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Peter J Jannetta

Publications and source records attributed to Peter J Jannetta.

9 recordsLinked to original sources
PubMed2006

Primary treatment of a blister-like aneurysm with an encircling clip graft: technical case report.

OBJECTIVE: Blister-like aneurysms at nonbranching sites in the supraclinoid portion of the internal carotid artery are a rare but important cause of subarachnoid hemorrhage. We report a case of subarachnoid hemorrhage caused by a ruptured blister-type aneurysm, review the pertinent literature, and hope to remind readers of the wisdom of the use of an encircling clip as the primary treatment of these challenging lesions. CLINICAL PRESENTATION: A 41-year-old woman presented with sudden onset of headache. An admission computed tomographic (CT) scan revealed thick and diffuse subarachnoid hemorrhage involving primarily the carotid cistern and the proximal left sylvian fissure. A cerebral angiogram was initially interpreted as absent for aneurysm, but a follow-up angiogram performed 1 week later confirmed an enlarging aneurysm. INTERVENTION: A craniotomy with placement of an encircling clip graft around a blister-like aneurysm was performed. CONCLUSION: Although Sundt advocated the encircling clip graft for the blister-type aneurysm almost 40 years ago, use of an encircling clip graft in the treatment of blister-like aneurysms of the supraclinoid portion of the internal carotid artery seems to be reserved as a secondary or "rescue" measure in current practice. Neurosurgeons must familiarize themselves with this distinct entity (the blister-type aneurysm), recognize the possible risks associated with parallel clipping, and consider the use of an encircling clip graft as the primary treatment.

Adult↗
PubMed2006

Central brain herniation secondary to fulminant acute disseminated encephalomyelitis: implications for neurosurgical management. Case report.

Acute disseminated encephalomyelitis (ADEM), also known as postinfectious encephalomyelitis, is an immunologically mediated demyelinating disorder affecting the central nervous system that typically occurs after infection or vaccination. The prognosis of ADEM is generally favorable. In a small subset of patients with ADEM, however, fulminant cerebral edema requiring neurosurgical intervention will develop. Few recommendations are available to help the neurosurgeon in dealing with such cases. In this report, the authors present the case of a patient with ADEM in whom central brain herniation developed secondary to medically intractable cerebral edema. The authors review the salient features of the disease and suggest a role for neurosurgeons in cases of fulminant ADEM.

Adult↗
PubMed2005

Dimensions of the posterior fossa in patients symptomatic for Chiari I malformation but without cerebellar tonsillar descent.

BACKGROUND: Chiari I malformation (CMI) is diagnosed by rigid radiographic criteria along with appropriate clinical symptomatology. The aim of this study was to investigate the dimensions of the posterior cranial fossa in patients without significant tonsillar descent but with symptoms comparable to CMI. METHODS: Twenty-two patients with signs and symptoms comparable to CMI but without accepted radiographic criteria of tonsillar descent > 3-5 mm were referred to our clinic for evaluation. A history and physical examination were performed on all patients. In reviewing their MRI scans, nine morphometric measurements were recorded. The measurements were compared to measurements from a cohort of twenty-five individuals with cranial neuralgias from our practice. RESULTS: For patients with Chiari-like symptomatology, the following statistically significant abnormalities were identified: reduced length of the clivus, reduced length of basisphenoid, reduced length of basiocciput, and increased angle of the tentorium. Multiple morphometric studies have demonstrated similar findings in CMI. CONCLUSION: The current classification of CMI is likely too restrictive. Preliminary morphologic data suggests that a subgroup of patients exists with tonsillar descent less than 3 mm below the foramen magnum but with congenitally hypoplastic posterior fossa causing symptomatology consistent with CMI.

Journal Article↗
PubMed2005

Technique of microvascular decompression. Technical note.

