Table 1.
Intracranial DAVFs complicated with brainstem engorgement.
| No. | Author/year | Age/sex | Presentation/interval to definite diagnosis | Initial misdiagnosis | DAVF location | Concurrent with venous sinus stenosis/occlusion | Signal alteration on MRI | Region of congestion | Feeding artery | Draining vein | Cognard classification | Treatment | Degree of DAVF obliteration | Follow-up period | Retreatment | Outcome (mRS) | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| T1, T1 C+ | T2 | FLAIR | DWI, ADC | Abnormal vascular flow-void | ||||||||||||||||
| 1 | Probst et al. (5) | 40/F | Headache, nausea, and dnormalrientation/ NA/NM | Yes (brain tumor) | TS | Yes | NA/NM, inhomogeneous enhancement | Hyper | NA/NM | NA/NM, NA/NM | Yes | Pons, cerebellum, and thalamus | OA and branches of the ICA | Straight sinus → vein of Galen → pontomesencephalic vein → vein of Rosenthal | Type V | Endovascular + surgical | Completely | NA/NM | No | 0 |
| 2 | Uchino et al. (6) | 68/F | Gait disturbance, dysarthria, and urinary incontinence/4 years | No | CS | Yes | Hypo, enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Pons | Branches of ECA and ICA | Vein of Rosenthal, inferior anastomotic vein of Labbe, pontine venous congestion | Type IIB | Subtotal TAE of ECA branches with polyvinyl alcohol particles | Incompletely | 2 years | No | 5 |
| 3 | 74/M | Chemosis, proptosis, and gait disturbance/ NA/NM | No | CS | Yes | Hypo, enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Pons and cerebellum | Branches of ECA and ICA | Cortical veins of the posterior fossa, pontine venous congestion | Type IIA+B | Subtotal TAE of ECA branches with polyvinyl alcohol particles | Incompletely | 4 months | No | 2 | |
| 4 | Ernst et al. (7) | 71/M | Paraparesis, nausea, and vomiting/ NA/NM | No | SPS | No | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | Yes | Hypoer medulla oblongata extending to the upper cervical cord | MHT of the ICA | PMV | Type V | Open surgery | Completely | 18 months | No | 1 |
| 5 | 58/F | Tetrapraresis/many years | No | CCJ | No | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the entire cervical cord | Ascending cervical artery of ECA, VA, ophthalmic artery | PMV | Type V | TAE with PVA and silk thread | Incompletely | 4 years | No | 4 or 5 | |
| 6 | Chen et al. (2) | 47/M | Tetrapareis, paresthesia, urinary retention/1 year | No | Torcular | No | NA/NM, NA/NM | NA/NM | NA/NM | NA/NM, NA/NM | Yes | Hypoer medulla oblongata extending to the upper cervical cord | Meningeal branch of the VA | Cerebellar vein → veins of the hypoer brainstem → PMV | Type V | Open surgery | Completely | 2 months | No | 4 or 5 |
| 7 | Ricolfi et al. (8) | 53/M | Paraparesis, paresthesia, urinary retention/several months | No | Tentorium | No | Hypo, non-enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Hypoer medulla oblongata extending to the upper cervical cord | MHT of the ICA, MMA | Lateral pontomesencephalic veins → cervical and thoracic PMV | Type V | TAE with NBCA via MMA and occluding ICA | Incompletely | 2 years | Yes/ coagulated the draining veins | 1 or 2 |
| 8 | 40/F | Tetrapareis, sphincter disturbance, bulbar signs/1 year | No | CS | No | Hypo, non-enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Hypoer medulla oblongata extending to the upper cervical cord | MHT of the ICA, MMA, sphenopalatine artery and AphA | Superior ophthalmic vein and SPS → lateral mesencephalic veins → PMV | Type V | TAE with NBCA via MMA and sphenopalatine arteries, with PVA particles via APhA | Completely | 5 days | No | Dead | |
| 9 | 75/M | Tetraplegia, sphincter disturbance, bulbar signs, dysautonomia/a few days | No | SPS | Yes | Hypo, non-enhanced | Hyper | NA/NM | NA/NM, NA/NM | No | Hypoer pons and medulla oblongata extending to the upper cervical cord | MMA | PMV | Type V | TAE with NBCA via MMA | Completely | 5 years | No | 0 | |
