TechniqueDorsal root ganglionectomy for the diagnosis of sensory neuropathies. Surgical technique and results
Introduction
Sensory neuropathies associated or not with an autonomic and with a small or absent motor component may be predominantly secondary to involvement of dorsal root ganglia. Subacute or chronic “polyganglioneuronopathies” [23] occurring in patients not using medications or not exposed to industrial toxic agents may be associated with carcinomas, [5], [25] with Sjögren syndrome, [1], [8], [9], [10], [12], [13], [14], [16], [17] or with monoclonal gammopathies, [4] or may be idiopathic. Idiopathic NISPs [23] are ganglionopathies of unknown nature, although there are suggestions that they may depend on an underlying autoimmune process. Information about the pathology of NISP is limited because few reports are available about autopsies or biopsies of the dorsal root ganglion. These findings include a mononuclear inflammatory infiltrate consisting of T cells of the cytotoxic/suppressor type, [9] deposits of immunoglobulin, [4] and reduced number of neurons with proliferation of satellite cells. No effective treatment exists for NISP, but a clinical improvement occurred in a patient with the use of prednisone. Clinical improvement has been reported for another patient treated with plasmapheresis. [1] There are also reports of spontaneous improvements that, paradoxically, are related to electrophysiological worsening. This fact may depend on functional improvement by adaptation of the patient to his sensory ataxia. [9] However, no controlled studies are available in which the efficacy of any treatment was confirmed. Because there are no estimates of its incidence or prevalence among nonhospital populations and because idiopathic NISP seems not to be frequent, a controlled study of this type should be multicentric.
In view of the above considerations and of the fact that sensory ataxia as well as pain may be incapacitating in patients with NISP, the neurologist, based on the pertinent medical literature and with the patient agreement, is ethically authorized to make attempts to treat with plasmapheresis, corticosteroids, and nonsteroidal immunosuppressive drugs. The doses used, the duration of the therapeutic attempt, and the combination of different types of immunosuppressive treatments mainly depend on the presence of an inflammatory process. This is determined by the detection of an inflammatory infiltrate and/or deposits of immunoglobulins in the sensory ganglia. This detection is possible only by a ganglionectomy, which, however, is an invasive procedure requiring general anesthesia. The procedure should be carried out only after the patient has been fully informed about all surgical steps and risks and only if he is willing to submit to immunosuppressive treatment. Few reports of sensory ganglion exeresis are available. Smith [22] and Osgood et al [19] have described techniques for sensory ganglion exeresis in the thoracic and lumbosacral region, respectively, for the treatment of chronic pain. Griffin et al [9] reported exeresis of a sensory ganglion in the thoracic region for histopathological examination but did not describe in detail the technique used.
The objective of this study was to describe the surgical technique used for exeresis of a dorsal root ganglion in patients with NISP diagnosed based on clinical and EMG criteria [23].
Section snippets
Materials and methods
This study was approved by the Ethical Committee of the Hospital das Clínicas, Ribeirão Preto Medical School, University of São Paulo.
Results
Table 1 presents a summary of the clinical, EMG, and histopathological findings and the surgical technique used in 15 patients submitted to ganglionectomy. No ganglion was included in the removed segment in 2 of 6 patients submitted to en bloc removal of the dural cuff. In all patients submitted to dural cuff opening, the ganglion could be well identified and removed with the dorsal root or en bloc with the ventral and dorsal roots. No surgical complications or postoperative neurological
Clinicopathological comments
Although it was not the aim of this study to analyze the clinicopathological aspects, they deserve comments. No cellular infiltrates or deposits of immunoglobulins were found in the ganglia of our patients. This may be due to the chronicity of our cases (phase without active inflammation), even considering that the disease seemed to be insidious and slowly progressive. Recently, some studies suggested that these ganglionopathies might be associated with antiglycolipid antibodies. [9], [15], [19]
Conclusions
Ganglionectomy of dorsal root ganglion using microsurgical techniques for diagnosis of the NISPs was effective and safe. Although safe, en bloc resection of the proximal dural cuff was not an effective technique for this purpose.
References (27)
- et al.
Polyneuropathie revelatrice d'un syndrome de Gougerot-Sjögren's primitif. Traitement par echanges plasmatiques
Rev Neurol (Paris)
(1987) The blood supply of the human spinal cord
J Neurol Psychiatr
(1939)Chronic idiopathic ataxic neuropathy
Ann Neurol
(1986)Primary sensory neuropathy with muscular changes associated with carcinoma
J Neurol Neurosurg Psychiatry
(1948)- R. Djindjian, M. Hurth, R. Houdart, Angiographie medullaire. Encycl Med Cir Paris, Système Nerveux, 17032 F-10,...
- et al.
Sensory neuronopathy and Sjögren's syndrome: clinical and immunologic study of two patients
Neurology
(1988) - et al.
Ataxic sensory neuropathy and dorsal root ganglionitis associated with Sjögren's syndrome
Ann Neurol
(1990) - et al.
Peripheral neuropathy associated with Sicca syndrome
J Neurol Neurosurg Psychiatry
(1987)
Donnès nouvelles sur la vascularisation de la moelle dorso-lombaire (Application radiologique et intérèt chirurgical)
Rev Neurol
Sjögren's syndrome presenting as a severe sensory neuropathy including involvement of the trigeminal nerve
Br J Rheumatol
Peripheral neuropathy associated with the Sicca syndrome
J Neurol Neurosurg Psychiatry
Cited by (20)
Inflammatory sensory neuronopathies
2024, Revue NeurologiqueDysimmune sensory neuropathies: Diagnostic and therapeutic issues
2021, Bulletin de l'Academie Nationale de MedecineAutoimmune neuropathies associated to rheumatic diseases
2017, Autoimmunity ReviewsCitation Excerpt :Recently, Antoine and cols have identified the fibroblast growth factor receptor 3 (FGFR3) as a target for IgG antibodies in SN patients, that proved to be highly specific (99.6%) but not very sensitive (19%) for SN diagnosis [12]. Those diagnostic strategies were all proposed because the current gold standard test to diagnose SN is invasive, risky and available in few centers (excisional biopsy and histopathological analysis of DRG) [13]. Once the diagnosis of SN is made, the efforts should be driven towards the identification of a possible underlying condition.
Identifying a therapeutic window in acute and subacute inflammatory sensory neuronopathies
2016, Journal of the Neurological SciencesCitation Excerpt :The course also excludes a genetic disease, which has a very chronic evolution and none of the patients had an infectious disease when he or she developed the neuropathy. As several studies have shown that patients with an apparent idiopathic acute or subacute SNN frequently have inflammatory changes in their DRGs [12–14], it is likely that in these patients occurred an inflammatory disorder restricted to the DRG. Although the patients studied here had the common clinical and electrophysiological pattern of SNN, mild variations occurred among the etiological subgroups.
Anatomy of the Dorsal Root Ganglion
2015, Nerves and Nerve InjuriesSensory neuronopathies: A case series and literature review
2021, Journal of the Peripheral Nervous System