A Novel Weave Tether Technique for Proximal Junctional Kyphosis Prevention in 71 Adult Spinal Deformity Patients: A Preliminary Case Series Assessing Early Complications and Efficacy.

BACKGROUND: Proximal junctional kyphosis (PJK) rates may be as high as 69.4% after adult spinal deformity (ASD) surgery. PJK is one of the greatest unsolved challenges in long-segment fusions for ASD and remains a common indication for costly and impactful revision surgery. Junctional tethers may help to reduce the occurrence of PJK by attenuating adjacent-segment stress. OBJECTIVE: To report our experience and assess early safety associated with a novel "weave-tether technique" (WTT) for PJK prophylaxis in a large series of patients. METHODS: This single-center retrospective study evaluated consecutive patients who underwent ASD surgery including WTT between 2017 and 2018. Patient demographics, operative details, standard radiographic measurements, and complications were analyzed. RESULTS: A total of 71 patients (mean age 66 ± 12 yr, 65% women) were identified. WTT included application to the upper-most instrumented vertebrae (UIV) + 1 and UIV + 2 in 38(53.5%) and 33(46.5%) patients, respectively. No complications directly attributed to WTT usage were identified. For patients with radiographic follow-up (96%; mean duration 14 ± 12 mo), PJK occurred in 15% (mean 1.8 ± 1.0 mo postoperatively). Proximal junctional angle increased an average 4° (10° to 14°, P = .004). Rates of symptomatic PJK and revision for PJK were 8.8% and 2.9%, respectively. CONCLUSION: Preliminary results support the safety of the WTT for PJK prophylaxis. Approximately 15% of patients developed radiographic PJK, no complications were directly attributed to WTT usage, and the revision rate for PJK was low. These early results warrant future research to assess longer-term efficacy of the WTT for PJK prophylaxis in ASD surgery.

Contribution of Neural Elements to Thoracic Stability.

AIM: Studies of spinal biomechanics typically do not focus on the contributions to range of motion (ROM) of the primary components of the spinal canal, dura, arachnoid, pia, spinal cord, nerve roots, ligaments, and vessels. We sought to determine the stability offered by these soft tissues in vitro. MATERIAL AND METHODS: Human cadaveric segments were tested intact, after osteoligamentous destabilization, and after transection of T8-9 spinal canal components. Specimens were induced into flexion, extension, axial rotation, and lateral bending using non-constraining, non-destructive pure moment while tracking motion response stereophotogrammetrically. The range of motion (ROM) was compared in each condition after adjusting for soft tissue creep. RESULTS: After spinal canal element transection, ROM increased in all directions (mean 4.7%). This increase was most pronounced during lateral bending (p=0.055). The cumulative ROM from all directions of loading showed a statistically significant mean increase of 3.3% (p=0.040). CONCLUSION: Sectioning of canal elements was found to cause a measurable increase in ROM. Although nonviable tissues were tested, living tissues are also likely to contribute to spinal stability.

Biomechanics of dynamic rod segments for achieving transitional stiffness with lumbosacral fusion.

BACKGROUND: Transitioning from rigid to flexible hardware at the distal rostral or caudal lumbar or lumbosacral level hypothetically maintains motion at the transition level and protects the transition level and intact adjacent levels from stresses caused by fusion. OBJECTIVE: To biomechanically compare transitional and rigid constructs with uninstrumented specimens in vitro. METHODS: Human cadaveric L2-S1 segments were tested (1) intact, (2) after L5-S1 rigid pedicle screw-rod fixation, (3) after L4-S1 rigid pedicle screw-rod fixation, and (4) after hybrid fixation rigidly spanning L5-S1 and dynamically spanning L4-L5. Pure moments (maximum 7.5 Nm) induced flexion, extension, lateral bending, and axial rotation while motion was recorded optoelectronically. Additionally, specimens were studied in flexion/extension with a 400-N compressive follower load. Strain gauges on laminae were used to extract facet loads. RESULTS: The range of motion at the transition segment (L4-L5) for the hybrid construct was significantly less than for the intact condition and significantly greater than for the rigid 2-level construct during lateral bending and axial rotation but not during flexion or extension. Sagittal axis of rotation at L4-L5 shifted significantly after rigid 2-level or hybrid fixation (P < .003) but shifted significantly farther posterior and rostral with rigid fixation (P < .02). Instrumentation altered L4-L5 facet load at more than the L3-L4 facet load. CONCLUSION: The effect of the dynamic rod segment on the kinematics of the transition level was less pronounced than that of a fully rigid construct in vitro with this particular rod system. This experimental model detected no biomechanical alterations at adjacent intact levels with hybrid or rigid systems.

