SANS Oktober 2013 Flashcards
Setelah berapa bulankah dapat dianggap suatu kontraindikasi untuk melakukan transfer saraf dari nervus tibial kepada nervus deep peroneal pada pasien dengan foot drop ?
A. 10 B. 8 C. 6 D. 12 E. 14
D. 12
Muscle denervation time greater than 12 months has been considered a contraindication to the performance of nerve transfer for foot drop. Traditionally, surgery is indicated for cases presenting with closed injury to the peroneal nerve in which no sign of recovery had been noted eight months after the trauma and for patients with sciatic nerve injuries (the peroneal division) admitted six months following the trauma. Other contraindications include paralysis or dysfunction of the tibial nerve, and the presence of neuromuscular or metabolic disorders affecting the function of the limbs. Soleus muscle function is not fundamental in ankle movement
Faktor apakah yang berkaitan dengan kejadian outcome buruk yang mengikuti transfer nervus tibial kepada nervus deep peroneal ?
A. Mekanisme injury B. Gender C. Umur D. Jaringan parut interneural extensive E. Penggunaan saraf donor dengan fungsi agonis
D. Jaringan parut interneural extensive
Extensive interneural scar tissue has been linked to poor outcome for nerve transfer. In a recent retrospective study, Flores et al provide the following explanations for poor outcomes following tibial nerve to deep peroneal nerve transfer: extensive intraneural scar tissue, an increased amount of connective tissue, and a misbalance of the power of the muscles between the ventral and dorsal compartments of the leg; the use of a donor nerve that acts as an antagonist to the function that it is intended to recover; an insufficient number of available donor axons in the tibial nerve; and interference with the mechanism of gait associated with central plasticity resulting in lack of voluntary function. Neither patients’ demographics nor the mechanism of injury have been shown to affect the outcomes. The authors’ surgical technique specifically confers a tensionless anastomosis, so that is unlikely to be the cause of the failures.
Apakah yang menjadi pilihan bedah terbaik untuk pasien dengan foot drop sekunder dari trauma nervus sciatic atau trauma nervus peroneal ?
A.Posterior tibial tendon to dorsum of the foot transfer
B. Tibial to deep peroneal nerve transfer
C. Nerve reconstrucion with long grafts
D. Soleus tendon to dorsum of the foot transfer
A.Posterior tibial tendon to dorsum of the foot transfer
Tendon transfers, such as the transfer of the posterior tibialis tendon to the dorsum of the foot, have been suggested as the best surgical option for foot drop secondary to traumatic nerve injury of the sciatic or peroneal nerves. Outcomes obtained following the transfer of a healthy motor branch of the tibial nerve (the nerve of the soleus muscle) to the motor fascicle of the peroneal nerve responsible for the innervation of ankle dorsiflexion (the deep peroneal nerve) have been inconsistent. Although nerve reconstruction is indicated in some cases, poor outcomes are frequently associated with such procedures, especially if long grafts are needed. Soleus muscle tendon hasn’t been used as a donor in foot drop.
Menurut American Heart Association, pasien dengan stenosis carotid symptomatic seharusnya dilakukan carotid revascularization (CAS / CEA) apabila noninvasive imaging memperlihatkan penyempitan dari artery carotid internal ipsilateral pada tingkat berapa persen minimal ?
A. 65 % B. 60 % C. 55 % D. 70 % E. 75 %
D. 70 %
According to the NASCET (North American Symptomatic Carotid Endarterectomy) Trial, symptomatic (non-disabling stroke, TIA, amaurosis fugax) patients with high-grade (>70%) stenosis of the ICA, as detected by non-invasive imaging, benefit from CEA. These patients obtained a 17% absolute reduction in risk of ipsilateral stroke at 2 years compared to those treated medically. The CREST (Carotid Revascularization Endarterectomy vs. Stenting) Trial demonstrated an insignificant difference between CEA and CAS in similar patients. These data led to a Class IA recommendation for revascularization (CEA or CAS) in these patients by the AHA.
Pada pasien yang sedang dilakukan tindakan terapi untuk arteriovenous malformations (AVMs) intracranial, manakah dari variabel berikut yang memiliki efek terkuat pada outcome fungsional ?
A. Modalitas terapi B. Spetzler Martin Grade C. Obliterasi AVM komplit D. Riwayat pendarahan E. Embolisasi Adjunctive
C. Obliterasi AVM komplit
Complete AVM obliteration is strongly associated with restoration of functional activities. In the recent study by Huang et al, of all of the clinical factors considered, only complete AVM obliteration was clinically significant. While surgical resection typically results in immediate complete obliteration, obliteration following radiosurgery takes several years and is not always complete. This can impact the rate of seizure freedom and the incidence of new seizures following treatment. Both AVM persistence and the potential for further hemorrhage in the setting of an incompletely obliterated AVM may contribute to the functional activity of this patient population
Pada pasien dengan stenosis carotid, berapakah kira-kira persetase 4-year rate dari kejadian efek samping serius (stroke, myocardial infarction, death) dari tindakan carotid artery stenting atau carotid endarterectomy ?
