PubMed Health⌕ Search

Biomedical subjects

P Decq

Publications and source records attributed to P Decq.

At least 19 recordsLinked to original sources
PubMed2005

[Endoscopic ventricular anatomy].

Neurosurgical endoscopy enables in situ exploration of the dilated ventricular system, primarily for therapeutic rather than diagnostic purposes. Ventriculocisternostomy in patients with obstructive hydrocephalus is the most widely performed endoscopic procedure. Perfect knowledge of the intraventricular anatomy is necessary for proper endoscopic navigation so the operator always recognizes the position of the endoscope and the anatomic structures encountered. Endoscopic anatomy in this situation is different from normal anatomy because of the hydrocephalus. Anatomic landmarks must be reassessed. We present here this "new" anatomy.

Cerebral Ventricles↗
PubMed2003

Long term course of the H reflex after selective tibial neurotomy.

OBJECTIVES: This study was conducted to evaluate the long term clinical and electrophysiological outcome by recording the H reflex in a consecutive series of six patients treated by selective tibial neurotomy for spastic equinus foot. METHOD: The amplitudes of Hmax reflexes, Mmax responses, and Hmax:Mmax ratio were recorded in six patients with chronic lower limb spasticity, before and after surgery, at day 1 and 8 months and 24 months after selective tibial neurotomy. The passive range of movement, the stretch reflex score according to the Tardieu scale, the osteoarticular and tendon repercussions, and the quality of motor control of dorsiflexion were evaluated preoperatively and postoperatively. RESULTS: At the end of the study, all patients presented a reduction of equines. Gait and Tardieu's score of spasticity had improved in all patients. Active dorsiflexion of the ankle was unchanged in four patients, but two improved by 5 degrees to 12 degrees. In five cases, fascicular resection of the superior nerve to soleus was, alone, sufficient to reduce spastic equinus foot, without recurrence, for a mean follow up of 28 months. Two patients were reoperated on, one for remaining spasticity related to an underestimated spasticity of the gastrocnemius muscles, and the other for painful claw toes. Hmax, Mmax, and Hmax:Mmax ratios were significantly lower the day after surgery. The reduction of Hmax and Hmax/Mmax ratio remained stable over time and was still statistically significant two years after the operation. However, the value of Mmax eight months postoperatively was no longer significantly different from the preoperative value. CONCLUSION: This study shows the long term efficacy of the selective tibial neurotomy as treatment of spastic equinus foot. Neurotomy confined to fibres supplying the soleus muscle is sufficient in most cases and acts by decreasing sensory afferents without significant long term motor denervation.

Adolescent↗
PubMed2003

[Pathophysiology of spasticity].

Lance's definition of spasticity focuses on the exaggeration of the tonic stretch reflex as one component of the upper motor neuron syndrome. In daily practice, many different symptoms are referred to as spasticity. Experimental studies stress the particular role of the premotor cortex and the medial reticular formation for the genesis of spasticity. Physiological studies clearly demonstrate the two components, phasic and tonic, of the stretch reflex. Whatever the pathology, the clinical picture of spasticity seems to depend less upon the etiology of the lesion and more upon its location in the neuraxis. There is a regional organisation of the spinal circuitry according to the function of the segmental nerves and, therefore, a particular clinical presentation related to each spinal segment. The muscular efferents are also heterogeneous and linked to function. This is the fundamental base of focal treatment of spasticity.

Animals↗
PubMed2003

[Interest of anesthetic blocks for assessment of the spastic patient. A series of 815 motor blocks].

BACKGROUND: The purpose of the study was to emphasize the value of anesthetic blocks in the approach to the spastic patient. The report relates our experience concerning 566 patients (ranging in age from 4 to 72 years, mean 48 years) tested by 815 motor blocks performed within a "spasticity and dystonia evaluation" unit. The spasticity was mainly due to stroke (56%), cerebral palsy (21%) and traumatic brain injury (14%). METHODS: Motor blocks were performed with standardized procedure (specific needle, neurostimulator, localization technique), analytic and functional assessment. RESULTS: The anesthetic was mostly 1% non-adrenalized etidocaine, chosen for its onset and duration of action. Re-injections were few and side effects exceptional. Quality and motor blocks results were technique-dependent and required patient cooperation. The spasticity disappeared in blocked muscles. Tardieu and Ashworth modified scale showed constantly decreased spasticity (2 to 3 points) with better sensitivity for the Tardieu modified score. Local anesthetic blocks determined the relative contributions of overactivity and of muscle shortening in the generation of the pathologic posture, the muscle or muscles responsible for the spastic pattern and the level of active performance of the antagonistic muscle. New stability was evaluated by functional assessment of gait posture and prehension. CONCLUSION: At the present time, anesthetic motor blocks represent a necessary and decisive stage procedure as regards spastic patient assessment. This method is particularly useful to anticipate a new functional balance and simulate treatment. Motor blocks provide acute knowledge of the pathological pattern and a better adjustment of therapeutic directions.

