Neurovascular Compression Syndrome of the Eighth Cranial Nerve. Can the Site of Compression Explain the Symptoms?

Summary  Considerable skepticism still exists concerning the concept of neurovascular compression (NVC) syndromes of the eighth cranial nerve (8th N). If such syndromes exist, the sites of compression of the nerve must explain the symptoms encountered. We recorded compound action potentials of the cochlear nerve (CCAPs) during neurovascular decompression (NVD) to examine the topography of the three components of the 8th N. The sites of compression of the 8th N in cases of NVC syndrome confirmed at surgery were superimposed on the topography of the CN and vestibular nerve (VN) in order to determine the relationship between the sites of compression and the symptoms. CCAPs were clearly and consistently recorded on the caudal surface of the 8th N along the midline. In patients with vertigo and tinnitus there was vascular compression of the rostro-ventral (VN) and caudal surface (CN) of the nerve, respectively. In patients with both vertigo and tinnitus, there was compression of both VN and CN. Our findings clearly demonstrate that the symptoms of NVC of the 8th N depend on the part of the nerve that is compressed by blood vessels, and they support the concept of NVC syndrome of the 8th N.     

Safe handling of veins in the pineal region—a mixed method study

Neurosurgical Review - Surgical experience in pineal surgery is largely confined to a few experienced surgeons and may be lost when they stop their practice. The objective of this study is to...     

Posterior cranial distraction in the treatment of craniosynostosis—effects on intracranial volume

Background

Posterior cranial expansion has become increasingly practiced in the treatment of patients with craniosynostosis and a brachyturricephalic dysmorphology. This study aims to assess the gain in intracranial volume obtained by expanding the posterior cranial vault by internal distraction in these patients.

Methods

Three consecutive patients, one with Saethre–Chotzen syndrome, one with Apert syndrome, and one with nonsyndromic bicoronal synostosis underwent posterior cranial vault distraction using two pairs of distractors and a previously described accelerated distraction protocol. The procedure was performed at an average age of 5.3 (4.7–6.1)?months. Intracranial volumes were calculated with OsiriX© from computer tomographies obtained prior to placement and removal of distractors.

Results

The average gain in total intracranial volume was 21 (14–29)?%. The volume of the anterior cranial fossa was increased by an average of 22.3 (4–41)?%. However, the volume increase of the anterior cranial cavity had only a minor contribution to the total intracranial volume expansion.

Conclusions

Posterior cranial vault expansion with internal distractors has the potential to efficiently increase the volume of the intracranial cavity. From this small series, it appears that the volume gain is large, albeit variable, and that some remodeling may occur in the anterior cranium. Level of evidence: Level V, therapeutic study     

Unrecognized internal jugular vein obstruction: cause of fatal intracranial hypertension after tracheostomy?

We report an unusual case of fatal intracranial hypertension following tracheostomy due to the obstruction of the internal jugular veins (left side: thrombosis after central venous cannulation, right side: hypoplastic vein) and their collaterals. Principal cerebral outflow through the internal jugular veins can be substituted by the internal and external vertebral vein plexus because blood drains from the brain by two major routes: the internal jugular veins and the vertebral venous plexus. We suggest transcranial color-coded duplex sonography as a simple bedside method to detect patients with significant reduction of venous drainage who are at risk of developing massive cerebral venous congestion as a result of reduced intracranial elastance.     

Surgical treatment of brain tumor coexisted with intracranial aneurysm—case series and review of the literature

Coexistence of brain tumor and intracranial aneurysm was previously considered as an uncommon phenomenon. Actually it is not rare in neurosurgical procedures, and its incidence rate may be underestimated. Furthermore, there remains a lack of consensus regarding numerous aspects of its clinical management. We performed a retrospective study of 12 cases of coexistent brain tumor and intracranial aneurysm in our database. Then a systematic PubMed search of English-language literature published between 1970 and 2012 was carried out using the keywords: “brain tumor” and “intracranial aneurysm” in combination with “associate” or “coexist.” A consensus panel of neurosurgeons, anesthetists, interventional neurologists, and intensivests reviewed this information and proposed a treatment strategy. In the majority of patients, clinical symptoms were caused by tumor growth, whereas aneurysm rupture was seen only in a few cases. Meningioma was the commonest tumor associated with aneurysm. In most patients, both lesions occurred within the adjacent area. Treatment of both pathologies in one session was performed in most patients. All of our patients were alive within the period of follow-up. Coexistence of brain tumor and intracranial aneurysm may be a coincidence. The treatment strategy should be designed according to the conditions of tumor and aneurysm, locations of both lesions, and pathologic nature of tumor.     

