Stereolithography in oral and maxillofacial operation planning.

Stereolithography (STL) is a method of organ-model-production based on computed tomography scans which enables the representation of complex 3-dimensional anatomical structures. Surfaces and internal structures of organs can be produced by polymerization of UV-sensitive liquid resin using a laserbeam. In oral and maxillofacial surgery this technique is advantageous for reconstruction of severe skull defects because a more accurate preoperative planning is possible. Using recently developed software we are able to reconstruct unilateral bony defects by virtual mirror imaging of the contralateral side and production of a STL mirror model as well as the reconstruction of non-mirrorable defects by superposition. Advantages of STL are the representation of complex anatomical structures, high precision and accuracy, and the option to sterilize the models for intraoperative use. More accurate planning using this method improves postoperative results, decreases risks and shortens treatment time.

On the evaluation of cranio-cervical decompression: normalisation of the cerebral spinal fluid circulation in MRI?

1) By means of "cine-MRI" a semi-quantitative analysis of CSF pulsations in the aqueduct of Sylvius can be carried out. 2) This investigation enables a qualitative evaluation of the cranio-spinal CSF flow phenomena. On the one hand this information is a valuable aid for neurosurgeons for diagnosis and on the other, cine-MRI progress controls allow an evaluation of the success of an operation in the sense of a quality control.

[Remission of schizophreniform psychosis after brain tumor surgery]. / Remission einer schizophreniformen Psychose nach Hirntumoroperation.

A 19-year-old female was admitted to hospital due to a schizophrenia-like psychosis of the paranoid type including delusions and various hallucinations. Neurologically she only showed tics of the eyebrows with increased eye blinking. 30 months before an astrocytoma located on the left basal temporal lobe had been resected after the patient suffered from several psychomotor and two grand mal seizures. Following post-operative anticonvulsant therapy seizures had completely disappeared and the patient had been free of symptoms of any kind. After the acute onset of the psychosis another follow-up MRI of the brain using coronary sections revealed a small relapse-tumor. Symptoms disappeared after high-dose neuroleptic therapy. Finally another surgical intervention led to a lasting remission of the psychotic symptomatology (so far 18 months). Postoperatively neuroleptics could be discontinued. Clinical picture and MRI findings will be discussed with a focus on possible etiological factors in schizophrenia.

[Trans-sphenoid gunshot injury of the head. Anatomic viewpoints]. / Die transsphenoidale Kopfschussverletzung. Anatomische Gesichtspunkte.

The transsphenoidal gunshot injury of the head is a subgroup of the temporal gunshot injury, generally with a bad prognosis quoad vitam. Important neural and vascular structures could be damaged by penetration of the missile. In our case the important structures were "missed" exactly and the patient survived without severe neurological deficits. With this case anatomical considerations of the transsphenoidal gunshot injury are made.

Eleven times recurrences of a parasagittal falxmeningioma. Case report.

Although meningiomas are of benign character and generally of encapsulated growth, recurrence is a known problem in treatment. The authors present the time course of a recurrent parasagittal meningioma of the falx, which recurred eleven times. Despite modern radiological diagnostic methods, which made early diagnosis of recurrent tumour possible, and the use of modern microsurgical techniques with radical tumour extirpation and followed by radiotherapy, the fatal course of benign tumour disease could not be stopped.

[Gunshot injuries of the brain caused by air pressure guns]. / Gehirnschussverletzungen durch Luftdruckwaffen.

The article describes the historical and legal basis, as well as the ballistic criteria of injuries caused by air-rifle shots to the head. Six of our own cases of craniocerebral air-gun pellet injuries are discussed and critically assessed, using the results communicated in other papers as the basis of the discussion. The different post-traumatic complications, including the histopathological reaction of the brain to lead-pellets, are considered. The literature is reviewed and the indications for stereotactic removal or craniotomy of intracranial air-gun pellets are discussed. Air rifles, while occasionally the cause of serious head injuries, are rarely thought of as lethal weapons. However, this article illustrates the potential penetrating power of the air-gun pellet, a fact not always appreciated by physicians.