Adolescent↗
PubMed2003

[Peripheral neurotomies for the treatment of focal spasticity of the limbs].

Introduced by Stoffel in 1912 for the treatment of spastic equinus foot, selective fascicular neurotomy consists in a partial section of the motor collaterals of the muscles presenting excessive spasticity. This peripheral surgery for spasticity is based on two main concepts: 1) Spinal reflexes and muscles are heterogeneous and have a regional organization depending on their role during normal movements. This is the physiological base of focal spasticity and peripheral treatment. 2) There is a differential re-innervation after a partial section, leading to motor recovery without spindles reinnervation (therefore without spasticity). Before performing neurotomies, a careful clinical assessment is required: what kind of spasticity? For what kind of goal (functional or comfort)? The surgery effects can be mimicked by motor nerve blocks (anesthetic drugs) to give to the patient an idea of the expected result. There are many neurotomies, depending on the clinical status, either in the lower or the upper limb. The most frequent is tibial neurotomy for spastic equinus foot.

History, 20th Century↗
PubMed2003

[Indications of neurosurgical procedures for spasticity].

Neurosurgery for spasticity requires perfect knowledge of all the mechanisms involved in the control of movement. Spasticity should be clearly checked in all these aspects: phasic, tonic and flexor reflexes. Its contribution to the patient's handicap should be assessed. Motor block or intrathecal injections of baclofen are useful tests to evaluate the surgical indications for well defined goal and understood by the patient himself. The choice of the procedure depends on the patient and the type of spasticity. Post-operative assessment is very important to improve the surgical procedures in the future, going towards motor restoration.

Humans↗
PubMed2001

Resumption of luteinizing hormone pulsatility and hypogonadotropic hypogonadism after endoscopic ventriculocisternostomy in a hydrocephalic patient.

OBJECTIVE: To study gonadotropin pulsatility before and after surgical cure of hydrocephalus. DESIGN: Case report. SETTING: Department of Endocrinology and Centre d'Investigations Cliniques, Necker Hospital, Paris, France. PATIENT(S): A 29-year-old woman who presented with secondary amenorrhea. INTERVENTION(S): The patient underwent an endoscopic ventriculocisternostomy that led to restoration of normal menses and resolution of hypogonadism. MAIN OUTCOME MEASURE(S): A gonadotropin pulse study was performed before and 2 and 5 months after surgery. RESULT(S): No LH pulse was observed before surgery. Emergence of pulsatility was observed 2 months after surgery, and pulses became clearly individualized after 5 months. CONCLUSION(S): This observation strongly suggests that amenorrhea, in case of chronic hydrocephalus, is indeed due to a hypothalamic dysfunction of the GnRH pulse generator.

Adult↗
PubMed2001

Effects of propofol on H-reflex in humans.

