Thoracoscopic Microdiscectomy with Preservation of Rib and Costovertebral Joint.

INTRODUCTION: Thoracic disc herniations (TDH) may cause major morbidity. While thoracoscopic microdiscectomy (TMD) is an excellent technique, postoperative band-like pain is an important drawback. MATERIAL AND METHODS: We performed 181 consecutive TMDs (including 39 high-risk cases) with preservation of rib and costovertebral joint (CVJ). We shave a few mm of the rib, drill straight to target, and avoid opening the canal before the TDH is completely free and (in case of giant TDHs) internally debulked, creating initial decompression and limiting epidural venous oozing. Subsequently, we gently mobilize and remove the residual TDH while avoiding leverage. RESULTS: Skin-to-skin time was <90' in 64, 90-120' in 48, >120' in 20, unknown in 10, and 162' mean in 39 high-risk procedures. Blood loss was <100 mL in 76, <250 mL in 48, and 537 mL mean in 39 high-risk procedures. The technique was successfully applied in all (including nine dural repairs) without a single conversion. We observed an increased neurological deficit in two (1.1%) and inadequate decompression in merely one (wrong level). Complications (mainly pulmonary) were few and managed conservatively, except for a segmental artery pseudoaneurysm treated endovascularly. We observed a substantial decrease in acute and chronic postoperative pain. DISCUSSION: The technique is fast, straightforward, minimizes bone resection and blood loss, improves orientation, safely and effectively deals with any TDH, and prevents postoperative band-like pain as the CVJ is preserved. CONCLUSION: We hope this technique will find broader acceptance among a new generation of spine surgeons to benefit patients suffering TDH-related myelopathy or merely intractable pain.

Transsphenoidal treatment of secondary empty sella syndrome using low field strength intraoperative MRI: case report.

BACKGROUND: The purpose of this study is to demonstrate the added value of intraoperative MRI in treating secondary empty sella syndrome. CASE REPORT: We describe the case of a 66-year-old woman who was diagnosed with a prolactinoma stage IIIb. During treatment with cabergoline she presented with a secondary empty sella syndrome resulting in visual symptoms. We performed intraoperative MRI-guided packing of the secondary empty sella. We explain why this is useful in surgical treatment of secondary empty sella syndrome. CONCLUSION: Intraoperative MRI helps to achieve adequate sellar packing while avoiding insufficient packing as well as overpacking.

Intraspinal dermoid and epidermoid tumors: report of 18 cases and reappraisal of the literature.

Intraspinal dermoid and epidermoid tumors are two histopathological subtypes of cutaneous inclusion tumors of the spine. This classification is based on obsolete embryological knowledge. In fact, according to current embryology, both tumor types consist of ectodermal derivatives. Therefore, we hypothesized that dermoid and epidermoid tumors do not differ in clinical practice. To explore this hypothesis, we studied the clinical, radiological and intraoperative findings of 18 patients, and related these findings to the histopathological characteristics of the tumor. No differences were found between dermoid and epidermoid tumors regarding clinical presentation, radiological examination and outcome, while intraoperative diagnosis by the surgeon correlated with the histopathological diagnosis in only 8 of 18 cases. Therefore, the histopathological difference between intraspinal dermoid and epidermoid tumors is not important in clinical practice and should be avoided. A new nomenclature is proposed in which both tumor types are referred to as 'spinal cutaneous inclusion tumors'.

The spinal dermal-sinus-like stalk.

OBJECTS: In this study, a disjunction anomaly mimicking the spinal congenital dermal sinus (DS) is described. This anomaly is referred to as the dermal-sinus-like stalk. Dissimilarities between a true dermal sinus and a dermal-sinus-like stalk are discussed. CLINICAL MATERIAL: Three cases in which a spinal congenital dermal sinus was suspected are presented. A similar anatomical configuration, different from that of a dermal sinus, was found. All cases presented with a skin-covered dimple from which a solid tract was seen continuing intramedullary in two cases and intraspinally in one case. None of the patients presented with signs of infection or an associated dermoid-epidermoid tumor. Clinical, radiological, and surgical findings are discussed. A hypothesis is made on the pathological genesis of this malformation. CONCLUSION: A dermal-sinus-like stalk is a malformation similar to a spinal congenital dermal sinus but is not associated with DS-related complications. Despite important clinical, radiological, surgical, and histopathological differences, it is difficult to distinguish this malformation from a true DS based on clinical and radiological examination alone. Therefore, surgical intervention, at the time of diagnosis, is recommended in all cases.

Analysis of the success and failure of endoscopic third ventriculostomy in infants less than 1 year of age.

OBJECTIVES: In infants less than 1 year of age, the value of endoscopic third ventriculostomy (ETV) is controversial. It is believed to cause more morbidity and to have higher failure rates. We analyzed our data enlarging the reported pool of ETV outcome in infants less than 1 year of age. MATERIALS AND METHODS: We performed 12 ETVs in ten patients younger than 1 year of age. All patients had predominant supratentorial hydrocephalus. We defined ETV success as a shunt-free follow-up of at least 12 months, however, allowing re-ETV. CONCLUSION: ETV should be considered as initial treatment and carries low morbidity in these infants. As the immune system rapidly matures, postponing shunt implantation for several months or even weeks would make an ETV procedure worthwhile. On the other hand, as success probability rapidly increases 4 months after birth, re-ETV should always be considered first.

Anatomy and surgery of the infected dermal sinus of the lower spine.

