Stereotactic management of craniopharyngiomas

The authors present a series of 47 patients with craniopharyngiomas treated by stereotaxy in the past 15 years. There was no mortality nor immediate postoperative morbidity in the treatment of the cystic portion of the neoplasm. Intracavitary colloidal yttrium (90Y) was extremely effective in obtaining long-lasting disappearance of craniopharyngioma cysts. In children, yttrium worsened panhypopituitarism, while it was well tolerated by teenagers and adults. Craniopharyngiomas are often mixed (solid-cystic) and the majority of cases have a predominant cystic portion, where stereotaxy is a valid alternative to open surgery, which presents a high morbidity and mortality.

Surgical management of cavernous angiomas in children

Cavernous angiomas are vascular malformations affecting any part of the central nervous system (CNS). The management of asymptomatic cavernous angiomas is still debated due to their poorly understood natural history, although more data are now available regarding results of surgical treatment in symptomatic cases. The authors report their surgical experience with 18 pediatric patients operated on for symptomatic CNS cavernous angiomas. The children ranged in age from 10 months to 17 years, without a relevant sex difference. Cavernous angiomas were intracranial in 17 cases: 15 being in the supratentorial compartments and two in the cerebellum. Clinical manifestations were as follows: seizures in 11 cases, focal neurologic deficits in five, and headache in one. The 18th case was observed in a girl showing paraparesis in the spinal subdural-extramedullary space at T8-T9 level. Excision of four deep cerebral lesions was performed after stereotactic localization through non-eloquent cortex. Pathologic confirmation of cavernous angiomas was obtained in all patients. Mortality from surgical procedures was absent in this series. The follow-up period ranged from 1 to 16 years. All 11 epileptic patients obtained seizure control; improvement or stabilization of neurologic symptoms was observed in the remaining seven patients.

[Interstitial laser coagulation of benign prostatic hyperplasia]

We report on the new method of interstitial laser coagulation for the treatment of benign prostatic hyperplasia (BPH). The procedure is based on the interstitial application of Nd:YAG laser irradiation, delivered through a new light guide system. Such light applicators coagulate constant tissue volumes in a homogeneous manner, as proven by in vitro studies in different tissues, including surgically removed prostate adenoma. The extent of the coagulation is determined by laser power and irradiation time. At 5 W, for example, and during a 10-min period, this zone reached a diameter of up to 20 mm. Temperatures generated in the process were over 100 degrees C, as measured by time/space resolution. These results were confirmed by in vivo studies in canine prostates. In the course of 7 weeks, the coagulated areas formed scars with degeneration and fibrosis, accompanied by marked shrinking. Neighbouring organs were not affected. The method was successfully transferred to clinical practice. The application of the light guides to the lateral lobes was performed percutaneously from the perineum under transrectal ultrasound guidance. The median lobe was punctured transurethrally under direct vision. Twenty-seven patients with an average age of 67.7 years were treated between July 1991 and March 1992. At the time of evaluation 15 patients had a follow-up of more than 2 months. They experienced a mean increase of peak flow rate from 6.6 to 15.2 ml/s and a mean decrease of residual volume from 206 to 38 ml. This was accompanied by a marked lessening of symptoms. The average prostate weight decreased from 63 to 44 g. Sexually active patients did not experience retrograde ejaculation.(ABSTRACT TRUNCATED AT 250 WORDS)

Primary intrasellar germinoma: case report

Intracranial germinomas arising primarily within the sella turcica are extremely rare. Preoperative diagnosis is difficult to establish even with sophisticated procedures. Diabetes insipidus is the main clinical manifestation. The authors report a case of an apparently primary intrasellar germinoma causing subclinical pituitary apoplexy in a 12-year-old boy. The transsphenoidal approach and appropriate radiotherapeutic management were employed with a good outcome.

Surgical voice rehabilitation after laryngopharyngectomy. Functional results of tracheo-hypopharyngeal shunts by jejunal transplantation

For surgical voice rehabilitation after pharyngolaryngectomy we use the technique of placing a siphonlike jejunal interposition in order to create a tracheohypopharyngeal shunt. In this paper we present the functional benefits of this method of voice rehabilitation. The best results achieved are compared with a normal voice using the following test parameters: electroacoustic sound analyses and voice status. The findings show that the siphon voice is adequate for everyday purposes and can achieve useful social verbal communication.

Application systems for intracorporeal laser-induced shockwave lithotripsy using the Nd:YAG Q-switched laser

For laser-induced shockwave lithotripsy, the electromagnetic energy of a laser light pulse is converted intracorporeally into the acoustic energy of a shockwave. The lithotriptor is based on a specially developed, Q-switched Nd:YAG laser whose high power light pulses (70 mJ, 25 nsec) are coupled into a flexible quartz fiber with a core diameter of 600 mum. Using focusing elements, energy densities higher than 6 x 10 5 J m -2 can be achieved, resulting in an optical breakdown in water followed by a shockwave. As a result of different absorption mechanisms, the breakdown threshold can be decreased by placing a metallic target into the laser beam. The different shockwave formations of such optomechanical transducers have been measured. First clinical applications have been performed.