BACKGROUND: Depression of spinal cord motoneuron excitability has been proposed to contribute to surgical immobility. The H-reflex, which measures alpha-motoneuron excitability, is depressed by volatile anesthetics, whereas the action of propofol is unknown. The objective of this study was to determine the effects of propofol anesthesia on the H-reflex. METHODS: In 13 patients (group 1), H-reflex was measured before (T0), 3 min after (T1), and 10 min after (T2) a 2-mg/kg bolus dose of propofol, followed by an infusion of 10 mg x kg(-1) x h(-1). Ten patients (group 2) were studied when propofol was given via a programmable pump set to a propofol blood concentration of 6 microg/ml, and 10 patients (group 3) were studied with the pump set to 9 microg/ml. Latencies and amplitudes of H-reflexes (H0, H1, H2) and M-responses (M0, M1, M2) of the soleus muscle were recorded, and H/M ratios (H0/M0, H1/M1, H2/M2) were calculated. RESULTS: In group 1, H-reflex amplitudes and the H/M ratio were diminished after induction with propofol (H0 vs. H1, P = 0.033; H0/M0 vs. H1/M1, P = 0.042). After 10 min of propofol infusion, the H2/M2 ratio was still decreased versus H0/M0 (P = 0.031). In group 2, no difference was detected. In group 3, propofol depressed H-reflex amplitudes at T2 (H0 vs. H2, P < 0.01), and amplitudes were also lower at T2 than at T1 (H1 vs. H2, P < 0.01). In this group, the H/M ratio decreased from T0 to T2 (H0/M0 vs. H2/M2, P < 0.002). CONCLUSIONS: During steady state conditions using propofol as the sole agent, a depression of the H-reflex is observed only at a high blood concentration of 9 microg/ml. The authors suggest that immobility during propofol anesthesia is not caused by a depression of spinal motoneuron circuit excitability.

Anesthesia, Inhalation↗
PubMed2001

Chiari I malformation: a rare cause of noncommunicating hydrocephalus treated by third ventriculostomy.

OBJECT: Hydrocephalus associated with Chiari I malformation is a rare entity related to an obstruction in the flow of cerebrospinal fluid (CSF) in the foramen of Magendie. Like all forms of noncommunicating hydrocephalus. it can be treated by endoscopic third ventriculostomy (ETV). The object of this study is to report a series of five cases of hydrocephalus associated with Chiari I malformation and to evaluate the use of ETV in the treatment of this anomaly. METHODS: Five patients (four women and one man with a mean age of 29.6 years) underwent ETV for hydrocephalus associated with Chiari I malformation between April 1991 and February 1997. All patients had presented with paroxysmal headaches, which in two cases were associated with visual disorders. All patients had also presented with hydrocephalus (mean transverse diameter of the third ventricle 12.79 mm; mean sagittal diameter of the fourth ventricle 18.27 mm) with a mean herniation of the cerebellar tonsils at 13.75 mm below the basion-opisthion line. Surgery was performed in all patients by using a rigid endoscope. No complications occurred either during or after the procedure, except in one patient who experienced a wound infection that was treated by antibiotic medications. The mean duration of follow up in this study was 50.39 months. Four patients became completely asymptomatic and remained stable throughout the follow-up period. One patient required an additional third ventriculostomy after I year, due to secondary closure, and has remained stable since that time. Postoperative magnetic resonance images demonstrated a significant reduction in the extent of hydrocephalus in all patients (mean transverse diameter of the third ventricle 6.9 mm [p = 0.0035]; mean sagittal diameter of the fourth ventricle 10.32 mm [p = 0.007]), with a mean ascent of the cerebellar tonsils from 13.75 mm below the basion-opisthion line to 7.76 mm below it (p = 0.01). In addition, CSF flow was identified on either side of the orifice of the third ventriculostomy in all patients postoperatively. CONCLUSIONS: Results in this series confirm the efficacy of ETV in the treatment of hydrocephalus associated with Chiari I malformation. It is a reliable, minimally invasive technique that also provides a better understanding of the pathophysiology of this malformation.

Adult↗
PubMed2000

Soleus neurotomy for treatment of the spastic equinus foot. Groupe d'Evaluation et de Traitement de la Spasticité et de la Dystonie.

OBJECTIVE: This prospective, nonrandomized, noncontrolled study was performed to evaluate the results of a new type of neurotomy, namely the soleus neurotomy, for treatment of the spastic equinus foot. METHODS: Between May 1996 and March 1998, 46 patients were treated for a spastic equinus foot. Clinical status, spasticity (Ashworth Scale score), and kinematic parameters of the gait were determined before and after surgery. The neurotomy was performed on the upper nerve of the soleus in all cases and was associated with other neurotomies (lower nerve of the soleus, 21 patients; gastrocnemius, 9 patients, tibialis posterior, 18 patients; flexor hallucis longus, 16 patients; and flexor digitorum longus, 17 patients). RESULTS: The mean follow-up period was 15 months (range, 8-28 mo). The equinus deformity disappeared clinically in all patients. Before the operation, all patients had an Ashworth Scale score of 2, with an inexhaustible clonus present on knee extension and persisting with knee flexion (Tardieu Scale score, 4), which was abolished in 95% of the patients after surgery. Two patients still had some clonus on knee extension; this did not interfere with their clinical improvement. Knee recurvatum disappeared in eight patients. Analysis of kinematic parameters demonstrated a statistically significant increase in joint motion of the second rocker (P = 0.0026) of the ankle during stance. The duration of the stance or swing phase, length of the walking cycle, and velocity or rate of spontaneous walking were not significantly modified. CONCLUSION: The study demonstrated that soleus neurotomy is effective for the treatment of spastic equinus foot, leading to abolition of spasticity and improvement in the range of ankle motion during the stance phase of gait.