Characteristics of immediate and fatigue strength of a dual-threaded pedicle screw in cadaveric spines.

BACKGROUND CONTEXT: Novel dual-threaded screws are configured with overlapping (doubled) threads only in the proximal shaft to improve proximal cortical fixation. PURPOSE: Tests were run to determine whether dual-threaded pedicle screws improve pullout resistance and increase fatigue endurance compared with standard pedicle screws. STUDY DESIGN/SETTING: In vitro strength and fatigue tests were performed in human cadaveric vertebrae and in polyurethane foam test blocks. PATIENT SAMPLE: Seventeen cadaveric lumbar vertebrae (14 pedicles) and 40 test sites in foam blocks were tested. OUTCOME MEASURES: Measures for comparison between standard and dual-threaded screws were bone mineral density (BMD), screw insertion torque, ultimate pullout force, peak load at cyclic failure, and pedicular side of first cyclic failure. METHODS: For each vertebral sample, dual-threaded screws were inserted in one pedicle and single-threaded screws were inserted in the opposite pedicle while recording insertion torque. In seven vertebrae, axial pullout tests were performed. In 10 vertebrae, orthogonal loads were cycled at increasing peak values until toggle exceeded threshold for failure. Insertion torque and pullout force were also recorded for screws placed in foam blocks representing healthy or osteoporotic bone porosity. RESULTS: In bone, screw insertion torque was 183% greater with dual-threaded than with standard screws (p<.001). Standard screws pulled out at 93% of the force required to pull out dual-threaded screws (p=.42). Of 10 screws, five reached toggle failure first on the standard screw side, two screws failed first on the dual-threaded side, and three screws failed on both sides during the same round of cycling. In the high-porosity foam, screw insertion torque was 60% greater with the dual-threaded screw than with the standard screw (p=.005), but 14% less with the low-porosity foam (p=.07). Pullout force was 19% less with the dual-threaded screw than with the standard screw in the high-porosity foam (p=.115), but 6% greater with the dual-threaded screw in the low-porosity foam (p=.156). CONCLUSIONS: Although dual-threaded screws required higher insertion torque than standard screws in bone and low density foam, dual-threaded and standard pedicle screws exhibited equivalent axial pullout and cyclic fatigue endurance. Unlike single-threaded screws, the mechanical performance of dual-threaded screws in bone was relatively independent of BMD. In foam, the mechanical performance of both types of screws was highly dependent on porosity.

Biomechanical contribution of the rib cage to thoracic stability.

