Stefan Welschehold

Endoscopic endonasal pituitary surgery: Surgical and outcome analysis of 50 cases

OBJECTIVE Microsurgical transsphenoidal surgery for pituitary tumors has been standard therapy for decades and was established by Harvey Cushing in the early twentieth century. Today, endoscopy is increasingly accepted in the therapy of pituitary lesions. In this retrospective study, we analysed the surgical technique and outcome of 50 patients with pituitary lesions treated with an endoscopic endonasal trans-sphenoidal approach. METHODS Between January 2004 and July 2005, 50 patients (30 female and 20 male) with pituitary tumors were operated upon using an endoscopic endonasal trans-sphenoidal procedure without nasal speculum or postoperative nasal packing. The follow-up period ranged from 3 to 18 months. RESULTS All patients had normal airways through both nostrils immediately after extubation. Postoperative discomfort was minimal and hospitalization was 4-5 days. Three patients developed postoperative transient diabetes insipidus, persisting in one for a further 2 months. Among the 50 patients, total tumor removal was achieved in 47 patients (94%), subtotal in two patients (4%). One patient died intraoperatively due to subarachnoid haemorrhage. CONCLUSION The endoscopic endonasal transsphenoidal approach for removing pituitary lesions is a form of minimally invasive surgery offering excellent postoperative results.

Endoscope-assisted removal of colloid cysts of the third ventricle

Colloid cysts are benign space-occuping lesions, which arise from the velum interpositum or the choroid plexus of the third ventricle and are able to produce symptomatic obstruction of the foramina of Monro with resultant hydrocephalus. In our department, we have operated on colloid cysts routinely in an endoscope-assisted microsurgical manner via a key–hole approach. During a period of 10 years, 28 microsurgical resections of colloid cysts of the third ventricle were performed. Seven patients demonstrated colloid cysts inside the third ventricle with obstruction of the right foramen Monro, two patients demonstrated cysts with obstruction of the left foramen Monro. Twelve patients suffered from cysts inside the third ventricle with obstruction of both foramina Monro and five patients demonstrated cysts lying into the third ventricle without obstruction of the foramina. In 21 patients no preoperative therapy was performed outside. Three patients had received shunt systems before in other hospitals, two patients received aspiration of the cysts under stereotactic conditions and two patients received external ventricular drains. Total removal of the cyst was achieved in all patients (100%). No patient received a second operation, because none had a recurrent cyst. All cysts were removed with the cyst wall. Overall clinical improvement was achieved in a long-standing period between 6 and 83 months in 27 (96%) patients. In one patient (4%) the psychomotor disturbance was unchanged and no patient deteriorated. From the microsurgical point of view, the combination of keyhole surgery under endoscopic visual control using preexisting anatomical windows offers an effective minimally invasive approach.

Technical aids in the diagnosis of brain death: a comparison of SEP, AEP, EEG, TCD and CT angiography.

BACKGROUND The use of technical aids to confirm brain death is a controversial matter. Angiography with the intra-arterial administration of contrast medium is the international gold standard, but it is not allowed in Germany except in cases where it provides a potential mode of treatment. The currently approved tests in Germany are recordings of somatosensory evoked potentials (SSEP), brain perfusion scintigraphy, transcranial Doppler ultrasonography (TCD), and electroencephalography (EEG). CT angiography (CTA), a promising new alternative, is being increasingly used as well. METHODS In a prospective, single-center study that was carried out from 2008 to 2011, 71 consecutive patients in whom brain death was diagnosed on clinical grounds underwent recording of auditory evoked potentials (AEP) and SSEP as well as EEG, TCD and CTA. RESULTS The validity of CTA for the confirmation of brain death was 94%; the validity of the other tests was: 94% for EEG, 92% for TCD, 82% for SSEP, and 2% for AEP. In 61 of the 71 patients (86%), the EEG, TCD and CTA findings all accorded with the clinical diagnosis. The diagnosis of brain death was established beyond doubt in all patients. CONCLUSION In this study, the technical aids yielded discordant results in 14% of cases, necessitating interpretation by an expert examiner. The perfusion tests, in particular, can give false-positive results in patients with large cranial defects, skull fractures, or cerebrospinal fluid drainage. In such cases, electrophysiologic tests or a repeated clinical examination should be performed instead. CTA is a promising, highly reliable new method for demonstrating absent intracranial blood flow. In our view, it should be incorporated into the German guidelines for the diagnosis of brain death.

First clinical results with a new telemetric intracranial pressure-monitoring system.