Adolescent↗
PubMed2000

A new device for endoscopic third ventriculostomy.

Since its description by Dandy in 1922, several techniques have been used to perform third ventriculostomy under endoscopic control. Except for the blunt technique, in which the endoscope is used by itself to create the opening in the floor of the third ventricle, the other techniques require more than one instrument to perforate the floor of the ventricle and enlarge the ventriculostomy. The new device described is a sterilizable modified forceps that allows both the opening of the floor and the enlargement of the ventriculostomy in a simple and effective way. The new device has the following characteristics: 1) the tip of the forceps is thin enough to allow the easy perforation of the floor of the ventricle; 2) the inner surface of the jaws is smooth to avoid catching vessels of the basal cistern; and 3) the outer surface of the jaws has indentations that catch the edges of the opening to prevent them from slipping along the instrument's jaws. The ventricle floor is opened by gentle pressure of the forceps, which is slowly opened so that the edges of the aperture are caught by the distal outer indentation of the jaws, leading to an approximately 4-mm opening of the floor. This device has been used successfully in 10 consecutive patients. This new device allows surgeons to perform third ventriculostomy under endoscopic control in a very simple, quick, and effective way, avoiding the need for additional single-use instruments.

Endoscopes↗
PubMed2000

Colloid cysts of the third ventricle: are MR imaging patterns predictive of difficulty with percutaneous treatment?

BACKGROUND AND PURPOSE: Colloid cysts of the third ventricle are rare benign brain tumors. The purpose of this study was to correlate their patterns on MR images with the probability of success of percutaneous treatment. METHODS: Nineteen patients underwent endoscopic treatment for colloid cysts of the third ventricle. The cases were divided into two groups based on difficulty of the aspiration procedure. We reviewed CT scans and MR images and divided cysts into groups based on their signal intensity on the MR images and their density on CT scans. Intensity and density were correlated with difficulty of aspiration during the endoscopic procedure. RESULTS: The aspiration procedure was difficult in 63% of the cases. Eighty-nine percent of hyperdense cysts on unenhanced axial CT scans were categorized as difficult, and 75% of hypodense cysts were categorized as easy. On T2-weighted MR sequences, 100% of low-signal cyst contents were difficult and nearly 63% of high-signal lesions were easy. There was a significant correlation between the T2-weighted sequences and the CT scans regarding the difficulty of the aspiration procedure. CONCLUSION: T2-weighted MR sequences are useful for predicting difficulty of aspiration during stereotactic or endoscopic procedures. A T2-weighted low-signal cyst is correlated with high-viscosity intracystic contents.

Adult↗
PubMed2000

[Endoscopic anatomy of the third ventricle].

According to the development of neurosurgical endoscopy (and especially for third ventriculostomy), the endoscopic anatomy in hydrocephalus should be well known and utilized for orientation. The endoscopic pictures are obtained with a 30; telescope, acquired by a digitalized camera and visualized on a video monitor. The pictures are then numerized on a DKR system. Endoscopic anatomy of the third ventricle is described with a particular focus on the anatomical landmarks and their variations around the foramen of Monro, the anterior and posterior walls of the third ventricle. The knowledge of this anatomy is essential for the safety and the reliability of intraventricular endoscopic procedures.

Endoscopy↗
PubMed2000

[Endoscopic surgery of third ventricle lesions].