STUDY DESIGN: In vitro assessment of rib cage biomechanics in the region of true ribs with the ribs intact then sequentially resected in 5 steps. OBJECTIVE: To determine the contribution of the rib cage to thoracic spine stability and kinematics. SUMMARY OF BACKGROUND DATA: Previous in vitro studies of rib cage biomechanics have used animal spines or human cadaveric spines with ribs left unsecured, limiting the ability of the ribs to contribute to stability. METHODS: Eight upper thoracic specimens that included 4 ribs and sternum were tested in special fixtures that disallowed relative movement of the distal ribs and their vertebrae. While applying 7.5 Nm pure moments in 3 planes, angular motion at the middle motion segment was studied in intact specimens and then (1) after splitting the sternum, (2) after removing the sternum, (3) after removing 50% of ribs, (4) after removing 75% of ribs, and (5) after disarticulating and completely removing ribs. RESULTS: During flexion/extension, the sternum and anterior rib cage most contributed to stability. During lateral bending, the posterior rib cage most contributed to stability. During axial rotation, stability was directly related to the proportion of ribs remaining intact. On average, intact ribs accounted for 78% of thoracic stability. An intact rib cage shifted the axis of rotation unpredictably, but its position remained consistent after partial resection of the ribs. During lateral bending, coupled axial rotation was mild and unaffected by ribs. CONCLUSION: Because of testing methodology, the rib cage accounted for a greater percentage of thoracic stability than previously estimated. Different rib cage structures resisted motion in different loading planes.

Analysis of in vivo kinematics of 3 different cervical devices: Bryan disc, ProDisc-C, and Prestige LP disc.

OBJECT: Cervical arthroplasty has emerged as a means of preventing adjacent segment disease by preserving motion, restoring sagittal balance, and mimicking natural spinal kinematics. The purpose of this retrospective in vivo study was to characterize the impact of arthroplasty on sagittal balance and segmental kinematics of the cervical spine. METHODS: Sixty patients receiving the Bryan disc, ProDisc-C, or Prestige LP disc were retrospectively analyzed. Only single-level arthroplasty cases were included in this study. Lateral dynamic radiographs of the cervical spine were evaluated using quantitative measurement analysis software to determine the kinematics at the index level both preoperatively and 1 year postoperatively. Collected parameters included range of motion (ROM), disc angles, shell angles, anterior and posterior disc heights (ADHs/PDHs), translation, and center of rotation (COR). Preoperative and postoperative data were compared using the Student t-test, with p < 0.05 indicating significance. RESULTS: The Bryan and Prestige LP discs preserved motion, whereas the ProDisc-C increased segmental ROM from extension to flexion. Following surgery, the Bryan disc exhibited significant shell angle kyphosis, while ProDisc-C and Prestige LP retained lordosis. Both ADHs and PDHs decreased following insertion of the Bryan disc. In contrast, the ProDisc-C increased the ADHs and PDHs by 80% and 52%, respectively, and the Prestige LP disc increased the ADHs and PDHs by 20%. Only the ProDisc-C demonstrated significant translation of 0.7 mm. The ProDisc-C shifted the COR x by 0.9 mm anteriorly, while the Prestige LP disc demonstrated a significant superior shift of 2.2 mm in COR y. CONCLUSIONS: All discs adequately maintained ROM at the surgical level. The greatest difference among the 3 devices was in the disc height and index angle measurements.

Biomechanics of thoracic short versus long fixation after 3-column injury.

OBJECT: Posterior screw-rod fixation for thoracic spine trauma usually involves fusion across long segments. Biomechanical data on screw-based short-segment fixation for thoracic fusion are lacking. The authors compared the effects of spanning short and long segments in the thoracic spine. METHODS: Seven human spine segments (5 segments from T-2 to T-8; 2 segments from T-3 to T-9) were prepared. Pure-moment loading of 6 Nm was applied to induce flexion, extension, lateral bending, and axial rotation while 3D motion was measured optoelectronically. Normal specimens were tested, and then a wedge fracture was created on the middle vertebra after cutting the posterior ligaments. Five conditions of instrumentation were tested, as follows: Step A, 4-level fixation plus cross-link; Step B, 2-level fixation; Step C, 2-level fixation plus cross-link; Step D, 2-level fixation plus screws at fracture site (index); and Step E, 2-level fixation plus index screws plus cross-link. RESULTS: Long-segment fixation restricted 2-level range of motion (ROM) during extension and lateral bending significantly better than the most rigid short-segment construct. Adding index screws in short-segment constructs significantly reduced ROM during flexion, lateral bending, and axial rotation (p < 0.03). A cross-link reduced axial rotation ROM (p = 0.001), not affecting other loading directions (p > 0.4). CONCLUSIONS: Thoracic short-segment fixation provides significantly less stability than long-segment fixation for the injury studied. Adding a cross-link to short fixation improved stability only during axial rotation. Adding a screw at the fracture site improved short-segment stability by an average of 25%.