BACKGROUND: The knowledge of intracranial pressure (ICP) is the basis of an appropriate neurosurgical treatment. Because clinical, fundoscopic, or radiological data alone are often elusive, a pre- or postoperative long-term monitoring of the ICP itself is desirable. OBJECTIVE: We describe the first clinical experiences with a new telemetric ICP-monitoring device. METHODS: The transducer of this telemetric intraparenchymal pressure probe is placed under the galea over the calvaria. ICP can be monitored via a special telemetric reader, placed over the intact skin, and the ICP values are stored in a small portable computer. The system does not require an intensive care environment and can be used in any ward or even at home. The system was successfully applied in 10 patients (age, 3-56 years) in whom raised ICP due to hydrocephalus, shunt dysfunction, endoscopic third ventriculostomy failure, craniostenosis, or pseudotumor cerebri was suspected. RESULTS: Continuous telemetric monitoring of ICP was performed for 2 to 24 weeks. In 7 patients, increased ICP values could be excluded, and further surgical maneuvers were avoided. In 3 patients, repeated plateaus or continuously raised ICP indicated surgery resulting in a normalization of ICP. CONCLUSION: This new telemetric system was safe and effective for ICP measurement over a long period, including home monitoring. For the patients, it was easy to handle, and reliable data could be recorded over many weeks. Based on this preliminary experience, the authors consider the new system extremely advantageous in surgical decision making in particularly difficult cases of suspected abnormalities of ICP.

Detection of intracranial circulatory arrest in brain death using cranial CT-angiography.

Computed tomographic‐angiography (CT‐A) is becoming more accepted in detecting intracranial circulatory arrest in brain death (BD). An international consensus about the use and the parameters of this technique is currently not established. We examined intracranial contrast enhancement in CT‐A after clinically confirmed BD, compared the results with electroencephalography (EEG) and Transcranial Doppler Ultrasonography (TCD) findings and developed a commonly applicable CT‐A protocol.

Effect of intraarterial papaverine or nimodipine on vessel diameter in patients with cerebral vasospasm after subarachnoid hemorrhage

Introduction. Papaverine (P) and nimodipine (N) are the most widely used vasodilators when angiographic and symptomatic vasospasm is present after subarachnoid aneurysmatic hemorrhage (SAH). Their effect is only short-lived and no direct comparisons have been undertaken to evaluate the action of both substances directly. We retrospectively assessed the effect of either P or N on angiographic diameter reduction and capillary blood flow. Methods. Fifteen SAH patients with secured aneurysms and cerebral vasospasm received intraarterial P, fifteen similar patients received N. As the primary endpoint, pre- and post-infusion arterial diameters and capillary blood flow were rated retrospectively on angiographies and compared by RM-ANOVA. Secondary endpoints were the difference in the modified Rankin Scale between the two groups on admission and at discharge, the occurrence of delayed cerebral ischemia, the separate effects on angiographic diameter and capillary blood flow and the overall response rate to the vasodilator infusion. Results. Angiographic resolution of diameter reduction and angiographically assessed capillary blood flow together differed not significantly between both groups. P infusion dilated all angiographic demonstrable vessels while N infusion was ineffective in 16% of the patients. Capillary flow on pre- and post-infusion angiographies was not different between the two groups. Conclusion. P and N seem to differ in the effect on cerebral diameter reduction in patients with vasospasm after SAH. The clinical implications remain to be established. A multimodal approach, perhaps combining different agents for intraarterial infusion in such patients, needs to be evaluated.

Simple endoscopic decompression of cubital tunnel syndrome with the Agee system: anatomic study and first clinical results.

BACKGROUND Simple decompression in ulnar nerve compression syndromes offers options for endoscopic applications. OBJECTIVE The authors present their initial experience with the Agee device. PATIENTS AND METHODS The monoportal endoscopic technique (Agee system) was evaluated on 10 cadaveric arms. Subsequently, 32 arms of 29 patients were operated on between January 2006 and March 2009. All patients presented with typical clinical signs and neurophysiologic studies. Long-term follow-up examinations were obtained in 27 of 32 arms. RESULTS In the cadaver study, the ulnar nerve was always correctly identified. No nerve damage occurred, and sufficient decompression of the ulnar nerve was always achieved. In the clinical series, no intraoperative complications were observed. A change to open technique was not required, and no worsening of the cubital tunnel syndrome occurred. Two wound infections required surgical wound cleaning. Wound hematomas treated conservatively were found in 5 cases. On long-term follow-up, an improvement in the McGowan-Classification was achieved in 22 of 27 cases. One patient was operated on by open surgery after endoscopic surgery. CONCLUSION The endoscopic technique for ulnar nerve entrapment syndrome using an Agee device appears to be safe and efficient. The results are comparable to those achieved with simple open decompression. A randomized prospective study should be performed to further evaluate the value of new technique in ulnar nerve entrapment syndrome.