The endoscopic approach of the tumors of the third ventricle interests mainly the colloid cysts but also offers the possibilities of biopsies. Twenty two patients (16 men and 6 women, average age 41 years) presenting with hydrocephalus related to a tumor of the pineal area were treated by a ventriculostomy with attempt at biopsy : they are outside of the limits of this report. Twenty two other patients (15 men, 7 women, average age 39 years) were operated on from 1994 to 1999 for a colloid cyst, and 2 of them were admitted in emergency in sudden coma. The CT scan showed a colloid cyst (hyperdense in 16 patients) associated with an hydrocephalus, except for a patient previously shunted. The diameter of the cyst varied from 4 to 50 mm (average of 20 mm). All the patients were operated on using a rigid endoscope. Among the 20 patients presenting a tumor of the pineal area, a biopsy was possible only in 4 cases (20%). There were no hemorrhage nor neurological disorders. In all the cases, the size and the number of the specimens were sufficient to allow the histological diagnosis. For the patients presenting with colloid cyst, the average follow-up is 2 years. All the preoperative symptoms disappeared except for the memory disorders which were improved. The post-operative Evans index decreased significantly. No residual cyst was observed on the post-operative MRI in 14 patients (63%). Among these patients, an asymptomatic recurrence was observed and remained stable after 44 months of follow-up. A residual cyst was observed in 8 patients (36%), with a diameter from 5 to 25 mm (average 9 mm). No patient required a shunt procedure, and no patient presented hemorrhagic complication. Endoscopy is especially useful in the first line treatment of the colloid cysts of the third ventricle.

Adult↗
PubMed1999

Intracranial dural arteriovenous fistulae with perimedullary venous drainage. Anatomical, clinical and therapeutic considerations.

We report five cases of intracranial dural arteriovenous fistula (DAVF) with perimedullary venous drainage. All the patients presented with rapidly progressive myelopathy and three had autonomic disorders. The DAVF were on the tentorium cerebelli (two cases), sigmoid (one), superior petrosal (one), and cavernous sinus (one). Slow venous drainage was directed through dilated perimedullary cervical veins. The transverse sinus was occluded in two cases. MRI, performed in four cases, demonstrated high signal on T2-weighted spin-echo sequences in the medulla oblongata and upper cervical spinal cord consistent with oedema, which signal resolved after complete cure of the DAVF in three cases. Embolisation was performed in all cases. It was followed by clinical deterioration in two cases and in the dramatic improvement in the other three, with complete clinical cure in two. Extensive venous thrombosis may explain the deterioration observed in one case.

Adult↗
PubMed1998

Endoscopic management of colloid cysts.

OBJECTIVE: Several surgical approaches have been proposed for the treatment of colloid cysts, which still remains controversial. The most recent technique used is endoscopy. By its nature, endoscopy cannot offer complete removal, as compared to microsurgical techniques, but can do more than puncture. To evaluate the usefulness of endoscopy for colloid cyst surgery, a series of 15 patients who were operated on for colloid cysts under endoscopic control since 1994 was reviewed. METHODS: The presenting symptoms of our patients (10 men and 5 women) were intermittent headache (10 patients), nausea (3 patients), short-term memory loss (4 patients), coma (2 patients), gait disturbance (3 patients), blurred vision (2 patients), and mental status changes (3 patients). The sizes of the cysts ranged from 4 to 50 mm (median, 22.93 mm). Depending on the radiological appearance, the procedure was performed via a right (10 patients) or left (5 patients) precoronal burr hole. A rigid neuroendoscope was used. Initial stereotactic placement of the neuroendoscope was used in two patients who had moderate hydrocephalus. In the other patients, hand-guided endoscopy was performed using an articulated arm. The cysts were perforated with a needle. The opening was enlarged with microscissors. The cyst material was aspirated, and the remaining capsule was coagulated. RESULTS: The average follow-up was 15.26 months (range, 1-28 mo). Total aspiration of the cysts was achieved in 12 patients, as revealed by normal postoperative magnetic resonance imaging. Control magnetic resonance imaging revealed residual cysts in three patients. One patient presented with an asymptomatic recurrence at 1 year. Resolution of the symptoms was obtained in all patients except for two of the four patients with preoperative memory deficit (improvement without complete recovery). There was no mortality or morbidity. CONCLUSION: These results show that endoscopy is a safe and promising percutaneous technique for the treatment of colloid cysts of the third ventricle. Longer follow-up is, however, still required.

Adult↗