| 10 | 51/F | Paraparesis, sphincter disturbance, bulbar signs, dysautonomia/3 months | Yes (initial negative) | SS | Yes | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the upper cervical cord | OA, MMA | Lateral medullary vein → PMV | Type V | TAE with NBCA via MMA and OA | Completely | 1 year | No | 0 | |
| 11 | Bousson et al. (9) | 36/M | Tetrapraresis, paresthesia/4 months | No | Tentorium | No | NA/NM, intensely enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the entire cervical cord | OA | Vein around brainstem → PMV | Type V | TAE to occlude the OA | Incompletely | 2 weeks | No | NA/NM |
| 12 | Hurst et al. (10) | 54/M | Tetrapraresis/ NA/NM | No | CCJ | No | NA/NM, enhanced | Hyper | NA/NM | NA/NM/ NA/NM | Yes | Hypoer medulla oblongata extending to the upper cervical cord | Dural branch of VA | PMV | Type V | TAE with PVA via the dural branch of VA | Completely | 3 months | No | 3 |
| 13 | 50/M | Tetrapraresis, pain, hypoer CN deficits/ NA/NM | No | CCJ | No | Hypo/ NA/NM | Hyper | NA/NM | NA/NM/ NA/NM | Yes | Hypoer medulla oblongata extending to the upper cervical cord | AphA | PMV | Type V | TAE with polyvinyl alcohol via APhA | Completely | 12 months | No | 4 | |
| 14 | Takahashi et al. (11) | 49/M | Diplopia, vertigo/3 weeks | No | CS | Yes | Hypo, enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Pons and cerebellar hemisphere | MHT of the ICA | SPS → ophthalmic vein, petrosal vein → cortical venous reflux | Type IIA+B | TVE with coils | Completely | 3 months | No | 0 or 1 |
| 15 | 62/F | Loss of visual acuity, chemosis, exophthalmos/ NA/NM | No | CS | No | Hypo, markedly enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Pons and medulla oblongata | Branches of bilateral ECA and ICA | CS → superior ophthalmic vein | Type IIA+B | TVE with coils | Completely | 1 month | No | 2 | |
| 16 | Shintani et al. (12) | 65/F | Chemosis, CN (III, IV, VI) palsy, vertigo/8 months | No | CS | No | Hypo, markedly enhanced | Hyper | NA/NM | NA/NM, NA/NM | No | Pons | Branches of ICA | IPS | NA/NM | NA/NM | NA/NM | NA/NM | NA/NM | Dead |
| 17 | Wiesmann et al. (13) | 46/M | Paraparesis, dysarthria, urinary incontinence/4 days | No | CCJ | Yes | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | No | Pontomedullary region | NMB of AphA | Anterior median pontine and anterior medullary veins → anterior and posterior spinal veins | Type V | TAE with NBCA via AphA | Completely | 12 months | No | 1 |
| 18 | Kalamangalam et al. (14) | 68/M | Paraparesis, urinary incontinence/4 months | Yes (stroke) | CCJ (Clivus) | No | Normal, non-enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Hypoer medulla oblongata extending to the entire cervical cord | MHT of the ICA | Veins around brainstem → PMV of cervical spinal cord | Type V | Surgical clipping draining vein | Completely | 4 months | No | 3 |
| 19 | Weigele et al. (15) | 53/M | Cranial neuropathies, hemidysesthesia, and personality changes/several months | Yes (brainstem glioma) | Galen vein | No | Normal, non-enhanced | Hyper | Hyper | NA/NM, NA/NM | Yes | Pons, midbrain, and thalamus | MMA, NMB of AphA, marginal artery, vermin branch of SCA | Pontomedullary and anterior cortical veins → superior sagittal sinus | Type IV | TAE with NBCA via MMA and AphA | Completely | 6 months | No | 0 |
| 20 | Asakawa et al. (16) | 64/M | Tetrapraresis, urinary incontinence, respiratory insufficiency/2 weeks | No | CCJ (foramen magnum) | No | Hypo, enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Hypoer medulla oblongata extending to the upper thoracic cord | AphA | Spinal veins | Type V | Combined TAE and surgical interruption | Completely | 3 months | No | 4 |
| 21 | Lanz et al. (17) | 68/F | Diplopia, dysarthria, syncope, transient Paraparesis, respiratory insufficiency/1 year | No | SS | Yes | Normal, non-enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the upper cervical cord | MMA | SS → vein around brainstem → PMV | Type V | TAE with NBCA via MMA | Completely | NM | No | 0 |