OBJECT: Cases of infected dermal sinus are scarce and detailed surgical anatomical descriptions are hardly found in literature. The clinical, radiological, and surgical findings in four cases of an infected dermal sinus located at the lower spine are presented to elucidate the pathological anatomical configuration. CLINICAL MATERIAL: The first case showed two dermal sinuses with a parallel course extra- and intradurally, ending in a confluence of cavities connected to the conus. In this case, as well as in the fourth case, the signs and symptoms were those of meningitis. The second case presented with meningitis and a subdural empyema, while the third case presented with an intradermoid-intramedullary abscess at the junction between the DS and the conus. This child probably showed signs and symptoms of conus involvement as early as during pregnancy. CONCLUSION: The anatomy of the nervous elements in this congenital anomaly is heavily disturbed, more particularly in case of infection, due to extensive arachnoidal scarring. The latter renders dissection laborious and recognition of anatomical details difficult, resulting in complete excision of a dermal sinus in less than half of the cases. Despite their variability in presentation, most cases of an infected dermal sinus show similar characteristic features.

Differential effects of subthalamic nucleus stimulation in advanced Parkinson disease on reaction time performance.

The aim of the present study was to assess the effect of bilateral subthalamic nucleus (STN) stimulation and dopaminergic medication on speed of mental processing and motor function. Thirty-nine patients suffering from advanced Parkinson disease (PD) were operated on. Motor function and reaction time (RT) performance [simple RT (SRT) and complex RT (CRT)] were evaluated under four experimental conditions with stimulation (stim) and medication (med) on and off: stim-on/med-on, stim-on/med-off, stim-off/med-off and stim-off/med-on. In the last condition, the patients received either low medication (usual dose) or high medication (suprathreshold dose). STN stimulation improved the motor performance in the SRT and CRT tasks. Furthermore, STN deep brain stimulation (DBS) also improved response preparation as shown by the significant improvement of the RT performance in the SRT task. This effect of STN DBS on the RT performance in the SRT task was greater as compared with the CRT task. This is due to the more complex information processing that is required in the CRT task as compared to the SRT task. These data suggest that treatment of STN hyperactivity by DBS improves motor function, confirming earlier reports, but has a differential effect on cognitive functions. The STN seems to be an important modulator of cognitive processing and STN DBS can differentially affect motor and associative circuits.

The intermediate type split cord malformation: hypothesis and case report.

METHODS: A patient is described in which a complete osteofibrotic dorsally implanted septum was found in combination with a split cord malformation in a single dural tube. This case cannot be explained using the widely used theory as proposed by Pang et al. [Pang D, Dias MS, Ahab-Barmada M (1992) Split cord malformation, part I: A unified theory of embryogenesis for double spinal cord malformations. Neurosurgery 31:451-480] but must be regarded as a combination of type I and II split cord malformation. RESULTS: The authors state that all types of split cord malformation can be reduced to a single derailment during development, with various degrees of severity. CONCLUSIONS: The configuration of the malformation is determined by the way the median parts of the mesoderm come to development. Type I and II split cord malformation are not distinct entities.

Thalamus and penile erection.

Penile erection is a complex neurovascular event. The neuronal system involved is often divided into a spinal (generator) and supraspinal (controller) network. Little is known about the supraspinal control. The recent finding of changes in penile erection following deep brain stimulation of the thalamus in two patients has raised the question as to what extent the thalamus is involved in erectile function. The thalamus has generally been regarded as a group of relay nuclei that served as a 'gate' for sexual information from the spinal cord towards higher centres. Recent evidence, however, suggests a more integrated regulatory function. Our review of the literature from 1960 until 2003 revealed 13 reports describing original data (preclinical and clinical). Various thalamic regions, varying from the midline thalamus to the posterior thalamus, have been reported to be activated during erection. The majority of the reports, however, showed that mainly the mediodorsal (MD) nucleus and the centromedian-parafascicular nucleus (Cm-Pf complex) are involved in penile erection. MD is the second largest nuclear aggregation located within the medial part of the thalamus. Anatomically, the MD is closely related to the Cm-Pf complex. The Cm-Pf complex is one of the most important relay stations in which the anterolateral spinothalamic pathway is further processed. This pathway is thought to transmit peripheral sexual sensations. On the whole, the present data on the role of the thalamus in erection are far from complete and future experiments are required to delineate its involvement.

[Parinaud's syndrome as a sign of acute obstructive hydrocephalus: recovery after acute ventriculostomy]. / Het syndroom van Parinaud als teken van acute obstructieve hydrocefalus: herstel na acute ventriculostomie.

Paresis or palsy of upward vertical gaze, pupillary light-near dissociation and nystagmus retractorius with convergence, were present in a boy aged 16 years and a woman aged 30 years with an obstructive hydrocephalus due to an aqueductal stenosis as a consequence of a bacterial meningitis and in a woman aged 26 years and a man aged 47 years with an outlet obstruction of the fourth ventricle after a posterior fossa operation for a tumour in the fourth ventricle. All of the patients were suspected of having a drain dysfunction. They all underwent a third-ventriculocisternostomy after which their symptoms (partially) resolved. The presenting symptoms stated are the classical triad of Parinaud's syndrome. In addition to these there are less frequent symptoms such as bilateral eyelid retraction (Collier's sign) and convergence spasms. The syndrome is rare but has a significant mortality risk and a high morbidity rate if an obstructive hydrocephalus is not diagnosed and treated. An MRI scan of the cerebrum to detect obstructive hydrocephalus with dilation of the aqueduct is the diagnostic of choice. For an obstructive hydrocephalus with dilation of the aqueduct a third-ventriculocisternostomy is the treatment of choice.