Cervical Oblique Corpectomy: Revitalizing the Underused Surgical Approach With Step-By-Step Simulation in Cadavers.

ABSTRACT: Recently, the World Federation of Neurosurgical Societies Spine committee recommended that additional research on cost-benefit analysis of various surgical approaches for cervical spondylotic myelopathy be carried out and their efficacy with long-term outcomes be compared. Unfortunately, it is highly probable that the oblique corpectomy (OC) will not be included in cost-benefit investigations due to its infrequent application by neurosurgeons dealing with the spine. In this cadaveric study, head and necks of 5 adult human cadavers stained with colored latex and preserved in 70% alcohol solution were dissected under a table-mounted surgical microscope using 3× to 40× magnifications. The OC approach was performed to simulate real surgery, and the neurovascular structures encountered during the procedure and their relations with each other were examined. Oblique corpectomy was performed unilaterally, although neck dissections were performed bilaterally on 10 sides in all 5 cadavers. At each stage of the dissection, multiple three-dimensional photographs were obtained from different angles and distances. For an optimal OC, both the anterior spinal cord must be sufficiently decompressed and sufficient bone must be left in place to prevent instability in the cervical spine. Oblique corpectomy is a valid and potentially low cost alternative to other anterior and posterior approaches in the surgical treatment of cervical spondylotic myelopathy. However, meticulous cadaver studies are essential before starting real surgical practice on patients in order to perform it effectively and to avoid the risks of the technique.

The probability of iatrogenic major vascular injury in lumbar discectomy.

Purpose: To estimate the frequency of iatrogenic injury of major vascular structures during lumbar discectomy.Materials and methods: The medical records of patients who underwent surgery for lumbar disc herniation at our neurosurgical clinic between April 2000 and April 2016 were retrospectively reviewed. Patients with intraoperative iatrogenic vascular injury were identified by reading the surgical notes and the post-operative progress records of patients who had undergone lumbar discectomy. The standard calculation of the incidence of iatrogenic major vascular injury in lumbar discectomy was used to analyse the data. The formula for estimating the standard probability by calculating the incidence rate is: [Formula: see text]=n/N, where [Formula: see text] is the estimated probability, n is the number of events and N is the total number of cases. The standard error of this estimate is SE[Formula: see text]=[Formula: see text]Results: During the study period, 2498 patients underwent lumbar discectomy at one or more levels of the lumbar spine. The operations were performed by more than 40 different neurosurgeons or surgical residents. More than 95% of the operations were done under a surgical microscope. Two cases were found to have iatrogenic major vascular injuries. The standard frequentist estimate of the probability, [Formula: see text] (risk-per-case), of iatrogenic major vascular injuries in lumbar discectomy was: [Formula: see text]=2/2498 = 0.0008 (0.08%). The standard error of this estimate was: [Formula: see text]=[Formula: see text]=0.000566 = 10-4 (5.66) (95% confidence interval for true p = 10-4 (801)±(1.96)×10-3 (566)).Conclusions: In this study, the incidence of iatrogenic major vascular injuries in lumbar discectomy was 1 in 1249 operations (0.08%). If utmost care is taken, at least some of these iatrogenic intraoperative vascular complications can be avoided or more rapidly treated, and the lives of such patients can be saved.

A retrospective comparison analysis of results of drug-coated balloon versus plain balloon angioplasty in treatment of juxta-anastomotic de novo stenosis of radiocephalic arteriovenous fistulas.