| 22 | Kai et al. (18) | 56/F | Proptosis, double vision, visual disturbance, hemiparesis/2 weeks | No | CS | No | NA/NM, moderately enhanced | Hyper | NA/NM | NA/NM, NA/NM | No | Brainstem | Branches of the ECA | Petrosal vein → cerebellar veins | Type IIA+B | TVE via petrosal vein cannulation with coils | Incompletely | 1 month | No | 3 |
| 23 | 70/F | Double vision, chemosis, exophthalmos, ataxia/2 months | No | CS | Yes | Normal, non-enhanced | Hyper | NA/NM | NA/NM, NA/NM | No | Midbrain | Dural branches of the bilateral ICAs and ECAs | Sphenoparietal sinus → deep sylvian vein → pontomesencephalic veins | Type IIA+B | Packing of CS with sponges via open surgery | Completely | 1 months | No | 0 | |
| 24 | Li et al. (19) | 73/M | Tetrapraresis, unconsciousness and dyspnea/1 year | Yes (acute cerebral infarction) | TS | Yes | NA/NM, NA/NM | Hyper | Hyper | NA/NM, NA/NM | Yes | Temporal lobe and medulla oblongata extending to the upper thoracic cord | MMA, OA, AphA | Cortical vein, stenotic TS → anterior and posterior spinal vein | Type V | TVE with coiling the TS | Completely | 5 days | No | NA/NM |
| 25 | Pannu et al. (20) | 42/M | Tetrapraresis, bowel and urinary incontinence/1 year | No | Tentorium | No | NA/NM, NA/NM | Hyper | Hyper | NA/NM, NA/NM | Yes | Medulla oblongata extending to the upper cervical cord | MHT of the ICA | Superior petrosal vein → lateral medullary vein → the anterior and posterior spinal veins | Type V | Coagulating DAVF and draining vein | Completely | 12 months | No | 3 |
| 26 | Crum et al. (21) | 35/M | Paraparesis, ataxia, diplopia/several weeks | Yes (uncertain brainstem lesion) | CCJ (jugular foramen) | No | Normal, patchy enhancement | Hyper | Hyper | NA/NM, NA/NM | Yes | Medulla oblongata extending to the upper cervical cord | Branches of the VA and PICA | Spinal medullary veins | Type V | Coagulated and divided the DAVF and draining vein | Completely | 3 months | No | 1 |
| 27 | Oishi et al. (22) | 68/F | Disturbance of brainstem function/NA/NM | NA/NM | TS | NA/NM | NA/NM, NA/NM | Hyper | Hyper | NA/NM, NA/NM | Yes | Medulla oblongata | NA/NM | SPS → spinal PMV | Type V | TVE with coils | Completely | NA/NM | No | NA/NM |
| 28 | Satoh et al. (23) | 38/F | Tetrapraresis, nystagmus, Horner syndrome/NA/NM | No | TS-SS | Yes | Hypo, NA/NM | Hyper | Hyper | NA/NM, NA/NM | No | Medulla oblongata | MMA, OA, AphA, MHT of the ICA, PMA of the VA | SS → spinal PMV | Type V | TVE with coiling the SS | Completely | 1 month | No | 3 |
| 29 | Tanoue et al. (3) | 70/M | Tetrapraresis, sensory disturbance/2 years | No | CCJ (foramen magnum) | No | Normal, non-enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the entire cervical cord | Jugular branch of OA, NMH of AphA | Anterior condylar vein → inferior petrosal sinus → pontomesencephalic vein → anterior spinal vein | Type V | TAE with NBCA via AphA and OA | Incompletely | 14 months | No | 4 or 5 |
| 30 | Akkoc et al. (24) | 45/M | Paraparesis, urinary retention/2 months | Yes (brainstem ischemia or myelitis) | CCJ | No | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the entire cervical cord | OA, NMH of AphA | PMV | Type V | TAE with NBCA via OA | Completely | 3 months | Yes/repeated TAE with NBCA via AphA | 4 or 5 |
| 31 | Iwasaki et al. (25) | 71/F | Decreased abduction of the right eye/5 months | Yes (brain neoplasm) | CS | No | Normal, patchy-enhancement | Hyper | NA/NM | NA/NM, NA/NM | No | Upper pons | MMA, meningeal branch of the ICA | SPS → straight sinus → cerebellar cortical veins → anterior pontomesencephalic vein → PMV | Type V | Stereotactic radiosurgery | Completely | 3 years | No | 0 |