Stabilization of the atlantoaxial joint with C1-C3 lateral mass screw constructs: biomechanical comparison with standard technique.

BACKGROUND: Anatomically and biomechanically, the atlantoaxial joint is unique compared with the remainder of the cervical spine. OBJECTIVE: To assess the in vitro stability provided by 2 C2 screw sparing techniques in a destabilized model of the atlantoaxial joint and compare with the gold standard system. METHODS: The 3-dimensional intervertebral motion of 7 human cadaveric cervical spine specimens was recorded stereophotogrammetrically while applying nonconstraining, nondestructive pure moments during flexion-extension, left and right axial rotation, and left and right lateral bending. Each specimen was tested in the intact state, followed by destabilization (odontoidectomy) and fixation as follows: (1) C1 and C3 lateral mass screws rods with sublaminar wiring of C2 (LC1-C3 + SW), (2) C1 and C3 lateral mass screws rods with a cross-link in the C1-2 interlaminar space (LC1-C3 + CL), (3) C1 and C3 lateral mass screw rods alone (negative control), and (4) C1 lateral mass and C2 pedicle screws rods augmented with C1-2 interspinous wire and graft (LC1-PC2, control group). RESULTS: Compared with the intact spine, each instrumented state significantly stabilized range of motion and lax zone at C1-2 (P < .001, 1-way repeated-measures analysis of variance). LC1-C3 + SW was equivalent to LC1-PC2 during flexion and lateral bending and superior to LC1-C3 + CL during lateral bending, while LC1-C3 + CL was equivalent to LC1-PC2 only during flexion. In all other comparisons, LC1-PC2 was superior to both techniques. CONCLUSION: From a biomechanical perspective, both C2 screw sparing techniques provided sufficient stability to be regarded as an alternative for C1-2 fixation. However, because normal motion across C2-3 is sacrificed, these constructs should be used in patients with unfavorable anatomy for standard fixations.

Biomechanical evaluation of posterior thoracic transpedicular discectomy.

OBJECT: The authors investigated the biomechanical properties of transpedicular discectomy in the thoracic spine and compared the effects on spinal stability of a partial and total facetectomy. METHODS: Human thoracic specimens were tested while intact, after a transpedicular discectomy with partial facetectomy, and after an additional total facetectomy was incorporated. Nonconstraining pure moments were applied under load control (maximum 7.5 Nm) to induce flexion, extension, lateral bending, and axial rotation while spinal motion was measured at T8-9 optoelectronically. The range of motion (ROM) and lax zone were determined in each specimen and compared among conditions. RESULTS: Transpedicular discectomy with and without a total facetectomy significantly increased the ROM and lax zone in all directions of loading compared with the intact spine (p < 0.008). The segmental increase in ROM observed with the transpedicular discectomy was 25%. The additional total facetectomy created an insignificant 3% further increase in ROM compared with medial facetectomy (p > 0.2). CONCLUSIONS: Transpedicular discectomy can be performed in the thoracic spine with a modest decrease in stability expected. Because the biomechanical behavior of a total facetectomy is equivalent to that of a medial facetectomy, the additional facet removal may be incorporated without further biomechanical consequences.

Effect of arthroplasty design on cervical spine kinematics: analysis of the Bryan Disc, ProDisc-C, and Synergy disc.