Availability of infective larvae of parasitic nematodes of sheep grazing on Kikuyu (Pennisetum clandestinum) pastures in the winter rainfall area

Thirteen groups of 4 South African mutton Merinos grazed for 4 weeks with the flock on Kikuyu pastures and were slaughtered for total and differential worm counts at necropsy. Subsequently 12 groups of 8 week tracers grazed on the pastures and were killed for worm counts post mortem. The following were present in most sheep: Teladorsagia (syn. Ostertagia) circumcincta, Trichostrongylus axei, Trichostrongylus colubriformis, Dictyocaulus filaria and Oesophagostomum venulosum. Haemonchus contortus, Nematodirus spathiger and Trichuris skrjabini were less frequently recovered. Optimal conditions for infestation of grazing sheep occurred from June (late autumn)--October (spring) when mean temperatures in any 4 week period were less than 20 degrees C and a total of greater than 40 mm of rain fell on 8 or more separate days. When the mean temperatures exceeded 20 degrees C pastures were safe, sheep acquiring less than 1,000 worms in 4 weeks.

Paretic neurosyphilis and cerebral gumma. Case report

A rare case of neurosyphilis presenting with dementia paralytica and radiological appearance of cerebral gumma is reported. In accordance with previous comparable reports Authors noticed that diagnosis of this disease actually is still based on serological tests and clinical examination. CT, NMR and Cerebral angiography were not able to provide diagnostic findings, although NMR confirmed its ability to detect lesions not discovered by CT scan. Also findings from stereotactic biopsy only revealed an old not active infection.

Percutaneous surgical treatment of trigeminal neuralgia

The authors report on indications and results of percutaneous surgical treatment of trigeminal neuralgia based on own experiences in 1124 cases. In 912 cases percutaneous thermorhizotomy and in 212 cases percutaneous microcompression have been used. As a conclusion the following considerations have been stressed: I) In both methods slight hypaesthesia appears to obtain good pain relief; II) Percutaneous thermorhizotomy is indicated in third division neuralgias; III) Percutaneous microcompression is indicated for first and second division neuralgias only when the trigeminal cistern is not abnormally dilated; IV) Undesirable side-effects after either thermorhizotomy and microcompression are similar and transitory in most cases; V) Pain recurrence for both procedures are comparable and range at about 25%.

Histochemical and ultrastructural study of the human pineal gland in the course of aging

A histochemical and ultrastructural study was carried out on the pineal gland of 2 day- to 86-year-old subjects. Specimens were obtained by stereotaxis in the course of neurosurgery; other specimens were autoptical pineal fragments. Histochemical and ultrastructural analyses showed lipofuscin pigments, frequently localized in the proximity of blood capillaries and of cytoplasmic microacervuli. The brain sand amount does not appear to be age-related because microacervuli are barely present or frequently absent in the oldest subjects. Its involvement in the secretory activity rather than in gland atrophy is also suggested. The close relationship between cytoplasmic microacervuli and intermediate filaments suggests a possible role of the cytoskeleton in the formation of the brain sand.

Stereotactic mesencephalic tractotomy in the treatment of chronic cancer pain

A report is given on indications and results of treatment of chronic cancer pain using stereotactic mesencephalic tractotomy (SMT), based on own experiences in 202 patients. Percutaneous cervical cordotomy for upper body pain syndromes has been abandoned and replaced by SMT. Operative mortality of SMT was less than 0.5%, and also its morbidity was low and usually transitory. Bilateral procedures may be performed with an interval of at least seven days. Early recurrences within one month (15%) are due to insufficient coagulation. Late pain recurrence occurred in 4% and may be due to either nervous system regeneration (sprouting) or transmission of pain by alternate secondary pathways.

Stereotactic radioisotope implantations in the treatment of inoperable low malignancy neoplasms

The authors report their experience of 53 patients with low grade malignancy cerebral neoplasms treated by means of stereotactic 125-I permanent interstitial radiotherapy. The method has been employed from 1981 to date. The authors confirm the validity of the technique in this brief report, and stress the greater efficacy of this treatment in young patients (less than 40 y/o) than in adults.

Stereotactic biopsy and treatment of brain stem lesions: combined study of 33 cases (Bologna-Marseille)

Intraaxial brain stem tumours are rarely treated by open surgical technique. In Bologna and Marseille, 23 and 10 stereotactic biopsies respectively were performed in patients with brain stem mass lesions. The mortality due to biopsy was 3% (1 pat.); while the morbidity was temporary in 6 cases (18%) and permanent in one patient (3%). The approach to the brain stem was via a frontal burr hole. 7 times, after biopsy and histological diagnosis, radioisotope implant of the neoplasm was performed with 125I (iodine). From the histological diagnoses of the lesions the following was found: only 40% of the young patients had highly malignant tumours; 83% of the adults had neoplasms (not all of the malignant type), while 17% of the verified lesions were non-neoplastic. Since a diagnosis of the lesion nature is impossible with current neuroradiological means, the authors noting a variety of masses found in their experience, emphasize the importance of stereotactic biopsy, as a scarcely invasive method to give a precise diagnosis and a possible treatment.