| 32 | Lagares et al. (26) | 65/M | Tetrapraresis, respiratory insufficiency/3 months | Yes (cerebellar infarction) | Torcular | No | NA/NM, NA/NM | Hyper | Hyper | Hypo, hyper | Yes | Medulla oblongata | OA, PMA of the VA | Cerebellar vein → petrosal vein and PMV | Type V | Open surgery | Completely | 6 months | No | 1 |
| 33 | van Rooij et al. (27) | 58/M | Tetrapraresis, bladder retention/3 months | Yes (NA/NM) | Tentorium | No | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the entire cervical cord | MHT of the ICA, MMA, AphA | Petrosal vein → PMV | Type V | TAE with NBCA via MMA | Completely | 1 years | No | 0 |
| 34 | 72/F | Tetrapraresis, paresthesias, bladder retention/2 years | Yes (NA/NM) | CCJ (foramen magnum) | No | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the middle thoracic cord | OA | PMV | Type V | TAE with NBCA via OA | Completely | 2 years | No | 4 or 5 | |
| 35 | Sakamoto et al. (28) | 65/F | Progressive mental and gait disturbance/1 month | No | TS-SS | Yes | Hypo, NA/NM | Hyper | NA/NM | Hetero-geneous, hyper | No | Brainstem and cerebellum | OA, NMH of AphA, posterior branch of MMA, anterior and posterior auricular arteries | NA/NM | TypeIIB | TVE with coils | Completely | NA/NM | No | 0 |
| 36 | Tsutsumi et al. (29) | 62/F | Tetraparesis, occipitalgia and bulbar symptoms/1 year | Yes (intramedullary glioma) | CCJ (foramen magnum) | No | Hypo, rim-like enhancement | Hyper | NA/NM | NA/NM, NA/NM | No | Medulla oblongata extending to the upper thoracic cord | NMH of AphA, meningeal branch of OA | Retrograde drainage to the inferior petrosal sinus → cavernous sinuses | Type IIA | TVE with coils | Completely | Immediately | No | NA/NM |
| 37 | Sugiura et al. (30) | 69/F | Vomiting, ataxia and weakness/2 months | No | SS | Yes | NA/NM, patchy-enhancement | Hyper | NA/NM | Normal, hyper | Yes | Medulla oblongata and hypoer pons | OA | Veins around brainstem → spinal PMV | Type V | TVE with coiling the SS | Completely | 3 weeks | No | 4 or 5 |
| 38 | Wang et al. (31) | 68/M | Focal motor deficit/ NA/NM | NA/NM | CCJ (foramen magnum) | No | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata | NMB of AphA | PMV and anteromedullary cervical veins | Type V | TAE with NBCA via AphA | Completely | 2 years | No | 4 or 5 |
| 39 | Khan et al. (32) | 20/F | Tetrapraresis, urinary retention and respiratory distress/1 month | Yes (demyelinating disease) | Tentorium | No | NA/NM, non-enhanced | Hyper | Hyper | NA/NM, NA/NM | Yes | Pons extending to the upper cervical cord | MHT of the ICA | Cerebellar vein and anterior spinal vein | Type V | Open surgery | Completely | 3 months | No | 3 |
| 40 | Ko et al. (33) | 54/M | Tetrapraresis, hypesthesia, diplopia/5 years | Yes (Tolosa-Hunt syndrome) | CS | No | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the upper cervical cord | MHT of the ICA, MMA | Pontomesencephalic vein → cervical PMV | Type V | TAE with NBCA via multiple feeders | Incompletely | 10 months | Yes/Second-stage embolization and gamma-knife radiosurgery | 4 or 5 |
| 41 | Kleeberg et al. (34) | 60/M | Difficulty to walk/6 weeks | No | Tentorium | No | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the hypoer cervical cord | MHT of the ICA | Cerebellar vein → PMV | Type V | Combined TAE and open surgery | Completely | Immediately | No | 1 or 2 |
| 42 | Patsalides et al. (35) | 53/M | Syncope attacks and tingling of the fingertips/3 months | Yes (NA/NM) | SPS | Yes | NA/NM, enhanced | Hyper | NA/NM | NA/NM, NA/NM | No | Medulla oblongata extending to the upper cervical cord | MHT of the ICA, MMA | Veins around brainstem → spinal veins | Type V | TAE with NBCA via MHT of the ICA | Completely | 6 months | No | 0 |
| 43 | Aixut Lorenzo et al. (36) | 67/F | Neck pain, Tetrapraresis, urinary retention/several days | No | Tentorium (petrosal ridge) | Yes | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the entire cervical cord | MMA, AphA, and OA | Vein around brainstem → spinal PMV | Type V | TAE with Onyx via OA | Completely | 12 months | Yes/TVE | 0 or 1 |