OBJECT: Cervical total disc replacement has emerged as a surgical option to preserve motion and potentially avoid adjacent-segment disease after anterior cervical discectomy and fusion. Recently, much attention has been directed at the ability of a given device to maintain and/or restore normal segmental alignment. Nonphysiological disc and segmental angulation could result in increased stresses transmitted to the facet joints and posterior elements, conflicting with the essence of arthroplasty and potentially leading to adjacent-segment disease. The goal of this study was to contrast device alignment and segmental kinematics provided by 3 different cervical disc prostheses. METHODS: Sixty patients were retrospectively analyzed and divided into 3 groups receiving the Bryan, ProDisc-C, or Synergy disc. Only single-level arthroplasty cases were included in the study. Lateral dynamic radiographs of the cervical spine were analyzed using quantitative motion analysis software (Medical Metrics, Inc.) to analyze the kinematics at the index level both preoperatively and postoperatively. Several parameters were noted, including range of motion, disc angles, shell angles, anterior and posterior disc heights, translation, and center of rotation. Preoperative and postoperative data were compared using the Student t-test with a significance level of p < 0.05. RESULTS: Postoperatively, all 3 disc groups maintained adequate range of motion at the implanted level. With respect to the shell angles, the Synergy disc demonstrated the least variability, maintaining 6 degrees lordotic configuration between the device endplates. In the Bryan disc group, significant shell kyphosis developed postoperatively (p < 0.0001). Both ProDisc-C and Synergy discs significantly increased anterior and posterior disc heights (p < 0.0001). The Bryan and Synergy discs maintained the natural center of rotation, whereas significant anterior shift occurred with ProDisc-C. CONCLUSIONS: The goal for motion preservation at the implanted level was achieved using all 3 devices. The Synergy disc was unique in its ability to alter device angulation by 6 degrees. The Bryan disc demonstrated device endplate kyphosis. Both the Synergy disc and ProDisc-C increased disc space height.

Quantitative analysis of misplaced pedicle screws in the thoracic spine: how much pullout strength is lost?: presented at the 2009 Joint Spine Section Meeting.

OBJECT: The object of this study was to investigate the effects of iatrogenic pedicle perforations from screw misplacement on the mean pullout strength of thoracic pedicle screws. METHODS: Forty human thoracic vertebrae (T6-11) from human cadavers were studied. Before pedicle screws were inserted, the specimens were separated into 4 groups according to the type of screw used: 1) standard pedicle screw (no cortical perforation); 2) screw with medial cortical perforation; 3) screw with lateral cortical perforation; and 4) "airball" screw (a screw that completely missed the vertebral body). Consistency among the groups for bone mineral density, pedicle diameter, and screw insertion depth was evaluated. Finally, each screw was pulled out at a constant displacement rate of 10 mm/minute while ultimate strength was recorded. RESULTS: Compared with well-placed pedicle screws, medially misplaced screws had 8% greater mean pullout strength (p = 0.482) and laterally misplaced screws had 21% less mean pullout strength (p = 0.059). The difference in mean pullout strength between screws with medial and lateral cortical perforations was significant (p = 0.013). Airball screws had only 66% of the mean pullout strength of well-placed screws (p = 0.009) and had 16% lower mean pullout strength than laterally misplaced screws (p = 0.395). CONCLUSIONS: This in vitro study showed a significant difference in mean pullout strength between medial and lateral misplaced pedicle screws. Moreover, airball screws were associated with a significant loss of pullout strength.

Biomechanics of a novel minimally invasive lumbar interspinous spacer: effects on kinematics, facet loads, and foramen height.