BACKGROUND: Juxta-anastomotic stenosis is a common issue of arteriovenous fistulas. We aimed to evaluate the results of percutaneous transluminal angioplasty with drug-coated balloon versus plain balloon for the treatment of juxta-anastomotic stenoses of mature but failing distal radiocephalic arteriovenous fistulas. METHODS: A total of 80 patients with a juxta-anastomotic stenosis of distal radiocephalic arteriovenous fistula in our clinic between January 2016 and September 2017 were retrospectively analyzed. Patients were divided into two groups according to the type of treatment as drug-coated balloon - percutaneous transluminal angioplasty (n = 44) and plain balloon - percutaneous transluminal angioplasty (n = 43). Intra- and post-procedural data were recorded. Target lesion primary patency rate was evaluated at 6 and 12 months. Of all patients, 48 were females and 39 were males with a mean age of 56.3 ± 10.4 (range, 24-75) years. Both groups had mature fistulas, and the mean age of fistula was 11.3 ± 9.1 months in the drug-coated balloon - percutaneous transluminal angioplasty group and 10.3 ± 8.8 months in the plain balloon - percutaneous transluminal angioplasty group (p = 0.24). RESULTS: There was no significant difference in the target lesion stenosis rate and the median lesion length between the groups. Technical and clinical success were achieved in both groups. Target lesion primary patency was similar at 6 months between the two groups (93.1% vs 81.3%, respectively; p = 0.14) but significantly higher for the drug-coated balloon - percutaneous transluminal angioplasty group at 12 months (81.8% vs 51.1%, respectively; p = 0.01). CONCLUSION: Our study results suggest that the use of drug-coated balloon combined with percutaneous transluminal angioplasty is an effective treatment for juxta-anastomotic stenoses of mature but failing distal radiocephalic arteriovenous fistulas with significantly improved target lesion primary patency rates and reduced need for juxta-anastomotic reinterventions.

A New Perspective in Comparing Injuries Caused by Short-Duration External and Internal Forces in Saphenous Vein.

BACKGROUND: Great saphenous vein (GSV) graft failure is one of the major reasons for repeat bypass grafting. A comparison of the effects of simultaneous, short-duration, externally squeezing and internally distending forces on the same segment of ex-vivo human GSV has not yet been published, although similar studies have compared the experimental injury of different ex-vivo human veins. METHODS: Approximately 8-cm-long segments of GSV were harvested from each of the 15 patients. For each specimen, one end of the vein piece was occluded at a distance of 1 cm with an external cross-clamp for 5 min and the other end was similarly occluded at a distance of 1 cm by an endoluminal balloon. The middle sections of the veins, which were not occluded by any means, were taken as the control group. Two histologists, who were blinded to the groups, graded the hematoxylin and eosin (H&E) and Weigert-Van Gieson (WVG) stained sections semi-quantitatively and performed the histomorphometric measurements. RESULTS: The result of the histopathological evaluation of the intima layer showed that the microscopic scoring of lesions in the balloon group was significantly higher than that in the clamp and control groups (5.16 ± 1.32, 3.83 ± 0.75, and 1.00 ± 1.09, respectively; P < .001). In the adventitia layer, this level of scoring increased more in the clamp group than in the balloon and control groups (5.16 ± 1.16, 3.00 ± 0.89, and 0.16 ± 0.40, respectively, P < .001). CONCLUSION: Both the endoluminal balloon and external clamp techniques have harmful effects on the vein wall. Studying different kind of forces on different veins cannot provide us with reliable comparisons.

A New Method for Determining the Level of the Carotid Artery Bifurcation.

Exact localization of the bifurcation of the common carotid artery using skin surface landmarks is important for various diagnostic and therapeutic purposes, including emergency cases. Traditional methods have confirmed their accuracy in only a certain percentage of cases and there are inconsistencies among various publications. The cervical computed tomography-angiographic examinations for any diagnostic purpose between June 2017 and December, 2017 in the authors' hospital were examined. Measurements were performed for (MT-CB) and (MT-SE) distances and the results were recorded [MT = The tip of the mastoid process; CB = common carotid artery bifurcation; SE = sternal extremity of the clavicle]. Cervical computed tomography angiography was found in the records of 91 patients in the 6-month period between June 2017 and December 2017. After exclusion criteria were applied, a total of 116 carotid bifurcation levels on the right and left sides were measured in 58 patients. The mean MT-CB distance was 6.29 ±â€Š0.9 cm (range: 2.9-8.4 cm). The mean distance between MT and SE was 15.3 ±â€Š1.7 cm (range: 9.9-19.0 cm). The (MT-CB): (MT-SE) ratios ranged from 29% to 51% with a mean of 41 ±â€Š4.2% (95% CI: 39.88%-42.10%) and a median of 41.1% (P < 0.05) (Kolmogorov-Smirnov test). The distance ratio values did not change significantly according to age and gender (respectively P = 0.341, P = 0.093). These results show that the CB is usually located at two-fifths of the distance from the mastoid tip to the sternal extremity of the clavicle and closer to the mastoid tip.