| 44 | Kim et al. (37) | 45/M | Tetrapraresis and respiratory distress/6 months | Yes (demyelinating disease) | Tentorium (petrosal ridge) | No | NA/NM, enhanced | Hyper | Hyper | Normal, NA/NM | No | Medulla oblongata extending to the upper cervical cord | Meningeal branches of bilateral ICAs | Cervical PMV | Type V | Open surgery | Completely | 2 weeks | No | 3 |
| 45 | Peltier et al. (38) | 58/F | Tetrapraresis, urinary retention and breathing difficulty/2 months | No | CCJ | No | NA/NM, enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the upper cervical cord | PMA of the VA | C1 radiculomedullary vein | Type V | Clipping and section of the venous stem | Completely | 6 months | No | 3 |
| 46 | Clark et al. (39) | 49/F | Dysarthric with monotonal hypophonia and ataxia/3 months | No | CS | No | NA/NM, NA/NM | Hyper | Hyper | NA/NM, NA/NM | Yes | Pons extending to the upper cervical cord | MHT of the ICA | NA/NM | NA/NM | TAE to coil the DAVF | Completely | 10 days | No | 2 or 3 |
| 47 | Ogbonnaya et al. (40) | 64/F | Paraparesis, unsteady gait/3 months | No | Tentorium | No | NA/NM, non-enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the upper cervical cord | MMA | PMV | Type V | TAE | Completely | Immediately | No | 4 or 5 |
| 48 | Kulwin et al. (41) | 44/F | Paraparesis, altered mental status, hypopneic/ NA/NM | Yes (brainstem stroke) | SPS | No | NA/NM, enhanced | NA/NM | Hyper | NA/NM, hyper | No | Pons and medulla oblongata | MMA, dural branch of VA | SPS → perimesencephalic vein → PMV | Type V | Surgical disconnection by clipping draining vein | Completely | Immediately | No | 4 or 5 |
| 49 | Clark et al. (42) | 65/F | Tetrapraresis, gastroenteritis, urinary retention/several days | No | SPS | No | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | No | Medulla oblongata and upper cervical spinal cord | MMA, MHT of the ICA | veins around brainstem → PMV | Type V | Combined TAE and surgical obliteration | Completely | Immediately | No | NA/NM |
| 50 | Mathon et al. (43) | 60/F | Progressive ascending myelopathy associated with autonomic dysfunction/NA/NM | No | SPS | No | NA/NM, NA/NM | Hyper | Hyper | NA/NM, NA/NM | Yes | medulla oblongata with cervical spinal cord, | Meningeal arteries of the posterior surface of the internal carotid artery, MMA | Dilated perimedullary veins. | Type V | TAE with glue via MMA | Completely | 1 month | No | 0 |
| 51 | Salamon et al. (44) | 43/M | Paraparesis, urinary retention, vomiting, hiccups/NA/NM | No | CCJ (foramen magnum) | No | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | Yes | Hypoer medulla oblongata extending to the upper cervical cord | Meningeal branch from the VA | Cerebellar veins → venous drainage along the medulla → PMV | Type V | TAE with Onyx | Completely | 3 months | No | 0 |
| 52 | Singh et al. (45) | Middle-aged/M | Paraparesis, urinary retention, vomiting, hiccups/4 months | Yes (periodic paralysis) | Tentorium | No | NA/NM, NA/NM | Hyper | Hyper | NA/NM, NA/NM | Yes | Pons, medulla oblongata extending to the upper cervical cord | MHAs of the ICAs, MMA | Perimesencephalic vein and PMV | Type V | Open surgery | Completely | 3 months | No | 0 |
| 53 | El Asri et al. (46) | 48/M | Tetrapraresis, hypaesthesia, breathing difficulty/10 days | No | Tentorium | No | NA/NM, non-enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Hypoer medulla oblongata extending to the upper cervical cord | MHT of the ICA | Cerebellar veins → PMV | Type V | Open surgery | Completely | 2 years | No | 4 or 5 |
| 54 | Foreman et al. (47) | 59/F | Tetrapraresis, pain, urinary retention/3 weeks | Yes (infarction or contusion) | CCJ | No | NA/NM, non-enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata and entire cervical spinal cord | MHT of the ICA | Pontomesencephalic vein → PMV | Type V | Open surgery | Completely | Immediately | No | 4 or 5 |
