Does spasticity result from hyperactive stretch reflexes? Preliminary findings from a stretch reflex characterization study.

PURPOSE: To characterize the stretch reflex response of the biceps brachii in stroke patients with elbow spasticity (prior to or within 15 min of treatment with botulinum toxin) and non-impaired volunteers with the aim of quantifying the stretch reflex excitability and observe the differences between the groups. METHODS: A cross-sectional study. Stretch reflexes from the biceps brachii were elicited following a controlled elbow extension. The amplitude, latency, rise time and duration, calculated from surface EMG recordings from the biceps brachii, were used to characterize the stretch reflex response. RESULTS: Seventeen non-impaired and 14 stroke patients participated. The amplitude was significantly lower in stroke patients than in non-impaired volunteers (p<0.05). The latency was significantly shorter in stroke patients than in non-impaired volunteers (p<0.05). There were no significant differences in rise time or duration (p>0.10). DISCUSSION: Reduction in the amplitude in stroke patients was unexpected suggesting the stretch reflex is not necessarily hyper-excitable in people with clinically diagnosed spasticity. Latency differences suggest decreased presynaptic inhibition and/or increased motor neurone excitability can occur following a stroke. However, carry over effects from previous botulinum toxin treatment may have confounded amplitude measurements. Further work evaluating the excitability of the stretch reflex independent of Botulinum toxin and its contribution to resistance to passive stretching is being conducted.

Bilateral anterior cingulotomy for chronic noncancer pain.

OBJECTIVE: To document the value of bilateral anterior cingulotomy for patients with intractable chronic noncancer pain. METHODS: Twenty-three patients who underwent 28 cingulotomies between 1979 and 1996 for chronic refractory pain were sent questionnaires regarding their subjective response to the surgery and its impact on their pain. Questions dealt with pre- and postoperative pain, ability to resume work or usual activity, medications, family and social interactions, and overall benefit of cingulotomy. Results were compared with long-term (average, 8 yr) clinical follow-up. In 13 patients, pain was predominantly caused by lumbar adhesive arachnoiditis or "failed back." The remainder had venous occlusive disease, ischemic bilateral leg pain, phantom leg pain, postoperative neck pain, or atypical facial pain. RESULTS: Eighteen patients returned questionnaires; two patients died of unrelated causes. Seventy-two percent of patients reported improvement in their pain, 55% were no longer taking narcotics, 67% noted improvement in their family life, and 72% noted improvement in their social interactions. Fifty-six percent of patients reported that the cingulotomy was beneficial, and 28% returned to their usual activities or work. Thirty-nine percent of patients developed transient or well-controlled seizures. Five patients required a second cingulotomy, and one patient did well despite developing brain abscesses. Patient assessments corresponded closely with clinical assessments. CONCLUSION: Bilateral anterior cingulotomy is safe for patients with refractory chronic pain. Seizures reported in this series were well controlled with medication. More than half of all respondents thought they had a positive outcome and that cingulotomy was beneficial to them. There were no deaths related to the procedure.

Right-angle partially compressible hemostatic clip applier.

A modification of a hemostatic clip applier is described that can apply clips at right angles to the plane of the handles. This device may be particularly useful in certain neurosurgical settings where use of the conventional clip applier is difficult. This device also prevents overcompression of clips.

Saline microbubbles monitoring sonography-assisted abscess drainage.

The objective of this study was to assess the use of saline microbubbles as a sonographic contrast medium in monitoring abscess drainage. Seven abscesses were localized and drained with sonographic guidance. Four were in the brain and three were small abscesses in the liver, the subhepatic region, and the pancreas. After aspiration of the purulent material, irrigation with saline produced a highly echogenic sonographic pattern that was free of artifacts and distinctly different from the abscess contents and capsule, and the surrounding parenchyma. In one case, previously unsuspected loculation was detected, requiring repositioning of the needle for complete drainage. All abscesses were resolved and no untoward effects, such as sepsis, were encountered. In one additional patient, microbubble sonographic evaluation was used to monitor the progress of an abscess in which a percutaneous catheter was placed. Saline microbubbles may be used as a sonographic contrast medium to monitor sonography-assisted abscess drainage.

Further modifications for the Frazier suction device. Technical note.

Two modifications of the Frazier suction device are described: a removable distal retractor that is clipped to a modified suction tip and a coupling device that decreases counter-rotational torque.

Sciatica: an early manifestation of thoracic vertebral osteochondroma.

We describe a 36-year-old woman with a thoracic vertebral osteochondroma who presented with radicular leg pain. This benign tumor is uncommon in the vertebral column, and radicular pain is an unusual manifestation of a thoracic spinal lesion. Myelography and computed tomography aided in diagnosis; surgical resection resulted in an excellent clinical response.

Compression-expansion forceps for intracranial dissection and retraction. Technical note.