OBJECTIVE: To study the alteration to normal biomechanics after insertion of a lumbar interspinous spacer (ISS) in vitro by nondestructive cadaveric flexibility testing. METHODS: Seven human cadaveric specimens were studied before and after ISS placement at L1-L2. Angular range of motion, lax zone, stiff zone, sagittal instantaneous axis of rotation (IAR), foraminal height, and facet loads were compared between conditions. Flexion, extension, lateral bending, and axial rotation were induced using pure moments (7.5 Nm maximum) while recording motion optoelectronically. The IAR was measured during loading with a 400 N compressive follower. Foraminal height changes were calculated using rigid body methods. Facet loads were assessed from surface strain and neural network analysis. RESULTS: After ISS insertion, range of motion and stiff zone during extension were significantly reduced (P < .01). Foraminal height was significantly reduced from flexion to extension in both normal and ISS-implanted conditions; there was significantly less reduction in foraminal height during extension with the ISS in place. The ISS reduced the mean facet load by 30% during flexion (P < .02) and 69% during extension (P < .015). The IAR after ISS implantation was less than 1 mm from the normal position (P > .18). CONCLUSION: The primary biomechanical effect of the ISS was reduced extension with associated reduced facet loads and smaller decrease in foraminal height. The ISS had little effect on sagittal IAR or on motion or facet loads in other directions.

Biomechanical comparison of costotransverse process screw fixation and pedicle screw fixation of the upper thoracic spine.

OBJECTIVE: To compare the biomechanics of costotransverse process screw fixation with those of pedicle screw fixation in a cadaveric model of the upper thoracic spine. METHODS: Ten human thoracic spines were instrumented across the T3-T4 segment with costotransverse and pedicle screws. Nonconstraining pure moments (maximum, 6.0 Nm) were applied to induce flexion, extension, lateral bending, and axial rotation. The range of motion, lax zone, and stiff zone were determined in each specimen in the normal state, after 3-column destabilization, and after instrumentation. After flexibility testing was completed, axial screw pull-out strength was assessed. RESULTS: In all directions of loading, both fixation techniques significantly decreased lax zone and range of motion at T3-T4 compared with the destabilized state (P < .001). During all loading modes except lateral bending, pedicle screw fixation allowed significantly less range of motion than costotransverse screw fixation. Pedicle screws provided 62% greater resistance to axial pull-out than costotransverse screws. CONCLUSION: The costotransverse screw technique seems to provide only moderately stiff fixation of the destabilized thoracic spine. Pedicle screw fixation seems to have more favorable biomechanical properties. These data suggest that the costotransverse process construct is better used as a salvage procedure rather than as a primary fixation strategy.

Tectal plate tumors.

Tectal plate is a rare location for a tumor. Many papers have described different types of pathology arising in that location including tumors, vascular lesions, inflammatory and infectious processes. In this paper we describe our experience in treating seven patients with tectal plate lesions, with different ages and types of pathology: five patients presented with low grade gliomas, one with lung cancer metastasis and the last presenting with a tectal plate cavernoma. Open surgery was performed in three cases (due to tumor enlargement or need for the exact diagnosis). In the other cases, the treatment of non-communicating hydrocephalus was the only treatment employed. The prognosis is of course dependent on the underlining pathology. In our series, except in the metastatic tumor case and the cavernoma, the other types of lesion consisted of low grade gliomas. These lesions represent a different type of brain stem tumor sharing a common good prognosis, with a benign behavior. We believe that tectal tumors must be managed case by case. When a patient presents with a benign lesions in the tectal region, treating the main symptom--hydrocephalus--should be the first attempt in management of these lesions.

Tectal plate tumors

Tumores na região do teto mesencefálico são raros. Vários tipos de lesões como tumores, lesões vasculares, inflamatórias e infecciosas localizam-se nesta região. Nós revimos o tratamento adotado em sete pacientes com diferentes tipos de lesões tectais: cinco pacientes apresentando gliomas de baixo grau, um paciente com lesão metastática proveniente de câncer de pulmão e um com cavernoma. O tratamento cirúrgico com abordagem direta da lesão foi realizado em três casos (devido ao aumento do volume tumoral ou quando houve necessidade da confirmação diagnóstica). Nos demais casos o tratamento para a hidrocefalia não-comunicante foi o método empregado. O prognóstico dessas lesões é baseado no tipo de patologia em questão. Em nossa série, com exceção do caso de metástase e do paciente com cavernoma, as demais lesões foram gliomas de baixo grau. Estas lesões representam um subgrupo diferenciado de tumores de tronco encefálico, apresentando bom prognóstico e tendo comportamento benigno com sobrevida elevada. Acreditamos que tumores da região tectal devam ser avaliados caso a caso. Na hipótese diagnóstica de uma lesão benigna, o tratamento do principal complexo sindrômico – hidrocefalia não-comunicante – é provavelmente a melhor conduta a ser empregada.