| 55 | Gross et al. (48) | 69/M | Progressive hypoer extremity weakness and urinary retention/3 days | Yes (Guillian-Barre syndrome) | Tentorium | No | NA/NM, NA/NM | Hyper | Hyper | NA/NM, NA/NM | Yes | Pons, medulla, and upper cervical spine | MMA, tentorial branch of ICA, dural branches of OA and posterior auricular artery | Cervical spinal veins | Type V | TAE with Onyx | Completely | 10 weeks | No | 3 |
| 56 | 34/F | Progressive extremity weakness/1 week | Yes (transverse myelitis) | TS-SS | No | NA/NM, NA/NM | Hyper | Hyper | NA/NM, NA/NM | Yes | Brainstem and cervicomedullary junction | OA | SPS → petrosal vein and medullary vein → anterior spinal vein and cervicomedullary vein | Type V | TAE with Onyx | Completely | 3 months | No | 0 | |
| 57 | Wu et al. (49) | 46/F | Paraparesis, vertigo, vomiting and dysphagia/1 month | Yes (brainstem infarction) | CCJ | No | NA/NM, partial enhancement | Hyper | Hyper | NA/NM, NA/NM | Yes | Pons, medulla oblongata. | Meningeal branch from the radicular artery of the VA | Pontomesencephalic veins → basal vein and anterior spinal vein | Type V | TAE with Onyx | Completely | 6 months | No | 0 |
| 58 | Haryu et al. (50) | 62/M | Upper limb weakness and difficulty in walking/4 months | NA/NM | Tentorium (petrosal ridge) | NA/NM | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | Yes | Cervical spinal cord and medulla oblongata | MMA | Petrosal vein into the anterior spinal veins | Type V | Open surgery | Completely | 18 months | No | 2 |
| 59 | 64/M | Myelopathy, bulbar palsy/NA/NM | Yes (NA/NM) | NA/NM | NA/NM | NA/NM, heterogeneously enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Cervical spinal cord and medulla oblongata | NA/NM | Spinal veins | Type V | NA/NM | NA/NM | NA/NM | NA/NM | 3 | |
| 60 | 68/M | Myelopathy, respiratory failure/NA/NM | NA/NM | NA/NM | NA/NM | NA/NM, non-enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Cervical spinal cord and medulla oblongata | AphA | Anterior spinal veins | Type V | Open surgery | NA/NM | NA/NM | NA/NM | 4 | |
| 61 | Roelz et al. (51) | 76/M | Nausea and vomiting, inability to walk, and blurred vision/8 months | Yes (brainstem glioma or lymphoma) | CCJ (Posterior jugular foramen) | No | NA/NM, enhanced | Hyper | Hyper | NA/NM, NA/NM | Yes | Pontomedullary junction extending to inferior cerebellar peduncle | MMA, AphA, PAA, and OA | Lateral medullary into the anterior perimedullary/perispinal veins | Type V | TAE with Onyx via MMA, AphA, PAA | Completely | 10 months | Yes/combined endovascular (via OA) and surgical approach | 2 |
| 62 | Le et al. (52) | 36/M | Headache, hypoesthesia, vomiting, ataxia/2 months | Yes (brainstem glioma) | Tentorium (petrosal apex) | No | Normal, punctiform enhancement | Hyper | Hyper | NA/NM, NA/NM | Yes | Medulla oblongata | MMAs, AphA, internal maxillary artery | Spinal PMV | Type V | TAE with NBCA | Completely | 1 year | No | 0 |
| 63 | Alvare et al. (53) | 69/M | Nausea, vomiting, paraparesis/NA/NM | Yes (encephalitis) | Tentorium (petrosal ridge) | No | NA/NM, enhanced | Hyper | Hyper | Normal, hyper | No | Pons and medulla oblongata | MMA, anterior inferior cerebellar artery | Veins of the cerebello-pontine angle → veins around the brainstem → spinal PMV | Type V | Combined TAE and clip and coagulate the draining vein | Completely | 3 months | No | 0 |
| 64 | Pop et al. (54) | 38/M | Seizure, tetraplegia, respiratory difficulty/1 month | Yes (Guillain-Barre syndrome) | CCJ (foramen magnum) | No | Low, non-enhanced | Hyper | Hyper | NA/NM, NA/NM | Yes | Medulla oblongata extending to the entire cervical cord | OA, AphA | Bidirectional drainage to cortical temporal vein and spinal veins | Type V | TAE with Onyx via OA | Completely | 6 months | No | 3 |