A hand-held double-bladed retractor has been designed in the form of a cross-action bayonette. It acts to retract both lips of an incision simultaneously. The device can be adapted for other uses.

Spontaneous hemorrhage in a mixed glioma of the cerebellum: case report.

An 8-year-old boy presented in coma and was found to have a massive posterior fossa hemorrhage on computed tomographic scan. Autopsy disclosed a large cerebellar hematoma within a mixed glioma containing both juvenile pilocytic astrocytoma and oligodendroglioma. It is postulated that the hemorrhage originated from the oligodendroglial component of the tumor.

Unruptured intracranial aneurysm and transient focal cerebral ischemia: a follow-up study.

Transient focal cerebral ischemia may occasionally be due to distal embolization of a clot from an unruptured intracranial aneurysm. Follow-up data in 12 such patients revealed no ischemic strokes, subarachnoid or parenchymal hemorrhages in a mean follow-up period of 6.5 years. The aneurysms ranged in size from 2 to 12 mm in diameter, and only two were larger than 10 mm. Two patients had clip ligation of the aneurysm, five patients were given platelet antiaggregation therapy, one was given oral anticoagulants after aortic valve surgery, and four had no specific therapy. The prognosis for unruptured aneurysms presenting with transient focal ischemia was good, regardless of therapy.

Medullomyoblastoma. A histologic, immunohistochemical, and ultrastructural study.

The light and electron microscopic features of a medullomyoblastoma arising in the cerebellar vermis of a 3-year-old boy are described. Differentiation along both glial and neuronal lines was present in the medulloblastoma component of the tumor. Astrocytic differentiation was confirmed by the observation of compact bundles of 8 to 10 nm glial filaments in cellular processes on ultrastructural examination, and by positive immunostaining for glial fibrillary acidic protein (GFAP). Neuroblastic differentiation was suggested by the demonstration of axon-like processes on silver impregnation, and ultrastructurally by the observation of microtubules, dense-core and clear vesicles, and rare synapse-like structures within cytoplasmic processes. The presence of both primitive and well-differentiated striated muscle fibers in the tumor was confirmed by the demonstration of thick and thin myofilaments and Z bands on electron microscopy, and by positive immunostaining for myoglobin. These findings clearly establish the presence of both neuroectodermal and rhabdomyoblastic components in this neoplasm, and thus set it apart from the pure rhabdomyosarcomas, which may also occur in the cerebellar vermis in children. This case also illustrates the usefulness of electron microscopy and immunohistochemistry in the diagnosis and histogenetic evaluation of primitive or poorly differentiated small cell tumors of the central nervous system.

The subarachnoid spaces in children: normal variations in size.

Intra- and extraventricular subarachnoid spaces in children were studied by high-resolution computed tomography. Scans were reviewed of 34 patients who were selected as highly likely to have normal scans. Sizes of the ventricular system and the seven extraventricular subarachnoid compartments were analyzed and graded on a subjective scale from 0 (not visible) to 4 (markedly enlarged). Data were also analyzed by age group (greater or less than 2 years of age). The subarachnoid spaces were found to be both larger and more variable in size before the age of 2 years and to be quite uniform thereafter. Based on these findings, it is inadvisable to base specific diagnoses during the first 2 years of life solely upon modest enlargement of the subarachnoid spaces.

Acute cerebrospinal fluid hydrothorax: a delayed complication of subdural-pleural shunting.

A 31/2-year-old child with a bilateral chronic subdural hematoma due to battering suffered a recurrence on one side. She was treated successfully with a subdural-pleural shunt. Two months later, she returned with severe respiratory embarrassment due to what we think was a cerebrospinal fluid hydrothorax. The maintenance of her earlier neurological recovery was confirmed, and her hydrothorax was cured by removing the shunt. No hydrocephalus ensued.

Intramedullary spinal cord metastasis.

Intramedullary spinal cord metastases are rarely the presenting manifestation of a previously undiagnosed neoplasms. We report such a case in which a subacutely progressive motor and sensory spinal cord syndrome was the initial problem. The differential diagnosis and the difficulties in distinguishing intramedullary from extramedullary mass lesions are discussed. The special features of tumors of the lung and their predilection for metastasis to the central nervous system are considered.

The shoulder abduction test in the diagnosis of radicular pain in cervical extradural compressive monoradiculopathies.

The authors have observed a series of patients with cervical monoradiculopathies due to extradural compressive disease in whom clinical signs included relief of radicular pain with abduction of the shoulder. Of 22 patients requiring myelography for unremitting radicular pain, 15 experienced relief of pain with shoulder abduction. Thirteen patients showing this sign required surgery and all achieved a good result. Two patients were relieved with additional conservative measures. Pain relief obtained with this maneuver seems to occur by decreasing tension on the nerve root. This shoulder abduction relief sign has not been commonly elicited in the past, and the authors wish to bring attention to its value as an indicator of significant cervical extradural radicular compressive disease.