 | – | – |
| – | Frontal transbasal approach19 | – | – |
| – | Supraorbital subfrontal approach*,47 | – | – |
*
Based on the technique described by Obeid and Al-Mefty,47 it is unclear whether an orbital bar osteotomy is applied preventing a clear categorization to transbasal or level I.
†
Based on technical description by Delfini et al,53 the status of the medial canthal ligaments cannot be defined, preventing a clear categorization to level I or II. However, based on personal communications (Spetzler, Delfini, unpublished data) status of medial canthal ligaments was elucidated.