| 65 | Abud et al. (55) | 66/F | Tetraparesis/1 month | No | SS | No | NA/NM, non-enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the upper cervical cord | OA | Cerebellar cortical venous drainage → PMV | Type V | TAE with Onyx via OA | Completely | 3 months | No | 0 |
| 66 | Abdelsadg et al. (56) | 65/F | Tetraparesis, dizziness, urination difficulty/several days | No | CCJ | Yes | NA/NM, NA/NM | Hyper | Hyper | NA/NM, Hyper | No | Medulla oblongata extending to the upper cervical cord | MHT of the ICA, MMA, | SPS → brainstem and cervical PMV | Type V | TAE | Completely | 3 months | No | 3 |
| 67 | Enokizono et al. (57) | 50s/F | Tetraparesis, numbness of limbs, urination difficulty/1 month | No | CCJ | No | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the upper thoracic cord | Meningeal branch from the radicular artery of the VA | Anterior and posterior spinal veins | Type V | Open surgery | Completely | NA/NM | No | NA/NM |
| 68 | 60s/M | Tetraparesis, numbness of limbs, urination difficulty/7 months | No | Tentorium | No | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the upper thoracic cord | MHT of the ICA, MMA, accessory meningeal artery | Petrosal vein → veins around the brainstem → PMV | Type V | Open surgery | Completely | NA/NM | No | NA/NM | |
| 69 | 60s/M | Tetraparesis, numbness of limbs, respiratory difficulty/2 months | No | Tentorium | No | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the entire cervical cord | MMA | Petrosal vein → veins around the brainstem → PMV | Type V | Combined TAE and clip the draining vein | Completely | NA/NM | No | NA/NM | |
| 70 | Tanaka et al. (58) | 64/M | Paraparesis, bladder dysfunction/NA/NM | No | Occipital sinus | Yes | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | No | Medulla oblongata extending to the upper cervical cord | PMAs of the VAs | Occipital sinus → anterior spinal vein | Type V | TAE with Onyx via PMAs of the VAs | Completely | 8 months | No | 2 |
| 71 | Emmer et al. (59) | 65/M | Eye movement abnormalities, limb weakness, and gait instability/2 years | Yes (tumor) | CCJ | No | NA/NM, heterogeneously enhanced | Hyper | Hyper | NA/NM, NA/NM | Yes | Medulla oblongata and cerebellum | PMA of the VA | Cerebellar vein | Type III | TAE with NBCA via PMA | Completely | Immediately | No | 4 or 5 |
| 72 | Duan et al. (60) | 67/F | Paraparesis, headache and progressive Confusion/1 month | Yes (brainstem tumor) | SPS | No | NA/NM, partially enhanced | Hyper | Hyper | Hyper, NA/NM | No | Cerebellum and pons | MMA, OA | SPS → PMV | Type V | TAE | Completely | Immediately | No | 4 or 5 |
| 73 | Chen et al. (61) | 25/F | Paresthesias and paralysis of hypoer extremity, dyspnea/several days | Yes (encephalitis and myelitis) | Posterior fossa | No | NA/NM, enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Pons to C2/C3 | Posterior meningeal branch of VA | Anterior spinal vein | Type V | TAE | Completely | NA/NM | No | NA/NM |
| 74 | Bernard et al. (62) | 65/M | Progressive ataxia, swalhypoing dnormalrders, and bilateral tinnitus/5 months | Yes (glioma) | CCJ | No | NA/NM, enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla and hyper cervical cord | Branches of AphA | Cerebellar medullary vein (white arrowhead) reaching perimedullary veins | Type V | Open surgery | Completely | 1 month | No | 0 |
| 75 | Zhang et al. (4) | 33/M | Progressive weakness of the hypoer extremities and gait disturbance/2 months | Yes (transverse myelitis) | Tentorium | No | NA/NM, patchy enhancement | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata and cervical spinal cord | MHT of ICA | Perimedullary veins | Type V | TAE with Onyx | Completely | 1 month | No | 2 |
| 76 | Li et al. (63) | 54/F | Limb weakness and sphincter dysfunction/20 days | No | Tentorium (petrosal apex) | No | NA/NM, non- enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata and cervical spinal cord | MHT of ICA | Medullary into the perimedullary | Type V | Open surgery | Completely | 1 month | No | 1 |