Vascular compression of the trigeminal nerve in the cerebellopontine angle is now generally accepted as the primary source or "trigger" causing trigeminal neuralgia. A clear clinicopathological association exists in the neurovascular relationship. In general, pain in the third division of the trigeminal nerve is caused by rostral compression, pain in the second division is caused by medial or more distant compression, and pain in the first division is caused by caudal compression. This discussion of the surgical technique includes details on patient position, placement of the incision and craniectomy, microsurgical exposure of the supralateral cerebellopontine angle, visualization of the trigeminal nerve and vascular pathological features, microvascular decompression, and wound closure. Nuances of the technique are best learned in the company of a surgeon who has a longer experience with this procedure.

Cerebellopontine Angle↗
PubMed2004

Type 2 diabetes mellitus, etiology and possible treatment: preliminary report.

BACKGROUND: Insulin resistance has been proposed as the initial step in the cascade toward type 2 diabetes mellitus. The mechanisms underlying the development of insulin resistance are not fully understood. We hypothesize that neurovascular interactions, in particular arterial elongation, causes compression of the right lateral medulla, triggering a state of autonomic dysfunction including hyperactivity of pancreatic endocrine function, and predisposes to insulin resistance and the development of type 2 diabetes. METHODS: The clinical and operative findings were reviewed retrospectively in 15 patients with primary diagnoses of various right-sided cranial rhizopathies, but with a common diagnosis of type 2 diabetes mellitus. After microvascular decompression was performed for the primary diagnosis, arterial compression was observed of the lateral medulla and cranial nerve X and treated with microvascular decompression. Known duration of the diabetes ranged from "new" (patient was diagnosed as a result of preoperative blood work) to 16 years (mean 7.3 years). Duration of diabetes diagnosis was unknown in 2 patients. Follow-up was from 3 to 113 months (mean 29.9 months). RESULTS: Ten of the 15 patients (66%) showed improvement in their blood glucose control; 5 of those 10 (50%) did so with no (4 patients) or less (1 patient) diabetes medication. CONCLUSIONS: We have shown that arterial compression of the right lateral medulla is consistently present in patients with diabetes mellitus and that microvascular decompression can be performed safely. Further studies are necessary and are under way.

Adult↗
PubMed2002

Direct mechanical stimulation of brainstem modulates cardiac rhythm and repolarization in humans.

Natural mechanical stimulation of the brainstem area by the blood pressure waves propagating in the adjacent arteries plays an important role in the homeostasis of the brainstem centers of cardiovascular control. However, effects of direct mechanical stimulation of this area on the cardiac elecrophysiology have never been studied in humans. In 12 patients (age: 54 +/- 13 years, 5 females) undergoing microvascular decompression, the left (9 patients) or the right (3 patients) side of the ventro-lateral surface of the medulla oblongata was exposed during the surgery, and a mechanical stimulation (duration: 1 min, frequency: 1-2 Hz) of the roots of the cranial nerves and the surface of the brainstem was performed at 3-7 sites using a 2-mm metallic ball. Spatial changes in cardiac repolarization were examined using the 32-lead/192 site electrocardiographic body surface potential maps. Blood pressure was monitored using intra-arterial line. The intervals between the onset of the Q-wave and the offset of the T-wave (QTe) and between the onset of the Q-wave and the peak of the T-wave (QTp), the activation-recovery intervals (ARi), the peak T-wave amplitude, and the QRS and STT integrals were measured using custom software. During the stimulation between the caudal rootlets of the 10th nerve, the peak T-wave amplitude decreased 22% (range: 6-50%) and RR-intervals decreased from 923 +/- 190 to 794 +/- 111 ms compared to the recordings obtained before the stimulation (P =.025 and.063, respectively), whereas QTe, QTp, Ari, and the QRS- and the STT-integrals did not change. Decreased T-wave amplitudes and unchanged QT-intervals suggest that brainstem stimulation might evoke spatially inhomogenious repolarization changes. Stimulation of a localized region surrounding the caudal rootlets of the 10th nerve elicits pronounced effects on cardiac rhythm and repolarization.

Blood Pressure↗
PubMed2002

Commentary.

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Journal Article↗
PubMed2002

Commentary.

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Journal Article↗