Surgical technique for the protection of the cervical sympathetic trunk in anterolateral oblique corpectomy: A new cadaveric demonstration.

The cervical oblique corpectomy (OC) approach has the advantages of no grafting or instrumentation necessities and theoretically maintains natural neck motions. However, the risk of cervical sympathetic trunk (CST) injury and Horner's syndrome is one of the main difficulties of this demanding surgical approach. The upper necks of 3 adult human cadavers (6 sides) were dissected under a Zeiss surgical microscope. OC was performed in a stepwise manner to simulate the surgical procedure. We specifically studied the technique of the protection of the CST during the cervical OC approach. The superior ganglion of the cervical sympathetic chain is located under the prevertebral fascia over the longus capitis muscle at the level of C3 transverse process, while the CST is situated under the prevertebral fascia over the longus colli muscle. The CST courses obliquely from superolateral to inferomedial. The ganglia and CST are carefully dissected; the fascia of the longus colli muscle is cut medially, preferably in the midline over the vertebrae, and the fascia lifted up. Then, the aponeurotic flap is gently retracted laterally to cover the sympathetic chain safely and secured with a 3/0 suture laterally. Preservation of the CST while performing cervical OC is essential to avoid postoperative Horner's syndrome. The placement of self-retaining retractors, particularly inferiorly, where the sympathetic chain is located more medially, is probably the main cause of its injury. Further studies are needed documenting the incidence of Horner's syndrome in the application of this technique to live patients.

Surgical Pitfalls in Carotid Endarterectomy: A New Step-By-Step Approach.

Carotid endarterectomy (CEA) is a surgical intervention that may prevent stroke in asymptomatic and symptomatic patients. Our aim was to examine the microsurgical anatomy of carotid artery and other related neurovascular structures to summarize the CEA that is currently applied in ideal conditions. The upper necks of 2 adult cadavers (4 sides) were dissected using ×3 to ×40 magnification. The common carotid artery, external carotid artery (ECA), and internal carotid artery were exposed and examined. The surgical steps of CEA were described using 3-D cadaveric photos and computed tomography angiographic pictures obtained with help of OsiriX imaging software program. Segregating certain neurovascular and muscular structures in the course of CEA significantly increased the exposure. The division of facial vein allowed for internal jugular vein to be mobilized more laterally and dividing the posterior belly of digastric muscle resulted in an additional dorsal exposure of almost 2 cm. Isolating the ansa cervicalis that pulls hypoglossal nerve inferiorly allowed hypoglossal nerve to be released safely medially. The locations of the ECA branches alter depending on their anatomical variations. The hypoglossal nerve, glossopharyngeal nerve, and accessory nerve pierce the fascia of the upper part of the carotid sheath and they are vulnerable to injury because of their distinct courses along the surgical route. Surgical exposure in CEA requires meticulous dissection and detailed knowledge of microsurgical anatomy of the neck region to avoid neurovascular injuries and to determine the necessary surgical maneuvers in cases with neurovascular variations.

Acute pancreatitis after coronary artery bypass surgery treated by plasmapheresis.

Acute pancreatitis (AP) is a common disorder and an important cause of morbidity and mortality. There are different causes of AP, including gallstones and excessive alcohol consumption. AP after coronary artery bypass grafting (CABG) surgery is seen less frequently but it is associated with a high mortality rate due to its atypical and misleading symptoms. Supportive treatment, pain management, and treatment of complications are used in the treatment of AP. The treatment of hypertriglyceridemia-induced pancreatitis is plasmapheresis, which is an extracorporeal separation of blood components to assist in the removal of inflammatory mediators. Here we present the case of a 60-year-old male patient who developed severe AP (Ranson Score: 6) without hypertriglyceridemia after CABG. The patient received supportive treatment, but the response to conventional therapy was not predictable. Thus, plasmapheresis was started, and the patient was treated with plasmapheresis successfully. The use of plasmapheresis in patients with this condition is a new treatment modality as far as we know. This case illustrates the efficient and safe use of the plasmapheresis treatment modality in a patient with AP without hypertriglyceridemia.