Are viral infections the cause of leukocytospermia?

Leukocytospermia is defined as a leukocyte count of more than 1 x 106 ml-1 ejaculate. It may be a symptom of male accessory gland infection, but is also observed in up to 10% of asymptomatic patients presenting for infertility work-up. Pathogenic bacteria are not present in all of these semen samples. We attempted to find evidence for infection with cytomegalovirus, Epstein-Barr virus and herpes simplex virus by determining antibodies in serum in 130 patients with, and 80 patients without, leukocytospermia and by polymerase chain reaction in 50 further patients and controls. All semen samples with or without leukocytospermia were free from clinically significant concentrations of pathogenic bacteria. Only IgM antibodies against HSV were found more frequently in patients with leukocytospermia than in the controls (10.8 and 1.25%, respectively). All other virus antibody findings showed an equal frequency in both groups. The determination of HSV DNA in 50 further semen samples with, and 50 samples without, leukocytospermia revealed no positive results. Although our study indicates an association of herpes virus infection and leukocytospermia in 10% of cases, the mechanism of association is to be clarified.     

What was the cause of Nietzsche's dementia?

Many scholars have argued that Nietzsche's dementia was caused by syphilis. A careful review of the evidence suggests that this consensus is probably incorrect. The syphilis hypothesis is not compatible with most of the evidence available. Other hypotheses--such as slowly growing right-sided retro-orbital meningioma--provide a more plausible fit to the evidence.     

Can phlebectomy be deferred in the treatment of varicose veins?

OBJECTIVE: This study was designed to observe the clinical sequelae of varicose veins after great saphenous vein (GSV) ablation and to assess possible predictability of spontaneous varicose vein regression. METHODS: Patients with symptomatic varicose veins secondary to GSV insufficiency treated with radiofrequency ablation (RFA) were enrolled in the study. Up to five of the largest varicose veins in each limb were mapped, sized, and documented before RFA. No varicose vein was treated either at the time of RFA or within 6 months postoperatively. Varicose vein status was recorded at follow-up visits. RESULTS: Fifty-four limbs in 45 patients were included. A total of 222 varicose veins were documented before RFA (4.1 +/- 1.1 varicose veins per limb) with an average size of 11.4 +/- 3.7 mm. During the follow-up period, complete resolution of visible varicose veins was seen in 13% of limbs after RFA alone, and 63 (28.4%) varicose veins spontaneously resolved. A further 88.7% (141/159) of varicose veins decreased in size an average of 34.6% (4.3 +/- 3.4 mm). Preoperatively, 19.4% of varicose veins were above the knee and 75.7% were below the knee. Complete varicose vein resolution was 41.9% (18/43) above the knee and 25.6% (43/168) below the knee. For the above-knee varicose veins, 88.4% (38/43) were located medially, and all the resolved ones (47.4%, 18/38) were medial varicose veins. Resolution rates of the 168 below-knee varicose veins were 30.6% (33/108) of medial, 23.1% (6/26) of anterior, 20.0% (3/15) of lateral, and 5.3% (1/19) of posterior. CONCLUSIONS: Great saphenous vein ablation resulted in subsequent resolution or regression of many lower-limb visible varicose veins. With further study, the predictability of varicose vein regression may perhaps be increased, which can then direct the treatment strategy to further leverage the advantages of minimally invasive endovenous procedures.     

Sole stenting of large and giant intracranial aneurysms with self-expanding intracranial stents—limits and complications

Background  

Intracranial aneurysms may be difficult for endovascular treatment due to size, fusiform shape, or wide neck. In such patients, intracranial stents are used to support the coils in the aneurysm sac, or they may be used as a sole stenting technique to divert the blood flow without coils. The aim of this paper is to contribute to the existing data by reviewing the risks of sole stenting of large and giant aneurysms.     

What's new in the management of complex tibial plateau fractures?

The management of complex tibial plateau fractures is ever evolving. The severity of the injury to the surrounding soft tissues influences the timing and the method of fixation. Minimal invasive techniques continue to dominate our philosophy of reduction and reconstruction whereas augmentation of depressed intra-articular fragments remains an accepted strategy to maintain reduction and prevent secondary collapse. Locking plates, conventional plates and fine wire fixators all have been used successfully with satisfactory outcomes. In this article we report on the latest advances made in the management of these complex injuries.     