A. 9 % B. 7 % C. 5 % D. 11 % E. 13 %
B. 7 %
The CREST (Carotid Revascularization Endarterectomy vs. Stenting) Trial randomized patients with symptomatic and asymptomatic carotid stenosis to either carotid artery stenting (CAS) or carotid endarterectomy (CEA) and reported a 4-year risk of major adverse events (stroke, MI, death) was 7.2% in the CAS group and 6.8% in the CEA group, an insignificant difference.
Perioperative rates of major adverse events are slightly lower. The CREST trial showed rates of approximately 6% (6.7% after CAS and 5.4% after CEA) in symptomatic patients and approximately 3.5% (3.5% after CAS ad 3.6% after CEA) in asymptomatic patients. A recent single-institutional case series of CAS for symptomatic and asymptomatic patients showed rates of 4.2% and 1.3%, respectively.
Pada pasien dengan intracranial arteriovenous malformations (AVMs) yang memperlihatkan gejala kejang, manakah dari faktor berikut yang dapat berkontribusi pada perbaikan kontrol kejang ?
A. Lokasi eloquent dari AVM B. Stereotactic radiosurgery C. Reseksi bedah pada AVM D. Embolisasi adjunctive E. Riwayat pendarahan
C. Reseksi bedah pada AVM
In patients with intracranial AVMs and a history of seizures, treatment with surgical resection is associated with an increased likelihood of seizure freedom following treatment when compared with treatment with radiosurgery. A recent study showed that 59% of patients with a prior history of seizures achieved seizure freedom following surgical resection, whereas only 27% who were treated with SRS achieved seizure freedom. Univariate analysis suggested that an AVM’s eloquent location was also associated with seizure persistence following surgery. History of prior hemorrhage and adjunctive use of embolization were not associated with seizure freedom. While not all studies have suggested a treatment effect in association with seizure freedom (Josephson et al), Hyun et al have also suggested increased seizure freedom with surgical resection of AVMs in patients with prior seizure histories. This would fit with the obliteration of the epileptogenic focus assisting with ultimate seizure control in this patient population.
Pada pasien dengan intracranial arteriovenous malformations (AVMs) tanpa riwayat kejang, faktor apakah yang berkaitan dengan insidensi rendah akan kejang di masa depan ?
A. Stereotactic radiosurgery B. Lokasi lobus frontal C. Reseksi bedah D. Embolisasi E. Riwayat pendarahan
A. Stereotactic radiosurgery
In patients with intracranial AVMs without a history of seizures, radiosurgial treatment is associated with a lower incidence of post treatment seizures compared to surgical resection. In a study by Huang et al., a specific analysis considered patients treated for intracranial AVMs who did not have a history of seizures prior to treatment. In this patient population, a total of 18.4% of patients presented with de novo seizures following treatment. While 36% of patients who underwent surgery had de novo seizures, only 9.7% of those who underwent SRS presented with new seizure activity following treatment. In multivariate analysis in this series both frontal lobe location and surgical resection were associated with an increased risk of seizures. The increased seizure incidence in surgically treated patients was felt to be most likely associated with the creation of new epileptogenic foci through manipulation of the brain at the time of surgery.
Emoblization, duration of follow up, and a history of prior hemorrhage have not been shown to affect the incidence of seizures.
Apakah faktor utama yang membuat stroke center yang menangani volume tinggi dari jumlah pasien dengan carotid stenting or endarterectomy memiliki outcome lebih baik dibanding dengan stroke center yang volume jumlah pasiennya sedikit ?
A. Peningkatan edukasi publik
B. Jarak tempuh perjalanan ambulans lebih dekat
C. Pengalaman operator meningkat
D. Availabilitas yang lebih baik untuk trombolisis IV
E. Menurunnya angka dari komorbiditas pasien
C. Pengalaman operator meningkat
Operator experience plays a major role in improving outcomes and reducing complication rates across a range of disciplines including revascularization of carotid stenosis. In the original NASCET (North American Symptomatic Carotid Endarterectomy) Trial publication, the authors emphasized the importance of including only surgeons with “a high level of expertise” in the trial. They caution that their results are only applicable if CEA is performed by similarly skilled operators. If the surgeon’s rate of perioperative major stroke or death exceeded the 2.1% observed in that study, the observed benefits of CEA would diminish, and a major complication rate of >10% would erase the benefits altogether.
The American Heart Association therefore notes that its Class IA recommendation for revascularization (CEA or CAS) for symptomatic patients with stenosis >70% only applies for experienced operators who have performed >20 procedures with proper technique and low complication rate.
A retrospective case series of CAS for carotid stenosis from a high-volume institution reported notably low perioperative rates of major adverse events (any stroke, MI, death) in 474 patients. The overall rate was 2.7% (0.9% for stroke, 0.6% for MI, and 1.1% for death). The authors attributed their low complication rates to the high volume of patients treated at their center and the resultant procedural experience.