| 77 | Wang et al. (64) | 53/M | Numbness of the limbs, gait disturbance and cough/NA/NM | No | CCJ | No | NA/NM, patchy enhancement | Hyper | Hyper | Hyper, NA/NM | Yes | Pons to medulla oblongata | OA of the VA | SS and cortical venous drainage | Type IIB | TAE with Onyx via OA | Completely | Immediately | No | 3 |
| 78 | 53/M | Tetrapraresis, hypaesthesia, swalhypoing difficulty/2 months | No | CCJ | No | Low, non- enhanced | Hyper | Hyper | Normal, NA/NM | Yes | Medulla oblongata | Dural branch of VA | Posterior spinal veins | Type V | Coagulating and cutting draining veins | Completely | Immediately | No | 4 or 5 | |
| 79 | Takahashi et al. (65) | 63/M | Tetraparesis, respiratory failure/5 months | No | CCJ | No | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata | OA, AphA | Anterior spinal vein | Type V | TAE | Completely | 2 months | No | 3 |
| 80 | Copelan et al. (66) | 59/M | Dizziness, nausea, and vomiting, vertigo/5 weeks | No | SPS | No | NA/NM, mild patchy enhancement | Hyper | Hyper | Mild hyper, hyper | Yes | Medulla oblongata extending to the upper cervical cord | MMA, OA, AphA | Petrosal vein → PMV | Type V | Combination of endovascular embolization and surgical resection | Completely | 3 years | No | 1 or 2 |
| 81 | 72/M | Slurred speech, and dysphagia/3 months | No | CCJ (anterior condylar vein) | No | NA/NM, enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata and cerebellar flocculus | AphA | Anterior condylar vein, petrosal vein and PMV | Type V | TAE with Onyx via AphA | Completely | 5 months | No | 1 or 2 | |
| 82 | 35/F | Progressive unsteady gait and paraparesis/1 month | No | SPS | No | NA/NM, mildly enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata | OA | SPS → PMV | Type V | TAE with Onyx | Completely | 3months | No | 2 | |
| 83 | 64/M | Tetraparesis/6 months | Yes (transverse myelitis) | SPS | No | NA/NM, enhanced | Hyper | NA/NM | NA/NM, NA/NM | Yes | Medulla oblongata extending to the upper cervical cord | MHT of ICA, OA | PMV | Type V | TAE and surgical resection | Completely | 12 months | No | 4 or 5 | |
| 84 | Rodriguez et al. (67) | 68/M | Progressive hypoer extremity weakness/NA/NM | No | Tentorium | No | NA/NM, NA/NM | NA/NM | NA/NM | NA/NM, NA/NM | No | Cervicomedullary junction to C7 | PMA | Doral and ventral perimedullary veins | Type V | TAE with 50% ethanol | Incompletely | NA/NM | Yes/open surgery | 3 |
| 85 | Shimizu et al. (68) | 75/M | Paraparesis, hypaesthesia, urinary retention/6 months | No | Anterior cranial fossa | Yes | NA/NM, NA/NM | Hyper | NA/NM | NA/NM, NA/NM | Yes | Cerebellum and hypoer pons extending to the upper cervical cord | Anterior ethmoidal artery | Olfactory vein → basal vein of Rosenthal → veins around the brainstem → PMV | Type V | Open surgery | Completely | 2 months | No | 4 or 5 |
| 86 | Chen et al. (69) | 66/M | Dizziness, truncal ataxia, impaired gait/1 month | Yes (NA/NM) | CCJ | No | NA/NM, partially enhanced | Hyper | NA/NM | Normal, hyper | Yes | Hypoer pons and medulla oblongata | OA, meningeal branch of VA | PMV, reflux into veins around the brainstem | Type V | TAE with Onyx | Completely | 3 months | No | 1 or 2 |
CCJ, cranio-cervical junction; CS, cavernous sinus; DAVF, dural arteriovenous fistula; ECA, external carotid artery; F, female; ICA, internal carotid artery; M, male; MHT, meningohypophysal trunk; MMA, middle meningeal; AphA, ascending pharyngeal artery; VA, vertebral artery; MRI, magnetic resonance imaging; mRS, modified Rankin scale; NA/NM, not applicable/not mentioned; NBCA, N-butyl-2-cyanoacrylate; NMB, neuromeningeal branch; OA, occipital artery; PAA, posterior auricular artery; PMA, posterior meningeal artery; PMV, perimedullary vein; PVA, polyvinyl alcohol; SPS, superior petrosal sinus; SS, sigmoid sinus; TAE, transarterial embolization; TS, transverse sinus; TVE, transvenous embolization; VA, vertebral artery.