Biomechanical comparison of fixation of type-I fractures of the lateral tibial plateau. Is the antiglide screw effective?

Type-I fractures of the lateral tibial plateau were simulated by osteotomy in 18 pairs of unembalmed cadaver tibiae. One fracture of each pair was fixed with two lag screws whereas the contralateral site was stabilised with three lag screws, or two lag screws plus an antiglide screw. The lateral plateau was displaced downwards using a servohydraulic materials testing machine and the resulting force and articular surface gap were recorded. Yield load was defined as the maximum load needed to create a 2.0 mm articular offset at the fracture line. The yield loads of the three-lag-screw (307 +/- 240 N) and antiglide constructs (342 +/- 249 N) were not significantly different from their two-screw control constructs (231 +/- 227 and 289 +/- 245 N, respectively). We concluded that adding an antiglide screw or a third lag screw did not provide any biomechanical advantage in stabilising these fractures.     

Schwannoma of the tibial nerve sheath as a cause of tarsal tunnel syndrome—A case study

A schwannoma is a benign, encapsulated and non-invasive tumour whose origin is derived from Schwann cells. Its incidence in the foot and ankle is rare. The etiology, incidence, clinical presentation, histology, differential diagnoses and surgical treatment are discussed. The authors present a case of a schwannoma of the tibial nerve sheath causing tarsal tunnel syndrome of the foot. The diagnosis in this case was delayed for eight years, which unfortunately is not uncommon with pedal schwannomas.     

Jejunal diverticula — a rare cause of intestinal perforation

Jejunal diverticuli is a extremely rare entity. We report a case of jejunal diverticulum as a cause of perforation peritonitis, which has been managed by resection anastomosis. This study is important from the perspective that clear cut guidelines for managment of jejunal perforation are not available in litreture.     

Thickening of the synovium of the digital flexor tendons: cause or consequence of the carpal tunnel syndrome?

Using a monofilament wire suture, the radial and ulnar edges of the flexor retinaculum were approximated in 14 white New Zealand rabbits. As a result, the volume of the carpal tunnel was diminished, and "carpal tunnel syndrome" was produced. At various intervals after this procedure the animals were sacrificed. The median nerve and all the digital flexor tendons passing through the carpal tunnel were excised "en bloc", and sent for histological examination. Vascular proliferation with perivascular round cell infiltration and oedema, and large areas of fibroblastic activity were observed around the digital flexor tendons. This was probably due to increased vascular permeability secondary to ischaemic endothelial damage. These findings are similar to those observed in the synovium of patients operated on for carpal tunnel syndrome.     

Does donor cause of death affect the outcome of lung transplantation?

BACKGROUND: Accumulating evidence suggests that the donor's cause of death may influence posttransplantation allograft function. We conducted a retrospective analysis of our adult lung transplant experience to investigate the influence of donor traumatic brain injury versus nontraumatic brain injury on posttransplantation outcome. METHODS: We retrospectively reviewed donor records and recipient medical charts for 500 consecutive lung transplants performed between July 1988 and December 1999. Recipient follow-up was complete, with a minimum follow-up of 1 year of survival. RESULTS: There were 295 and 205 donors in the traumatic and nontraumatic brain injury groups, respectively. Young male donors predominated in the traumatic brain injury group. Recipients receiving donor lungs from the traumatic and nontraumatic brain injury groups did not differ by age, sex, diagnosis, type of transplant (single-lung versus double-lung) or requirement for pretransplantation mechanical ventilatory assistance. Recipients did not differ in immediate or 24-hour PaO (2)/inspired oxygen ratio, ventilation time, hospital stay, hospital mortality, or overall survival. Recipients of organs from donors who died of traumatic brain injury showed a higher severity and frequency of rejection episodes during the first year after transplantation. Freedoms from bronchiolitis obliterans syndrome at 5 years were 34.5% and 50.8% for recipients of organs from donors who died of traumatic and nontraumatic brain injury, respectively (P =.002). CONCLUSIONS: The cause of donor brain death does not appear to influence early results of lung transplantation. Traumatic brain injury, or some phenomenon associated with it, may predispose a transplanted lung and its recipient toward more severe early rejection episodes and subsequent development of bronchiolitis obliterans syndrome.