Surgical management of cerebrospinal fluid rhinorrhea under endoscopic control.

The surgical management of cerebrospinal fluid (CSF) rhinorrhea has changed after the introduction of functional endoscopic sinus surgery.The following three cases illustrate the repair of CSF leaks with the use of rigid endoscope. Two patients had the diagnosis and the site confirmed after intrathecal fluoresceine saline injection. The obliteration of the CSF was achieved with fat free, mucoperichondrial or mucoperiostal free grafts taken from middle or inferior turbinate and kept in place by fibrin glue. Primary closure was achieved in all patients. The repair of the CSF rhinorrhea by endonasal endoscopic surgery is safe, effective and is a valid alternative to the cranial approach.

Remote hemorrhage from the site of craniotomy.

Postoperative intracranial hemorrhage is a serious and sometimes a fatal neurosurgical complication. Hemorrhage occurring at regions remote from the site of intracranial operations comprises an uncommon affection, most ignored by the assistant physicians. It bares a still incomprehensive pathophysiology, despite several theories trying to explain it. Looks like a common sense that the presence of the remote site hemorrhage cannot be related to concomitant presence of hypertension, coagulopathy or undiscovered lesions. We report three cases of postoperative hemorrhages occurring in a remote site of supratentorial craniotomies, two patients presented cavernous sinus meningeoma and one patient was submitted to intracranial vascular surgery.

Surgical management of cerebrospinal fluid rhinorrhea under endoscopic control

Descrevemos a técnica de oclusão endoscópica por via endonasal de fístula liquórica proveniente do andar anterior em três pacientes. Dois pacientes tiveram o diagnóstico e os orifícios da fístula localizados após injeção intratecal de fluoresceína sódica. A oclusão foi obtida com enxerto de gordura livre, fragmentos de mucopericôndrio septal ou mucoperiósteal retirado do corneto médio ou inferior e selados com o auxílio de cola de fibrina. A cirurgia endoscópica endonasal é técnica segura e eficaz no tratamento da fístula esfeno-etmoidal, constituindo alternativa à abordagem craniana.

Remote hemorrhage from the site of craniotomy

Hemorragia intracraniana de ocorrência em pós-operatório é grave complicação das cirurgias intracranianas. O aparecimento de foco hemorrágico em regiões distantes ao sítio operatório original é considerado incomum, e muitas vezes ignorado pelos médicos assistentes. A fisiopatologia envolvida no processo não é de todo compreendida, apesar das diversas teorias já propostas. São apresentados três casos de hemorragia á distancia da área cirúrgica, no pós-operatório de dois pacientes portadores de meningeoma do seio cavernoso e de um submetido à clipagem de aneurisma intracraniano.

Pseudoaneurisma da artéria carótida interna após ressecção transesfenoidal de macroadenoma hipofisário. Uma proposta de tratamento endovascular / Internal carotid pseudoaneurysm after transsphenoidal resection of a pituitary adenoma: an endovascular approach model

É apresentado um caso de pseudoaneurisma de artériacarótida interna após ressecção endoscópica transnasaltransesfenoidal de um adenoma de hipófise, com uma proposta de tratamento endovascular: como o paciente tornou-sesintomático no teste de oclusão da artéria carótida interna,um modelo alternativo - endovascular - foi proposto,consistindo no uso de molas e de um Stent vascular colocadoadjacente à luz do pseudoaneurisma.Após uma grave manifestação clínica, consistindo emhemorragia nasal maciça, o paciente evoluiu satisfatoriamenteapós o tratamento.