[First laser irradiation of a bile duct carcinoma under endoscopic control]

For the first time a hepatic-duct carcinoma was treated palliatively with percutaneous endoscopic Neodym-YAG laser irradiation. This enlarged the lumen of the bile duct encased by tumour. The method can be combined with prosthetic as well as radiotherapeutic procedures. The equipment consists of an ordinary choledochoscope and a laser apparatus. The choledochoscope merely needs minimal technical modification of the outer valve of its working channel. Biopsies under endoscopic control make it possible to obtain tissue samples adequate for histological examination before treatment is begun.

Late recurrence of bleeding in a chronic extradural hematoma

Recurrence of bleeding from the inner capsule occurred in a chronic extradural haematoma in a 15-year-old boy 4 months after the original trauma. The case is presented to emphasize the potential hazards of nonsurgical treatment of chronic extradural hematomas.

Parasites in sheep grazing on Kikuyu (Pennisetum clandestinum) pastures in the winter rainfall region

Regular worm counts were done post-mortem on sheep that had grazed on Kikuyu pastures at the Elsenburg Research Station near Stellenbosch, a winter rainfall region. Major species were Trichostrongylus colubriformis, Trichostrongylus axei, while Ostertagia circumcincta was usually present in large numbers. Minor species were Haemonchus contortus, Nematodirus spathiger, Dictyocaulus filaria, Oesophagostomum venulosum, Trichuris spp., Chabertia ovina and larvae of the arthropod Oestrus ovis. Muellerius capillaris caused the formation of nodules in the lungs but were not counted. The trial started in April 1982 and was concluded in March 1984. One hundred and four sheep died or were slaughtered and 99 were examined post-mortem during this period. Total worm burdens rose to a peak of 88,763 (range 67,281-124,735) worms in March 1983, i.e. sheep mortality was such that the flock had to be treated with an anthelmintic in April 1983 to prevent further losses. Kikuyu pastures provide shade, form an excellent mat, the humus layer under the grass retains moisture and is an excellent incubator for preinfective larvae and a protector for infective larvae. If these qualities are combined with more than 100 mm of rain in spring and summer, Kikuyu pastures are a paradise for the free-living stages.

Comparative investigations of the effects of the neodymium:YAG laser at 1.06 microns and 1.32 microns on tissue

The beneficial deep homogeneous coagulation of neodymium (Nd):YAG laser radiation at 1.06 microns owing to low absorption and high scattering in tissue has been documented widely. For another Nd:YAG laser wavelength at 1.32 microns the absorption coefficient of water and saline is approximately ten times higher than at 1.06 microns. This results in more efficient energy conversion into heat in tissue at 1.32 microns. The extinction coefficient in blood at 1.32 microns is only one-third of that at 1.06 microns. We would expect this to result in less heat dissipation by blood and deeper penetration in tissue at 1.32 microns. Nevertheless, at this wavelength scattering also contributes to an effective, uniform distribution of the laser light in the tissue. Animal experiments have been done to examine the effect of wavelength, irradiation time, and beam geometry on tissue damage and to assess its possible clinical uses. The results imply that the 1.32 microns wavelength will produce further indications for the use of the Nd:YAG laser in surgery.

Late considerations in the treatment of low-grade malignancy cerebral tumors with iodine-125 brachytherapy

The authors report their series of 45 patients harboring inoperable, low-grade cerebral neoplasms, treated in the past 6 years with 125I stereotactic brachytherapy. The majority of these tumors were grade I and II astrocytomas and oligodendrogliomas (82.2%). A 2.6- to 6-year follow-up shows good results in 65.6% with reduction or disappearance of the lesions on CT images and good social reentry. Nine patients (23.7%) died prior to follow-up. Young patients (less than 40 years) responded well to interstitial radiotherapy, while patients over 40 with the same histological findings of low-grade tumors responded poorly to this type of treatment. Diffuse infiltrating cortico-subcortical tumors, optochiasmatic gliomas, hypothalamic and lower brainstem neoplasms do not respond satisfactorily to 125I radioisotope implantations.

Stereotactic surgery in the management of deep intracranial lesions in infants and adolescents

Over a period of 5 years, 34 pediatric patients underwent stereotactic surgery for deep-seated brain lesions: 32 patients proved to have a brain tumor, and in 2 cases the lesion was not tumoral; 15 patients with low-grade astrocytomas were treated with 125I interstitial radiotherapy. The importance of stereotactic surgery is emphasized because of its relative safeness, diagnostic reliability, and the possibility of eventual brachytherapy.