Computed tomographic angiography as a useful adjunct in the diagnosis of brain death.

BACKGROUND: Because of its widespread accessibly, computed tomographic angiography (CT‐A) is a promising technique in the detection of intracranial circulatory arrest in brain death (BD). Several studies assessed this tool, but neither have standardized evaluation parameters been developed nor has information about specificity become available. METHODS: We conducted a prospective study between January 2008 and April 2012. Thirty patients were admitted to our University Hospital (16 men and 14 women; age, 18–88 years) and underwent CT‐A scanning at two occasions: immediately after the first signs of loss of brain stem reflexes and after definitive determination of brain. The results of CT‐A were compared with transcranial Doppler ultrasonography and electroencephalogram. RESULTS: In 3 of 30 patients, we observed a termination of contrast flow at the level of the skull base and foramen magnum in arterial scanning series before the clinical determination of BD. After the clinical determination of BD, the opacification of all vascular territories in arterial phase scanning was found in one case, but venous phase scanning revealed no blood return in internal cerebral veins. In all other cases, contrast filling ceased at level of skull base or below. The specificity of CT‐A in the detection of intracranial circulatory arrest was 90%, and sensitivity was 97%. CONCLUSION: CT‐A is reliable and appropriate technical investigation to detect intracranial circulatory arrest in BD. The evaluation of contrast enhancement in arterial phase scanning seems to be more reliable than that in venous phase. An international consensus about a uniformly applied CT‐A protocol for the evaluation of BD should be established. LEVEL OF EVIDENCE: Diagnostic study, level V.

Mesencephalic ependymal cysts : treatment under pure endoscopic or endoscope-assisted keyhole conditions

OBJECT Primary intracranial ependymal cysts are extremely rare. Similar to congenital intraparenchymal cysts in the mesencephalon they usually occur with symptoms of an occlusive hydrocephalus or symptoms like Parinaud syndrome, dizziness, or gait disturbance. The objective of this study was to evaluate the surgical methods for the treatment of these cysts and the clinical outcome of the patients. METHODS The authors present the clinical records of 8 patients who were treated in their department for symptomatic mesencephalic ependymal cysts in the past 10 years. The patient age ranged from 22 to 60 years with a mean age of 44 years. In 4 cases the authors performed a suboccipital infratentorial supracerebellar approach by using endoscope-assisted microsurgery. The other 4 patients underwent a pure endoscopic procedure over a frontal bur hole trepanation. RESULTS Four patients became symptom free, and the remaining 4 improved significantly after a mean follow-up duration of 38.5 months (range 5-119 months). One patient underwent 2 operations: first a ventriculocystostomy and 4 months later endoscopic third ventriculostomy because of recurrent hydrocephalus. In 1 case a second surgery was necessary because of a wound infection. In all of the patients an adequate fenestration of the cyst was achieved. CONCLUSIONS A symptomatic mesencephalic ependymal cyst is an indication for neurosurgical intervention. These cysts can be treated successfully and most likely definitively by a pure endoscopic or endoscope-assisted keyhole neurosurgical technique. There were no morbid conditions or death due to the procedures in this group of 8 patients. Therefore, the authors regard these surgical procedures to be good alternatives to treatments such as shunt placement or stereotactic aspiration of the cysts.

CT Angiography as a Confirmatory Test in Brain Death

OBJECTIVE From recent studies, it remains unclear whether CT angiography could be an alternative to other established ancillary tests for the diagnosis of brain death. We examined intracranial contrast enhancement in CT angiography after clinically established brain death and compared the results with EEG and TCD findings. MATERIALS AND METHODS Prospective study between April 2008 and January 2010. EEG, TCD and CT angiography were performed in 40 patients aged between 18 and 88 years (mean 56 years) who fulfilled the clinical criteria of brain death. RESULTS In all cases, the common carotid artery, cervical internal carotid artery, cervical vertebral artery and superficial temporal artery opacified in an arterial CT angiography series. 37 out of 40 cases demonstrated no opacification of both MCA-M4, ACA-A3, PCA-P2 segments, and BA. CONCLUSION CT angiography is a promising method of evaluating intracranial circulatory arrest in brain death with a high spatial and temporal resolution, superior to all other established technical procedures. The examination is easily accessible in most hospitals, operator independent, minimally invasive and inexpensive. Therefore, CT angiography has the potential to enlarge the existing armamentarium of confirmatory brain death tests.